Add a new mode to only print metrics. Sometimes we don't care about the
raw values, just want the computed metrics. This allows more compact
printing, so with -I each sample is only a single line. This also
allows easier plotting and processing with other tools.
The main target is with using --topdown, but it also works with -T and
standard perf stat. A few metrics are not supported.
To avoiding having to hardcode all the metrics in the code it uses a two
pass approach: first compute dummy metrics and only print the headers in
the print_metric callback. Then use the callback to print the actual
values.
There are some additional changes in the stat printout code to handle
all metrics being on a single line.
One issue is that the column code doesn't know in advance what events
are not supported by the CPU, and it would be hard to find out as this
could change based on dynamic conditions. That causes empty columns in
some cases.
The output can be fairly wide, often you may need more than 80 columns.
Example:
% perf stat -a -I 1000 --metric-only
1.001452803 frontend cycles idle insn per cycle stalled cycles per insn branch-misses of all branches
1.001452803 158.91% 0.66 2.39 2.92%
2.002192321 180.63% 0.76 2.08 2.96%
3.003088282 150.59% 0.62 2.57 2.84%
4.004369835 196.20% 0.98 1.62 3.79%
5.005227314 231.98% 0.84 1.90 4.71%
v2: Lots of updates.
v3: Use slightly narrower columns
v4: Add comment
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1457049458-28956-6-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
With all the recently added fields in the perf stat CSV output we should
finally document them in the man page. Do this here.
v2: Fix fields in documentation (Jiri)
v3: fix order of fields again (Jiri)
v4: Change order again.
v5: Document more fields (Jiri)
v6: Move time stamp first
v7: More fixes (Jiri)
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1457049458-28956-5-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The context menu in TUI hists browser checks corresponding sort keys
when creating the menu item. But hotkey actions lacks these checks so
it can filter using incorrect info.
For example, default sort key of 'perf top' doesn't contain 'comm' or
'pid' sort key so each hist entry's thread info is not reliable. Thus
it should prohibit using thread filter on 't' key.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1457533253-21419-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The commit 2eafd410e6 ("perf hists browser: Only 'Zoom into thread'
only when sort order has 'pid'") disabled thread filtering in hist
browser for the default sort key. However the he->thread is still valid
even if 'pid' sort key is not given. Only thing it should not use is
the pid (or tid) of the thread. So allow to filter by thread when
'comm' sort key is given and show pid only if 'pid' sort key is given.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1457536490-24084-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The sort__has_comm variable is to check whether the comm sort key is
given. This is necessary to support thread filtering in the TUI hists
browser later.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1457533253-21419-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When hierarchy mode is enabled, each entry in a hierarchy level shares
the period. IOW an upper level entry's period is the sum of lower level
entries. Thus perf uses only one of them to calculate the total period
of hists. It was lowest-level (leaf) entries but it has a problem when
it comes to filters.
If a filter is applied, entries in the same level will be filtered or
not. But upper level entries still have period of their sum including
filtered one. So total sum of upper level entries will not be same as
sum of lower level entries.
This resulted in entries having more than 100% of overhead and it can be
produced using perf top with filter(s).
Reported-and-Tested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-8-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The nr_sort_keys field is to carry the number of sort entries in a
hpp_list or hists to determine the depth of indentation of a hist entry.
As it's only used in hierarchy mode and now we have used nr_hpp_node for
this reason, there's no need to keep it anymore. Let's get rid of it.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-7-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The hist_browser__fprintf_hierarchy_entry() if to dump current output
into a file so it needs to be sync-ed with the corresponding function
hist_browser__show_hierarchy_entry(). So use hists->nr_hpp_node to
indent width and use first fmt_node to print overhead columns instead of
checking whether it's a sort entry (or dynamic entry).
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-6-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It's not used anymore and the output format is accessed by the hpp_list
pointer instead when hierarchy is enabled. Let's get rid of it.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-5-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When a command-line filter is applied in hierarchy mode, output is
broken especially when filtering on lower level. The higher level
entries doesn't show up so it's hard to see the results.
Also it needs to handle multi sort keys in a single hierarchy level.
Before:
$ perf report --hierarchy -s 'cpu,{dso,comm}' --comms swapper --stdio
...
# Overhead CPU / Shared Object+Command
# ........... ...........................
#
13.79% [kernel.vmlinux] swapper
31.71% 000
13.80% [kernel.vmlinux] swapper
0.43% [e1000e] swapper
11.89% [kernel.vmlinux] swapper
9.18% [kernel.vmlinux] swapper
After:
# Overhead CPU / Shared Object+Command
# ........... ...............................
#
33.09% 003
13.79% [kernel.vmlinux] swapper
31.71% 000
13.80% [kernel.vmlinux] swapper
0.43% [e1000e] swapper
21.90% 002
11.89% [kernel.vmlinux] swapper
13.30% 001
9.18% [kernel.vmlinux] swapper
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Those functions are for checkinf if a given perf_hpp_fmt is a
filter-related sort entry. With hierarchy mode, it needs to check
filters on the hist entries with its own hpp format list.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When hierarchy mode is enabled each output format is in a separate hpp
list. So when applying a filter it should check all formats in the
list. Currently it only checks a single ->fmt field which was not set
properly.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457531222-18130-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Build jitdump only on architectures defined in util/genelf.h file, to avoid
breaking the build on such arches.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dbueso@suse.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Mel Gorman <mgorman@suse.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20160310164113.GA11357@krava.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add myself as the maintainer of the NAND subsystem.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Richard Weinberger <richard@nod.at>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
is a bit larger because the surrounding code needed a cleanup, but
nothing worrisome.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"A few simple fixes for ARM, x86, PPC and generic code.
The x86 MMU fix is a bit larger because the surrounding code needed a
cleanup, but nothing worrisome"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: MMU: fix reserved bit check for ept=0/CR0.WP=0/CR4.SMEP=1/EFER.NX=0
KVM: MMU: fix ept=0/pte.u=1/pte.w=0/CR0.WP=0/CR4.SMEP=1/EFER.NX=0 combo
kvm: cap halt polling at exactly halt_poll_ns
KVM: s390: correct fprs on SIGP (STOP AND) STORE STATUS
KVM: VMX: disable PEBS before a guest entry
KVM: PPC: Book3S HV: Sanitize special-purpose register values on guest exit
- Temporarily disable huge pages built using contiguous ptes
- Ensure vmemmap region is sufficiently aligned for sparsemem sections
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"I thought we were done for 4.5, but then the 64k-page chaps came
crawling out of the woodwork. *sigh*
The vmemmap fix I sent for -rc7 caused a regression with 64k pages and
sparsemem and at some point during the release cycle the new hugetlb
code using contiguous ptes started failing the libhugetlbfs tests with
64k pages enabled.
So here are a couple of patches that fix the vmemmap alignment and
disable the new hugetlb page sizes whilst a proper fix is being
developed:
- Temporarily disable huge pages built using contiguous ptes
- Ensure vmemmap region is sufficiently aligned for sparsemem
sections"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: hugetlb: partial revert of 66b3923a1a
arm64: account for sparsemem section alignment when choosing vmemmap offset
Pull s390 fixes from Martin Schwidefsky:
"Three bug fixes:
- The fix for the page table corruption (CVE-2016-2143)
- The diagnose statistics introduced a regression for the dasd diag
driver
- Boot crash on systems without the set-program-parameters facility"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/mm: four page table levels vs. fork
s390/cpumf: Fix lpp detection
s390/dasd: fix diag 0x250 inline assembly
The legacy media controller userspace API exposes entity types that
carry both type and function information. The new API replaces the type
with a function. It preserves backward compatibility by defining legacy
functions for the existing types and using them in drivers.
This works fine, as long as newer entity functions won't be added.
Unfortunately, some tools, like media-ctl with --print-dot argument
rely on the now legacy MEDIA_ENT_T_V4L2_SUBDEV and MEDIA_ENT_T_DEVNODE
numeric ranges to identify what entities will be shown.
Also, if the entity doesn't match those ranges, it will ignore the
major/minor information on devnodes, and won't be getting the devnode
name via udev or sysfs.
As we're now adding devices outside the old range, the legacy ioctl
needs to map the new entity functions into a type at the old range,
or otherwise we'll have a regression.
Detected on all released media-ctl versions (e. g. versions <= 1.10).
Fix this by deriving the type from the function to emulate the legacy
API if the function isn't in the legacy functions range.
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Large memory Haswell-EX systems with multiple DIMMs per channel were
sometimes reporting the wrong DIMM.
Found three problems:
1) Debug printouts for socket and channel interleave were not interpreting
the register fields correctly. The socket interleave field is a 2^X
value (0=1, 1=2, 2=4, 3=8). The channel interleave is X+1 (0=1, 1=2,
2=3. 3=4).
2) Actual use of the socket interleave value didn't interpret as 2^X
3) Conversion of address to channel address was complicated, and wrong.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Aristeu Rozanski <arozansk@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-edac@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When computing the residue we need two pieces of information: the current
descriptor and the remaining data of the current descriptor. To get
that information, we need to read consecutively two registers but we
can't do it in an atomic way. For that reason, we have to check manually
that current descriptor has not changed.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Suggested-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Reported-by: David Engraf <david.engraf@sysgo.com>
Tested-by: David Engraf <david.engraf@sysgo.com>
Fixes: e1f7c9eee7 ("dmaengine: at_xdmac: creation of the atmel
eXtended DMA Controller driver")
Cc: stable@vger.kernel.org #4.1 and later
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
We do use this_cpu_ptr(&cpu_tss) as a cacheline-aligned, seldomly
accessed per-cpu var as the MONITORX target in delay_mwaitx(). However,
when called in preemptible context, this_cpu_ptr -> smp_processor_id() ->
debug_smp_processor_id() fires:
BUG: using smp_processor_id() in preemptible [00000000] code: udevd/312
caller is delay_mwaitx+0x40/0xa0
But we don't care about that check - we only need cpu_tss as a MONITORX
target and it doesn't really matter which CPU's var we're touching as
we're going idle anyway. Fix that.
Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: spg_linux_kernel@amd.com
Link: http://lkml.kernel.org/r/20160309205622.GG6564@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
KVM has special logic to handle pages with pte.u=1 and pte.w=0 when
CR0.WP=1. These pages' SPTEs flip continuously between two states:
U=1/W=0 (user and supervisor reads allowed, supervisor writes not allowed)
and U=0/W=1 (supervisor reads and writes allowed, user writes not allowed).
When SMEP is in effect, however, U=0 will enable kernel execution of
this page. To avoid this, KVM also sets NX=1 in the shadow PTE together
with U=0, making the two states U=1/W=0/NX=gpte.NX and U=0/W=1/NX=1.
When guest EFER has the NX bit cleared, the reserved bit check thinks
that the latter state is invalid; teach it that the smep_andnot_wp case
will also use the NX bit of SPTEs.
Cc: stable@vger.kernel.org
Reviewed-by: Xiao Guangrong <guangrong.xiao@linux.inel.com>
Fixes: c258b62b26
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Yes, all of these are needed. :) This is admittedly a bit odd, but
kvm-unit-tests access.flat tests this if you run it with "-cpu host"
and of course ept=0.
KVM runs the guest with CR0.WP=1, so it must handle supervisor writes
specially when pte.u=1/pte.w=0/CR0.WP=0. Such writes cause a fault
when U=1 and W=0 in the SPTE, but they must succeed because CR0.WP=0.
When KVM gets the fault, it sets U=0 and W=1 in the shadow PTE and
restarts execution. This will still cause a user write to fault, while
supervisor writes will succeed. User reads will fault spuriously now,
and KVM will then flip U and W again in the SPTE (U=1, W=0). User reads
will be enabled and supervisor writes disabled, going back to the
originary situation where supervisor writes fault spuriously.
When SMEP is in effect, however, U=0 will enable kernel execution of
this page. To avoid this, KVM also sets NX=1 in the shadow PTE together
with U=0. If the guest has not enabled NX, the result is a continuous
stream of page faults due to the NX bit being reserved.
The fix is to force EFER.NX=1 even if the CPU is taking care of the EFER
switch. (All machines with SMEP have the CPU_LOAD_IA32_EFER vm-entry
control, so they do not use user-return notifiers for EFER---if they did,
EFER.NX would be forced to the same value as the host).
There is another bug in the reserved bit check, which I've split to a
separate patch for easier application to stable kernels.
Cc: stable@vger.kernel.org
Cc: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Fixes: f6577a5fa1
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We can micro-optimize this call and mildly relax the
barrier requirements by relying on ctrl + rmb, keeping
the acquire semantics. In addition, this is pretty much
the now standard for busy-waiting under such restraints.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave@stgolabs.net
Link: http://lkml.kernel.org/r/1457574936-19065-3-git-send-email-dbueso@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While the compiler tends to already to it for us (except for
csd_unlock), make it explicit. These helpers mainly deal with
the ->flags, are short-lived and can be called, for example,
from smp_call_function_many().
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave@stgolabs.net
Link: http://lkml.kernel.org/r/1457574936-19065-2-git-send-email-dbueso@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Leonid Shatz noticed that the SDM interpretation of the following
recent commit:
394db20ca2 ("x86/fpu: Disable AVX when eagerfpu is off")
... is incorrect and that the original behavior of the FPU code was correct.
Because AVX is not stated in CR0 TS bit description, it was mistakenly
believed to be not supported for lazy context switch. This turns out
to be false:
Intel Software Developer's Manual Vol. 3A, Sec. 2.5 Control Registers:
'TS Task Switched bit (bit 3 of CR0) -- Allows the saving of the x87 FPU/
MMX/SSE/SSE2/SSE3/SSSE3/SSE4 context on a task switch to be delayed until
an x87 FPU/MMX/SSE/SSE2/SSE3/SSSE3/SSE4 instruction is actually executed
by the new task.'
Intel Software Developer's Manual Vol. 2A, Sec. 2.4 Instruction Exception
Specification:
'AVX instructions refer to exceptions by classes that include #NM
"Device Not Available" exception for lazy context switch.'
So revert the commit.
Reported-by: Leonid Shatz <leonid.shatz@ravellosystems.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1457569734-3785-1-git-send-email-yu-cheng.yu@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The fork of a process with four page table levels is broken since
git commit 6252d702c5 "[S390] dynamic page tables."
All new mm contexts are created with three page table levels and
an asce limit of 4TB. If the parent has four levels dup_mmap will
add vmas to the new context which are outside of the asce limit.
The subsequent call to copy_page_range will walk the three level
page table structure of the new process with non-zero pgd and pud
indexes. This leads to memory clobbers as the pgd_index *and* the
pud_index is added to the mm->pgd pointer without a pgd_deref
in between.
The init_new_context() function is selecting the number of page
table levels for a new context. The function is used by mm_init()
which in turn is called by dup_mm() and mm_alloc(). These two are
used by fork() and exec(). The init_new_context() function can
distinguish the two cases by looking at mm->context.asce_limit,
for fork() the mm struct has been copied and the number of page
table levels may not change. For exec() the mm_alloc() function
set the new mm structure to zero, in this case a three-level page
table is created as the temporary stack space is located at
STACK_TOP_MAX = 4TB.
This fixes CVE-2016-2143.
Reported-by: Marcin Kościelnicki <koriakin@0x04.net>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
A few driver specific fixes for the Rockchip and i.MX SPI controllers,
especially for the i.MX they're annoying bugs if you run into them.
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Merge tag 'spi-fix-v4.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown:
"A few driver specific fixes for the Rockchip and i.MX SPI controllers,
especially for the i.MX they're annoying bugs if you run into them"
* tag 'spi-fix-v4.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: imx: fix spi resource leak with dma transfer
spi: imx: allow only WML aligned transfers to use DMA
spi: rockchip: add missing spi_master_put
spi: rockchip: disable runtime pm when in err case
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fix from Ted Ts'o:
"This fixes a regression which crept in v4.5-rc5"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: iterate over buffer heads correctly in move_extent_per_page()
Pull drm fixes from Dave Airlie:
"A few imx fixes I missed from a couple of weeks ago, they still aren't
that big and fix some regression and a fail to boot problem.
Other than that, a couple of regression fixes for radeon/amdgpu, one
regression fix for vmwgfx and one regression fix for tda998x"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
Revert "drm/radeon/pm: adjust display configuration after powerstate"
drm/amdgpu/dp: add back special handling for NUTMEG
drm/radeon/dp: add back special handling for NUTMEG
drm/i2c: tda998x: Choose between atomic or non atomic dpms helper
drm/vmwgfx: Add back ->detect() and ->fill_modes()
drm/radeon: Fix error handling in radeon_flip_work_func.
drm/amdgpu: Fix error handling in amdgpu_flip_work_func.
drm/imx: Add missing DRM_FORMAT_RGB565 to ipu_plane_formats
drm/imx: notify DRM core about CRTC vblank state
gpu: ipu-v3: Reset IPU before activating IRQ
gpu: ipu-v3: Do not bail out on missing optional port nodes
if the current cpu is offline. But I forgot that in 3.18, we added lockdep
checks to test RCU usage even when the event is disabled. Although there
cannot be any bug when a cpu is going offline, we now get false warnings
triggered by the added checks of the event being disabled.
I removed the check from the tracepoint code itself, and added it to the
condition section (which is "1" for 'no condition'). This way the online
cpu check will get checked in all the right locations.
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Merge tag 'trace-fixes-v4.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"I previously sent a fix that prevents all trace events from being
called if the current cpu is offline.
But I forgot that in 3.18, we added lockdep checks to test RCU usage
even when the event is disabled. Although there cannot be any bug
when a cpu is going offline, we now get false warnings triggered by
the added checks of the event being disabled.
I removed the check from the tracepoint code itself, and added it to
the condition section (which is "1" for 'no condition'). This way the
online cpu check will get checked in all the right locations"
* tag 'trace-fixes-v4.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix check for cpu online when event is disabled
In commit bcff24887d ("ext4: don't read blocks from disk after extents
being swapped") bh is not updated correctly in the for loop and wrong
data has been written to disk. generic/324 catches this on sub-page
block size ext4.
Fixes: bcff24887d ("ext4: don't read blocks from disk after extentsbeing swapped")
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Merge fixes from Andrew Morton:
"13 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
dma-mapping: avoid oops when parameter cpu_addr is null
mm/hugetlb: use EOPNOTSUPP in hugetlb sysctl handlers
memremap: check pfn validity before passing to pfn_to_page()
mm, thp: fix migration of PTE-mapped transparent huge pages
dax: check return value of dax_radix_entry()
ocfs2: fix return value from ocfs2_page_mkwrite()
arm64: kasan: clear stale stack poison
sched/kasan: remove stale KASAN poison after hotplug
kasan: add functions to clear stack poison
mm: fix mixed zone detection in devm_memremap_pages
list: kill list_force_poison()
mm: __delete_from_page_cache show Bad page if mapped
mm/hugetlb: hugetlb_no_page: rate-limit warning message
To keep consistent with kfree, which tolerate ptr is NULL. We do this
because sometimes we may use goto statement, so that success and failure
case can share parts of the code. But unfortunately, dma_free_coherent
called with parameter cpu_addr is null will cause oops, such as showed
below:
Unable to handle kernel paging request at virtual address ffffffc020d3b2b8
pgd = ffffffc083a61000
[ffffffc020d3b2b8] *pgd=0000000000000000, *pud=0000000000000000
CPU: 4 PID: 1489 Comm: malloc_dma_1 Tainted: G O 4.1.12 #1
Hardware name: ARM64 (DT)
PC is at __dma_free_coherent.isra.10+0x74/0xc8
LR is at __dma_free+0x9c/0xb0
Process malloc_dma_1 (pid: 1489, stack limit = 0xffffffc0837fc020)
[...]
Call trace:
__dma_free_coherent.isra.10+0x74/0xc8
__dma_free+0x9c/0xb0
malloc_dma+0x104/0x158 [dma_alloc_coherent_mtmalloc]
kthread+0xec/0xfc
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace ENOTSUPP with EOPNOTSUPP. If hugepages are not supported, this
value is propagated to userspace. EOPNOTSUPP is part of uapi and is
widely supported by libc libraries.
It gives nicer message to user, rather than:
# cat /proc/sys/vm/nr_hugepages
cat: /proc/sys/vm/nr_hugepages: Unknown error 524
And also LTP's proc01 test was failing because this ret code (524)
was unexpected:
proc01 1 TFAIL : proc01.c:396: read failed: /proc/sys/vm/nr_hugepages: errno=???(524): Unknown error 524
proc01 2 TFAIL : proc01.c:396: read failed: /proc/sys/vm/nr_hugepages_mempolicy: errno=???(524): Unknown error 524
proc01 3 TFAIL : proc01.c:396: read failed: /proc/sys/vm/nr_overcommit_hugepages: errno=???(524): Unknown error 524
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In memremap's helper function try_ram_remap(), we dereference a struct
page pointer that was derived from a PFN that is known to be covered by
a 'System RAM' iomem region, and is thus assumed to be a 'valid' PFN,
i.e., a PFN that has a struct page associated with it and is covered by
the kernel direct mapping.
However, the assumption that there is a 1:1 relation between the System
RAM iomem region and the kernel direct mapping is not universally valid
on all architectures, and on ARM and arm64, 'System RAM' may include
regions for which pfn_valid() returns false.
Generally speaking, both __va() and pfn_to_page() should only ever be
called on PFNs/physical addresses for which pfn_valid() returns true, so
add that check to try_ram_remap().
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We don't have native support of THP migration, so we have to split huge
page into small pages in order to migrate it to different node. This
includes PTE-mapped huge pages.
I made mistake in refcounting patchset: we don't actually split
PTE-mapped huge page in queue_pages_pte_range(), if we step on head
page.
The result is that the head page is queued for migration, but none of
tail pages: putting head page on queue takes pin on the page and any
subsequent attempts of split_huge_pages() would fail and we skip queuing
tail pages.
unmap_and_move_huge_page() will eventually split the huge pages, but
only one of 512 pages would get migrated.
Let's fix the situation.
Fixes: 248db92da1 ("migrate_pages: try to split pages on queuing")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dax_pfn_mkwrite() previously wasn't checking the return value of the
call to dax_radix_entry(), which was a mistake.
Instead, capture this return value and return the appropriate VM_FAULT_
value.
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ocfs2_page_mkwrite() could mistakenly return error code instead of
mkwrite status value. Fix it.
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Functions which the compiler has instrumented for KASAN place poison on
the stack shadow upon entry and remove this poison prior to returning.
In the case of cpuidle, CPUs exit the kernel a number of levels deep in
C code. Any instrumented functions on this critical path will leave
portions of the stack shadow poisoned.
If CPUs lose context and return to the kernel via a cold path, we
restore a prior context saved in __cpu_suspend_enter are forgotten, and
we never remove the poison they placed in the stack shadow area by
functions calls between this and the actual exit of the kernel.
Thus, (depending on stackframe layout) subsequent calls to instrumented
functions may hit this stale poison, resulting in (spurious) KASAN
splats to the console.
To avoid this, clear any stale poison from the idle thread for a CPU
prior to bringing a CPU online.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Functions which the compiler has instrumented for KASAN place poison on
the stack shadow upon entry and remove this poision prior to returning.
In the case of CPU hotplug, CPUs exit the kernel a number of levels deep
in C code. Any instrumented functions on this critical path will leave
portions of the stack shadow poisoned.
When a CPU is subsequently brought back into the kernel via a different
path, depending on stackframe, layout calls to instrumented functions
may hit this stale poison, resulting in (spurious) KASAN splats to the
console.
To avoid this, clear any stale poison from the idle thread for a CPU
prior to bringing a CPU online.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Functions which the compiler has instrumented for ASAN place poison on
the stack shadow upon entry and remove this poison prior to returning.
In some cases (e.g. hotplug and idle), CPUs may exit the kernel a
number of levels deep in C code. If there are any instrumented
functions on this critical path, these will leave portions of the idle
thread stack shadow poisoned.
If a CPU returns to the kernel via a different path (e.g. a cold
entry), then depending on stack frame layout subsequent calls to
instrumented functions may use regions of the stack with stale poison,
resulting in (spurious) KASAN splats to the console.
Contemporary GCCs always add stack shadow poisoning when ASAN is
enabled, even when asked to not instrument a function [1], so we can't
simply annotate functions on the critical path to avoid poisoning.
Instead, this series explicitly removes any stale poison before it can
be hit. In the common hotplug case we clear the entire stack shadow in
common code, before a CPU is brought online.
On architectures which perform a cold return as part of cpu idle may
retain an architecture-specific amount of stack contents. To retain the
poison for this retained context, the arch code must call the core KASAN
code, passing a "watermark" stack pointer value beyond which shadow will
be cleared. Architectures which don't perform a cold return as part of
idle do not need any additional code.
This patch (of 3):
Functions which the compiler has instrumented for KASAN place poison on
the stack shadow upon entry and remove this poision prior to returning.
In some cases (e.g. hotplug and idle), CPUs may exit the kernel a number
of levels deep in C code. If there are any instrumented functions on this
critical path, these will leave portions of the stack shadow poisoned.
If a CPU returns to the kernel via a different path (e.g. a cold entry),
then depending on stack frame layout subsequent calls to instrumented
functions may use regions of the stack with stale poison, resulting in
(spurious) KASAN splats to the console.
To avoid this, we must clear stale poison from the stack prior to
instrumented functions being called. This patch adds functions to the
KASAN core for removing poison from (portions of) a task's stack. These
will be used by subsequent patches to avoid problems with hotplug and
idle.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The check for whether we overlap "System RAM" needs to be done at
section granularity. For example a system with the following mapping:
100000000-37bffffff : System RAM
37c000000-837ffffff : Persistent Memory
...is unable to use devm_memremap_pages() as it would result in two
zones colliding within a given section.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Given we have uninitialized list_heads being passed to list_add() it
will always be the case that those uninitialized values randomly trigger
the poison value. Especially since a list_add() operation will seed the
stack with the poison value for later stack allocations to trip over.
For example, see these two false positive reports:
list_add attempted on force-poisoned entry
WARNING: at lib/list_debug.c:34
[..]
NIP [c00000000043c390] __list_add+0xb0/0x150
LR [c00000000043c38c] __list_add+0xac/0x150
Call Trace:
__list_add+0xac/0x150 (unreliable)
__down+0x4c/0xf8
down+0x68/0x70
xfs_buf_lock+0x4c/0x150 [xfs]
list_add attempted on force-poisoned entry(0000000000000500),
new->next == d0000000059ecdb0, new->prev == 0000000000000500
WARNING: at lib/list_debug.c:33
[..]
NIP [c00000000042db78] __list_add+0xa8/0x140
LR [c00000000042db74] __list_add+0xa4/0x140
Call Trace:
__list_add+0xa4/0x140 (unreliable)
rwsem_down_read_failed+0x6c/0x1a0
down_read+0x58/0x60
xfs_log_commit_cil+0x7c/0x600 [xfs]
Fixes: commit 5c2c2587b1 ("mm, dax, pmem: introduce {get|put}_dev_pagemap() for dax-gup")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Eryu Guan <eguan@redhat.com>
Tested-by: Eryu Guan <eguan@redhat.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit e1534ae950 ("mm: differentiate page_mapped() from
page_mapcount() for compound pages") changed the famous
BUG_ON(page_mapped(page)) in __delete_from_page_cache() to
VM_BUG_ON_PAGE(page_mapped(page)): which gives us more info when
CONFIG_DEBUG_VM=y, but nothing at all when not.
Although it has not usually been very helpul, being hit long after the
error in question, we do need to know if it actually happens on users'
systems; but reinstating a crash there is likely to be opposed :)
In the non-debug case, pr_alert("BUG: Bad page cache") plus dump_page(),
dump_stack(), add_taint() - I don't really believe LOCKDEP_NOW_UNRELIABLE,
but that seems to be the standard procedure now. Move that, or the
VM_BUG_ON_PAGE(), up before the deletion from tree: so that the
unNULLified page->mapping gives a little more information.
If the inode is being evicted (rather than truncated), it won't have any
vmas left, so it's safe(ish) to assume that the raised mapcount is
erroneous, and we can discount it from page_count to avoid leaking the
page (I'm less worried by leaking the occasional 4kB, than losing a
potential 2MB page with each 4kB page leaked).
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.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>
The warning message "killed due to inadequate hugepage pool" simply
indicates that SIGBUS was sent, not that the process was forcibly killed.
If the process has a signal handler installed does not fix the problem,
this message can rapidly spam the kernel log.
On my amd64 dev machine that does not have hugepages configured, I can
reproduce the repeated warnings easily by setting vm.nr_hugepages=2 (i.e.,
4 megabytes of huge pages) and running something that sets a signal
handler and forks, like
#include <sys/mman.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
sig_atomic_t counter = 10;
void handler(int signal)
{
if (counter-- == 0)
exit(0);
}
int main(void)
{
int status;
char *addr = mmap(NULL, 4 * 1048576, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, -1, 0);
if (addr == MAP_FAILED) {perror("mmap"); return 1;}
*addr = 'x';
switch (fork()) {
case -1:
perror("fork"); return 1;
case 0:
signal(SIGBUS, handler);
*addr = 'x';
break;
default:
*addr = 'x';
wait(&status);
if (WIFSIGNALED(status)) {
psignal(WTERMSIG(status), "child");
}
break;
}
}
Signed-off-by: Geoffrey Thomas <geofft@ldpreload.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
