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Linux kernel
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Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix TUI exit screen refresh race condition in 'perf top'.
- Fix parsing of Intel PT VM time correlation arguments.
- Honour CPU filtering command line request of a script's switch events
in 'perf script'.
- Fix printing of switch events in Intel PT python script.
- Fix duplicate alias events list printing in 'perf list', noticed on
heterogeneous arm64 systems.
- Fix return value of ids__new(), users expect NULL for failure, not
ERR_PTR(-ENOMEM).
* tag 'perf-tools-fixes-for-v5.16-2022-01-02' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf top: Fix TUI exit screen refresh race condition
perf pmu: Fix alias events list
perf scripts python: intel-pt-events.py: Fix printing of switch events
perf script: Fix CPU filtering of a script's switch events
perf intel-pt: Fix parsing of VM time correlation arguments
perf expr: Fix return value of ids__new()
Pull i2c fixes from Wolfram Sang:
"Better input validation for compat ioctls and a documentation bugfix
for 5.16"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
Docs: Fixes link to I2C specification
i2c: validate user data in compat ioctl
When the following command is executed several times, a coredump file is
generated.
$ timeout -k 9 5 perf top -e task-clock
*******
*******
*******
0.01% [kernel] [k] __do_softirq
0.01% libpthread-2.28.so [.] __pthread_mutex_lock
0.01% [kernel] [k] __ll_sc_atomic64_sub_return
double free or corruption (!prev) perf top --sort comm,dso
timeout: the monitored command dumped core
When we terminate "perf top" using sending signal method,
SLsmg_reset_smg() called. SLsmg_reset_smg() resets the SLsmg screen
management routines by freeing all memory allocated while it was active.
However SLsmg_reinit_smg() maybe be called by another thread.
SLsmg_reinit_smg() will free the same memory accessed by
SLsmg_reset_smg(), thus it results in a double free.
SLsmg_reinit_smg() is called already protected by ui__lock, so we fix
the problem by adding pthread_mutex_trylock of ui__lock when calling
SLsmg_reset_smg().
Signed-off-by: Wenyu Liu <liuwenyu7@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.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>
Cc: wuxu.wu@huawei.com
Link: http://lore.kernel.org/lkml/a91e3943-7ddc-f5c0-a7f5-360f073c20e6@huawei.com
Signed-off-by: Hewenliang <hewenliang4@huawei.com>
Signed-off-by: yaowenbin <yaowenbin1@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull x86 fix from Borislav Petkov:
- Use the proper CONFIG symbol in a preprocessor check.
* tag 'x86_urgent_for_v5.16_rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/build: Use the proper name CONFIG_FW_LOADER
The link to the I2C specification is broken. Although
"https://www.nxp.com" hosts Rev 7 (2021) of this specification, it is
behind a login-wall. Thus, an additional link has been added (which
doesn't require a login) and the NXP official docs link has been
updated.
Signed-off-by: Deep Majumder <deep@fastmail.in>
[wsa: minor updates to text and commit message]
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Commit 0e0ae8742207c3b4 ("perf list: Display hybrid PMU events with cpu
type") changes the event list for uncore PMUs or arm64 heterogeneous CPU
systems, such that duplicate aliases are incorrectly listed per PMU
(which they should not be), like:
# perf list
...
unc_cbo_cache_lookup.any_es
[Unit: uncore_cbox L3 Lookup any request that access cache and found
line in E or S-state]
unc_cbo_cache_lookup.any_es
[Unit: uncore_cbox L3 Lookup any request that access cache and found
line in E or S-state]
unc_cbo_cache_lookup.any_i
[Unit: uncore_cbox L3 Lookup any request that access cache and found
line in I-state]
unc_cbo_cache_lookup.any_i
[Unit: uncore_cbox L3 Lookup any request that access cache and found
line in I-state]
...
Notice how the events are listed twice.
The named commit changed how we remove duplicate events, in that events
for different PMUs are not treated as duplicates. I suppose this is to
handle how "Each hybrid pmu event has been assigned with a pmu name".
Fix PMU alias listing by restoring behaviour to remove duplicates for
non-hybrid PMUs.
Fixes: 0e0ae8742207c3b4 ("perf list: Display hybrid PMU events with cpu type")
Signed-off-by: John Garry <john.garry@huawei.com>
Tested-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.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>
Link: https://lore.kernel.org/r/1640103090-140490-1-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull input fixes from Dmitry Torokhov:
"Two small fixups for spaceball joystick driver and appletouch touchpad
driver"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: spaceball - fix parsing of movement data packets
Input: appletouch - initialize work before device registration
Commit in Fixes intends to add the expression regex only when FW_LOADER
is enabled - not FW_LOADER_BUILTIN. Latter is a leftover from a previous
patchset and not a valid config item.
So, adjust the condition to the actual name of the config.
[ bp: Cleanup commit message. ]
Fixes: c8dcf655ec81 ("x86/build: Tuck away built-in firmware under FW_LOADER")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20211229111553.5846-1-lukas.bulwahn@gmail.com
Wrong user data may cause warning in i2c_transfer(), ex: zero msgs.
Userspace should not be able to trigger warnings, so this patch adds
validation checks for user data in compact ioctl to prevent reported
warnings
Reported-and-tested-by: syzbot+e417648b303855b91d8a@syzkaller.appspotmail.com
Fixes: 7d5cb45655f2 ("i2c compat ioctls: move to ->compat_ioctl()")
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
The intel-pt-events.py script displays only the last of consecutive switch
statements but that may not be the last switch event for the CPU. Fix by
keeping a dictionary of last context switch keyed by CPU, and make it
possible to see all switch events by adding option --all-switch-events.
Fixes: a92bf335fd82eeee ("perf scripts python: intel-pt-events.py: Add branches to script")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211215080636.149562-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Hugh Dickins reported the following
My tmpfs swapping load (tweaked to use huge pages more heavily
than in real life) is far from being a realistic load: but it was
notably slowed down by your throttling mods in 5.16-rc, and this
patch makes it well again - thanks.
But: it very quickly hit NULL pointer until I changed that last
line to
if (first_pgdat)
consider_reclaim_throttle(first_pgdat, sc);
The likely issue is that huge pages are a major component of the test
workload. When this is the case, first_pgdat may never get set if
compaction is ready to continue due to this check
if (IS_ENABLED(CONFIG_COMPACTION) &&
sc->order > PAGE_ALLOC_COSTLY_ORDER &&
compaction_ready(zone, sc)) {
sc->compaction_ready = true;
continue;
}
If this was true for every zone in the zonelist, first_pgdat would never
get set resulting in a NULL pointer exception.
Link: https://lkml.kernel.org/r/20211209095453.GM3366@techsingularity.net
Fixes: 1b4e3f26f9f75 ("mm: vmscan: Reduce throttling due to a failure to make progress")
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@surriel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The spaceball.c module was not properly parsing the movement reports
coming from the device. The code read axis data as signed 16-bit
little-endian values starting at offset 2.
In fact, axis data in Spaceball movement reports are signed 16-bit
big-endian values starting at offset 3. This was determined first by
visually inspecting the data packets, and later verified by consulting:
http://spacemice.org/pdf/SpaceBall_2003-3003_Protocol.pdf
If this ever worked properly, it was in the time before Git...
Signed-off-by: Leo L. Schwab <ewhac@ewhac.org>
Link: https://lore.kernel.org/r/20211221101630.1146385-1-ewhac@ewhac.org
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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