Commit Graph

65 Commits

Author SHA1 Message Date
Christophe Leroy
1408fca0c1 powerpc/mm: Make slice specific to book3s/64
Since commit 555904d07e ("powerpc/8xx: MM_SLICE is not needed
anymore") only book3s/64 selects CONFIG_PPC_MM_SLICES.

Move slice.c into mm/book3s64/

Move necessary stuff in asm/book3s/64/slice.h and
remove asm/slice.h

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4a0d74ef1966a5902b5fd4ac4b513a760a6d675a.1649523076.git.christophe.leroy@csgroup.eu
2022-05-05 22:11:57 +10:00
Nicholas Piggin
387e220a2e powerpc/64s: Move hash MMU support code under CONFIG_PPC_64S_HASH_MMU
Compiling out hash support code when CONFIG_PPC_64S_HASH_MMU=n saves
128kB kernel image size (90kB text) on powernv_defconfig minus KVM,
350kB on pseries_defconfig minus KVM, 40kB on a tiny config.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fixup defined(ARCH_HAS_MEMREMAP_COMPAT_ALIGN), which needs CONFIG.
      Fix radix_enabled() use in setup_initial_memory_limit(). Add some
      stubs to reduce number of ifdefs.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211201144153.2456614-18-npiggin@gmail.com
2021-12-09 22:41:13 +11:00
Zhang Yunkai
1a0e4550fb powerpc: Remove duplicate includes
asm/tm.h included in traps.c is duplicated. It is also included on
the 62nd line.

asm/udbg.h included in setup-common.c is duplicated. It is also
included on the 61st line.

asm/bug.h included in arch/powerpc/include/asm/book3s/64/mmu-hash.h
is duplicated. It is also included on the 12th line.

asm/tlbflush.h included in arch/powerpc/include/asm/pgtable.h is
duplicated. It is also included on the 11th line.

asm/page.h included in arch/powerpc/include/asm/thread_info.h is
duplicated. It is also included on the 13th line.

Signed-off-by: Zhang Yunkai <zhang.yunkai@zte.com.cn>
[mpe: Squash together from multiple commits]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2021-03-24 14:09:30 +11:00
Nicholas Piggin
3a96570ffc powerpc: convert interrupt handlers to use wrappers
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210130130852.2952424-29-npiggin@gmail.com
2021-02-09 00:02:12 +11:00
Nicholas Piggin
a01a3f2ddb powerpc: remove arguments from fault handler functions
Make mm fault handlers all just take the pt_regs * argument and load
DAR/DSISR from that. Make those that return a value return long.

This is done to make the function signatures match other handlers, which
will help with a future patch to add wrappers. Explicit arguments could
be added for performance but that would require more wrapper macro
variants.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210130130852.2952424-7-npiggin@gmail.com
2021-02-09 00:02:08 +11:00
Nicholas Piggin
a4922f5442 powerpc/64s: move the hash fault handling logic to C
The fault handling still has some complex logic particularly around
hash table handling, in asm. Implement most of this in C.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210130130852.2952424-6-npiggin@gmail.com
2021-02-09 00:02:08 +11:00
Cédric Le Goater
1f55aefea3 powerpc/mm: Declare preload_new_slb_context() prototype
It fixes this W=1 compile error :

../arch/powerpc/mm/book3s64/slb.c:380:6: error: no previous prototype for ‘preload_new_slb_context’ [-Werror=missing-prototypes]
  380 | void preload_new_slb_context(unsigned long start, unsigned long sp)
      |      ^~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210104143206.695198-15-clg@kaod.org
2021-01-30 11:39:30 +11:00
Cédric Le Goater
11f9c1d2fb powerpc/mm: Move hpte_insert_repeating() prototype
It fixes this W=1 compile error :

../arch/powerpc/mm/book3s64/hash_utils.c:1867:6: error: no previous prototype for ‘hpte_insert_repeating’ [-Werror=missing-prototypes]
 1867 | long hpte_insert_repeating(unsigned long hash, unsigned long vpn,
      |      ^~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210104143206.695198-14-clg@kaod.org
2021-01-30 11:39:29 +11:00
Cédric Le Goater
cccaf1a10a powerpc/mm: Declare some prototypes
It fixes this W=1 compile error :

../arch/powerpc/mm/book3s64/hash_utils.c:1515:5: error: no previous prototype for ‘__hash_page’ [-Werror=missing-prototypes]
 1515 | int __hash_page(unsigned long trap, unsigned long ea, unsigned long dsisr,
      |     ^~~~~~~~~~~
../arch/powerpc/mm/book3s64/hash_utils.c:1850:6: error: no previous prototype for ‘low_hash_fault’ [-Werror=missing-prototypes]
 1850 | void low_hash_fault(struct pt_regs *regs, unsigned long address, int rc)
      |      ^~~~~~~~~~~~~~

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210104143206.695198-13-clg@kaod.org
2021-01-30 11:39:29 +11:00
Ganesh Goudar
3ba150fb21 lkdtm/powerpc: Add SLB multihit test
To check machine check handling, add support to inject slb
multihit errors.

Co-developed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
[mpe: Use CONFIG_PPC_BOOK3S_64 to fix compile errors reported by lkp@intel.com]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201130083057.135610-1-ganeshgr@linux.ibm.com
2020-12-04 01:01:34 +11:00
Aneesh Kumar K.V
d94b827e89 powerpc/book3s64/kuap: Use Key 3 for kernel mapping with hash translation
This patch updates kernel hash page table entries to use storage key 3
for its mapping. This implies all kernel access will now use key 3 to
control READ/WRITE. The patch also prevents the allocation of key 3 from
userspace and UAMOR value is updated such that userspace cannot modify key 3.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201127044424.40686-9-aneesh.kumar@linux.ibm.com
2020-12-04 01:01:25 +11:00
Aneesh Kumar K.V
b32d5d7e92 powerpc/mm/book3s: Split radix and hash MAX_PHYSMEM limit
MAX_PHYSMEM #define is used along with sparsemem to determine the SECTION_SHIFT
value. Powerpc also uses the same value to limit the max memory enabled on the
system. With 4K PAGE_SIZE and hash translation mode, we want to limit the max
memory enabled to 64TB due to page table size restrictions. However, with
radix translation, we don't have these restrictions. Hence split the radix
and hash MA_PHYSMEM limit and use different limit for each of them.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200608070904.387440-4-aneesh.kumar@linux.ibm.com
2020-09-15 22:13:22 +10:00
Randy Dunlap
10a4a016d6 powerpc/book3s/mmu-hash.h: delete duplicated word
Drop the repeated word "below".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200726003809.20454-2-rdunlap@infradead.org
2020-07-27 00:01:31 +10:00
Aneesh Kumar K.V
33699023f5 powerpc/book3s64/pkeys: Fixup bit numbering
This number the pkey bit such that it is easy to follow. PKEY_BIT0 is
the lower order bit. This makes further changes easy to follow.

No functional change in this patch other than linux page table for
hash translation now maps pkeys differently.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200709032946.881753-3-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:57 +10:00
Aneesh Kumar K.V
5d2e5dd584 powerpc/mm/hash: Fix sharing context ids between kernel & userspace
Commit 0034d395f8 ("powerpc/mm/hash64: Map all the kernel regions in
the same 0xc range") has a bug in the definition of MIN_USER_CONTEXT.

The result is that the context id used for the vmemmap and the lowest
context id handed out to userspace are the same. The context id is
essentially the process identifier as far as the first stage of the
MMU translation is concerned.

This can result in multiple SLB entries with the same VSID (Virtual
Segment ID), accessible to the kernel and some random userspace
process that happens to get the overlapping id, which is not expected
eg:

  07 c00c000008000000 40066bdea7000500  1T  ESID=   c00c00  VSID=      66bdea7 LLP:100
  12 0002000008000000 40066bdea7000d80  1T  ESID=      200  VSID=      66bdea7 LLP:100

Even though the user process and the kernel use the same VSID, the
permissions in the hash page table prevent the user process from
reading or writing to any kernel mappings.

It can also lead to SLB entries with different base page size
encodings (LLP), eg:

  05 c00c000008000000 00006bde0053b500 256M ESID=c00c00000  VSID=    6bde0053b LLP:100
  09 0000000008000000 00006bde0053bc80 256M ESID=        0  VSID=    6bde0053b LLP:  0

Such SLB entries can result in machine checks, eg. as seen on a G5:

  Oops: Machine check, sig: 7 [#1]
  BE PAGE SIZE=64K MU-Hash SMP NR_CPUS=4 NUMA Power Mac
  NIP: c00000000026f248 LR: c000000000295e58 CTR: 0000000000000000
  REGS: c0000000erfd3d70 TRAP: 0200 Tainted: G M (5.5.0-rcl-gcc-8.2.0-00010-g228b667d8ea1)
  MSR: 9000000000109032 <SF,HV,EE,ME,IR,DR,RI> CR: 24282048 XER: 00000000
  DAR: c00c000000612c80 DSISR: 00000400 IRQMASK: 0
  ...
  NIP [c00000000026f248] .kmem_cache_free+0x58/0x140
  LR  [c088000008295e58] .putname 8x88/0xa
  Call Trace:
    .putname+0xB8/0xa
    .filename_lookup.part.76+0xbe/0x160
    .do_faccessat+0xe0/0x380
    system_call+0x5c/ex68

This happens with 256MB segments and 64K pages, as the duplicate VSID
is hit with the first vmemmap segment and the first user segment, and
older 32-bit userspace maps things in the first user segment.

On other CPUs a machine check is not seen. Instead the userspace
process can get stuck continuously faulting, with the fault never
properly serviced, due to the kernel not understanding that there is
already a HPTE for the address but with inaccessible permissions.

On machines with 1T segments we've not seen the bug hit other than by
deliberately exercising it. That seems to be just a matter of luck
though, due to the typical layout of the user virtual address space
and the ranges of vmemmap that are typically populated.

To fix it we add 2 to MIN_USER_CONTEXT. This ensures the lowest
context given to userspace doesn't overlap with the VMEMMAP context,
or with the context for INVALID_REGION_ID.

Fixes: 0034d395f8 ("powerpc/mm/hash64: Map all the kernel regions in the same 0xc range")
Cc: stable@vger.kernel.org # v5.2+
Reported-by: Christian Marillat <marillat@debian.org>
Reported-by: Romain Dolbeau <romain@dolbeau.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Account for INVALID_REGION_ID, mostly rewrite change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200123102547.11623-1-mpe@ellerman.id.au
2020-01-23 21:26:20 +11:00
Thomas Gleixner
2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Aneesh Kumar K.V
5f53d28608 powerpc/mm/hash: Rename KERNEL_REGION_ID to LINEAR_MAP_REGION_ID
The region actually point to linear map. Rename the #define to
clarify thati.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:40 +10:00
Aneesh Kumar K.V
1c946c1b7f powerpc/mm/hash: Simplify the region id calculation.
This reduces multiple comparisons in get_region_id to a bit shift operation.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:40 +10:00
Aneesh Kumar K.V
0034d395f8 powerpc/mm/hash64: Map all the kernel regions in the same 0xc range
This patch maps vmalloc, IO and vmemap regions in the 0xc address range
instead of the current 0xd and 0xf range. This brings the mapping closer
to radix translation mode.

With hash 64K page size each of this region is 512TB whereas with 4K config
we are limited by the max page table range of 64TB and hence there regions
are of 16TB size.

The kernel mapping is now:

 On 4K hash

     kernel_region_map_size = 16TB
     kernel vmalloc start   = 0xc000100000000000
     kernel IO start        = 0xc000200000000000
     kernel vmemmap start   = 0xc000300000000000

64K hash, 64K radix and 4k radix:

     kernel_region_map_size = 512TB
     kernel vmalloc start   = 0xc008000000000000
     kernel IO start        = 0xc00a000000000000
     kernel vmemmap start   = 0xc00c000000000000

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:39 +10:00
Aneesh Kumar K.V
ef629cc5bf powerc/mm/hash: Reduce hash_mm_context size
Allocate subpage protect related variables only if we use the feature.
This helps in reducing the hash related mm context struct by around 4K

Before the patch
sizeof(struct hash_mm_context)  = 8288

After the patch
sizeof(struct hash_mm_context) = 4160

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:39 +10:00
Aneesh Kumar K.V
701101865f powerpc/mm: Reduce memory usage for mm_context_t for radix
Currently, our mm_context_t on book3s64 include all hash specific
context details like slice mask and subpage protection details. We
can skip allocating these with radix translation. This will help us to save
8K per mm_context with radix translation.

With the patch applied we have

sizeof(mm_context_t)  = 136
sizeof(struct hash_mm_context)  = 8288

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:39 +10:00
Aneesh Kumar K.V
60458fba46 powerpc/mm: Add helpers for accessing hash translation related variables
We want to switch to allocating them runtime only when hash translation is
enabled. Add helpers so that both book3s and nohash can be adapted to
upcoming change easily.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:38 +10:00
Christophe Leroy
92ab45c5f2 powerpc: Avoid circular header inclusion in mmu-hash.h
When activating CONFIG_THREAD_INFO_IN_TASK, linux/sched.h includes
asm/current.h. This generates a circular dependency. To avoid that,
asm/processor.h shall not be included in mmu-hash.h.

In order to do that, this patch moves into a new header called
asm/task_size_64/32.h all the TASK_SIZE related constants, which can
then be included in mmu-hash.h directly.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out all the TASK_SIZE constants not just 64-bit ones]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:39 +11:00
Linus Torvalds
685f7e4f16 Merge tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - A large series to rewrite our SLB miss handling, replacing a lot of
     fairly complicated asm with much fewer lines of C.

   - Following on from that, we now maintain a cache of SLB entries for
     each process and preload them on context switch. Leading to a 27%
     speedup for our context switch benchmark on Power9.

   - Improvements to our handling of SLB multi-hit errors. We now print
     more debug information when they occur, and try to continue running
     by flushing the SLB and reloading, rather than treating them as
     fatal.

   - Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9).

   - Add support for physical memory up to 2PB in the linear mapping on
     64-bit Book3S. We only support up to 512TB as regular system
     memory, otherwise the percpu allocator runs out of vmalloc space.

   - Add stack protector support for 32 and 64-bit, with a per-task
     canary.

   - Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP.

   - Support recognising "big cores" on Power9, where two SMT4 cores are
     presented to us as a single SMT8 core.

   - A large series to cleanup some of our ioremap handling and PTE
     flags.

   - Add a driver for the PAPR SCM (storage class memory) interface,
     allowing guests to operate on SCM devices (acked by Dan).

   - Changes to our ftrace code to handle very large kernels, where we
     need to use a trampoline to get to ftrace_caller().

  And many other smaller enhancements and cleanups.

  Thanks to: Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton
  Blanchard, Aravinda Prasad, Bartlomiej Zolnierkiewicz, Benjamin
  Herrenschmidt, Breno Leitao, Cédric Le Goater, Christophe Leroy,
  Christophe Lombard, Dan Carpenter, Daniel Axtens, Finn Thain, Gautham
  R. Shenoy, Gustavo Romero, Haren Myneni, Hari Bathini, Jia Hongtao,
  Joel Stanley, John Allen, Laurent Dufour, Madhavan Srinivasan, Mahesh
  Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael Bringmann,
  Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan
  Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver
  O'Halloran, Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab,
  Rob Herring, Sam Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan
  Johnson, Stephen Rothwell, Stewart Smith, Suraj Jitindar Singh, Tyrel
  Datwyler, Vaibhav Jain, Vasant Hegde, YueHaibing, zhong jiang"

* tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (221 commits)
  Revert "selftests/powerpc: Fix out-of-tree build errors"
  powerpc/msi: Fix compile error on mpc83xx
  powerpc: Fix stack protector crashes on CPU hotplug
  powerpc/traps: restore recoverability of machine_check interrupts
  powerpc/64/module: REL32 relocation range check
  powerpc/64s/radix: Fix radix__flush_tlb_collapsed_pmd double flushing pmd
  selftests/powerpc: Add a test of wild bctr
  powerpc/mm: Fix page table dump to work on Radix
  powerpc/mm/radix: Display if mappings are exec or not
  powerpc/mm/radix: Simplify split mapping logic
  powerpc/mm/radix: Remove the retry in the split mapping logic
  powerpc/mm/radix: Fix small page at boundary when splitting
  powerpc/mm/radix: Fix overuse of small pages in splitting logic
  powerpc/mm/radix: Fix off-by-one in split mapping logic
  powerpc/ftrace: Handle large kernel configs
  powerpc/mm: Fix WARN_ON with THP NUMA migration
  selftests/powerpc: Fix out-of-tree build errors
  powerpc/time: no steal_time when CONFIG_PPC_SPLPAR is not selected
  powerpc/time: Only set CONFIG_ARCH_HAS_SCALED_CPUTIME on PPC64
  powerpc/time: isolate scaled cputime accounting in dedicated functions.
  ...
2018-10-26 14:36:21 -07:00
Aneesh Kumar K.V
4ffe713b75 powerpc/mm: Increase the max addressable memory to 2PB
Currently we limit the max addressable memory to 128TB. This patch increase the
limit to 2PB. We can have devices like nvdimm which adds memory above 512TB
limit.

We still don't support regular system ram above 512TB. One of the challenge with
that is the percpu allocator, that allocates per node memory and use the max
distance between them as the percpu offsets. This means with large gap in
address space ( system ram above 1PB) we will run out of vmalloc space to map
the percpu allocation.

In order to support addressable memory above 512TB, kernel should be able to
linear map this range. To do that with hash translation we now add 4 context
to kernel linear map region. Our per context addressable range is 512TB. We
still keep VMALLOC and VMEMMAP region to old size. SLB miss handlers is updated
to validate these limit.

We also limit this update to SPARSEMEM_VMEMMAP and SPARSEMEM_EXTREME

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Nicholas Piggin
94ee42727c powerpc/64s/hash: Simplify slb_flush_and_rebolt()
slb_flush_and_rebolt() is misleading, it is called in virtual mode, so
it can not possibly change the stack, so it should not be touching the
shadow area. And since vmalloc is no longer bolted, it should not
change any bolted mappings at all.

Change the name to slb_flush_and_restore_bolted(), and have it just
load the kernel stack from what's currently in the shadow SLB area.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Nicholas Piggin
425d331462 powerpc/64s/hash: Provide arch_setup_exec() hooks for hash slice setup
This will be used by the SLB code in the next patch, but for now this
sets the slb_addr_limit to the correct size for 32-bit tasks.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Suraj Jitindar Singh
e3b6b46615 KVM: PPC: Book3S HV: Implement H_TLB_INVALIDATE hcall
When running a nested (L2) guest the guest (L1) hypervisor will use
the H_TLB_INVALIDATE hcall when it needs to change the partition
scoped page tables or the partition table which it manages.  It will
use this hcall in the situations where it would use a partition-scoped
tlbie instruction if it were running in hypervisor mode.

The H_TLB_INVALIDATE hcall can invalidate different scopes:

Invalidate TLB for a given target address:
- This invalidates a single L2 -> L1 pte
- We need to invalidate any L2 -> L0 shadow_pgtable ptes which map the L2
  address space which is being invalidated. This is because a single
  L2 -> L1 pte may have been mapped with more than one pte in the
  L2 -> L0 page tables.

Invalidate the entire TLB for a given LPID or for all LPIDs:
- Invalidate the entire shadow_pgtable for a given nested guest, or
  for all nested guests.

Invalidate the PWC (page walk cache) for a given LPID or for all LPIDs:
- We don't cache the PWC, so nothing to do.

Invalidate the entire TLB, PWC and partition table for a given/all LPIDs:
- Here we re-read the partition table entry and remove the nested state
  for any nested guest for which the first doubleword of the partition
  table entry is now zero.

The H_TLB_INVALIDATE hcall takes as parameters the tlbie instruction
word (of which only the RIC, PRS and R fields are used), the rS value
(giving the lpid, where required) and the rB value (giving the IS, AP
and EPN values).

[paulus@ozlabs.org - adapted to having the partition table in guest
memory, added the H_TLB_INVALIDATE implementation, removed tlbie
instruction emulation, reworded the commit message.]

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09 16:04:27 +11:00
Michael Ellerman
54be0b9c7c Revert "convert SLB miss handlers to C" and subsequent commits
This reverts commits:
  5e46e29e6a ("powerpc/64s/hash: convert SLB miss handlers to C")
  8fed04d0f6 ("powerpc/64s/hash: remove user SLB data from the paca")
  655deecf67 ("powerpc/64s/hash: SLB allocation status bitmaps")
  2e1626744e ("powerpc/64s/hash: provide arch_setup_exec hooks for hash slice setup")
  89ca4e126a ("powerpc/64s/hash: Add a SLB preload cache")

This series had a few bugs, and the fixes are not all trivial. So
revert most of it for now.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-03 15:32:49 +10:00
Nicholas Piggin
2e1626744e powerpc/64s/hash: provide arch_setup_exec hooks for hash slice setup
This will be used by the SLB code in the next patch, but for now this
sets the slb_addr_limit to the correct size for 32-bit tasks.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 22:01:56 +10:00
Nicholas Piggin
8fed04d0f6 powerpc/64s/hash: remove user SLB data from the paca
User SLB mappig data is copied into the PACA from the mm->context so
it can be accessed by the SLB miss handlers.

After the C conversion, SLB miss handlers now run with relocation on,
and user SLB misses are able to take recursive kernel SLB misses, so
the user SLB mapping data can be removed from the paca and accessed
directly.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 22:01:46 +10:00
Nicholas Piggin
85376e2a17 powerpc/64s/hash: remove the vmalloc segment from the bolted SLB
Remove the vmalloc segment from bolted SLBEs. This is not required to
be bolted, and seems like it was added to help pre-load the SLB on
context switch. However there are now other segments like the vmemmap
segment and non-zero node memory that often take misses after a context
switch, so it is better to solve this in a more general way.

A subsequent change will track free SLB entries and uses those rather
than round-robin overwrite valid entries, which makes it far less
likely for kernel SLBEs to be evicted after they are installed.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 21:59:41 +10:00
Mahesh Salgaonkar
c6d15258cd powerpc/pseries: Dump the SLB contents on SLB MCE errors.
If we get a machine check exceptions due to SLB errors then dump the
current SLB contents which will be very much helpful in debugging the
root cause of SLB errors. Introduce an exclusive buffer per cpu to hold
faulty SLB entries. In real mode mce handler saves the old SLB contents
into this buffer accessible through paca and print it out later in virtual
mode.

With this patch the console will log SLB contents like below on SLB MCE
errors:

[  507.297236] SLB contents of cpu 0x1
[  507.297237] Last SLB entry inserted at slot 16
[  507.297238] 00 c000000008000000 400ea1b217000500
[  507.297239]   1T  ESID=   c00000  VSID=      ea1b217 LLP:100
[  507.297240] 01 d000000008000000 400d43642f000510
[  507.297242]   1T  ESID=   d00000  VSID=      d43642f LLP:110
[  507.297243] 11 f000000008000000 400a86c85f000500
[  507.297244]   1T  ESID=   f00000  VSID=      a86c85f LLP:100
[  507.297245] 12 00007f0008000000 4008119624000d90
[  507.297246]   1T  ESID=       7f  VSID=      8119624 LLP:110
[  507.297247] 13 0000000018000000 00092885f5150d90
[  507.297247]  256M ESID=        1  VSID=   92885f5150 LLP:110
[  507.297248] 14 0000010008000000 4009e7cb50000d90
[  507.297249]   1T  ESID=        1  VSID=      9e7cb50 LLP:110
[  507.297250] 15 d000000008000000 400d43642f000510
[  507.297251]   1T  ESID=   d00000  VSID=      d43642f LLP:110
[  507.297252] 16 d000000008000000 400d43642f000510
[  507.297253]   1T  ESID=   d00000  VSID=      d43642f LLP:110
[  507.297253] ----------------------------------
[  507.297254] SLB cache ptr value = 3
[  507.297254] Valid SLB cache entries:
[  507.297255] 00 EA[0-35]=    7f000
[  507.297256] 01 EA[0-35]=        1
[  507.297257] 02 EA[0-35]=     1000
[  507.297257] Rest of SLB cache entries:
[  507.297258] 03 EA[0-35]=    7f000
[  507.297258] 04 EA[0-35]=        1
[  507.297259] 05 EA[0-35]=     1000
[  507.297260] 06 EA[0-35]=       12
[  507.297260] 07 EA[0-35]=    7f000

Suggested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 21:59:41 +10:00
Nicholas Piggin
e7e8184747 powerpc/64s: move machine check SLB flushing to mm/slb.c
The machine check code that flushes and restores bolted segments in
real mode belongs in mm/slb.c. This will also be used by pseries
machine check and idle code in future changes.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-10 22:12:39 +10:00
Christophe Leroy
ec0c464cdb powerpc: move ASM_CONST and stringify_in_c() into asm-const.h
This patch moves ASM_CONST() and stringify_in_c() into
dedicated asm-const.h, then cleans all related inclusions.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: asm-compat.h should include asm-const.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-30 22:48:16 +10:00
Aneesh Kumar K.V
a833280b4a powerpc/mm/hash: Add hpte_get_old_v and use that instead of opencoding
No functional change

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24 22:03:18 +10:00
Ram Pai
a6590ca55f powerpc: Program HPTE key protection bits
Map the PTE protection key bits to the HPTE key protection bits,
while creating HPTE  entries.

Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:03 +11:00
Nicholas Piggin
4722476bce powerpc/64s: mm_context.addr_limit is only used on hash
Radix keeps no meaningful state in addr_limit, so remove it from radix
code and rename to slb_addr_limit to make it clear it applies to hash
only.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-13 23:35:43 +11:00
Linus Torvalds
0756b7fbb6 Merge tag 'kvm-4.14-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Radim Krčmář:
 "First batch of KVM changes for 4.14

  Common:
   - improve heuristic for boosting preempted spinlocks by ignoring
     VCPUs in user mode

  ARM:
   - fix for decoding external abort types from guests

   - added support for migrating the active priority of interrupts when
     running a GICv2 guest on a GICv3 host

   - minor cleanup

  PPC:
   - expose storage keys to userspace

   - merge kvm-ppc-fixes with a fix that missed 4.13 because of
     vacations

   - fixes

  s390:
   - merge of kvm/master to avoid conflicts with additional sthyi fixes

   - wire up the no-dat enhancements in KVM

   - multiple epoch facility (z14 feature)

   - Configuration z/Architecture Mode

   - more sthyi fixes

   - gdb server range checking fix

   - small code cleanups

  x86:
   - emulate Hyper-V TSC frequency MSRs

   - add nested INVPCID

   - emulate EPTP switching VMFUNC

   - support Virtual GIF

   - support 5 level page tables

   - speedup nested VM exits by packing byte operations

   - speedup MMIO by using hardware provided physical address

   - a lot of fixes and cleanups, especially nested"

* tag 'kvm-4.14-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (67 commits)
  KVM: arm/arm64: Support uaccess of GICC_APRn
  KVM: arm/arm64: Extract GICv3 max APRn index calculation
  KVM: arm/arm64: vITS: Drop its_ite->lpi field
  KVM: arm/arm64: vgic: constify seq_operations and file_operations
  KVM: arm/arm64: Fix guest external abort matching
  KVM: PPC: Book3S HV: Fix memory leak in kvm_vm_ioctl_get_htab_fd
  KVM: s390: vsie: cleanup mcck reinjection
  KVM: s390: use WARN_ON_ONCE only for checking
  KVM: s390: guestdbg: fix range check
  KVM: PPC: Book3S HV: Report storage key support to userspace
  KVM: PPC: Book3S HV: Fix case where HDEC is treated as 32-bit on POWER9
  KVM: PPC: Book3S HV: Fix invalid use of register expression
  KVM: PPC: Book3S HV: Fix H_REGISTER_VPA VPA size validation
  KVM: PPC: Book3S HV: Fix setting of storage key in H_ENTER
  KVM: PPC: e500mc: Fix a NULL dereference
  KVM: PPC: e500: Fix some NULL dereferences on error
  KVM: PPC: Book3S HV: Protect updates to spapr_tce_tables list
  KVM: s390: we are always in czam mode
  KVM: s390: expose no-DAT to guest and migration support
  KVM: s390: sthyi: remove invalid guest write access
  ...
2017-09-08 15:18:36 -07:00
Ram Pai
d182b8fd60 KVM: PPC: Book3S HV: Fix setting of storage key in H_ENTER
In handling a H_ENTER hypercall, the code in kvmppc_do_h_enter
clobbers the high-order two bits of the storage key, which is stored
in a split field in the second doubleword of the HPTE.  Any storage
key number above 7 hence fails to operate correctly.

This makes sure we preserve all the bits of the storage key.

Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-08-31 12:36:44 +10:00
Aneesh Kumar K.V
79cc38ded1 powerpc/mm/hugetlb: Add support for reserving gigantic huge pages via kernel command line
With commit aa888a7497 ("hugetlb: support larger than MAX_ORDER") we added
support for allocating gigantic hugepages via kernel command line. Switch
ppc64 arch specific code to use that.

W.r.t FSL support, we now limit our allocation range using BOOTMEM_ALLOC_ACCESSIBLE.

We use the kernel command line to do reservation of hugetlb pages on powernv
platforms. On pseries hash mmu mode the supported gigantic huge page size is
16GB and that can only be allocated with hypervisor assist. For pseries the
command line option doesn't do the allocation. Instead pseries does gigantic
hugepage allocation based on hypervisor hint that is specified via
"ibm,expected#pages" property of the memory node.

Cc: Scott Wood <oss@buserror.net>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16 14:56:12 +10:00
Michael Ellerman
add2e1e585 powerpc/mm/hash: Fix off-by-one in comment about kernel contexts ids
Michal Suchánek noticed a comment in book3s/64/mmu-hash.h about the context ids
we use for the kernel was inconsistent with the code and other comments in the
same file.

It should read 1-4 not 1-5.

While we're touching it, update "address" to "addresses" which makes more sense
as it's referring to more than one address below.

Reported-by: Michal Suchánek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28 22:02:55 +10:00
Aneesh Kumar K.V
82228e362f powerpc/pseries: Skip using reserved virtual address range
Now that we use all the available virtual address range, we need to make
sure we don't generate VSID such that it overlaps with the reserved vsid
range. Reserved vsid range include the virtual address range used by the
adjunct partition and also the VRMA virtual segment. We find the context
value that can result in generating such a VSID and reserve it early in
boot.

We don't look at the adjunct range, because for now we disable the
adjunct usage in a Linux LPAR via CAS interface.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Rewrite hash__reserve_context_id(), move the rest into pseries]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-01 21:12:27 +11:00
Aneesh Kumar K.V
957b778a16 powerpc/mm: Add addr_limit to mm_context and use it to derive max slice index
In the followup patch, we will increase the slice array size to handle
512TB range, but will limit the max addr to 128TB. Avoid doing
unnecessary computation and avoid doing slice mask related operation
above address limit.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-01 21:12:20 +11:00
Aneesh Kumar K.V
59248aecc4 powerpc/mm/hash: Convert mask to unsigned long
This doesn't have any functional change. But helps in avoiding mistakes
in case the shift bit changes

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31 23:10:00 +11:00
Aneesh Kumar K.V
e6f81a9201 powerpc/mm/hash: Support 68 bit VA
Inorder to support large effective address range (512TB), we want to
increase the virtual address bits to 68. But we do have platforms like
p4 and p5 that can only do 65 bit VA. We support those platforms by
limiting context bits on them to 16.

The protovsid -> vsid conversion is verified to work with both 65 and 68
bit va values. I also documented the restrictions in a table format as
part of code comments.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31 23:10:00 +11:00
Michael Ellerman
85beb1c486 powerpc/mm/hash: Check for non-kernel address in get_kernel_vsid()
get_kernel_vsid() has a very stern comment saying that it's only valid
for kernel addresses, but there's nothing in the code to enforce that.

Rather than hoping our callers are well behaved, add a check and return
a VSID of 0 (invalid).

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31 23:09:59 +11:00
Aneesh Kumar K.V
941711a3a0 powerpc/mm/hash: Use context ids 1-4 for the kernel
Currently we use the top 4 context ids (0x7fffc-0x7ffff) for the kernel.
Kernel VSIDs are built using these top context values and effective the
segement ID. In subsequent patches we want to increase the max effective
address to 512TB. We will achieve that by increasing the effective
segment IDs there by increasing virtual address range.

We will be switching to a 68bit virtual address in the following patch.
But platforms like Power4 and Power5 only support a 65 bit virtual
address. We will handle that by limiting the context bits to 16 instead
of 19 on those platforms. That means the max context id will have a
different value on different platforms.

So that we don't have to deal with the kernel context ids changing
between different platforms, move the kernel context ids down to use
context ids 1-4.

We can't use segment 0 of context-id 0, because that maps to VSID 0,
which we want to keep as invalid, so we avoid context-id 0 entirely.
Similarly we can't use the last segment of the maximum context, so we
avoid it too.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Switch from 0-3 to 1-4 so VSID=0 remains invalid]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31 23:09:59 +11:00
David Gibson
dbcf929c00 powerpc/pseries: Add support for hash table resizing
This adds support for using two hypercalls to change the size of the
main hash page table while running as a PAPR guest. For now these
hypercalls are only in experimental qemu versions.

The interface is two part: first H_RESIZE_HPT_PREPARE is used to
allocate and prepare the new hash table. This may be slow, but can be
done asynchronously. Then, H_RESIZE_HPT_COMMIT is used to switch to the
new hash table. This requires that no CPUs be concurrently updating the
HPT, and so must be run under stop_machine().

This also adds a debugfs file which can be used to manually control
HPT resizing or testing purposes.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Paul Mackerras <paulus@samba.org>
[mpe: Rename the debugfs file to "hpt_order"]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-10 13:27:55 +11:00
Aneesh Kumar K.V
79270e0a3f powerpc/mm/hash: Properly mask the ESID bits when building proto VSID
The proto VSID is built using both the MMU context id and effective
segment ID (ESID). We should not have overlapping bits between those.
That could result in us having a VSID collision. With the current code
we missed masking the top bits of the ESID. This implies for kernel
address we ended up using the top 4 bits of the ESID as part of the
proto VSID, which is wrong.

The current code use the top 4 context values (0x7fffc - 0x7ffff) for
the kernel. With those context IDs used for the kernel, we don't run
into VSID collisions because we get the same proto VSID irrespective of
whether we mask the ESID bits or not. eg:

  ea         = 0xf000000000000000
  context    = 0x7ffff

  w/out masking:
  proto_vsid = (0x7ffff << 6 | 0xf000000000000000 >> 40)
	     = (0x1ffffc0 | 0xf00000)
	     =  0x1ffffc0

  with masking:
  proto_vsid = (0x7ffff << 6 | ((0xf000000000000000 >> 40) & 0x3f))
	     = (0x1ffffc0 | (0xf00000 & 0x3f))
	     =  0x1ffffc0 | 0)
	     =  0x1ffffc0

So although there is no bug, the code is still overly subtle, so fix it
to save ourselves pain in future.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-30 16:34:50 +11:00