The callers of setbat() are actually passing a pgprot_t for the flags
parameter. This doesn't matter unless STRICT_MM_TYPECHECKS is enabled.
So we can turn that on without breaking the build, change setbat() to
take a pgprot_t and have it convert it to an unsigned long internally.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
kmem_cache_create()->kmem_cache_create_memcg()->kstrdup() allocates new
space and copys name's content, so it is safe to free name memory after
calling kmem_cache_create(). Else kmemleak will report the below
warning:
unreferenced object 0xc0000000f9002160 (size 16):
comm "swapper/0", pid 0, jiffies 4294892296 (age 1386.640s)
hex dump (first 16 bytes):
70 67 74 61 62 6c 65 2d 32 5e 39 00 de ad be ef pgtable-2^9.....
backtrace:
[<c0000000004e03ec>] .kvasprintf+0x5c/0xa0
[<c0000000004e045c>] .kasprintf+0x2c/0x50
[<c00000000002e36c>] .pgtable_cache_add+0xac/0x100
[<c00000000002e3e4>] .pgtable_cache_init+0x24/0x80
[<c000000000c6c67c>] .start_kernel+0x228/0x4c8
[<c000000000000594>] .start_here_common+0x24/0x90
Signed-off-by: Yanjiang Jin <yanjiang.jin@windriver.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Use %pS for actual addresses, otherwise you'll get bad output
on arches like ppc64 where %pF expects a function descriptor. Even on
other architectures, refrain from setting a bad example that people
copy.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Raghu noticed an issue with excessive memory allocation on power with a
simple cgroup test, specifically, in mem_cgroup_css_alloc ->
for_each_node -> alloc_mem_cgroup_per_zone_info(), which ends up blowing
up the kmalloc-2048 slab (to the order of 200MB for 400 cgroup
directories).
The underlying issue is that NODES_SHIFT on power is 8 (256 NUMA nodes
possible), which defines node_possible_map, which in turn defines the
value of nr_node_ids in setup_nr_node_ids and the iteration of
for_each_node.
In practice, we never see a system with 256 NUMA nodes, and in fact, we
do not support node hotplug on power in the first place, so the nodes
that are online when we come up are the nodes that will be present for
the lifetime of this kernel. So let's, at least, drop the NUMA possible
map down to the online map at runtime. This is similar to what x86 does
in its initialization routines.
mem_cgroup_css_alloc should also be fixed to only iterate over
memory-populated nodes and handle hotplug, but that is a separate
change.
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The current VPHN parsing logic has some flaws that this patch aims to fix:
1) when the value 0xffff is read, the value 0xffffffff gets added to the
the output list and its element count isn't incremented. This is wrong.
According to PAPR+ the domain identifiers are packed into a sequence
terminated by the "reserved value of all ones". This means that 0xffff
is a stream terminator.
2) the combination of byteswaps and casts make the code hardly readable.
Let's parse the stream one 16-bit field at a time instead.
3) it is assumed that the hypercall returns 12 32-bit values packed into
6 64-bit registers. According to PAPR+, the domain identifiers may be
streamed as 16-bit values. Let's increase the number of expected numbers
to 24.
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The goal behind this patch is to be able to write userland tests for the
VPHN parsing code.
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The first argument to vphn_unpack_associativity() is a const long *, but the
parsing code expects __be64 values actually. Let's move the endian fixing
down for consistency.
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The number of values returned by the H_HOME_NODE_ASSOCIATIVITY h_call deserves
to be explicitly defined, for a better understanding of the code.
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
These functions are only used from one place each. If the cacheable_*
versions really are more efficient, then those changes should be
migrated into the common code instead.
NOTE: The old routines are just flat buggy on kernels that support
hardware with different cacheline sizes.
Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This series tightens the rules for ACCESS_ONCE to only work
on scalar types. It also contains the necessary fixups as
indicated by build bots of linux-next.
Now everything is in place to prevent new non-scalar users
of ACCESS_ONCE and we can continue to convert code to
READ_ONCE/WRITE_ONCE.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/borntraeger/linux
Pull ACCESS_ONCE() rule tightening from Christian Borntraeger:
"Tighten rules for ACCESS_ONCE
This series tightens the rules for ACCESS_ONCE to only work on scalar
types. It also contains the necessary fixups as indicated by build
bots of linux-next. Now everything is in place to prevent new
non-scalar users of ACCESS_ONCE and we can continue to convert code to
READ_ONCE/WRITE_ONCE"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/borntraeger/linux:
kernel: Fix sparse warning for ACCESS_ONCE
next: sh: Fix compile error
kernel: tighten rules for ACCESS ONCE
mm/gup: Replace ACCESS_ONCE with READ_ONCE
x86/spinlock: Leftover conversion ACCESS_ONCE->READ_ONCE
x86/xen/p2m: Replace ACCESS_ONCE with READ_ONCE
ppc/hugetlbfs: Replace ACCESS_ONCE with READ_ONCE
ppc/kvm: Replace ACCESS_ONCE with READ_ONCE
ppc64 should not be depending on DSISR_PROTFAULT and it's unexpected if
they are triggered. This patch adds warnings just in case they are being
accidentally depended upon.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert existing users of pte_numa and friends to the new helper. Note
that the kernel is broken after this patch is applied until the other page
table modifiers are also altered. This patch layout is to make review
easier.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge second set of updates from Andrew Morton:
"More of MM"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (83 commits)
mm/nommu.c: fix arithmetic overflow in __vm_enough_memory()
mm/mmap.c: fix arithmetic overflow in __vm_enough_memory()
vmstat: Reduce time interval to stat update on idle cpu
mm/page_owner.c: remove unnecessary stack_trace field
Documentation/filesystems/proc.txt: describe /proc/<pid>/map_files
mm: incorporate read-only pages into transparent huge pages
vmstat: do not use deferrable delayed work for vmstat_update
mm: more aggressive page stealing for UNMOVABLE allocations
mm: always steal split buddies in fallback allocations
mm: when stealing freepages, also take pages created by splitting buddy page
mincore: apply page table walker on do_mincore()
mm: /proc/pid/clear_refs: avoid split_huge_page()
mm: pagewalk: fix misbehavior of walk_page_range for vma(VM_PFNMAP)
mempolicy: apply page table walker on queue_pages_range()
arch/powerpc/mm/subpage-prot.c: use walk->vma and walk_page_vma()
memcg: cleanup preparation for page table walk
numa_maps: remove numa_maps->vma
numa_maps: fix typo in gather_hugetbl_stats
pagemap: use walk->vma instead of calling find_vma()
clear_refs: remove clear_refs_private->vma and introduce clear_refs_test_walk()
...
Including:
- Update of all defconfigs
- Addition of a bunch of config options to modernise our defconfigs
- Some PS3 updates from Geoff
- Optimised memcmp for 64 bit from Anton
- Fix for kprobes that allows 'perf probe' to work from Naveen
- Several cxl updates from Ian & Ryan
- Expanded support for the '24x7' PMU from Cody & Sukadev
- Freescale updates from Scott:
"Highlights include 8xx optimizations, some more work on datapath device
tree content, e300 machine check support, t1040 corenet error reporting,
and various cleanups and fixes."
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Merge tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull powerpc updates from Michael Ellerman:
- Update of all defconfigs
- Addition of a bunch of config options to modernise our defconfigs
- Some PS3 updates from Geoff
- Optimised memcmp for 64 bit from Anton
- Fix for kprobes that allows 'perf probe' to work from Naveen
- Several cxl updates from Ian & Ryan
- Expanded support for the '24x7' PMU from Cody & Sukadev
- Freescale updates from Scott:
"Highlights include 8xx optimizations, some more work on datapath
device tree content, e300 machine check support, t1040 corenet
error reporting, and various cleanups and fixes"
* tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (102 commits)
cxl: Add missing return statement after handling AFU errror
cxl: Fail AFU initialisation if an invalid configuration record is found
cxl: Export optional AFU configuration record in sysfs
powerpc/mm: Warn on flushing tlb page in kernel context
powerpc/powernv: Add OPAL soft-poweroff routine
powerpc/perf/hv-24x7: Document sysfs event description entries
powerpc/perf/hv-gpci: add the remaining gpci requests
powerpc/perf/{hv-gpci, hv-common}: generate requests with counters annotated
powerpc/perf/hv-24x7: parse catalog and populate sysfs with events
perf: define EVENT_DEFINE_RANGE_FORMAT_LITE helper
perf: add PMU_EVENT_ATTR_STRING() helper
perf: provide sysfs_show for struct perf_pmu_events_attr
powerpc/kernel: Avoid initializing device-tree pointer twice
powerpc: Remove old compile time disabled syscall tracing code
powerpc/kernel: Make syscall_exit a local label
cxl: Fix device_node reference counting
powerpc/mm: bail out early when flushing TLB page
powerpc: defconfigs: add MTD_SPI_NOR (new dependency for M25P80)
perf/powerpc: reset event hw state when adding it to the PMU
powerpc/qe: Use strlcpy()
...
We don't have to use mm_walk->private to pass vma to the callback function
because of mm_walk->vma. And walk_page_vma() is useful if we walk over a
single vma.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently we have many duplicates in definitions around
follow_huge_addr(), follow_huge_pmd(), and follow_huge_pud(), so this
patch tries to remove the m. The basic idea is to put the default
implementation for these functions in mm/hugetlb.c as weak symbols
(regardless of CONFIG_ARCH_WANT_GENERAL_HUGETL B), and to implement
arch-specific code only when the arch needs it.
For follow_huge_addr(), only powerpc and ia64 have their own
implementation, and in all other architectures this function just returns
ERR_PTR(-EINVAL). So this patch sets returning ERR_PTR(-EINVAL) as
default.
As for follow_huge_(pmd|pud)(), if (pmd|pud)_huge() is implemented to
always return 0 in your architecture (like in ia64 or sparc,) it's never
called (the callsite is optimized away) no matter how implemented it is.
So in such architectures, we don't need arch-specific implementation.
In some architecture (like mips, s390 and tile,) their current
arch-specific follow_huge_(pmd|pud)() are effectively identical with the
common code, so this patch lets these architecture use the common code.
One exception is metag, where pmd_huge() could return non-zero but it
expects follow_huge_pmd() to always return NULL. This means that we need
arch-specific implementation which returns NULL. This behavior looks
strange to me (because non-zero pmd_huge() implies that the architecture
supports PMD-based hugepage, so follow_huge_pmd() can/should return some
relevant value,) but that's beyond this cleanup patch, so let's keep it.
Justification of non-trivial changes:
- in s390, follow_huge_pmd() checks !MACHINE_HAS_HPAGE at first, and this
patch removes the check. This is OK because we can assume MACHINE_HAS_HPAGE
is true when follow_huge_pmd() can be called (note that pmd_huge() has
the same check and always returns 0 for !MACHINE_HAS_HPAGE.)
- in s390 and mips, we use HPAGE_MASK instead of PMD_MASK as done in common
code. This patch forces these archs use PMD_MASK, but it's OK because
they are identical in both archs.
In s390, both of HPAGE_SHIFT and PMD_SHIFT are 20.
In mips, HPAGE_SHIFT is defined as (PAGE_SHIFT + PAGE_SHIFT - 3) and
PMD_SHIFT is define as (PAGE_SHIFT + PAGE_SHIFT + PTE_ORDER - 3), but
PTE_ORDER is always 0, so these are identical.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Function __flush_tlb_page() must only be called for user contexts, so
put in extra hardening to warn on calling it for kernel context.
Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
MMU_NO_CONTEXT is conditionally defined as 0 or (unsigned int)-1. However,
in __flush_tlb_page() a corresponding variable is only tested for open
coded 0, which can cause NULL pointer dereference if `mm' argument was
legitimately passed as such.
Bail out early in case the first argument is NULL, thus eliminate confusion
between different values of MMU_NO_CONTEXT and avoid disabling and then
re-enabling preemption unnecessarily.
Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru>
Signed-off-by: Scott Wood <scottwood@freescale.com>
When pages are not 4K, PGDIR table is allocated with kmalloc(). In order to
optimise TLB handlers, aligned memory is needed. kmalloc() doesn't provide
aligned memory blocks, so lets use a kmem_cache pool instead.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
For nohash powerpc, when we run out of contexts, contexts are freed by stealing
used contexts in-turn. When a victim has been selected, the associated TLB
entries are freed using _tlbil_pid(). Unfortunatly, on the PPC 8xx, _tlbil_pid()
does a tlbia, hence flushes ALL TLB entries and not only the one linked to the
stolen context. Therefore, as implented today, at each task switch requiring a
new context, all entries are flushed.
This patch modifies the implementation so that when running out of contexts, all
contexts get freed at once, hence dividing the number of calls to tlbia by 16.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Some powerpc like the 8xx don't have a RW bit in PTE bits but a RO
(Read Only) bit. This patch implements the handling of a _PAGE_RO flag
to be used in place of _PAGE_RW
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[scottwood@freescale.com: fix whitespace]
Signed-off-by: Scott Wood <scottwood@freescale.com>
They seem to be leftovers from '14cf11a powerpc: Merge enough to start
building in arch/powerpc'
Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.
That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works. However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.
In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV. And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.
However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d45 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space. And user space really
expected SIGSEGV, not SIGBUS.
To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it. They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.
This is the mindless minimal patch to do this. A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.
Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.
Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove slice_set_psize() which is not used.
It was added in 3a8247cc2c "powerpc: Only demote individual slices
rather than whole process" but was never used.
Remove vsx_assist_exception() which is not used.
It was added in ce48b21007 "powerpc: Add VSX context save/restore,
ptrace and signal support" but was never used.
Remove generic_mach_cpu_die() which is not used.
Its last caller was removed in 375f561a41 "powerpc/powernv: Always go
into nap mode when CPU is offline".
Remove mpc7448_hpc2_power_off() and mpc7448_hpc2_halt() which are
unused.
These were introduced in c5d56332fd "[POWERPC] Add general support for
mpc7448hpc2 (Taiga) platform" but were never used.
This was partially found by using a static code analysis program called
cppcheck.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
[mpe: Update changelog with details on when/why they are unused]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
ACCESS_ONCE does not work reliably on non-scalar types. For
example gcc 4.6 and 4.7 might remove the volatile tag for such
accesses during the SRA (scalar replacement of aggregates) step
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)
Change the ppc/hugetlbfs code to replace ACCESS_ONCE with READ_ONCE.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Now, we have prepared to avoid using debug-pagealloc in boottime. So
introduce new kernel-parameter to disable debug-pagealloc in boottime, and
makes related functions to be disabled in this case.
Only non-intuitive part is change of guard page functions. Because guard
page is effective only if debug-pagealloc is enabled, turning off
according to debug-pagealloc is reasonable thing to do.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Jungsoo Son <jungsoo.son@lge.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some nice cleanups like removing bootmem, and removal of __get_cpu_var().
There is one patch to mm/gup.c. This is the generic GUP implementation, but is
only used by us and arm(64). We have an ack from Steve Capper, and although we
didn't get an ack from Andrew he told us to take the patch through the powerpc
tree.
There's one cxl patch. This is in drivers/misc, but Greg said he was happy for
us to manage fixes for it.
There is an infrastructure patch to support an IPMI driver for OPAL. That patch
also appears in Corey Minyard's IPMI tree, you may see a conflict there.
There is also an RTC driver for OPAL. We weren't able to get any response from
the RTC maintainer, Alessandro Zummo, so in the end we just merged the driver.
The usual batch of Freescale updates from Scott.
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Merge tag 'powerpc-3.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull powerpc updates from Michael Ellerman:
"Some nice cleanups like removing bootmem, and removal of
__get_cpu_var().
There is one patch to mm/gup.c. This is the generic GUP
implementation, but is only used by us and arm(64). We have an ack
from Steve Capper, and although we didn't get an ack from Andrew he
told us to take the patch through the powerpc tree.
There's one cxl patch. This is in drivers/misc, but Greg said he was
happy for us to manage fixes for it.
There is an infrastructure patch to support an IPMI driver for OPAL.
There is also an RTC driver for OPAL. We weren't able to get any
response from the RTC maintainer, Alessandro Zummo, so in the end we
just merged the driver.
The usual batch of Freescale updates from Scott"
* tag 'powerpc-3.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (101 commits)
powerpc/powernv: Return to cpu offline loop when finished in KVM guest
powerpc/book3s: Fix partial invalidation of TLBs in MCE code.
powerpc/mm: don't do tlbie for updatepp request with NO HPTE fault
powerpc/xmon: Cleanup the breakpoint flags
powerpc/xmon: Enable HW instruction breakpoint on POWER8
powerpc/mm/thp: Use tlbiel if possible
powerpc/mm/thp: Remove code duplication
powerpc/mm/hugetlb: Sanity check gigantic hugepage count
powerpc/oprofile: Disable pagefaults during user stack read
powerpc/mm: Check for matching hpte without taking hpte lock
powerpc: Drop useless warning in eeh_init()
powerpc/powernv: Cleanup unused MCE definitions/declarations.
powerpc/eeh: Dump PHB diag-data early
powerpc/eeh: Recover EEH error on ownership change for BCM5719
powerpc/eeh: Set EEH_PE_RESET on PE reset
powerpc/eeh: Refactor eeh_reset_pe()
powerpc: Remove more traces of bootmem
powerpc/pseries: Initialise nvram_pstore_info's buf_lock
cxl: Name interrupts in /proc/interrupt
cxl: Return error to PSL if IRQ demultiplexing fails & print clearer warning
...
Lots of activity in the devicetree code for v3.18. Most of it is related
to getting all of the overlay support code in place, but there are other
important things in there.
There are a few trivial merge conflicts. They shouldn't give you any
trouble.
Highlights:
- OF_RECONFIG notifiers for SPI, I2C and Platform devices. Those
subsystems can now respond to live changes to the device tree.
- CONFIG_OF_OVERLAY method for applying live changes to the device tree
- Removal of the of_allnodes list. This used to be used to iterate over
all the nodes in the device tree, but it is unnecessary because the
same thing can be done by iterating over the list of child pointers.
Getting rid of of_allnodes saves some memory and avoids the
possibility of of_allnodes being sorted differently from the child
lists.
- Support for retrieving original DTB blob via sysfs. Needed by kexec.
- More unittests
- Documentation and minor bug fixes
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Merge tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux
Pull devicetree changes from Grant Likely:
"Lots of activity in the devicetree code for v3.18. Most of it is
related to getting all of the overlay support code in place, but there
are other important things in there.
Highlights:
- OF_RECONFIG notifiers for SPI, I2C and Platform devices. Those
subsystems can now respond to live changes to the device tree.
- CONFIG_OF_OVERLAY method for applying live changes to the device
tree
- Removal of the of_allnodes list. This used to be used to iterate
over all the nodes in the device tree, but it is unnecessary
because the same thing can be done by iterating over the list of
child pointers. Getting rid of of_allnodes saves some memory and
avoids the possibility of of_allnodes being sorted differently from
the child lists.
- Support for retrieving original DTB blob via sysfs. Needed by
kexec.
- More unittests
- Documentation and minor bug fixes"
* tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux: (42 commits)
of: Delete unnecessary check before calling "of_node_put()"
of: Drop ->next pointer from struct device_node
spi: Check for spi_of_notifier when CONFIG_OF_DYNAMIC=y
of: support passing console options with stdout-path
of: add optional options parameter to of_find_node_by_path()
of: Add bindings for chosen node, stdout-path
of: Remove unneeded and incorrect MODULE_DEVICE_TABLE
ARM: dt: fix up PL011 device tree bindings
of: base, fix of_property_read_string_helper kernel-doc
of: remove select of non-existant OF_DEVICE config symbol
spi/of: Add OF notifier handler
spi/of: Create new device registration method and accessors
i2c/of: Add OF_RECONFIG notifier handler
i2c/of: Factor out Devicetree registration code
of/overlay: Add overlay unittests
of/overlay: Introduce DT overlay support
of/reconfig: Add OF_DYNAMIC notifier for platform_bus_type
of/reconfig: Always use the same structure for notifiers
of/reconfig: Add debug output for OF_RECONFIG notifiers
of/reconfig: Add empty stubs for the of_reconfig methods
...
Changes include:
- Support for alternative instruction patching from Andre
- seccomp from Akashi
- Some AArch32 instruction emulation, required by the Android folks
- Optimisations for exception entry/exit code, cmpxchg, pcpu atomics
- mmu_gather range calculations moved into core code
- EFI updates from Ard, including long-awaited SMBIOS support
- /proc/cpuinfo fixes to align with the format used by arch/arm/
- A few non-critical fixes across the architecture
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"Here's the usual mixed bag of arm64 updates, also including some
related EFI changes (Acked by Matt) and the MMU gather range cleanup
(Acked by you).
Changes include:
- support for alternative instruction patching from Andre
- seccomp from Akashi
- some AArch32 instruction emulation, required by the Android folks
- optimisations for exception entry/exit code, cmpxchg, pcpu atomics
- mmu_gather range calculations moved into core code
- EFI updates from Ard, including long-awaited SMBIOS support
- /proc/cpuinfo fixes to align with the format used by arch/arm/
- a few non-critical fixes across the architecture"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (70 commits)
arm64: remove the unnecessary arm64_swiotlb_init()
arm64: add module support for alternatives fixups
arm64: perf: Prevent wraparound during overflow
arm64/include/asm: Fixed a warning about 'struct pt_regs'
arm64: Provide a namespace to NCAPS
arm64: bpf: lift restriction on last instruction
arm64: Implement support for read-mostly sections
arm64: compat: align cacheflush syscall with arch/arm
arm64: add seccomp support
arm64: add SIGSYS siginfo for compat task
arm64: add seccomp syscall for compat task
asm-generic: add generic seccomp.h for secure computing mode 1
arm64: ptrace: allow tracer to skip a system call
arm64: ptrace: add NT_ARM_SYSTEM_CALL regset
arm64: Move some head.text functions to executable section
arm64: jump labels: NOP out NOP -> NOP replacement
arm64: add support to dump the kernel page tables
arm64: Add FIX_HOLE to permanent fixed addresses
arm64: alternatives: fix pr_fmt string for consistency
arm64: vmlinux.lds.S: don't discard .exit.* sections at link-time
...
upatepp can get called for a nohpte fault when we find from the linux
page table that the translation was hashed before. In that case
we are sure that there is no existing translation, hence we could
avoid doing tlbie.
We could possibly race with a parallel fault filling the TLB. But
that should be ok because updatepp is only ever relaxing permissions.
We also look at linux pte permission bits when filling hash pte
permission bits. We also hold the linux pte busy bits while
inserting/updating a hashpte entry, hence a paralle update of
linux pte is not possible. On the other hand mprotect involves
ptep_modify_prot_start which cause a hpte invalidate and not updatepp.
Performance number:
We use randbox_access_bench written by Anton.
Kernel with THP disabled and smaller hash page table size.
86.60% random_access_b [kernel.kallsyms] [k] .native_hpte_updatepp
2.10% random_access_b random_access_bench [.] doit
1.99% random_access_b [kernel.kallsyms] [k] .do_raw_spin_lock
1.85% random_access_b [kernel.kallsyms] [k] .native_hpte_insert
1.26% random_access_b [kernel.kallsyms] [k] .native_flush_hash_range
1.18% random_access_b [kernel.kallsyms] [k] .__delay
0.69% random_access_b [kernel.kallsyms] [k] .native_hpte_remove
0.37% random_access_b [kernel.kallsyms] [k] .clear_user_page
0.34% random_access_b [kernel.kallsyms] [k] .__hash_page_64K
0.32% random_access_b [kernel.kallsyms] [k] fast_exception_return
0.30% random_access_b [kernel.kallsyms] [k] .hash_page_mm
With Fix:
27.54% random_access_b random_access_bench [.] doit
22.90% random_access_b [kernel.kallsyms] [k] .native_hpte_insert
5.76% random_access_b [kernel.kallsyms] [k] .native_hpte_remove
5.20% random_access_b [kernel.kallsyms] [k] fast_exception_return
5.12% random_access_b [kernel.kallsyms] [k] .__hash_page_64K
4.80% random_access_b [kernel.kallsyms] [k] .hash_page_mm
3.31% random_access_b [kernel.kallsyms] [k] data_access_common
1.84% random_access_b [kernel.kallsyms] [k] .trace_hardirqs_on_caller
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
If we know that user address space has never executed on other cpus
we could use tlbiel.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Rename invalidate_old_hpte to flush_hash_hugepage and use that in
other places.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Limit the number of gigantic hugepages specified by the
hugepages= parameter to MAX_NUMBER_GPAGES.
Signed-off-by: James Yang <James.Yang@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
With smaller hash page table config, we would end up in situation
where we would be replacing hash page table slot frequently. In
such config, we will find the hpte to be not matching, and we
can do that check without holding the hpte lock. We need to
recheck the hpte again after holding lock.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The OF_RECONFIG notifier callback uses a different structure depending
on whether it is a node change or a property change. This is silly, and
not very safe. Rework the code to use the same data structure regardless
of the type of notifier.
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: <linuxppc-dev@lists.ozlabs.org>
Although we are now selecting NO_BOOTMEM, we still have some traces of
bootmem lying around. That is because even with NO_BOOTMEM there is
still a shim that converts bootmem calls into memblock calls, but
ultimately we want to remove all traces of bootmem.
Most of the patch is conversions from alloc_bootmem() to
memblock_virt_alloc(). In general a call such as:
p = (struct foo *)alloc_bootmem(x);
Becomes:
p = memblock_virt_alloc(x, 0);
We don't need the cast because memblock_virt_alloc() returns a void *.
The alignment value of zero tells memblock to use the default alignment,
which is SMP_CACHE_BYTES, the same value alloc_bootmem() uses.
We remove a number of NULL checks on the result of
memblock_virt_alloc(). That is because memblock_virt_alloc() will panic
if it can't allocate, in exactly the same way as alloc_bootmem(), so the
NULL checks are and always have been redundant.
The memory returned by memblock_virt_alloc() is already zeroed, so we
remove several memsets of the result of memblock_virt_alloc().
Finally we convert a few uses of __alloc_bootmem(x, y, MAX_DMA_ADDRESS)
to just plain memblock_virt_alloc(). We don't use memblock_alloc_base()
because MAX_DMA_ADDRESS is ~0ul on powerpc, so limiting the allocation
to that is pointless, 16XB ought to be enough for anyone.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Scott says:
"Highlights include a bunch of 8xx optimizations, device tree bindings
for Freescale BMan, QMan, and FMan datapath components, misc device tree
updates, and inbound rio window support."
On architectures with hardware broadcasting of TLB invalidation messages
, it makes sense to reduce the range of the mmu_gather structure when
unmapping page ranges based on the dirty address information passed to
tlb_remove_tlb_entry.
arm64 already does this by directly manipulating the start/end fields
of the gather structure, but this confuses the generic code which
does not expect these fields to change and can end up calculating
invalid, negative ranges when forcing a flush in zap_pte_range.
This patch moves the minimal range calculation out of the arm64 code
and into the generic implementation, simplifying zap_pte_range in the
process (which no longer needs to care about start/end, since they will
point to the appropriate ranges already). With the range being tracked
by core code, the need_flush flag is dropped in favour of checking that
the end of the range has actually been set.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Michal Simek <monstr@monstr.eu>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch switch the ppc arch to use the generic RCU based
gup implementation.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
PAGE_FACTOR was defined to reflect the difference between configured
page size and fixed 4KB page size. Replace (PAGE_SHIFT - HW_PAGE_SHIFT)
with PAGE_FACTOR.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We did part of sparse initialisation in setup_arch and part in
initmem_init. Put them together.
Signed-off-by: Anton Blanchard <anton@samba.org>
Tested-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Lots of places included bootmem.h even when not using bootmem.
Signed-off-by: Anton Blanchard <anton@samba.org>
Tested-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Now bootmem is gone from powerpc we can remove comments mentioning it.
Signed-off-by: Anton Blanchard <anton@samba.org>
Tested-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
At the moment we transition from the memblock alloctor to the bootmem
allocator. Gitting rid of the bootmem allocator removes a bunch of
complicated code (most of which I owe the dubious honour of being
responsible for writing).
Signed-off-by: Anton Blanchard <anton@samba.org>
Tested-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
8xx sometimes need to load a invalid/non-present TLBs in
it DTLB asm handler.
These must be invalidated separaly as linux mm doesn't.
Commit 5efab4a02c was invalidating them in
arch/powerpc/mm/fault.c.
This patch does the invalidation earlier in order to free the TLB as soon as
possible. This also has the advantage of removing some 8xx specific code from
fault.c
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
We have an extra level of indirection on memory hot remove which is not
matched on memory hot add. Memory hotplug is book3s only, so there is
no need for it.
This also enables means remove_memory() (ie memory hot unplug) works
on powernv.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This still has not been merged and now powerpc is the only arch that does
not have this change. Sorry about missing linuxppc-dev before.
V2->V2
- Fix up to work against 3.18-rc1
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x). This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.
Other use cases are for storing and retrieving data from the current
processors percpu area. __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.
__get_cpu_var() is defined as :
__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.
this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.
This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset. Thereby address calculations are avoided and less registers
are used when code is generated.
At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.
The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e. using a global
register that may be set to the per cpu base.
Transformations done to __get_cpu_var()
1. Determine the address of the percpu instance of the current processor.
DEFINE_PER_CPU(int, y);
int *x = &__get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(&y);
2. Same as #1 but this time an array structure is involved.
DEFINE_PER_CPU(int, y[20]);
int *x = __get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(y);
3. Retrieve the content of the current processors instance of a per cpu
variable.
DEFINE_PER_CPU(int, y);
int x = __get_cpu_var(y)
Converts to
int x = __this_cpu_read(y);
4. Retrieve the content of a percpu struct
DEFINE_PER_CPU(struct mystruct, y);
struct mystruct x = __get_cpu_var(y);
Converts to
memcpy(&x, this_cpu_ptr(&y), sizeof(x));
5. Assignment to a per cpu variable
DEFINE_PER_CPU(int, y)
__get_cpu_var(y) = x;
Converts to
__this_cpu_write(y, x);
6. Increment/Decrement etc of a per cpu variable
DEFINE_PER_CPU(int, y);
__get_cpu_var(y)++
Converts to
__this_cpu_inc(y)
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
[mpe: Fix build errors caused by set/or_softirq_pending(), and rework
assignment in __set_breakpoint() to use memcpy().]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add __init to MMU_setup() which uses __initdata boot_command_line.
Also MMU_setup() is only called from MMU_init(), which is also __init.
Warning appeared since commit 3e47d1474c.
Fixes: 3e47d1474c ("powerpc: Remove powerpc specific cmd_line")
Signed-off-by: Fabian Frederick <fabf@skynet.be>
[mpe: Update changelog]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We received a report of warning in kernel/sched/core.c where the sched
group was NULL on an LPAR after a topology update. This seems to occur
because after the topology update has moved the CPUs, cpu_to_node is
returning the old value still, which ends up breaking the consistency of
the NUMA topology in the per-cpu maps. Ensure that we update the per-cpu
fields when we re-map CPUs.
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There isn't any need to keep referring to update->cpu, as we've already
checked cpu == update->cpu at this point.
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch makes copro_calculate_slb() mask the ESID by the correct mask
for 1T vs 256M segments.
This has no effect by itself as the extra bits were ignored, but it
makes debugging the segment table entries easier and means that we can
directly compare the ESID values for duplicates without needing to worry
about masking in the comparison.
This will be used to simplify a comparison in the following patch.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/mm/slice.c:704:5: error: expected identifier or ‘(’ before numeric constant
int is_hugepage_only_range(struct mm_struct *mm, unsigned long addr,
^
make[1]: *** [arch/powerpc/mm/slice.o] Error 1
make: *** [arch/powerpc/mm/slice.o] Error 2
This got introduced via 1217d34b53
"powerpc: Ensure global functions include their prototype". We
started including linux/hugetlb.h with that patch and now we have
#define is_hugepage_only_range(mm, addr, len) 0
with hugetlbfs disabled.
Fixes: 1217d34b53 ("powerpc: Ensure global functions include their prototype")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull more powerpc updates from Michael Ellerman:
"Here's some more updates for powerpc for 3.18.
They are a bit late I know, though must are actually bug fixes. In my
defence I nearly cut the top of my finger off last weekend in a
gruesome bike maintenance accident, so I spent a good part of the week
waiting around for doctors. True story, I can send photos if you like :)
Probably the most interesting fix is the sys_call_table one, which
enables syscall tracing for powerpc. There's a fix for HMI handling
for old firmware, more endian fixes for firmware interfaces, more EEH
fixes, Anton fixed our routine that gets the current stack pointer,
and a few other misc bits"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (22 commits)
powerpc: Only do dynamic DMA zone limits on platforms that need it
powerpc: sync pseries_le_defconfig with pseries_defconfig
powerpc: Add printk levels to setup_system output
powerpc/vphn: NUMA node code expects big-endian
powerpc/msi: Use WARN_ON() in msi bitmap selftests
powerpc/msi: Fix the msi bitmap alignment tests
powerpc/eeh: Block CFG upon frozen Shiner adapter
powerpc/eeh: Don't collect logs on PE with blocked config space
powerpc/eeh: Block PCI config access upon frozen PE
powerpc/pseries: Drop config requests in EEH accessors
powerpc/powernv: Drop config requests in EEH accessors
powerpc/eeh: Rename flag EEH_PE_RESET to EEH_PE_CFG_BLOCKED
powerpc/eeh: Fix condition for isolated state
powerpc/pseries: Make CPU hotplug path endian safe
powerpc/pseries: Use dump_stack instead of show_stack
powerpc: Rename __get_SP() to current_stack_pointer()
powerpc: Reimplement __get_SP() as a function not a define
powerpc/numa: Add ability to disable and debug topology updates
powerpc/numa: check error return from proc_create
powerpc/powernv: Fallback to old HMI handling behavior for old firmware
...
The associativity domain numbers are obtained from the hypervisor through
registers and written into memory by the guest: the packed array passed to
vphn_unpack_associativity() is then native-endian, unlike what was assumed
in the following commit:
commit b08a2a12e4
Author: Alistair Popple <alistair@popple.id.au>
Date: Wed Aug 7 02:01:44 2013 +1000
powerpc: Make NUMA device node code endian safe
This issue fills the topology with bogus data and makes it unusable. It may
lead to severe performance breakdowns.
We should ideally patch the vphn_unpack_associativity() function to do the
64-bit loads, but this requires some more brain storming.
In the meantime, let's go for a suboptimal and temporary bug fix: this patch
converts each 64-bit value of the packed array to big endian, as expected by
the current parsing code in vphn_unpack_associativity().
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull scheduler updates from Ingo Molnar:
"The main changes in this cycle were:
- Optimized support for Intel "Cluster-on-Die" (CoD) topologies (Dave
Hansen)
- Various sched/idle refinements for better idle handling (Nicolas
Pitre, Daniel Lezcano, Chuansheng Liu, Vincent Guittot)
- sched/numa updates and optimizations (Rik van Riel)
- sysbench speedup (Vincent Guittot)
- capacity calculation cleanups/refactoring (Vincent Guittot)
- Various cleanups to thread group iteration (Oleg Nesterov)
- Double-rq-lock removal optimization and various refactorings
(Kirill Tkhai)
- various sched/deadline fixes
... and lots of other changes"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
sched/dl: Use dl_bw_of() under rcu_read_lock_sched()
sched/fair: Delete resched_cpu() from idle_balance()
sched, time: Fix build error with 64 bit cputime_t on 32 bit systems
sched: Improve sysbench performance by fixing spurious active migration
sched/x86: Fix up typo in topology detection
x86, sched: Add new topology for multi-NUMA-node CPUs
sched/rt: Use resched_curr() in task_tick_rt()
sched: Use rq->rd in sched_setaffinity() under RCU read lock
sched: cleanup: Rename 'out_unlock' to 'out_free_new_mask'
sched: Use dl_bw_of() under RCU read lock
sched/fair: Remove duplicate code from can_migrate_task()
sched, mips, ia64: Remove __ARCH_WANT_UNLOCKED_CTXSW
sched: print_rq(): Don't use tasklist_lock
sched: normalize_rt_tasks(): Don't use _irqsave for tasklist_lock, use task_rq_lock()
sched: Fix the task-group check in tg_has_rt_tasks()
sched/fair: Leverage the idle state info when choosing the "idlest" cpu
sched: Let the scheduler see CPU idle states
sched/deadline: Fix inter- exclusive cpusets migrations
sched/deadline: Clear dl_entity params when setscheduling to different class
sched/numa: Kill the wrong/dead TASK_DEAD check in task_numa_fault()
...
We have hit a few customer issues with the topology update code (VPHN
and PRRN). It would be nice to be able to debug the notifications coming
from the hypervisor in both cases to the LPAR, as well as to disable
responding to the notifications at boot-time, to narrow down the source
of the problems. Add a basic level of such functionality, similar to the
numa= command-line parameter. We already have a toggle in
/proc/powerpc/topology_updates that allows run-time enabling/disabling,
so the updates can be started at run-time if desired. But the bugs we've
run into have occured during boot or very shortly after coming to login,
and have resulted in a broken NUMA topology.
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
proc_create can fail, we should check the return value and pass up the
failure.
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds hooks into the core powerpc mm code for cxl.
The core powerpc code sometimes uses local tlbie. Unfortunately this won't
work with the current cxl driver as it relies on snooping tlbie broadcasts.
The cxl hardware can have TLB entries invalidated via MMIO but this is not
currently supported by the driver. In future we can make local tlbie smarter so
that it invalidates cxl contexts via MMIO when it needs to but for now we have
this workaround.
This workaround checks for any active cxl contexts and if so, disables local
tlbie.
This also adds a hook for when SLBs are invalidated. This ensures any
corresponding SLBs in cxl are also invalidated at the same time. This is
required for segment demotion.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds a new function hash_page_mm() based on the existing hash_page().
This version allows any struct mm to be passed in, rather than assuming
current. This is useful for servicing co-processor faults which are not in the
context of the current running process.
We need to be careful here as the current hash_page() assumes current in a few
places.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Export mmu_kernel_ssize and mmu_linear_psize. These are needed by the cxl
driver which has it's own MMU. To setup the MMU cxl needs access to these.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This moves spu_flush_all_slbs() into a generic call copro_flush_all_slbs().
This will be useful when we add cxl which also needs a similar SLB flush call.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
__spu_trap_data_seg() currently contains code to determine the VSID and ESID
required for a particular EA and mm struct.
This code is generically useful for other co-processors. This moves the code of
the cell platform so it can be used by other powerpc code. It also adds 1TB
segment handling which Cell didn't support. The new function is called
copro_calculate_slb().
This also moves the internal struct spu_slb to a generic struct copro_slb which
is now used in the Cell and copro code. We use this new struct instead of
passing around esid and vsid parameters.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently spu_handle_mm_fault() is in the cell platform.
This code is generically useful for other non-cell co-processors on powerpc.
This patch moves this function out of the cell platform into arch/powerpc/mm so
that others may use it.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Freescale updates from Scott (27 commits):
"Highlights include DMA32 zone support (SATA, USB, etc now works on 64-bit
FSL kernels), MSI changes, 8xx optimizations and cleanup, t104x board
support, and PrPMC PCI enumeration."
There is no need for yet another copy of the command line, just
use boot_command_line like everyone else.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Fill in the si_addr_lsb siginfo field so the hwpoison code can
pass to userspace the length of memory that has been corrupted.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
do_page_fault was missing knowledge of HWPOISON, and we would oops
if userspace tried to access a poisoned page:
kernel BUG at arch/powerpc/mm/fault.c:180!
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Exit out early for a kernel fault, avoiding indenting of
most of the function.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We can unindent the bulk of htab_dt_scan_page_sizes() by returning early
if the property is not found. That is nice in and of itself, but also
has the advantage of making it clear that we always return success once
we have found the ibm,segment-page-sizes property.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
this patches changes some error handling logics in numa_setup_cpu(),
when cpu node is not found, so:
if the cpu is possible, but not present, -1 is kept in numa_cpu_lookup_table,
so later, if the cpu is added, we could set correct numa information for it.
if the cpu is present, then we set the first online node to
numa_cpu_lookup_table instead of 0 ( in case 0 might not be an online node? )
Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
As Nish suggested, it makes more sense to init the numa node informatiion
for present cpus at boottime, which could also avoid WARN_ON(1) in
numa_setup_cpu().
With this change, we also need to change the smp_prepare_cpus() to set up
numa information only on present cpus.
For those possible, but not present cpus, their numa information
will be set up after they are started, as the original code did before commit
2fabf084b6.
Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Tested-by: Cyril Bur <cyril.bur@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
With commit 2fabf084b6 ("powerpc: reorder per-cpu NUMA information's
initialization"), during boottime, cpu_numa_callback() is called
earlier(before their online) for each cpu, and verify_cpu_node_mapping()
uses cpu_to_node() to check whether siblings are in the same node.
It skips the checking for siblings that are not online yet. So the only
check done here is for the bootcpu, which is online at that time. But
the per-cpu numa_node cpu_to_node() uses hasn't been set up yet (which
will be set up in smp_prepare_cpus()).
So I saw something like following reported:
[ 0.000000] CPU thread siblings 1/2/3 and 0 don't belong to the same
node!
As we don't actually do the checking during this early stage, so maybe
we could directly call numa_setup_cpu() in do_init_bootmem().
Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
A recent patch added a function prototype for htab_remove_mapping in
c code. Fix it.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Fix a number of places where global functions were not including
their prototype. This ensures the prototype and the function match.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Commit 1c98025c6c "powerpc: Dynamic DMA
zone limits" updated how zones are created in paging_init(), but missed
the NUMA version of paging_init(). This was noticed via a linker
error, since dma_pfn_limit_to_zone() was, like the non-NUMA
paging_init(), limited by #ifndef CONFIG_NEED_MULTIPLE_NODES.
It turns out that the NUMA paging_init() was not actually doing
anything different from the standard paging_init(), other than a couple
debug prints, a couple 32-bit-only ifdef sections, and a call to
mark_nonram_nosave(). It's not clear whether mark_nonram_nosave() is
inherently wrong to do for NUMA, or just not useful on targets that
have NUMA, but for now I'm preserving the existing behavior.
Fixes: 1c98025c6c "powerpc: Dynamic DMA zone limits"
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Tasks get their end of stack set to STACK_END_MAGIC with the
aim to catch stack overruns. Currently this feature does not
apply to init_task. This patch removes this restriction.
Note that a similar patch was posted by Prarit Bhargava
some time ago but was never merged:
http://marc.info/?l=linux-kernel&m=127144305403241&w=2
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: aneesh.kumar@linux.vnet.ibm.com
Cc: dzickus@redhat.com
Cc: bmr@redhat.com
Cc: jcastillo@redhat.com
Cc: jgh@redhat.com
Cc: minchan@kernel.org
Cc: tglx@linutronix.de
Cc: hannes@cmpxchg.org
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Daeseok Youn <daeseok.youn@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1410527779-8133-2-git-send-email-atomlin@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Platform code can call limit_zone_pfn() to set appropriate limits
for ZONE_DMA and ZONE_DMA32, and dma_direct_alloc_coherent() will
select a suitable zone based on a device's mask and the pfn limits that
platform code has configured.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Shaohui Xie <Shaohui.Xie@freescale.com>
Add tracepoint to track hugepage invalidate. This help us
in debugging difficult to track bugs.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We would get wrong results in compiler recomputed old_pmd. Avoid
that by using ACCESS_ONCE
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
As per ISA, for 4k base page size we compare 14..65 bits of VA specified
with the entry_VA in tlb. That implies we need to make sure we do a
tlbie with all the possible 4k va we used to access the 16MB hugepage.
With 64k base page size we compare 14..57 bits of VA. Hence we cannot
ignore the lower 24 bits of va while tlbie .We also cannot tlb
invalidate a 16MB entry with just one tlbie instruction because
we don't track which va was used to instantiate the tlb entry.
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If we changed base page size of the segment, either via sub_page_protect
or via remap_4k_pfn, we do a demote_segment which doesn't flush the hash
table entries. We do a lazy hash page table flush for all mapped pages
in the demoted segment. This happens when we handle hash page fault for
these pages.
We use _PAGE_COMBO bit along with _PAGE_HASHPTE to indicate whether a
pte is backed by 4K hash pte. If we find _PAGE_COMBO not set on the pte,
that implies that we could possibly have older 64K hash pte entries in
the hash page table and we need to invalidate those entries.
Use _PAGE_COMBO to determine the page size with which we should
invalidate the hash table entries on unmap.
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If we changed base page size of the segment, either via sub_page_protect
or via remap_4k_pfn, we do a demote_segment which doesn't flush the hash
table entries. We do a lazy hash page table flush for all mapped pages
in the demoted segment. This happens when we handle hash page fault
for these pages.
We use _PAGE_COMBO bit along with _PAGE_HASHPTE to indicate whether a
pte is backed by 4K hash pte. If we find _PAGE_COMBO not set on the pte,
that implies that we could possibly have older 64K hash pte entries in
the hash page table and we need to invalidate those entries.
Handle this correctly for 16M pages
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The segment identifier and segment size will remain the same in
the loop, So we can compute it outside. We also change the
hugepage_invalidate interface so that we can use it the later patch
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
With hugepages, we store the hpte valid information in the pte page
whose address is stored in the second half of the PMD. Use a
write barrier to make sure clearing pmd busy bit and updating
hpte valid info are ordered properly.
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There is an issue currently where NUMA information is used on powerpc
(and possibly ia64) before it has been read from the device-tree, which
leads to large slab consumption with CONFIG_SLUB and memoryless nodes.
NUMA powerpc non-boot CPU's cpu_to_node/cpu_to_mem is only accurate
after start_secondary(), similar to ia64, which is invoked via
smp_init().
Commit 6ee0578b4d ("workqueue: mark init_workqueues() as
early_initcall()") made init_workqueues() be invoked via
do_pre_smp_initcalls(), which is obviously before the secondary
processors are online.
Additionally, the following commits changed init_workqueues() to use
cpu_to_node to determine the node to use for kthread_create_on_node:
bce903809a ("workqueue: add wq_numa_tbl_len and
wq_numa_possible_cpumask[]")
f3f90ad469 ("workqueue: determine NUMA node of workers accourding to
the allowed cpumask")
Therefore, when init_workqueues() runs, it sees all CPUs as being on
Node 0. On LPARs or KVM guests where Node 0 is memoryless, this leads to
a high number of slab deactivations
(http://www.spinics.net/lists/linux-mm/msg67489.html).
Fix this by initializing the powerpc-specific CPU<->node/local memory
node mapping as early as possible, which on powerpc is
do_init_bootmem(). Currently that function initializes the mapping for
the boot CPU, but we extend it to setup the mapping for all possible
CPUs. Then, in smp_prepare_cpus(), we can correspondingly set the
per-cpu values for all possible CPUs. That ensures that before the
early_initcalls run (and really as early as possible), the per-cpu NUMA
mapping is accurate.
While testing memoryless nodes on PowerKVM guests with a fix to the
workqueue logic to use cpu_to_mem() instead of cpu_to_node(), with a
guest topology of:
available: 2 nodes (0-1)
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
node 0 size: 0 MB
node 0 free: 0 MB
node 1 cpus: 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99
node 1 size: 16336 MB
node 1 free: 15329 MB
node distances:
node 0 1
0: 10 40
1: 40 10
the slab consumption decreases from
Slab: 932416 kB
SUnreclaim: 902336 kB
to
Slab: 395264 kB
SUnreclaim: 359424 kB
And we a corresponding increase in the slab efficiency from
slab mem objs slabs
used active active
------------------------------------------------------------
kmalloc-16384 337 MB 11.28% 100.00%
task_struct 288 MB 9.93% 100.00%
to
slab mem objs slabs
used active active
------------------------------------------------------------
kmalloc-16384 37 MB 100.00% 100.00%
task_struct 31 MB 100.00% 100.00%
Powerpc didn't support memoryless nodes until recently (64bb80d87f
"powerpc/numa: Enable CONFIG_HAVE_MEMORYLESS_NODES" and 8c27226119
"powerpc/numa: Enable USE_PERCPU_NUMA_NODE_ID"). Those commits also
helped improve memory consumption with these kind of environments.
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
__early_init_mmu() does some things that are really only needed by the
boot cpu. On FSL booke, This includes calling
memblock_enforce_memory_limit(), which is labelled __init. Secondary
cpu init code can't be __init as that would break CPU hotplug.
While it's probably a bug that memblock_enforce_memory_limit() isn't
__init_memblock instead, there's no reason why we should be doing this
stuff for secondary cpus in the first place.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Rather than have architectures #define ARCH_HAS_SG_CHAIN in an
architecture specific scatterlist.h, make it a proper Kconfig option and
use that instead. At same time, remove the header files are are now
mostly useless and just include asm-generic/scatterlist.h.
[sfr@canb.auug.org.au: powerpc files now need asm/dma.h]
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de> [x86]
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [powerpc]
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull powerpc updates from Ben Herrenschmidt:
"This is the powerpc new goodies for 3.17. The short story:
The biggest bit is Michael removing all of pre-POWER4 processor
support from the 64-bit kernel. POWER3 and rs64. This gets rid of a
ton of old cruft that has been bitrotting in a long while. It was
broken for quite a few versions already and nobody noticed. Nobody
uses those machines anymore. While at it, he cleaned up a bunch of
old dusty cabinets, getting rid of a skeletton or two.
Then, we have some base VFIO support for KVM, which allows assigning
of PCI devices to KVM guests, support for large 64-bit BARs on
"powernv" platforms, support for HMI (Hardware Management Interrupts)
on those same platforms, some sparse-vmemmap improvements (for memory
hotplug),
There is the usual batch of Freescale embedded updates (summary in the
merge commit) and fixes here or there, I think that's it for the
highlights"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (102 commits)
powerpc/eeh: Export eeh_iommu_group_to_pe()
powerpc/eeh: Add missing #ifdef CONFIG_IOMMU_API
powerpc: Reduce scariness of interrupt frames in stack traces
powerpc: start loop at section start of start in vmemmap_populated()
powerpc: implement vmemmap_free()
powerpc: implement vmemmap_remove_mapping() for BOOK3S
powerpc: implement vmemmap_list_free()
powerpc: Fail remap_4k_pfn() if PFN doesn't fit inside PTE
powerpc/book3s: Fix endianess issue for HMI handling on napping cpus.
powerpc/book3s: handle HMIs for cpus in nap mode.
powerpc/powernv: Invoke opal call to handle hmi.
powerpc/book3s: Add basic infrastructure to handle HMI in Linux.
powerpc/iommu: Fix comments with it_page_shift
powerpc/powernv: Handle compound PE in config accessors
powerpc/powernv: Handle compound PE for EEH
powerpc/powernv: Handle compound PE
powerpc/powernv: Split ioda_eeh_get_state()
powerpc/powernv: Allow to freeze PE
powerpc/powernv: Enable M64 aperatus for PHB3
powerpc/eeh: Aux PE data for error log
...
This patch introduces zone_for_memory() to arch_add_memory() on powerpc
to ensure new, higher memory added into ZONE_MOVABLE if movable zone has
already setup.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Mel Gorman" <mgorman@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
vmemmap_populated() checks whether the [start, start + page_size) has valid
pfn numbers, to know whether a vmemmap mapping has been created that includes
this range.
Some range before end might not be checked by this loop:
sec11start......start11..sec11end/sec12start..end....start12..sec12end
as the above, for start11(section 11), it checks [sec11start, sec11end), and
loop ends as the next start(start12) is bigger than end. However,
[sec11end/sec12start, end) is not checked here.
So before the loop, adjust the start to be the start of the section, so we don't miss ranges like the above.
After we adjust start to be the start of the section, it also means it's
aligned with vmemmap as of the sizeof struct page, so we could use
page_to_pfn directly in the loop.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
vmemmap_free() does the opposite of vmemap_populate().
This patch also puts vmemmap_free() and vmemmap_list_free() into
CONFIG_MEMMORY_HOTPLUG.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is to be called in vmemmap_free(), leave the implementation on BOOK3E
empty as before.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch implements vmemmap_list_free() for vmemmap_free().
The freed entries will be removed from vmemmap_list, and form a freed list,
with next as the header. The next position in the last allocated page is kept
at the list tail.
When allocation, if there are freed entries left, get it from the freed list;
if no freed entries left, get it like before from the last allocated pages.
With this change, realmode_pfn_to_page() also needs to be changed to walk
all the entries in the vmemmap_list, as the virt_addr of the entries might not
be stored in order anymore.
It helps to reuse the memory when continuous doing memory hot-plug/remove
operations, but didn't reclaim the pages already allocated, so the memory usage
will only increase, but won't exceed the value for the largest memory
configuration.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This silences a section mismatch warning. early_alloc_pgtable() is
called from map_kernel_page() which cannot be __init, but only when
slab_is_available() returns false which can only happen during early
boot.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Scott writes:
Highlights include e6500 hardware threading support, an e6500 TLB erratum
workaround, corenet error reporting, support for a new board, and some
minor fixes.
Erratum A-008139 can cause duplicate TLB entries if an indirect
entry is overwritten using tlbwe while the other thread is using it to
do a lookup. Work around this by using tlbilx to invalidate prior
to overwriting.
To avoid the need to save another register to hold MAS1 during the
workaround code, TID clearing has been moved from tlb_miss_kernel_e6500
until after the SMT section.
Signed-off-by: Scott Wood <scottwood@freescale.com>
There are still a few occurences where it remains, because it helps to
explain something that persists.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now that we have dropped power3 support we can remove CONFIG_POWER3. The
usage in pgtable_32.c was already dead code as CONFIG_POWER3 was not
selectable on PPC32.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We now only support cpus that use an SLB, so we don't need an MMU
feature to indicate that.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Old cpus didn't have a Segment Lookaside Buffer (SLB), instead they had
a Segment Table (STAB). Now that we've dropped support for those cpus,
we can remove the STAB support entirely.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In fb5a515704 "powerpc: Remove platforms/wsp and associated pieces",
we removed the last user of MMU_FTRS_A2. So remove it.
MMU_FTRS_A2 was the last user of MMU_FTR_TYPE_3E, so remove it also.
This leaves some unreachable code in mmu_context_nohash.c, so remove
that also.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Virtualized environments may expose a e6500 dual-threaded core
as two single-threaded e6500 cores. Take advantage of this
and get rid of the tlb lock and the trap-causing tlbsx in
the htw miss handler by guarding with CPU_FTR_SMT, as it's
already being done in the bolted tlb1 miss handler.
As seen in the results below, measurements done with lmbench
random memory access latency test running under Freescale's
Embedded Hypervisor, there is a ~34% improvement.
Memory latencies in nanoseconds - smaller is better
(WARNING - may not be correct, check graphs)
----------------------------------------------------
Host Mhz L1 $ L2 $ Main mem Rand mem
--------- --- ---- ---- -------- --------
smt 1665 1.8020 13.2 83.0 1149.7
nosmt 1665 1.8020 13.2 83.0 758.1
Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
Cc: Scott Wood <scottwood@freescale.com>
[scottwood@freescale.com: commit message tweak]
Signed-off-by: Scott Wood <scottwood@freescale.com>
Commit 82d86de25b "TLB lock recursive"
introduced a bug whereby cpu 0 uses the same value for "lock held" as
is used to indicate that the lock is free. This means that cpu 1 can
acquire the lock whenever it wants, regardless of whether cpu 0 has it
locked, which in turn means we can get duplicate TLB entries.
Add one to the CPU value to ensure we do not use zero as a "lock held"
value.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Reported-by: Ed Swarthout <ed.swarthout@freescale.com>
Previously TID was being cleared before the tlbsx, but not after. This
can lead to a multiway hit between a TLB entry with TID=0 (previously
inserted when PID=0) and a TLB entry with TID!=0 that matches PID.
This can theoretically result in undefined behavior, though we probably
get lucky due to the details of the overlap. It also results in the
inability to use multihit detection to detect other conflicting TLB
entries, as well as poorer TLB utilization due to duplicating kernel
TLB entries.
Rather than try to patch up MAS1 after tlbsx, the entire value is
saved/restored as with MAS2.
I observed a slight improvement in TLB miss performance with this patch
applied.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Reported-by: Ed Swarthout <ed.swarthout@freescale.com>
Pull powerpc updates from Ben Herrenschmidt:
"Here is the bulk of the powerpc changes for this merge window. It got
a bit delayed in part because I wasn't paying attention, and in part
because I discovered I had a core PCI change without a PCI maintainer
ack in it. Bjorn eventually agreed it was ok to merge it though we'll
probably improve it later and I didn't want to rebase to add his ack.
There is going to be a bit more next week, essentially fixes that I
still want to sort through and test.
The biggest item this time is the support to build the ppc64 LE kernel
with our new v2 ABI. We previously supported v2 userspace but the
kernel itself was a tougher nut to crack. This is now sorted mostly
thanks to Anton and Rusty.
We also have a fairly big series from Cedric that add support for
64-bit LE zImage boot wrapper. This was made harder by the fact that
traditionally our zImage wrapper was always 32-bit, but our new LE
toolchains don't really support 32-bit anymore (it's somewhat there
but not really "supported") so we didn't want to rely on it. This
meant more churn that just endian fixes.
This brings some more LE bits as well, such as the ability to run in
LE mode without a hypervisor (ie. under OPAL firmware) by doing the
right OPAL call to reinitialize the CPU to take HV interrupts in the
right mode and the usual pile of endian fixes.
There's another series from Gavin adding EEH improvements (one day we
*will* have a release with less than 20 EEH patches, I promise!).
Another highlight is the support for the "Split core" functionality on
P8 by Michael. This allows a P8 core to be split into "sub cores" of
4 threads which allows the subcores to run different guests under KVM
(the HW still doesn't support a partition per thread).
And then the usual misc bits and fixes ..."
[ Further delayed by gmail deciding that BenH is a dirty spammer.
Google knows. ]
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (155 commits)
powerpc/powernv: Add missing include to LPC code
selftests/powerpc: Test the THP bug we fixed in the previous commit
powerpc/mm: Check paca psize is up to date for huge mappings
powerpc/powernv: Pass buffer size to OPAL validate flash call
powerpc/pseries: hcall functions are exported to modules, need _GLOBAL_TOC()
powerpc: Exported functions __clear_user and copy_page use r2 so need _GLOBAL_TOC()
powerpc/powernv: Set memory_block_size_bytes to 256MB
powerpc: Allow ppc_md platform hook to override memory_block_size_bytes
powerpc/powernv: Fix endian issues in memory error handling code
powerpc/eeh: Skip eeh sysfs when eeh is disabled
powerpc: 64bit sendfile is capped at 2GB
powerpc/powernv: Provide debugfs access to the LPC bus via OPAL
powerpc/serial: Use saner flags when creating legacy ports
powerpc: Add cpu family documentation
powerpc/xmon: Fix up xmon format strings
powerpc/powernv: Add calls to support little endian host
powerpc: Document sysfs DSCR interface
powerpc: Fix regression of per-CPU DSCR setting
powerpc: Split __SYSFS_SPRSETUP macro
arch: powerpc/fadump: Cleaning up inconsistent NULL checks
...
We have a bug in our hugepage handling which exhibits as an infinite
loop of hash faults. If the fault is being taken in the kernel it will
typically trigger the softlockup detector, or the RCU stall detector.
The bug is as follows:
1. mmap(0xa0000000, ..., MAP_FIXED | MAP_HUGE_TLB | MAP_ANONYMOUS ..)
2. Slice code converts the slice psize to 16M.
3. The code on lines 539-540 of slice.c in slice_get_unmapped_area()
synchronises the mm->context with the paca->context. So the paca slice
mask is updated to include the 16M slice.
3. Either:
* mmap() fails because there are no huge pages available.
* mmap() succeeds and the mapping is then munmapped.
In both cases the slice psize remains at 16M in both the paca & mm.
4. mmap(0xa0000000, ..., MAP_FIXED | MAP_ANONYMOUS ..)
5. The slice psize is converted back to 64K. Because of the check on line 539
of slice.c we DO NOT update the paca->context. The paca slice mask is now
out of sync with the mm slice mask.
6. User/kernel accesses 0xa0000000.
7. The SLB miss handler slb_allocate_realmode() **uses the paca slice mask**
to create an SLB entry and inserts it in the SLB.
18. With the 16M SLB entry in place the hardware does a hash lookup, no entry
is found so a data access exception is generated.
19. The data access handler calls do_page_fault() -> handle_mm_fault().
10. __handle_mm_fault() creates a THP mapping with do_huge_pmd_anonymous_page().
11. The hardware retries the access, there is still nothing in the hash table
so once again a data access exception is generated.
12. hash_page() calls into __hash_page_thp() and inserts a mapping in the
hash. Although the THP mapping maps 16M the hashing is done using 64K
as the segment page size.
13. hash_page() returns immediately after calling __hash_page_thp(), skipping
over the code at line 1125. Resulting in the mismatch between the
paca->context and mm->context not being detected.
14. The hardware retries the access, the hash it generates using the 16M
SLB entry does NOT match the hash we inserted.
15. We take another data access and go into __hash_page_thp().
16. We see a valid entry in the hpte_slot_array and so we call updatepp()
which succeeds.
17. Goto 14.
We could fix this in two ways. The first would be to remove or modify
the check on line 539 of slice.c.
The second option is to cause the check of paca psize in hash_page() on
line 1125 to also be done for THP pages.
We prefer the latter, because the check & update of the paca psize is
not done until we know it's necessary. It's also done only on the
current cpu, so we don't need to IPI all other cpus.
Without further rearranging the code, the simplest fix is to pull out
the code that checks paca psize and call it in two places. Firstly for
THP/hugetlb, and secondly for other mappings as before.
Thanks to Dave Jones for trinity, which originally found this bug.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@vger.kernel.org [v3.11+]
Currently hugepage migration is available for all archs which support
pmd-level hugepage, but testing is done only for x86_64 and there're
bugs for other archs. So to avoid breaking such archs, this patch
limits the availability strictly to x86_64 until developers of other
archs get interested in enabling this feature.
Simply disabling hugepage migration on non-x86_64 archs is not enough to
fix the reported problem where sys_move_pages() hits the BUG_ON() in
follow_page(FOLL_GET), so let's fix this by checking if hugepage
migration is supported in vma_migratable().
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: <stable@vger.kernel.org> [3.12+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Another round of clean-up of FDT related code in architecture code.
This removes knowledge of internal FDT details from most architectures
except powerpc.
- Conversion of kernel's custom FDT parsing code to use libfdt.
- DT based initialization for generic serial earlycon. The introduction
of generic serial earlycon support went in thru tty tree.
- Improve the platform device naming for DT probed devices to ensure
unique naming and use parent names instead of a global index.
- Fix a race condition in of_update_property.
- Unify the various linker section OF match tables and fix several
function prototype errors.
- Update platform_get_irq_byname to work in deferred probe cases.
- 2 binding doc updates
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Merge tag 'devicetree-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux into next
Pull DeviceTree updates from Rob Herring:
- Another round of clean-up of FDT related code in architecture code.
This removes knowledge of internal FDT details from most
architectures except powerpc.
- Conversion of kernel's custom FDT parsing code to use libfdt.
- DT based initialization for generic serial earlycon. The
introduction of generic serial earlycon support went in through the
tty tree.
- Improve the platform device naming for DT probed devices to ensure
unique naming and use parent names instead of a global index.
- Fix a race condition in of_update_property.
- Unify the various linker section OF match tables and fix several
function prototype errors.
- Update platform_get_irq_byname to work in deferred probe cases.
- 2 binding doc updates
* tag 'devicetree-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (58 commits)
of: handle NULL node in next_child iterators
of/irq: provide more wrappers for !CONFIG_OF
devicetree: bindings: Document micrel vendor prefix
dt: bindings: dwc2: fix required value for the phy-names property
of_pci_irq: kill useless variable in of_irq_parse_pci()
of/irq: do irq resolution in platform_get_irq_byname()
of: Add a testcase for of_find_node_by_path()
of: Make of_find_node_by_path() handle /aliases
of: Create unlocked version of for_each_child_of_node()
lib: add glibc style strchrnul() variant
of: Handle memory@0 node on PPC32 only
pci/of: Remove dead code
of: fix race between search and remove in of_update_property()
of: Use NULL for pointers
of: Stop naming platform_device using dcr address
of: Ensure unique names without sacrificing determinism
tty/serial: pl011: add DT based earlycon support
of/fdt: add FDT serial scanning for earlycon
of/fdt: add FDT address translation support
serial: earlycon: add DT support
...
was a pretty active cycle for KVM. Changes include:
- a lot of s390 changes: optimizations, support for migration,
GDB support and more
- ARM changes are pretty small: support for the PSCI 0.2 hypercall
interface on both the guest and the host (the latter acked by Catalin)
- initial POWER8 and little-endian host support
- support for running u-boot on embedded POWER targets
- pretty large changes to MIPS too, completing the userspace interface
and improving the handling of virtualized timer hardware
- for x86, a larger set of changes is scheduled for 3.17. Still,
we have a few emulator bugfixes and support for running nested
fully-virtualized Xen guests (para-virtualized Xen guests have
always worked). And some optimizations too.
The only missing architecture here is ia64. It's not a coincidence
that support for KVM on ia64 is scheduled for removal in 3.17.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm into next
Pull KVM updates from Paolo Bonzini:
"At over 200 commits, covering almost all supported architectures, this
was a pretty active cycle for KVM. Changes include:
- a lot of s390 changes: optimizations, support for migration, GDB
support and more
- ARM changes are pretty small: support for the PSCI 0.2 hypercall
interface on both the guest and the host (the latter acked by
Catalin)
- initial POWER8 and little-endian host support
- support for running u-boot on embedded POWER targets
- pretty large changes to MIPS too, completing the userspace
interface and improving the handling of virtualized timer hardware
- for x86, a larger set of changes is scheduled for 3.17. Still, we
have a few emulator bugfixes and support for running nested
fully-virtualized Xen guests (para-virtualized Xen guests have
always worked). And some optimizations too.
The only missing architecture here is ia64. It's not a coincidence
that support for KVM on ia64 is scheduled for removal in 3.17"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (203 commits)
KVM: add missing cleanup_srcu_struct
KVM: PPC: Book3S PR: Rework SLB switching code
KVM: PPC: Book3S PR: Use SLB entry 0
KVM: PPC: Book3S HV: Fix machine check delivery to guest
KVM: PPC: Book3S HV: Work around POWER8 performance monitor bugs
KVM: PPC: Book3S HV: Make sure we don't miss dirty pages
KVM: PPC: Book3S HV: Fix dirty map for hugepages
KVM: PPC: Book3S HV: Put huge-page HPTEs in rmap chain for base address
KVM: PPC: Book3S HV: Fix check for running inside guest in global_invalidates()
KVM: PPC: Book3S: Move KVM_REG_PPC_WORT to an unused register number
KVM: PPC: Book3S: Add ONE_REG register names that were missed
KVM: PPC: Add CAP to indicate hcall fixes
KVM: PPC: MPIC: Reset IRQ source private members
KVM: PPC: Graciously fail broken LE hypercalls
PPC: ePAPR: Fix hypercall on LE guest
KVM: PPC: BOOK3S: Remove open coded make_dsisr in alignment handler
KVM: PPC: BOOK3S: Always use the saved DAR value
PPC: KVM: Make NX bit available with magic page
KVM: PPC: Disable NX for old magic page using guests
KVM: PPC: BOOK3S: HV: Add mixed page-size support for guest
...
On LPAR guest systems Linux enables the shadow SLB to indicate to the
hypervisor a number of SLB entries that always have to be available.
Today we go through this shadow SLB and disable all ESID's valid bits.
However, pHyp doesn't like this approach very much and honors us with
fancy machine checks.
Fortunately the shadow SLB descriptor also has an entry that indicates
the number of valid entries following. During the lifetime of a guest
we can just swap that value to 0 and don't have to worry about the
SLB restoration magic.
While we're touching the code, let's also make it more readable (get
rid of rldicl), allow it to deal with a dynamic number of bolted
SLB entries and only do shadow SLB swizzling on LPAR systems.
Signed-off-by: Alexander Graf <agraf@suse.de>
The only way Freescale booke chips support mappings larger than 4K
is via TLB1. The only way we support (direct) TLB1 entries is via
hugetlb, which is not what map_kernel_page() does when given a large
page size.
Without this, a kernel with CONFIG_SPARSEMEM_VMEMMAP enabled crashes on
boot with messages such as:
PID hash table entries: 4096 (order: 3, 32768 bytes)
Sorting __ex_table...
BUG: Bad page state in process swapper pfn:00a2f
page:8000040000023a48 count:0 mapcount:0 mapping:0000040000ffce48 index:0x40000ffbe50
page flags: 0x40000ffda40(active|arch_1|private|private_2|head|tail|swapcache|mappedtodisk|reclaim|swapbacked|unevictable|mlocked)
page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
bad because of flags:
page flags: 0x311840(active|private|private_2|swapcache|unevictable|mlocked)
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 3.15.0-rc1-00003-g7fa250c #299
Call Trace:
[c00000000098ba20] [c000000000008b3c] .show_stack+0x7c/0x1cc (unreliable)
[c00000000098baf0] [c00000000060aa50] .dump_stack+0x88/0xb4
[c00000000098bb70] [c0000000000c0468] .bad_page+0x144/0x1a0
[c00000000098bc10] [c0000000000c0628] .free_pages_prepare+0x164/0x17c
[c00000000098bcc0] [c0000000000c24cc] .free_hot_cold_page+0x48/0x214
[c00000000098bd60] [c00000000086c318] .free_all_bootmem+0x1fc/0x354
[c00000000098be70] [c00000000085da84] .mem_init+0xac/0xdc
[c00000000098bef0] [c0000000008547b0] .start_kernel+0x21c/0x4d4
[c00000000098bf90] [c000000000000448] .start_here_common+0x20/0x58
Signed-off-by: Scott Wood <scottwood@freescale.com>
This request includes a few bug fixes that really shouldn't wait for the next
release.
It fixes KVM on 32bit PowerPC when built as module. It also fixes the PV KVM
acceleration when NX gets honored by the host. Furthermore we fix transactional
memory support and numa support on HV KVM.
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Merge tag 'signed-for-3.15' of git://github.com/agraf/linux-2.6 into kvm-master
Patch queue for 3.15 - 2014-05-12
This request includes a few bug fixes that really shouldn't wait for the next
release.
It fixes KVM on 32bit PowerPC when built as module. It also fixes the PV KVM
acceleration when NX gets honored by the host. Furthermore we fix transactional
memory support and numa support on HV KVM.
This series adds support for building the powerpc 64-bit
LE kernel using the new ABI v2. We already supported
running ABI v2 userspace programs but this adds support
for building the kernel itself using the new ABI.
In case of extending the eaddr in future, use this macro
PGTABLE_EADDR_SIZE to ease the maintenance of the code.
Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When we never get around to seeing an HEA ethernet adapter, there's
no point in restricting ourselves to 4k IO page size.
This speeds up IO maps when CONFIG_IBMEBUS is disabled.
[ Updated the test to also lift the restriction on arch 2.07
(Power 8) which cannot have an HEA
-- BenH ]
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
foo
Make of_get_flat_dt_prop arguments compatible with libfdt fdt_getprop
call in preparation to convert FDT code to use libfdt. Make the return
value const and the property length ptr type an int.
Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Stephen Chivers <schivers@csc.com>
Our PV guest patching code assembles chunks of instructions on the fly when it
encounters more complicated instructions to hijack. These instructions need
to live in a section that we don't mark as non-executable, as otherwise we
fault when jumping there.
Right now we put it into the .bss section where it automatically gets marked
as non-executable. Add a check to the NX setting function to ensure that we
leave these particular pages executable.
Signed-off-by: Alexander Graf <agraf@suse.de>
The if condition check was based on a draft ISA doc. Remove the same.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The MMU hashtable and SLB branch patching code uses function
pointers for the update sites. This creates a difference between
ABIv1 and ABIv2 because we don't have function descriptors on
ABIv2.
Get rid of the function pointer and just point at the update
sites directly. This works on both ABIs.
Signed-off-by: Anton Blanchard <anton@samba.org>
binutils is smart enough to know that a branch to a function
descriptor is actually a branch to the functions text address.
Alan tells me that binutils has been doing this for 9 years.
Signed-off-by: Anton Blanchard <anton@samba.org>
Since v1:
Edited the comment according to Srivatsa's suggestion.
During the testing, we encounter below WARN followed by Oops:
WARNING: at kernel/sched/core.c:6218
...
NIP [c000000000101660] .build_sched_domains+0x11d0/0x1200
LR [c000000000101358] .build_sched_domains+0xec8/0x1200
PACATMSCRATCH [800000000000f032]
Call Trace:
[c00000001b103850] [c000000000101358] .build_sched_domains+0xec8/0x1200
[c00000001b1039a0] [c00000000010aad4] .partition_sched_domains+0x484/0x510
[c00000001b103aa0] [c00000000016d0a8] .rebuild_sched_domains+0x68/0xa0
[c00000001b103b30] [c00000000005cbf0] .topology_work_fn+0x10/0x30
...
Oops: Kernel access of bad area, sig: 11 [#1]
...
NIP [c00000000045c000] .__bitmap_weight+0x60/0xf0
LR [c00000000010132c] .build_sched_domains+0xe9c/0x1200
PACATMSCRATCH [8000000000029032]
Call Trace:
[c00000001b1037a0] [c000000000288ff4] .kmem_cache_alloc_node_trace+0x184/0x3a0
[c00000001b103850] [c00000000010132c] .build_sched_domains+0xe9c/0x1200
[c00000001b1039a0] [c00000000010aad4] .partition_sched_domains+0x484/0x510
[c00000001b103aa0] [c00000000016d0a8] .rebuild_sched_domains+0x68/0xa0
[c00000001b103b30] [c00000000005cbf0] .topology_work_fn+0x10/0x30
...
This was caused by that 'sd->groups == NULL' after building groups, which
was caused by the empty 'sd->span'.
The cpu's domain contained nothing because the cpu was assigned to a wrong
node, due to the following unfortunate sequence of events:
1. The hypervisor sent a topology update to the guest OS, to notify changes
to the cpu-node mapping. However, the update was actually redundant - i.e.,
the "new" mapping was exactly the same as the old one.
2. Due to this, the 'updated_cpus' mask turned out to be empty after exiting
the 'for-loop' in arch_update_cpu_topology().
3. So we ended up calling stop-machine() with an empty cpumask list, which made
stop-machine internally elect cpumask_first(cpu_online_mask), i.e., CPU0 as
the cpu to run the payload (the update_cpu_topology() function).
4. This causes update_cpu_topology() to be run by CPU0. And since 'updates'
is kzalloc()'ed inside arch_update_cpu_topology(), update_cpu_topology()
finds update->cpu as well as update->new_nid to be 0. In other words, we
end up assigning CPU0 (and eventually its siblings) to node 0, incorrectly.
Along with the following wrong updating, it causes the sched-domain rebuild
code to break and crash the system.
Fix this by skipping the topology update in cases where we find that
the topology has not actually changed in reality (ie., spurious updates).
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Nathan Fontenot <nfont@linux.vnet.ibm.com>
CC: Stephen Rothwell <sfr@canb.auug.org.au>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Robert Jennings <rcj@linux.vnet.ibm.com>
CC: Jesse Larrew <jlarrew@linux.vnet.ibm.com>
CC: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
CC: Alistair Popple <alistair@popple.id.au>
Suggested-by: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We need to handle numa pte via the slow path
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Freescale updates from Scott. Mostly support for critical
and machine check exceptions on 64-bit BookE, some new
PCI suspend/resume work and misc bits.
We have generic code like the one in get_futex_key that assume that
a local_irq_disable prevents a parallel THP split. Support that by
adding a dummy smp call function after setting _PAGE_SPLITTING. Code
paths like get_user_pages_fast still need to check for _PAGE_SPLITTING
after disabling IRQ which indicate that a parallel THP splitting is
ongoing. Now if they don't find _PAGE_SPLITTING set, then we can be
sure that parallel split will now block in pmdp_splitting flush
until we enables IRQ
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add special state saving for critical and machine check exceptions.
Most of this code could be used to handle debug exceptions taken from
kernel space, but actually doing so is outside the scope of this patch.
The various critical and machine check exceptions now point to their
real handlers, rather than hanging the kernel.
Signed-off-by: Scott Wood <scottwood@freescale.com>
While bolted handlers (including e6500) do not need to deal with a TLB
miss recursively causing another TLB miss, nested TLB misses can still
happen with crit/mc/debug exceptions -- so we still need to honor
SPRG_TLB_EXFRAME.
We don't need to spend time modifying it in the TLB miss fastpath,
though -- the special level exception will handle that.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Mihai Caraman <mihai.caraman@freescale.com>
Cc: kvm-ppc@vger.kernel.org
Once special level interrupts are supported, we may take nested TLB
misses -- so allow the same thread to acquire the lock recursively.
The lock will not be effective against the nested TLB miss handler
trying to write the same entry as the interrupted TLB miss handler, but
that's also a problem on non-threaded CPUs that lack TLB write
conditional. This will be addressed in the patch that enables crit/mc
support by invalidating the TLB on return from level exceptions.
Signed-off-by: Scott Wood <scottwood@freescale.com>
The previous code added wrong TLBs and causes machine check errors if
a driver accessed passed the end of the linear mapping instead of
a clean page fault.
Signed-off-by: Ralph E. Bellofatto <ralphbel@us.ibm.com>
Signed-off-by: Benjamin Krill <ben@codiert.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The memory remove code for powerpc/pseries should call remove_memory()
so that we are holding the hotplug_memory lock during memory remove
operations.
This patch updates the memory node remove handler to call remove_memory()
and adds a ppc_md.remove_memory() entry to handle pseries specific work
that is called from arch_remove_memory().
During memory remove in pseries_remove_memblock() we have to stay with
removing memory one section at a time. This is needed because of how memory
resources are handled. During memory add for pseries (via the probe file in
sysfs) we add memory one section at a time which gives us a memory resource
for each section. Future patches will aim to address this so will not have
to remove memory one section at a time.
Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pte_update() is a powerpc-ism used to change the bits of a PTE
when the access permission is being restricted (a flush is
potentially needed).
It uses atomic operations on when needed and handles the hash
synchronization on hash based processors.
It is currently only used to clear PTE bits and so the current
implementation doesn't provide a way to also set PTE bits.
The new _PAGE_NUMA bit, when set, is actually restricting access
so it must use that function too, so this change adds the ability
for pte_update() to also set bits.
We will use this later to set the _PAGE_NUMA bit.
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
On p8 systems, with relocation on exception feature enabled we are seeing
kdump kernel hang at interrupt vector 0xc*4400. The reason is, with this
feature enabled, exception are raised with MMU (IR=DR=1) ON with the
default offset of 0xc*4000. Since exception is raised in virtual mode it
requires the vector region to be executable without which it fails to
fetch and execute instruction at 0xc*4xxx. For default kernel since kernel
is loaded at real 0, the htab mappings sets the entire kernel text region
executable. But for relocatable kernel (e.g. kdump case) we only copy
interrupt vectors down to real 0 and never marked that region as
executable because in p7 and below we always get exception in real mode.
This patch fixes this issue by marking htab mapping range as executable
that overlaps with the interrupt vector region for relocatable kernel.
Thanks to Ben who helped me to debug this issue and find the root cause.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
