Now we can use it with --overwrite to have a flight recorder mode that
gets snapshot requests from arbitrary events that are processed in the
side band thread together with the PERF_RECORD_BPF_EVENT processing.
Example:
To collect scheduler events until a recvmmsg syscall happens, system
wide:
[root@five a]# rm -f perf.data.2020042717*
[root@five a]# perf record --overwrite -e sched:*switch,syscalls:*recvmmsg --switch-output-event syscalls:sys_enter_recvmmsg
[ perf record: dump data: Woken up 1 times ]
[ perf record: Dump perf.data.2020042717585458 ]
[ perf record: dump data: Woken up 1 times ]
[ perf record: Dump perf.data.2020042717590235 ]
[ perf record: dump data: Woken up 1 times ]
[ perf record: Dump perf.data.2020042717590398 ]
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Dump perf.data.2020042717590511 ]
[ perf record: Captured and wrote 7.244 MB perf.data.<timestamp> ]
So in the above case we had 3 snapshots, the fourth was forced by
control+C:
One can make this more precise by adding the switch output event to the
main -e events list, as since this is done asynchronously, a few events
after the signal event will appear in the snapshots, as can be seen
with:
Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lore.kernel.org/lkml/20200429131106.27974-8-acme@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To register that an option was set, like with the upcoming 'perf record
--switch-output-option' one.
Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Link: http://lore.kernel.org/lkml/20200429131106.27974-7-acme@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf evlist: Allow reusing the side band thread for more purposes
I.e. so far we had just one event in that side band thread, a dummy one
with attr.bpf_event set, so that 'perf record' can go ahead and ask the
kernel for further information about BPF programs being loaded.
Allow for more than one event to be there, so that we can use it as
well for the upcoming --switch-output-event feature.
Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Link: http://lore.kernel.org/lkml/20200429131106.27974-6-acme@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf evlist: Move the sideband thread routines to separate object
To avoid dragging more stuff into the perf python binding in the
following csets.
Reported-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf parse-events: Add parse_events_option() variant that creates evlist
For the upcoming --switch-output-event option we want to create the side
band event, populate it with the specified events and then, if it is
present multiple times, go on adding to it, then, if the BPF tracking is
required, use the first event to set its attr.bpf_event to get those
PERF_RECORD_BPF_EVENT metadata events too.
Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Link: http://lore.kernel.org/lkml/20200429131106.27974-5-acme@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf bpf: Decouple creating the evlist from adding the SB event
Renaming bpf_event__add_sb_event() to evlist__add_sb_event() and
requiring that the evlist be allocated beforehand.
This will allow using the same side band thread and evlist to be used
for multiple purposes in addition to react to PERF_RECORD_BPF_EVENT soon
after they are generated.
Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Link: http://lore.kernel.org/lkml/20200429131106.27974-4-acme@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Where state related to a 'perf top' session is grouped.
Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Link: http://lore.kernel.org/lkml/20200429131106.27974-3-acme@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Where state related to a 'perf record' session is grouped.
Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Link: http://lore.kernel.org/lkml/20200429131106.27974-2-acme@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf tools: Move routines that probe for perf API features to separate file
Trying to disentangle this a bit further, unfortunately it uses
parse_events(), its interesting to have it separated anyway, so do it.
Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The hv_24×7 feature in IBM® POWER9™ processor-based servers provide the
facility to continuously collect large numbers of hardware performance
metrics efficiently and accurately.
This patch adds hv_24x7 metric file for different Socket/chip
resources.
Result:
power9 platform:
command:# ./perf stat --metric-only -M Memory_RD_BW_Chip -C 0 -I 1000
perf tools: Enable Hz/hz prinitg for --metric-only option
Commit 54b5091606c18 ("perf stat: Implement --metric-only mode") added
function 'valid_only_metric()' which drops "Hz" or "hz", if it is part
of "ScaleUnit". This patch enable it since hv_24x7 supports couple of
frequency events.
Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Joe Mario <jmario@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linuxppc-dev@lists.ozlabs.org Link: http://lore.kernel.org/lkml/20200401203340.31402-7-kjain@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf metricgroups: Enhance JSON/metric infrastructure to handle "?"
Patch enhances current metric infrastructure to handle "?" in the metric
expression. The "?" can be use for parameters whose value not known
while creating metric events and which can be replace later at runtime
to the proper value. It also add flexibility to create multiple events
out of single metric event added in JSON file.
Patch adds function 'arch_get_runtimeparam' which is a arch specific
function, returns the count of metric events need to be created. By
default it return 1.
This infrastructure needed for hv_24x7 socket/chip level events.
"hv_24x7" chip level events needs specific chip-id to which the data is
requested. Function 'arch_get_runtimeparam' implemented in header.c
which extract number of sockets from sysfs file "sockets" under
"/sys/devices/hv_24x7/interface/".
With this patch basically we are trying to create as many metric events
as define by runtime_param.
For that one loop is added in function 'metricgroup__add_metric', which
create multiple events at run time depend on return value of
'arch_get_runtimeparam' and merge that event in 'group_list'.
To achieve that we are actually passing this parameter value as part of
`expr__find_other` function and changing "?" present in metric
expression with this value.
As in our JSON file, there gonna be single metric event, and out of
which we are creating multiple events.
To understand which data count belongs to which parameter value,
we also printing param value in generic_metric function.
Zou Wei [Sun, 26 Apr 2020 12:38:03 +0000 (20:38 +0800)]
perf report: Fix warning assignment of 0/1 to bool variable
Fixes coccicheck warning:
tools/perf/builtin-report.c:1403:2-34: WARNING: Assignment of 0/1 to bool variable
Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zou Wei <zou_wei@huawei.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/1587904683-3510-1-git-send-email-zou_wei@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zou Wei <zou_wei@huawei.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/1588065523-71423-1-git-send-email-zou_wei@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zou Wei <zou_wei@huawei.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/1588064336-70456-1-git-send-email-zou_wei@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf script: Remove extraneous newline in perf_sample__fprintf_regs()
When printing iregs, there was a double newline printed because
perf_sample__fprintf_regs() was printing its own and then at the end of
all fields, perf script was adding one. This was causing blank line in
the output:
First we need to figure out how to request that registers be recorded,
so we use:
# perf record -h reg
Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
-I, --intr-regs[=<any register>]
sample selected machine registers on interrupt, use '-I?' to list register names
--buildid-all Record build-id of all DSOs regardless of hits
--user-regs[=<any register>]
sample selected machine registers on interrupt, use '--user-regs=?' to list register names
#
Ok, now lets ask for them all:
# perf record -a --intr-regs --user-regs sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 4.105 MB perf.data (2760 samples) ]
#
To see it more clearly, lets get just two of those registers by sample:
# perf record -a --intr-regs=ax,bx --user-regs=cx,dx sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 3.502 MB perf.data (1653 samples) ]
#
Extra info, lets see what gets setup in that 'struct perf_event_attr':
Cook, some PERF_SAMPLE_REGS_USER|PERF_SAMPLE_REGS_INTR +
attr.sample_regs_user and attr.sample_regs_intr register masks, now lets
see if those newlines are gone in a more compact fashion:
Ian Rogers [Wed, 15 Apr 2020 05:40:50 +0000 (22:40 -0700)]
perf synthetic events: Remove use of sscanf from /proc reading
The synthesize benchmark, run on a single process and thread, shows
perf_event__synthesize_mmap_events as the hottest function with fgets
and sscanf taking the majority of execution time.
fscanf performs similarly well. Replace the scanf call with manual
reading of each field of the /proc/pid/maps line, and remove some
unnecessary buffering.
This change also addresses potential, but unlikely, buffer overruns for
the string values read by scanf.
Performance before is:
$ sudo perf bench internals synthesize -m 16 -M 16 -s -t
\# Running 'internals/synthesize' benchmark:
Computing performance of single threaded perf event synthesis by
synthesizing events on the perf process itself:
Average synthesis took: 102.810 usec (+- 0.027 usec)
Average num. events: 17.000 (+- 0.000)
Average time per event 6.048 usec
Average data synthesis took: 106.325 usec (+- 0.018 usec)
Average num. events: 89.000 (+- 0.000)
Average time per event 1.195 usec
Computing performance of multi threaded perf event synthesis by
synthesizing events on CPU 0:
Number of synthesis threads: 16
Average synthesis took: 68103.100 usec (+- 441.234 usec)
Average num. events: 30703.000 (+- 0.730)
Average time per event 2.218 usec
And after is:
$ sudo perf bench internals synthesize -m 16 -M 16 -s -t
\# Running 'internals/synthesize' benchmark:
Computing performance of single threaded perf event synthesis by
synthesizing events on the perf process itself:
Average synthesis took: 50.388 usec (+- 0.031 usec)
Average num. events: 17.000 (+- 0.000)
Average time per event 2.964 usec
Average data synthesis took: 52.693 usec (+- 0.020 usec)
Average num. events: 89.000 (+- 0.000)
Average time per event 0.592 usec
Computing performance of multi threaded perf event synthesis by
synthesizing events on CPU 0:
Number of synthesis threads: 16
Average synthesis took: 45022.400 usec (+- 552.740 usec)
Average num. events: 30624.200 (+- 10.037)
Average time per event 1.470 usec
On a Intel Xeon 6154 compiling with Debian gcc 9.2.1.
Committer testing:
On a AMD Ryzen 5 3600X 6-Core Processor:
Before:
# perf bench internals synthesize --min-threads 12 --max-threads 12 --st --mt
# Running 'internals/synthesize' benchmark:
Computing performance of single threaded perf event synthesis by
synthesizing events on the perf process itself:
Average synthesis took: 267.491 usec (+- 0.176 usec)
Average num. events: 56.000 (+- 0.000)
Average time per event 4.777 usec
Average data synthesis took: 277.257 usec (+- 0.169 usec)
Average num. events: 287.000 (+- 0.000)
Average time per event 0.966 usec
Computing performance of multi threaded perf event synthesis by
synthesizing events on CPU 0:
Number of synthesis threads: 12
Average synthesis took: 81599.500 usec (+- 346.315 usec)
Average num. events: 36096.100 (+- 2.523)
Average time per event 2.261 usec
#
After:
# perf bench internals synthesize --min-threads 12 --max-threads 12 --st --mt
# Running 'internals/synthesize' benchmark:
Computing performance of single threaded perf event synthesis by
synthesizing events on the perf process itself:
Average synthesis took: 110.125 usec (+- 0.080 usec)
Average num. events: 56.000 (+- 0.000)
Average time per event 1.967 usec
Average data synthesis took: 118.518 usec (+- 0.057 usec)
Average num. events: 287.000 (+- 0.000)
Average time per event 0.413 usec
Computing performance of multi threaded perf event synthesis by
synthesizing events on CPU 0:
Number of synthesis threads: 12
Average synthesis took: 43490.700 usec (+- 284.527 usec)
Average num. events: 37028.500 (+- 0.563)
Average time per event 1.175 usec
#
Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-4-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ian Rogers [Wed, 15 Apr 2020 05:40:49 +0000 (22:40 -0700)]
tools api: Add a lightweight buffered reading api
The synthesize benchmark shows the majority of execution time going to
fgets and sscanf, necessary to parse /proc/pid/maps. Add a new buffered
reading library that will be used to replace these calls in a follow-up
CL. Add tests for the library to perf test.
Committer tests:
$ perf test api
63: Test api io : Ok
$
Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ian Rogers [Wed, 15 Apr 2020 05:40:48 +0000 (22:40 -0700)]
perf bench: Add a multi-threaded synthesize benchmark
By default this isn't run as it reads /proc and may not have access.
For consistency, modify the single threaded benchmark to compute an
average time per event.
-I, --multi-iterations <n>
Number of iterations used to compute multi-threaded average
-i, --single-iterations <n>
Number of iterations used to compute single-threaded average
-M, --max-threads <n>
Maximum number of threads in multithreaded bench
-m, --min-threads <n>
Minimum number of threads in multithreaded bench
-s, --st Run single threaded benchmark
-t, --mt Run multi-threaded benchmark
$
$ perf bench internals synthesize -t
# Running 'internals/synthesize' benchmark:
Computing performance of multi threaded perf event synthesis by
synthesizing events on CPU 0:
Number of synthesis threads: 1
Average synthesis took: 65449.000 usec (+- 586.442 usec)
Average num. events: 9405.400 (+- 0.306)
Average time per event 6.959 usec
Number of synthesis threads: 2
Average synthesis took: 37838.300 usec (+- 130.259 usec)
Average num. events: 9501.800 (+- 20.469)
Average time per event 3.982 usec
Number of synthesis threads: 3
Average synthesis took: 48551.400 usec (+- 225.686 usec)
Average num. events: 9544.000 (+- 0.000)
Average time per event 5.087 usec
Number of synthesis threads: 4
Average synthesis took: 29632.500 usec (+- 50.808 usec)
Average num. events: 9544.000 (+- 0.000)
Average time per event 3.105 usec
Number of synthesis threads: 5
Average synthesis took: 33920.400 usec (+- 284.509 usec)
Average num. events: 9544.000 (+- 0.000)
Average time per event 3.554 usec
Number of synthesis threads: 6
Average synthesis took: 27604.100 usec (+- 72.344 usec)
Average num. events: 9548.000 (+- 0.000)
Average time per event 2.891 usec
Number of synthesis threads: 7
Average synthesis took: 25406.300 usec (+- 933.371 usec)
Average num. events: 9545.500 (+- 0.167)
Average time per event 2.662 usec
Number of synthesis threads: 8
Average synthesis took: 24110.400 usec (+- 73.229 usec)
Average num. events: 9551.000 (+- 0.000)
Average time per event 2.524 usec
$
Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrey Zhizhikin <andrey.z@gmail.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200415054050.31645-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To control degree of parallelism of the synthesize_mmap() code which
is scanning /proc/PID/task/PID/maps and can be time consuming.
Mimic perf top way of handling the option.
If not specified will default to 1 thread, i.e. default behavior before
this option.
On a desktop computer the processing of /proc/PID/task/PID/maps isn't
slow enough to warrant parallel processing and the thread creation has
some cost - hence the default of 1. On a loaded server with
>100 cores it is possible to see synthesis times in the order of
seconds and in this case having the option is desirable.
As the processing is a synchronization point, it is legitimate to worry if
Amdahl's law will apply to this patch. Profiling with this patch in
place:
https://lore.kernel.org/lkml/20200415054050.31645-4-irogers@google.com/
shows:
...
- 32.59% __perf_event__synthesize_threads
- 32.54% __event__synthesize_thread
+ 22.13% perf_event__synthesize_mmap_events
+ 6.68% perf_event__get_comm_ids.constprop.0
+ 1.49% process_synthesized_event
+ 1.29% __GI___readdir64
+ 0.60% __opendir
...
That is the processing is 1.49% of execution time and there is plenty to
make parallel. This is shown in the benchmark in this patch:
Computing performance of multi threaded perf event synthesis by
synthesizing events on CPU 0:
Number of synthesis threads: 1
Average synthesis took: 127729.000 usec (+- 3372.880 usec)
Average num. events: 21548.600 (+- 0.306)
Average time per event 5.927 usec
Number of synthesis threads: 2
Average synthesis took: 88863.500 usec (+- 385.168 usec)
Average num. events: 21552.800 (+- 0.327)
Average time per event 4.123 usec
Number of synthesis threads: 3
Average synthesis took: 83257.400 usec (+- 348.617 usec)
Average num. events: 21553.200 (+- 0.327)
Average time per event 3.863 usec
Number of synthesis threads: 4
Average synthesis took: 75093.000 usec (+- 422.978 usec)
Average num. events: 21554.200 (+- 0.200)
Average time per event 3.484 usec
Number of synthesis threads: 5
Average synthesis took: 64896.600 usec (+- 353.348 usec)
Average num. events: 21558.000 (+- 0.000)
Average time per event 3.010 usec
Number of synthesis threads: 6
Average synthesis took: 59210.200 usec (+- 342.890 usec)
Average num. events: 21560.000 (+- 0.000)
Average time per event 2.746 usec
Number of synthesis threads: 7
Average synthesis took: 54093.900 usec (+- 306.247 usec)
Average num. events: 21562.000 (+- 0.000)
Average time per event 2.509 usec
Number of synthesis threads: 8
Average synthesis took: 48938.700 usec (+- 341.732 usec)
Average num. events: 21564.000 (+- 0.000)
Average time per event 2.269 usec
Where average time per synthesized event goes from 5.927 usec with 1
thread to 2.269 usec with 8. This isn't a linear speed up as not all of
synthesize code has been made parallel. If the synthesis time was about
10 seconds then using 8 threads may bring this down to less than 4.
Signed-off-by: Stephane Eranian <eranian@google.com> Reviewed-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tony Jones <tonyj@suse.de> Cc: yuzhoujian <yuzhoujian@didichuxing.com> Link: http://lore.kernel.org/lkml/20200422155038.9380-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tommi Rantala [Thu, 23 Apr 2020 11:53:40 +0000 (14:53 +0300)]
perf test session topology: Fix data path
Commit 2d4f27999b88 ("perf data: Add global path holder") missed path
conversion in tests/topology.c, causing the "Session topology" testcase
to "hang" (waits forever for input from stdin) when doing "ssh $VM perf
test".
Can be reproduced by running "cat | perf test topo", and crashed by
replacing cat with true:
$ true | perf test -v topo
40: Session topology :
--- start ---
test child forked, pid 3638
templ file: /tmp/perf-test-QPvAch
incompatible file format
incompatible file format (rerun with -v to learn more)
free(): invalid pointer
test child interrupted
---- end ----
Session topology: FAILED!
Committer testing:
Reproduced the above result before the patch and after it is back
working:
# true | perf test -v topo
41: Session topology :
--- start ---
test child forked, pid 19374
templ file: /tmp/perf-test-YOTEQg
CPU 0, core 0, socket 0
CPU 1, core 1, socket 0
CPU 2, core 2, socket 0
CPU 3, core 3, socket 0
CPU 4, core 0, socket 0
CPU 5, core 1, socket 0
CPU 6, core 2, socket 0
CPU 7, core 3, socket 0
test child finished with 0
---- end ----
Session topology: Ok
#
Fixes: 2d4f27999b88 ("perf data: Add global path holder") Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Link: http://lore.kernel.org/lkml/20200423115341.562782-1-tommi.t.rantala@nokia.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The second CPI should not be 1.6 (4,022,591/1,960,061 is 2.1)
root@kbl-ppc:~# perf stat -e cycles,instructions -I1000 --interval-count 2
# time counts unit events
1.000429493 2,869,311 cycles
1.000429493 816,875 instructions # 0.28 insn per cycle
2.001516426 9,260,973 cycles
2.001516426 5,250,634 instructions # 0.87 insn per cycle
The second 'insn per cycle' should not be 0.87 (5,250,634/9,260,973 is
0.57).
The current code uses a global variable 'rt_stat' for tracking and
updating the std dev of runtime stat. Unlike the counts, 'rt_stat' is not
reset for interval. While the counts are reset for interval.
perf_stat_process_counter()
{
if (config->interval)
init_stats(ps->res_stats);
}
So for interval mode, the 'rt_stat' variable should be reset too.
This patch resets 'rt_stat' before read_counters(), so the runtime stat
is only calculated by the counts generated in this interval.
root@kbl-ppc:~# perf stat -e cycles,instructions -I1000 --interval-count 2
# time counts unit events
1.000428555 2,769,714 cycles
1.000428555 774,462 instructions # 0.28 insn per cycle
2.001471562 3,595,904 cycles
2.001471562 1,243,703 instructions # 0.35 insn per cycle
Now the second 'insn per cycle' and CPI are calculated by the counts
generated in this interval.
Signed-off-by: Jin Yao <yao.jin@linux.intel.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Tested-By: Kajol Jain <kjain@linux.ibm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jin Yao <yao.jin@intel.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/20200420145417.6864-1-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jin Yao [Thu, 9 Apr 2020 07:07:55 +0000 (15:07 +0800)]
perf stat: Zero all the 'ena' and 'run' array slot stats for interval mode
As the code comments in perf_stat_process_counter() say, we calculate
counter's data every interval, and the display code shows ps->res_stats
avg value. We need to zero the stats for interval mode.
But the current code only zeros the res_stats[0], it doesn't zero the
res_stats[1] and res_stats[2], which are for ena and run of counter.
This patch zeros the whole res_stats[] for interval mode.
Fixes: 51fd2df1e882 ("perf stat: Fix interval output values") Signed-off-by: Jin Yao <yao.jin@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jin Yao <yao.jin@intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/20200409070755.17261-1-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tommi Rantala [Fri, 17 Apr 2020 13:23:29 +0000 (16:23 +0300)]
perf bench: Fix div-by-zero if runtime is zero
Fix div-by-zero if runtime is zero:
$ perf bench futex hash --runtime=0
# Running 'futex/hash' benchmark:
Run summary [PID 12090]: 4 threads, each operating on 1024 [private] futexes for 0 secs.
Floating point exception (core dumped)
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200417132330.119407-4-tommi.t.rantala@nokia.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tommi Rantala [Fri, 17 Apr 2020 13:23:26 +0000 (16:23 +0300)]
perf cgroup: Avoid needless closing of unopened fd
Do not bother with close() if fd is not valid, just to silence valgrind:
$ valgrind ./perf script
==59169== Memcheck, a memory error detector
==59169== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==59169== Using Valgrind-3.14.0 and LibVEX; rerun with -h for copyright info
==59169== Command: ./perf script
==59169==
==59169== Warning: invalid file descriptor -1 in syscall close()
==59169== Warning: invalid file descriptor -1 in syscall close()
==59169== Warning: invalid file descriptor -1 in syscall close()
==59169== Warning: invalid file descriptor -1 in syscall close()
==59169== Warning: invalid file descriptor -1 in syscall close()
==59169== Warning: invalid file descriptor -1 in syscall close()
==59169== Warning: invalid file descriptor -1 in syscall close()
==59169== Warning: invalid file descriptor -1 in syscall close()
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/20200417132330.119407-1-tommi.t.rantala@nokia.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
tools/vm: fix cross-compile build
coredump: fix null pointer dereference on coredump
mm: shmem: disable interrupt when acquiring info->lock in userfaultfd_copy path
shmem: fix possible deadlocks on shmlock_user_lock
vmalloc: fix remap_vmalloc_range() bounds checks
mm/shmem: fix build without THP
mm/ksm: fix NULL pointer dereference when KSM zero page is enabled
tools/build: tweak unused value workaround
checkpatch: fix a typo in the regex for $allocFunctions
mm, gup: return EINTR when gup is interrupted by fatal signals
mm/hugetlb: fix a addressing exception caused by huge_pte_offset
MAINTAINERS: add an entry for kfifo
mm/userfaultfd: disable userfaultfd-wp on x86_32
slub: avoid redzone when choosing freepointer location
sh: fix build error in mm/init.c
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"Bugfixes, and a few cleanups to the newly-introduced assembly language
vmentry code for AMD"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: PPC: Book3S HV: Handle non-present PTEs in page fault functions
kvm: Disable objtool frame pointer checking for vmenter.S
MAINTAINERS: add a reviewer for KVM/s390
KVM: s390: Fix PV check in deliverable_irqs()
kvm: Handle reads of SandyBridge RAPL PMU MSRs rather than injecting #GP
KVM: Remove CREATE_IRQCHIP/SET_PIT2 race
KVM: SVM: Fix __svm_vcpu_run declaration.
KVM: SVM: Do not setup frame pointer in __svm_vcpu_run
KVM: SVM: Fix build error due to missing release_pages() include
KVM: SVM: Do not mark svm_vcpu_run with STACK_FRAME_NON_STANDARD
kvm: nVMX: match comment with return type for nested_vmx_exit_reflected
kvm: nVMX: reflect MTF VM-exits if injected by L1
KVM: s390: Return last valid slot if approx index is out-of-bounds
KVM: Check validity of resolved slot when searching memslots
KVM: VMX: Enable machine check support for 32bit targets
KVM: SVM: move more vmentry code to assembly
KVM: SVM: fix compilation with modular PSP and non-modular KVM
Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio fixes and cleanups from Michael Tsirkin:
- Some bug fixes
- Cleanup a couple of issues that surfaced meanwhile
- Disable vhost on ARM with OABI for now - to be fixed fully later in
the cycle or in the next release.
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (24 commits)
vhost: disable for OABI
virtio: drop vringh.h dependency
virtio_blk: add a missing include
virtio-balloon: Avoid using the word 'report' when referring to free page hinting
virtio-balloon: make virtballoon_free_page_report() static
vdpa: fix comment of vdpa_register_device()
vdpa: make vhost, virtio depend on menu
vdpa: allow a 32 bit vq alignment
drm/virtio: fix up for include file changes
remoteproc: pull in slab.h
rpmsg: pull in slab.h
virtio_input: pull in slab.h
remoteproc: pull in slab.h
virtio-rng: pull in slab.h
virtgpu: pull in uaccess.h
tools/virtio: make asm/barrier.h self contained
tools/virtio: define aligned attribute
virtio/test: fix up after IOTLB changes
vhost: Create accessors for virtqueues private_data
vdpasim: Return status in vdpasim_get_status
...
Merge tag 'tpmdd-next-20200421' of git://git.infradead.org/users/jjs/linux-tpmdd
Pull tpm fixes from Jarkko Sakkinen:
"A few bug fixes"
* tag 'tpmdd-next-20200421' of git://git.infradead.org/users/jjs/linux-tpmdd:
tpm/tpm_tis: Free IRQ if probing fails
tpm: fix wrong return value in tpm_pcr_extend
tpm: ibmvtpm: retry on H_CLOSED in tpm_ibmvtpm_send()
tpm: Export tpm2_get_cc_attrs_tbl for ibmvtpm driver as module
Merge tag 'clang-format-for-linus-v5.7-rc3' of git://github.com/ojeda/linux
Pull clang-format fixlets from Miguel Ojeda:
"Two trivial clang-format changes:
- Don't indent C++ namespaces (Ian Rogers)
- The usual clang-format macro list update (Miguel Ojeda)"
* tag 'clang-format-for-linus-v5.7-rc3' of git://github.com/ojeda/linux:
clang-format: Update with the latest for_each macro list
clang-format: don't indent namespaces
Lucas Stach [Tue, 21 Apr 2020 01:14:23 +0000 (18:14 -0700)]
tools/vm: fix cross-compile build
Commit 7ed1c1901fe5 ("tools: fix cross-compile var clobbering") moved
the setup of the CC variable to tools/scripts/Makefile.include to make
the behavior consistent across all the tools Makefiles.
As the vm tools missed the include we end up with the wrong CC in a
cross-compiling evironment.
Fixes: 7ed1c1901fe5 (tools: fix cross-compile var clobbering) Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Martin Kelly <martin@martingkelly.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200416104748.25243-1-l.stach@pengutronix.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yang Shi [Tue, 21 Apr 2020 01:14:17 +0000 (18:14 -0700)]
mm: shmem: disable interrupt when acquiring info->lock in userfaultfd_copy path
Syzbot reported the below lockdep splat:
WARNING: possible irq lock inversion dependency detected
5.6.0-rc7-syzkaller #0 Not tainted
--------------------------------------------------------
syz-executor.0/10317 just changed the state of lock: ffff888021d16568 (&(&info->lock)->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:338 [inline] ffff888021d16568 (&(&info->lock)->rlock){+.+.}, at: shmem_mfill_atomic_pte+0x1012/0x21c0 mm/shmem.c:2407
but this lock was taken by another, SOFTIRQ-safe lock in the past:
(&(&xa->xa_lock)->rlock#5){..-.}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
It is because CPU 0 held info->lock with IRQ enabled in userfaultfd_copy
path, then CPU 1 is splitting a THP which held xa_lock and info->lock in
IRQ disabled context at the same time. If softirq comes in to acquire
xa_lock, the deadlock would be triggered.
The fix is to acquire/release info->lock with *_irq version instead of
plain spin_{lock,unlock} to make it softirq safe.
Fixes: 4c27fe4c4c84 ("userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd support") Reported-by: syzbot+e27980339d305f2dbfd9@syzkaller.appspotmail.com Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: syzbot+e27980339d305f2dbfd9@syzkaller.appspotmail.com Acked-by: Hugh Dickins <hughd@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Link: http://lkml.kernel.org/r/1587061357-122619-1-git-send-email-yang.shi@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
shmem: fix possible deadlocks on shmlock_user_lock
Recent commit 71725ed10c40 ("mm: huge tmpfs: try to split_huge_page()
when punching hole") has allowed syzkaller to probe deeper, uncovering a
long-standing lockdep issue between the irq-unsafe shmlock_user_lock,
the irq-safe xa_lock on mapping->i_pages, and shmem inode's info->lock
which nests inside xa_lock (or tree_lock) since 4.8's shmem_uncharge().
user_shm_lock(), servicing SysV shmctl(SHM_LOCK), wants
shmlock_user_lock while its caller shmem_lock() holds info->lock with
interrupts disabled; but hugetlbfs_file_setup() calls user_shm_lock()
with interrupts enabled, and might be interrupted by a writeback endio
wanting xa_lock on i_pages.
This may not risk an actual deadlock, since shmem inodes do not take
part in writeback accounting, but there are several easy ways to avoid
it.
Requiring interrupts disabled for shmlock_user_lock would be easy, but
it's a high-level global lock for which that seems inappropriate.
Instead, recall that the use of info->lock to guard info->flags in
shmem_lock() dates from pre-3.1 days, when races with SHMEM_PAGEIN and
SHMEM_TRUNCATE could occur: nowadays it serves no purpose, the only flag
added or removed is VM_LOCKED itself, and calls to shmem_lock() an inode
are already serialized by the caller.
Take info->lock out of the chain and the possibility of deadlock or
lockdep warning goes away.
remap_vmalloc_range() has had various issues with the bounds checks it
promises to perform ("This function checks that addr is a valid
vmalloc'ed area, and that it is big enough to cover the vma") over time,
e.g.:
- not detecting pgoff<<PAGE_SHIFT overflow
- not detecting (pgoff<<PAGE_SHIFT)+usize overflow
- not checking whether addr and addr+(pgoff<<PAGE_SHIFT) are the same
vmalloc allocation
- comparing a potentially wildly out-of-bounds pointer with the end of
the vmalloc region
In particular, since commit fc9702273e2e ("bpf: Add mmap() support for
BPF_MAP_TYPE_ARRAY"), unprivileged users can cause kernel null pointer
dereferences by calling mmap() on a BPF map with a size that is bigger
than the distance from the start of the BPF map to the end of the
address space.
This could theoretically be used as a kernel ASLR bypass, by using
whether mmap() with a given offset oopses or returns an error code to
perform a binary search over the possible address range.
To allow remap_vmalloc_range_partial() to verify that addr and
addr+(pgoff<<PAGE_SHIFT) are in the same vmalloc region, pass the offset
to remap_vmalloc_range_partial() instead of adding it to the pointer in
remap_vmalloc_range().
In remap_vmalloc_range_partial(), fix the check against
get_vm_area_size() by using size comparisons instead of pointer
comparisons, and add checks for pgoff.
Fixes: 833423143c3a ("[PATCH] mm: introduce remap_vmalloc_range()") Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: stable@vger.kernel.org Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Song Liu <songliubraving@fb.com> Cc: Yonghong Song <yhs@fb.com> Cc: Andrii Nakryiko <andriin@fb.com> Cc: John Fastabend <john.fastabend@gmail.com> Cc: KP Singh <kpsingh@chromium.org> Link: http://lkml.kernel.org/r/20200415222312.236431-1-jannh@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Muchun Song [Tue, 21 Apr 2020 01:14:04 +0000 (18:14 -0700)]
mm/ksm: fix NULL pointer dereference when KSM zero page is enabled
find_mergeable_vma() can return NULL. In this case, it leads to a crash
when we access vm_mm(its offset is 0x40) later in write_protect_page.
And this case did happen on our server. The following call trace is
captured in kernel 4.19 with the following patch applied and KSM zero
page enabled on our server.
commit e86c59b1b12d ("mm/ksm: improve deduplication of zero pages with colouring")
[songmuchun@bytedance.com: if the vma is out of date, just exit] Link: http://lkml.kernel.org/r/20200416025034.29780-1-songmuchun@bytedance.com
[akpm@linux-foundation.org: add the conventional braces, replace /** with /*] Fixes: e86c59b1b12d ("mm/ksm: improve deduplication of zero pages with colouring") Co-developed-by: Xiongchun Duan <duanxiongchun@bytedance.com> Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Hugh Dickins <hughd@google.com> Cc: Yang Shi <yang.shi@linux.alibaba.com> Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com> Cc: Markus Elfring <Markus.Elfring@web.de> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200416025034.29780-1-songmuchun@bytedance.com Link: http://lkml.kernel.org/r/20200414132905.83819-1-songmuchun@bytedance.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Clang has -Wself-assign enabled by default under -Wall, which always
gets -Werror'ed on this file, causing sync-compare-and-swap to be
disabled by default.
The generally-accepted way to spell "this value is intentionally
unused," is casting it to `void`. This is accepted by both GCC and
Clang with -Wall enabled: https://godbolt.org/z/qqZ9r3
Signed-off-by: George Burgess IV <gbiv@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Link: http://lkml.kernel.org/r/20200414195638.156123-1-gbiv@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Tue, 21 Apr 2020 01:13:55 +0000 (18:13 -0700)]
mm, gup: return EINTR when gup is interrupted by fatal signals
EINTR is the usual error code which other killable interfaces return.
This is the case for the other fatal_signal_pending break out from the
same function. Make the code consistent.
ERESTARTSYS is also quite confusing because the signal is fatal and so
no restart will happen before returning to the userspace.
Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Xu <peterx@redhat.com> Cc: Hillf Danton <hdanton@sina.com> Link: http://lkml.kernel.org/r/20200409071133.31734-1-mhocko@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For 1G hugepages, huge_pte_offset() wants to return NULL or pudp, but it
may return a wrong 'pmdp' if there is a race. Please look at the
following code snippet:
...
pud = pud_offset(p4d, addr);
if (sz != PUD_SIZE && pud_none(*pud))
return NULL;
/* hugepage or swap? */
if (pud_huge(*pud) || !pud_present(*pud))
return (pte_t *)pud;
pmd = pmd_offset(pud, addr);
if (sz != PMD_SIZE && pmd_none(*pmd))
return NULL;
/* hugepage or swap? */
if (pmd_huge(*pmd) || !pmd_present(*pmd))
return (pte_t *)pmd;
...
The following sequence would trigger this bug:
- CPU0: sz = PUD_SIZE and *pud = 0 , continue
- CPU0: "pud_huge(*pud)" is false
- CPU1: calling hugetlb_no_page and set *pud to xxxx8e7(PRESENT)
- CPU0: "!pud_present(*pud)" is false, continue
- CPU0: pmd = pmd_offset(pud, addr) and maybe return a wrong pmdp
However, we want CPU0 to return NULL or pudp in this case.
We must make sure there is exactly one dereference of pud and pmd.
Signed-off-by: Longpeng <longpeng2@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200413010342.771-1-longpeng2@huawei.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kfifo has been written by Stefani Seibold and she's implicitly expected
to Ack any changes to it. She's not however officially listed as kfifo
maintainer which leads to delays in patch review. This patch proposes
to add an explitic entry for kfifo to MAINTAINERS file.
[akpm@linux-foundation.org: alphasort F: entries, per Joe]
[akpm@linux-foundation.org: remove colon, per Bartosz] Link: http://lkml.kernel.org/r/20200124174533.21815-1-brgl@bgdev.pl Link: http://lkml.kernel.org/r/20200413104250.26683-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Acked-by: Stefani Seibold <stefani@seibold.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
slub: avoid redzone when choosing freepointer location
Marco Elver reported system crashes when booting with "slub_debug=Z".
The freepointer location (s->offset) was not taking into account that
the "inuse" size that includes the redzone area should not be used by
the freelist pointer. Change the calculation to save the area of the
object that an inline freepointer may be written into.
Fixes: 3202fa62fb43 ("slub: relocate freelist pointer to middle of object") Reported-by: Marco Elver <elver@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Marco Elver <elver@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Link: http://lkml.kernel.org/r/202004151054.BD695840@keescook Link: https://lore.kernel.org/linux-mm/20200415164726.GA234932@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since cd758a9b57ee "KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot in HPT
page fault handler", it's been possible in fairly rare circumstances to
load a non-present PTE in kvmppc_book3s_hv_page_fault() when running a
guest on a POWER8 host.
Because that case wasn't checked for, we could misinterpret the non-present
PTE as being a cache-inhibited PTE. That could mismatch with the
corresponding hash PTE, which would cause the function to fail with -EFAULT
a little further down. That would propagate up to the KVM_RUN ioctl()
generally causing the KVM userspace (usually qemu) to fall over.
This addresses the problem by catching that case and returning to the guest
instead.
For completeness, this fixes the radix page fault handler in the same
way. For radix this didn't cause any obvious misbehaviour, because we
ended up putting the non-present PTE into the guest's partition-scoped
page tables, leading immediately to another hypervisor data/instruction
storage interrupt, which would go through the page fault path again
and fix things up.
Fixes: cd758a9b57ee "KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot in HPT page fault handler"
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1820402 Reported-by: David Gibson <david@gibson.dropbear.id.au> Tested-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Jarkko Sakkinen [Sun, 12 Apr 2020 17:04:12 +0000 (20:04 +0300)]
tpm/tpm_tis: Free IRQ if probing fails
Call disable_interrupts() if we have to revert to polling in order not to
unnecessarily reserve the IRQ for the life-cycle of the driver.
Cc: stable@vger.kernel.org # 4.5.x Reported-by: Hans de Goede <hdegoede@redhat.com> Fixes: e3837e74a06d ("tpm_tis: Refactor the interrupt setup") Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
For the algorithm that does not match the bank, a positive
value EINVAL is returned here. I think this is a typo error.
It is necessary to return an error value.
Cc: stable@vger.kernel.org # 5.4.x Fixes: 9f75c8224631 ("KEYS: trusted: correctly initialize digests and fix locking issue") Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com> Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
George Wilson [Fri, 20 Mar 2020 03:27:58 +0000 (23:27 -0400)]
tpm: ibmvtpm: retry on H_CLOSED in tpm_ibmvtpm_send()
tpm_ibmvtpm_send() can fail during PowerVM Live Partition Mobility resume
with an H_CLOSED return from ibmvtpm_send_crq(). The PAPR says, 'The
"partner partition suspended" transport event disables the associated CRQ
such that any H_SEND_CRQ hcall() to the associated CRQ returns H_Closed
until the CRQ has been explicitly enabled using the H_ENABLE_CRQ hcall.'
This patch adds a check in tpm_ibmvtpm_send() for an H_CLOSED return from
ibmvtpm_send_crq() and in that case calls tpm_ibmvtpm_resume() and
retries the ibmvtpm_send_crq() once.
Cc: stable@vger.kernel.org # 3.7.x Fixes: 132f76294744 ("drivers/char/tpm: Add new device driver to support IBM vTPM") Reported-by: Linh Pham <phaml@us.ibm.com> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: George Wilson <gcwilson@linux.ibm.com> Tested-by: Linh Pham <phaml@us.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Fixes: 18b3670d79ae ("tpm: ibmvtpm: Add support for TPM2") Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
vhost is currently broken on the some ARM configs.
The reason is that the ring element addresses are passed between
components with different alignments assumptions. Thus, if
guest selects a pointer and host then gets and dereferences
it, then alignment assumed by the host's compiler might be
greater than the actual alignment of the pointer.
compiler on the host from assuming pointer is aligned.
This actually triggers on ARM with -mabi=apcs-gnu - which is a
deprecated configuration. With this OABI, compiler assumes that
all structures are 4 byte aligned - which is stronger than
virtio guarantees for available and used rings, which are
merely 2 bytes. Thus a guest without -mabi=apcs-gnu running
on top of host with -mabi=apcs-gnu will be broken.
The correct fix is to force alignment of structures - however
that is an intrusive fix that's best deferred until the next release.
We didn't previously support such ancient systems at all - this surfaced
after vdpa support prompted removing dependency of vhost on
VIRTULIZATION. So for now, let's just add something along the lines of
depends on !ARM || AEABI
to the virtio Kconfig declaration, and add a comment that it has to do
with struct member alignment.
Note: we can't make VHOST and VHOST_RING themselves have
a dependency since these are selected. Add a new symbol for that.
We should be able to drop this dependency down the road.
Fixes: 20c384f1ea1a0bc7 ("vhost: refine vhost and vringh kconfig") Suggested-by: Ard Biesheuvel <ardb@kernel.org> Suggested-by: Richard Earnshaw <Richard.Earnshaw@arm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Eric Farman [Wed, 15 Apr 2020 19:03:53 +0000 (21:03 +0200)]
KVM: s390: Fix PV check in deliverable_irqs()
The diag 0x44 handler, which handles a directed yield, goes into a
a codepath that does a kvm_for_each_vcpu() and ultimately
deliverable_irqs(). The new check for kvm_s390_pv_cpu_is_protected()
contains an assertion that the vcpu->mutex is held, which isn't going
to be the case in this scenario.
The result is a plethora of these messages if the lock debugging
is enabled, and thus an implication that we have a problem.
WARNING: CPU: 9 PID: 16167 at arch/s390/kvm/kvm-s390.h:239 deliverable_irqs+0x1c6/0x1d0 [kvm]
...snip...
Call Trace:
[<000003ff80429bf2>] deliverable_irqs+0x1ca/0x1d0 [kvm]
([<000003ff80429b34>] deliverable_irqs+0x10c/0x1d0 [kvm])
[<000003ff8042ba82>] kvm_s390_vcpu_has_irq+0x2a/0xa8 [kvm]
[<000003ff804101e2>] kvm_arch_dy_runnable+0x22/0x38 [kvm]
[<000003ff80410284>] kvm_vcpu_on_spin+0x8c/0x1d0 [kvm]
[<000003ff80436888>] kvm_s390_handle_diag+0x3b0/0x768 [kvm]
[<000003ff80425af4>] kvm_handle_sie_intercept+0x1cc/0xcd0 [kvm]
[<000003ff80422bb0>] __vcpu_run+0x7b8/0xfd0 [kvm]
[<000003ff80423de6>] kvm_arch_vcpu_ioctl_run+0xee/0x3e0 [kvm]
[<000003ff8040ccd8>] kvm_vcpu_ioctl+0x2c8/0x8d0 [kvm]
[<00000001504ced06>] ksys_ioctl+0xae/0xe8
[<00000001504cedaa>] __s390x_sys_ioctl+0x2a/0x38
[<0000000150cb9034>] system_call+0xd8/0x2d8
2 locks held by CPU 2/KVM/16167:
#0: 00000001951980c0 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x90/0x8d0 [kvm]
#1: 000000019599c0f0 (&kvm->srcu){....}, at: __vcpu_run+0x4bc/0xfd0 [kvm]
Last Breaking-Event-Address:
[<000003ff80429b34>] deliverable_irqs+0x10c/0x1d0 [kvm]
irq event stamp: 11967
hardirqs last enabled at (11975): [<00000001502992f2>] console_unlock+0x4ca/0x650
hardirqs last disabled at (11982): [<0000000150298ee8>] console_unlock+0xc0/0x650
softirqs last enabled at (7940): [<0000000150cba6ca>] __do_softirq+0x422/0x4d8
softirqs last disabled at (7929): [<00000001501cd688>] do_softirq_own_stack+0x70/0x80
Considering what's being done here, let's fix this by removing the
mutex assertion rather than acquiring the mutex for every other vcpu.
Fixes: 201ae986ead7 ("KVM: s390: protvirt: Implement interrupt injection") Signed-off-by: Eric Farman <farman@linux.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Link: https://lore.kernel.org/r/20200415190353.63625-1-farman@linux.ibm.com Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Brian Geffon [Fri, 17 Apr 2020 17:25:56 +0000 (10:25 -0700)]
mm: Fix MREMAP_DONTUNMAP accounting on VMA merge
When remapping a mapping where a portion of a VMA is remapped
into another portion of the VMA it can cause the VMA to become
split. During the copy_vma operation the VMA can actually
be remerged if it's an anonymous VMA whose pages have not yet
been faulted. This isn't normally a problem because at the end
of the remap the original portion is unmapped causing it to
become split again.
However, MREMAP_DONTUNMAP leaves that original portion in place which
means that the VMA which was split and then remerged is not actually
split at the end of the mremap. This patch fixes a bug where
we don't detect that the VMAs got remerged and we end up
putting back VM_ACCOUNT on the next mapping which is completely
unreleated. When that next mapping is unmapped it results in
incorrectly unaccounting for the memory which was never accounted,
and eventually we will underflow on the memory comittment.
There is also another issue which is similar, we're currently
accouting for the number of pages in the new_vma but that's wrong.
We need to account for the length of the remap operation as that's
all that is being added. If there was a mapping already at that
location its comittment would have been adjusted as part of
the munmap at the start of the mremap.
Merge tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
Pull clk fixes from Stephen Boyd:
"Two build fixes for a couple clk drivers and a fix for the Unisoc
serial clk where we want to keep it on for earlycon"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: sprd: don't gate uart console clock
clk: mmp2: fix link error without mmp2
clk: asm9260: fix __clk_hw_register_fixed_rate_with_accuracy typo
Merge tag 'x86-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 and objtool fixes from Thomas Gleixner:
"A set of fixes for x86 and objtool:
objtool:
- Ignore the double UD2 which is emitted in BUG() when
CONFIG_UBSAN_TRAP is enabled.
- Support clang non-section symbols in objtool ORC dump
- Fix switch table detection in .text.unlikely
- Make the BP scratch register warning more robust.
x86:
- Increase microcode maximum patch size for AMD to cope with new CPUs
which have a larger patch size.
- Fix a crash in the resource control filesystem when the removal of
the default resource group is attempted.
- Preserve Code and Data Prioritization enabled state accross CPU
hotplug.
- Update split lock cpu matching to use the new X86_MATCH macros.
- Change the split lock enumeration as Intel finaly decided that the
IA32_CORE_CAPABILITIES bits are not architectural contrary to what
the SDM claims. !@#%$^!
- Add Tremont CPU models to the split lock detection cpu match.
- Add a missing static attribute to make sparse happy"
* tag 'x86-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/split_lock: Add Tremont family CPU models
x86/split_lock: Bits in IA32_CORE_CAPABILITIES are not architectural
x86/resctrl: Preserve CDP enable over CPU hotplug
x86/resctrl: Fix invalid attempt at removing the default resource group
x86/split_lock: Update to use X86_MATCH_INTEL_FAM6_MODEL()
x86/umip: Make umip_insns static
x86/microcode/AMD: Increase microcode PATCH_MAX_SIZE
objtool: Make BP scratch register warning more robust
objtool: Fix switch table detection in .text.unlikely
objtool: Support Clang non-section symbols in ORC generation
objtool: Support Clang non-section symbols in ORC dump
objtool: Fix CONFIG_UBSAN_TRAP unreachable warnings
Merge tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull time namespace fix from Thomas Gleixner:
"An update for the proc interface of time namespaces: Use symbolic
names instead of clockid numbers. The usability nuisance of numbers
was noticed by Michael when polishing the man page"
* tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets
Merge tag 'perf-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf tooling fixes and updates from Thomas Gleixner:
- Fix the header line of perf stat output for '--metric-only --per-socket'
- Fix the python build with clang
- The usual tools UAPI header synchronization
* tag 'perf-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tools headers: Synchronize linux/bits.h with the kernel sources
tools headers: Adopt verbatim copy of compiletime_assert() from kernel sources
tools headers: Update x86's syscall_64.tbl with the kernel sources
tools headers UAPI: Sync drm/i915_drm.h with the kernel sources
tools headers UAPI: Update tools's copy of drm.h headers
tools headers kvm: Sync linux/kvm.h with the kernel sources
tools headers UAPI: Sync linux/fscrypt.h with the kernel sources
tools include UAPI: Sync linux/vhost.h with the kernel sources
tools arch x86: Sync asm/cpufeatures.h with the kernel sources
tools headers UAPI: Sync linux/mman.h with the kernel
tools headers UAPI: Sync sched.h with the kernel
tools headers: Update linux/vdso.h and grab a copy of vdso/const.h
perf stat: Fix no metric header if --per-socket and --metric-only set
perf python: Check if clang supports -fno-semantic-interposition
tools arch x86: Sync the msr-index.h copy with the kernel sources
Merge tag 'irq-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
"A set of fixes/updates for the interrupt subsystem:
- Remove setup_irq() and remove_irq(). All users have been converted
so remove them before new users surface.
- A set of bugfixes for various interrupt chip drivers
- Add a few missing static attributes to address sparse warnings"
* tag 'irq-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/irq-bcm7038-l1: Make bcm7038_l1_of_init() static
irqchip/irq-mvebu-icu: Make legacy_bindings static
irqchip/meson-gpio: Fix HARDIRQ-safe -> HARDIRQ-unsafe lock order
irqchip/sifive-plic: Fix maximum priority threshold value
irqchip/ti-sci-inta: Fix processing of masked irqs
irqchip/mbigen: Free msi_desc on device teardown
irqchip/gic-v4.1: Update effective affinity of virtual SGIs
irqchip/gic-v4.1: Add support for VPENDBASER's Dirty+Valid signaling
genirq: Remove setup_irq() and remove_irq()
Merge tag 'sched-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Thomas Gleixner:
"Two fixes for the scheduler:
- Work around an uninitialized variable warning where GCC can't
figure it out.
- Allow 'isolcpus=' to skip unknown subparameters so that older
kernels work with the commandline of a newer kernel. Improve the
error output while at it"
* tag 'sched-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/vtime: Work around an unitialized variable warning
sched/isolation: Allow "isolcpus=" to skip unknown sub-parameters
Merge tag 'core-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU fix from Thomas Gleixner:
"A single bugfix for RCU to prevent taking a lock in NMI context"
* tag 'core-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rcu: Don't acquire lock in NMI handler in rcu_nmi_enter_common()
Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"Miscellaneous bug fixes and cleanups for ext4, including a fix for
generic/388 in data=journal mode, removing some BUG_ON's, and cleaning
up some compiler warnings"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: convert BUG_ON's to WARN_ON's in mballoc.c
ext4: increase wait time needed before reuse of deleted inode numbers
ext4: remove set but not used variable 'es' in ext4_jbd2.c
ext4: remove set but not used variable 'es'
ext4: do not zeroout extents beyond i_disksize
ext4: fix return-value types in several function comments
ext4: use non-movable memory for superblock readahead
ext4: use matching invalidatepage in ext4_writepage
Merge tag '5.7-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Three small smb3 fixes: two debug related (helping network tracing for
SMB2 mounts, and the other removing an unintended debug line on
signing failures), and one fixing a performance problem with 64K
pages"
* tag '5.7-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb3: remove overly noisy debug line in signing errors
cifs: improve read performance for page size 64KB & cache=strict & vers=2.1+
cifs: dump the session id and keys also for SMB2 sessions
Merge tag 'flexible-array-member-5.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux
Pull flexible-array member conversion from Gustavo Silva:
"The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array
member[1][2], introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof
operator may not be applied. As a quirk of the original
implementation of zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible
array members have incomplete type[1]. There are some instances of
code in which the sizeof operator is being incorrectly/erroneously
applied to zero-length arrays and the result is zero. Such instances
may be hiding some bugs. So, this work (flexible-array member
convertions) will also help to get completely rid of those sorts of
issues.
Notice that all of these patches have been baking in linux-next for
quite a while now and, 238 more of these patches have already been
merged into 5.7-rc1.
There are a couple hundred more of these issues waiting to be
addressed in the whole codebase"
* tag 'flexible-array-member-5.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (28 commits)
xattr.h: Replace zero-length array with flexible-array member
uapi: linux: fiemap.h: Replace zero-length array with flexible-array member
uapi: linux: dlm_device.h: Replace zero-length array with flexible-array member
tpm_eventlog.h: Replace zero-length array with flexible-array member
ti_wilink_st.h: Replace zero-length array with flexible-array member
swap.h: Replace zero-length array with flexible-array member
skbuff.h: Replace zero-length array with flexible-array member
sched: topology.h: Replace zero-length array with flexible-array member
rslib.h: Replace zero-length array with flexible-array member
rio.h: Replace zero-length array with flexible-array member
posix_acl.h: Replace zero-length array with flexible-array member
platform_data: wilco-ec.h: Replace zero-length array with flexible-array member
memcontrol.h: Replace zero-length array with flexible-array member
list_lru.h: Replace zero-length array with flexible-array member
lib: cpu_rmap: Replace zero-length array with flexible-array member
irq.h: Replace zero-length array with flexible-array member
ihex.h: Replace zero-length array with flexible-array member
igmp.h: Replace zero-length array with flexible-array member
genalloc.h: Replace zero-length array with flexible-array member
ethtool.h: Replace zero-length array with flexible-array member
...
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Seven fixes: three in target, one on a sg error leg, two in qla2xxx
fixing warnings introduced in the last merge window and updating
MAINTAINERS and one in hisi_sas fixing a problem introduced by libata"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: sg: add sg_remove_request in sg_common_write
scsi: target: tcmu: reset_ring should reset TCMU_DEV_BIT_BROKEN
scsi: target: fix PR IN / READ FULL STATUS for FC
scsi: target: Write NULL to *port_nexus_ptr if no ISID
scsi: MAINTAINERS: Update qla2xxx FC-SCSI driver maintainer
scsi: qla2xxx: Fix regression warnings
scsi: hisi_sas: Fix build error without SATA_HOST
xattr.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
uapi: linux: fiemap.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
uapi: linux: dlm_device.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
tpm_eventlog.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
ti_wilink_st.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
swap.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
skbuff.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sched: topology.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
rslib.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
rio.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
posix_acl.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
platform_data: wilco-ec.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
memcontrol.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
list_lru.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
lib: cpu_rmap: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
irq.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
ihex.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
igmp.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
genalloc.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
ethtool.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
energy_model.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
enclosure.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
dirent.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
digsig.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
can: dev: peak_canfd.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
projects / kernel.git / log