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Linux kernel
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Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix potential NULL pointer dereference in the auxtrace option parser
- Fix access to PID in an array when setting a PID filter in 'perf ftrace'
- Fix error return code in the 'perf data' tool and in maps__clone(),
found using a static analysis tool from Huawei
* tag 'perf-tools-fixes-for-v5.12-2021-04-25' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf map: Fix error return code in maps__clone()
perf ftrace: Fix access to pid in array when setting a pid filter
perf auxtrace: Fix potential NULL pointer dereference
perf data: Fix error return code in perf_data__create_dir()
Pull x86 perf fixes from Borislav Petkov:
- Fix Broadwell Xeon's stepping in the PEBS isolation table of CPUs
- Fix a panic when initializing perf uncore machinery on Haswell and
Broadwell servers
* tag 'perf_urgent_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/kvm: Fix Broadwell Xeon stepping in isolation_ucodes[]
perf/x86/intel/uncore: Remove uncore extra PCI dev HSWEP_PCI_PCU_3
Although 'err' has been initialized to -ENOMEM, but it will be reassigned
by the "err = unwind__prepare_access(...)" statement in the for loop. So
that, the value of 'err' is unknown when map__clone() failed.
Fixes: 6c502584438bda63 ("perf unwind: Call unwind__prepare_access for forked thread")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhen Lei <thunder.leizhen@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>
Cc: zhen lei <thunder.leizhen@huawei.com>
Link: http://lore.kernel.org/lkml/20210415092744.3793-1-thunder.leizhen@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull locking fix from Borislav Petkov:
"Fix ordering in the queued writer lock's slowpath"
* tag 'locking_urgent_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/qrwlock: Fix ordering in queued_write_lock_slowpath()
The only stepping of Broadwell Xeon parts is stepping 1. Fix the
relevant isolation_ucodes[] entry, which previously enumerated
stepping 2.
Although the original commit was characterized as an optimization, it
is also a workaround for a correctness issue.
If a PMI arrives between kvm's call to perf_guest_get_msrs() and the
subsequent VM-entry, a stale value for the IA32_PEBS_ENABLE MSR may be
restored at the next VM-exit. This is because, unbeknownst to kvm, PMI
throttling may clear bits in the IA32_PEBS_ENABLE MSR. CPUs with "PEBS
isolation" don't suffer from this issue, because perf_guest_get_msrs()
doesn't report the IA32_PEBS_ENABLE value.
Fixes: 9b545c04abd4f ("perf/x86/kvm: Avoid unnecessary work in guest filtering")
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Peter Shier <pshier@google.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Link: https://lkml.kernel.org/r/20210422001834.1748319-1-jmattson@google.com
Command 'perf ftrace -v -- ls' fails in s390 (at least 5.12.0rc6).
The root cause is a missing pointer dereference which causes an
array element address to be used as PID.
Fix this by extracting the PID.
Output before:
# ./perf ftrace -v -- ls
function_graph tracer is used
write '-263732416' to tracing/set_ftrace_pid failed: Invalid argument
failed to set ftrace pid
#
Output after:
./perf ftrace -v -- ls
function_graph tracer is used
# tracer: function_graph
#
# CPU DURATION FUNCTION CALLS
# | | | | | | |
4) | rcu_read_lock_sched_held() {
4) 0.552 us | rcu_lockdep_current_cpu_online();
4) 6.124 us | }
Reported-by: Alexander Schmidt <alexschm@de.ibm.com>
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20210421120400.2126433-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull scheduler fix from Borislav Petkov:
"Fix a typo in a macro ifdeffery"
* tag 'sched_urgent_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
preempt/dynamic: Fix typo in macro conditional statement
While this code is executed with the wait_lock held, a reader can
acquire the lock without holding wait_lock. The writer side loops
checking the value with the atomic_cond_read_acquire(), but only truly
acquires the lock when the compare-and-exchange is completed
successfully which isn’t ordered. This exposes the window between the
acquire and the cmpxchg to an A-B-A problem which allows reads
following the lock acquisition to observe values speculatively before
the write lock is truly acquired.
We've seen a problem in epoll where the reader does a xchg while
holding the read lock, but the writer can see a value change out from
under it.
Writer | Reader
--------------------------------------------------------------------------------
ep_scan_ready_list() |
|- write_lock_irq() |
|- queued_write_lock_slowpath() |
|- atomic_cond_read_acquire() |
| read_lock_irqsave(&ep->lock, flags);
--> (observes value before unlock) | chain_epi_lockless()
| | epi->next = xchg(&ep->ovflist, epi);
| | read_unlock_irqrestore(&ep->lock, flags);
| |
| atomic_cmpxchg_relaxed() |
|-- READ_ONCE(ep->ovflist); |
A core can order the read of the ovflist ahead of the
atomic_cmpxchg_relaxed(). Switching the cmpxchg to use acquire
semantics addresses this issue at which point the atomic_cond_read can
be switched to use relaxed semantics.
Fixes: b519b56e378ee ("locking/qrwlock: Use atomic_cond_read_acquire() when spinning in qrwlock")
Signed-off-by: Ali Saidi <alisaidi@amazon.com>
[peterz: use try_cmpxchg()]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Tested-by: Steve Capper <steve.capper@arm.com>
There may be a kernel panic on the Haswell server and the Broadwell
server, if the snbep_pci2phy_map_init() return error.
The uncore_extra_pci_dev[HSWEP_PCI_PCU_3] is used in the cpu_init() to
detect the existence of the SBOX, which is a MSR type of PMON unit.
The uncore_extra_pci_dev is allocated in the uncore_pci_init(). If the
snbep_pci2phy_map_init() returns error, perf doesn't initialize the
PCI type of the PMON units, so the uncore_extra_pci_dev will not be
allocated. But perf may continue initializing the MSR type of PMON
units. A null dereference kernel panic will be triggered.
The sockets in a Haswell server or a Broadwell server are identical.
Only need to detect the existence of the SBOX once.
Current perf probes all available PCU devices and stores them into the
uncore_extra_pci_dev. It's unnecessary.
Use the pci_get_device() to replace the uncore_extra_pci_dev. Only
detect the existence of the SBOX on the first available PCU device once.
Factor out hswep_has_limit_sbox(), since the Haswell server and the
Broadwell server uses the same way to detect the existence of the SBOX.
Add some macros to replace the magic number.
Fixes: 5306c31c5733 ("perf/x86/uncore/hsw-ep: Handle systems with only two SBOXes")
Reported-by: Steve Wahl <steve.wahl@hpe.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Steve Wahl <steve.wahl@hpe.com>
Link: https://lkml.kernel.org/r/1618521764-100923-1-git-send-email-kan.liang@linux.intel.com
In the function auxtrace_parse_snapshot_options(), the callback pointer
"itr->parse_snapshot_options" can be NULL if it has not been set during
the AUX record initialization. This can cause tool crashing if the
callback pointer "itr->parse_snapshot_options" is dereferenced without
performing NULL check.
Add a NULL check for the pointer "itr->parse_snapshot_options" before
invoke the callback.
Fixes: d20031bb63dd6dde ("perf tools: Add AUX area tracing Snapshot Mode")
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@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: Tiezhu Yang <yangtiezhu@loongson.cn>
Link: http://lore.kernel.org/lkml/20210420151554.2031768-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull x86 fix from Borislav Petkov:
"Fix an out-of-bounds memory access when setting up a crash kernel with
kexec"
* tag 'x86_urgent_for_v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/crash: Fix crash_setup_memmap_entries() out-of-bounds access
Commit 40607ee97e4e ("preempt/dynamic: Provide irqentry_exit_cond_resched()
static call") tried to provide irqentry_exit_cond_resched() static call
in irqentry_exit, but has a typo in macro conditional statement.
Fixes: 40607ee97e4e ("preempt/dynamic: Provide irqentry_exit_cond_resched() static call")
Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210410073523.5493-1-zhouzhouyi@gmail.com
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