25 Jul, 2019
1 commit
-
Some hardware PMU drivers will override perf_event.cpu inside their
event_init callback. This causes a lockdep splat when initialized through
the kernel API:WARNING: CPU: 0 PID: 250 at kernel/events/core.c:2917 ctx_sched_out+0x78/0x208
pc : ctx_sched_out+0x78/0x208
Call trace:
ctx_sched_out+0x78/0x208
__perf_install_in_context+0x160/0x248
remote_function+0x58/0x68
generic_exec_single+0x100/0x180
smp_call_function_single+0x174/0x1b8
perf_install_in_context+0x178/0x188
perf_event_create_kernel_counter+0x118/0x160Fix this by calling perf_install_in_context with event->cpu, just like
perf_event_openSigned-off-by: Leonard Crestez
Signed-off-by: Peter Zijlstra (Intel)
Reviewed-by: Mark Rutland
Cc: Alexander Shishkin
Cc: Arnaldo Carvalho de Melo
Cc: Frank Li
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Namhyung Kim
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Will Deacon
Link: https://lkml.kernel.org/r/c4ebe0503623066896d7046def4d6b1e06e0eb2e.1563972056.git.leonard.crestez@nxp.com
Signed-off-by: Ingo Molnar
20 Jul, 2019
1 commit
-
Pull misc vfs updates from Al Viro:
"Assorted stuff"* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
perf_event_get(): don't bother with fget_raw()
vfs: update d_make_root() description
13 Jul, 2019
2 commits
-
So far, we tried to disallow grouping exclusive events for the fear of
complications they would cause with moving between contexts. Specifically,
moving a software group to a hardware context would violate the exclusivity
rules if both groups contain matching exclusive events.This attempt was, however, unsuccessful: the check that we have in the
perf_event_open() syscall is both wrong (looks at wrong PMU) and
insufficient (group leader may still be exclusive), as can be illustrated
by running:$ perf record -e '{intel_pt//,cycles}' uname
$ perf record -e '{cycles,intel_pt//}' unameultimately successfully.
Furthermore, we are completely free to trigger the exclusivity violation
by:perf -e '{cycles,intel_pt//}' -e '{intel_pt//,instructions}'
even though the helpful perf record will not allow that, the ABI will.
The warning later in the perf_event_open() path will also not trigger, because
it's also wrong.Fix all this by validating the original group before moving, getting rid
of broken safeguards and placing a useful one to perf_install_in_context().Signed-off-by: Alexander Shishkin
Signed-off-by: Peter Zijlstra (Intel)
Cc:
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Cc: mathieu.poirier@linaro.org
Cc: will.deacon@arm.com
Fixes: bed5b25ad9c8a ("perf: Add a pmu capability for "exclusive" events")
Link: https://lkml.kernel.org/r/20190701110755.24646-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar -
Syzcaller reported the following Use-after-Free bug:
close() clone()
copy_process()
perf_event_init_task()
perf_event_init_context()
mutex_lock(parent_ctx->mutex)
inherit_task_group()
inherit_group()
inherit_event()
mutex_lock(event->child_mutex)
// expose event on child list
list_add_tail()
mutex_unlock(event->child_mutex)
mutex_unlock(parent_ctx->mutex)...
goto bad_fork_*bad_fork_cleanup_perf:
perf_event_free_task()perf_release()
perf_event_release_kernel()
list_for_each_entry()
mutex_lock(ctx->mutex)
mutex_lock(event->child_mutex)
// event is from the failing inherit
// on the other CPU
perf_remove_from_context()
list_move()
mutex_unlock(event->child_mutex)
mutex_unlock(ctx->mutex)mutex_lock(ctx->mutex)
list_for_each_entry_safe()
// event already stolen
mutex_unlock(ctx->mutex)delayed_free_task()
free_task()list_for_each_entry_safe()
list_del()
free_event()
_free_event()
// and so event->hw.target
// is the already freed failed clone()
if (event->hw.target)
put_task_struct(event->hw.target)
// WHOOPSIE, already quite deadWhich puts the lie to the the comment on perf_event_free_task():
'unexposed, unused context' not so much.Which is a 'fun' confluence of fail; copy_process() doing an
unconditional free_task() and not respecting refcounts, and perf having
creative locking. In particular:82d94856fa22 ("perf/core: Fix lock inversion between perf,trace,cpuhp")
seems to have overlooked this 'fun' parade.
Solve it by using the fact that detached events still have a reference
count on their (previous) context. With this perf_event_free_task()
can detect when events have escaped and wait for their destruction.Debugged-by: Alexander Shishkin
Reported-by: syzbot+a24c397a29ad22d86c98@syzkaller.appspotmail.com
Signed-off-by: Peter Zijlstra (Intel)
Acked-by: Mark Rutland
Cc:
Cc: Alexander Shishkin
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Fixes: 82d94856fa22 ("perf/core: Fix lock inversion between perf,trace,cpuhp")
Signed-off-by: Ingo Molnar
10 Jul, 2019
1 commit
-
Pull perf updates from Ingo Molnar:
"The main changes in this cycle on the kernel side were:- CPU PMU and uncore driver updates to Intel Snow Ridge, IceLake,
KabyLake, AmberLake and WhiskeyLake CPUs.- Rework the MSR probing infrastructure to make it more robust, make
it work better on virtualized systems and to better expose it on
sysfs.- Rework PMU attributes group support based on the feedback from
Greg. The core sysfs patch that adds sysfs_update_groups() was
acked by Greg.There's a lot of perf tooling changes as well, all around the place:
- vendor updates to Intel, cs-etm (ARM), ARM64, s390,
- various enhancements to Intel PT tooling support:
- Improve CBR (Core to Bus Ratio) packets support.
- Export power and ptwrite events to sqlite and postgresql.
- Add support for decoding PEBS via PT packets.
- Add support for samples to contain IPC ratio, collecting cycles
information from CYC packets, showing the IPC info periodically
- Allow using time ranges- lots of updates to perf pmu, perf stat, perf trace, eBPF support,
perf record, perf diff, etc. - please see the shortlog and Git log
for details"* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (252 commits)
tools arch x86: Sync asm/cpufeatures.h with the with the kernel
tools build: Check if gettid() is available before providing helper
perf jvmti: Address gcc string overflow warning for strncpy()
perf python: Remove -fstack-protector-strong if clang doesn't have it
perf annotate TUI browser: Do not use member from variable within its own initialization
perf tests: Fix record+probe_libc_inet_pton.sh for powerpc64
perf evsel: Do not rely on errno values for precise_ip fallback
perf thread: Allow references to thread objects after machine__exit()
perf header: Assign proper ff->ph in perf_event__synthesize_features()
tools arch kvm: Sync kvm headers with the kernel sources
perf script: Allow specifying the files to process guest samples
perf tools metric: Don't include duration_time in group
perf list: Avoid extra : for --raw metrics
perf vendor events intel: Metric fixes for SKX/CLX
perf tools: Fix typos / broken sentences
perf jevents: Add support for Hisi hip08 L3C PMU aliasing
perf jevents: Add support for Hisi hip08 HHA PMU aliasing
perf jevents: Add support for Hisi hip08 DDRC PMU aliasing
perf pmu: Support more complex PMU event aliasing
perf diff: Documentation -c cycles option
...
09 Jul, 2019
4 commits
-
…iederm/user-namespace
Pull force_sig() argument change from Eric Biederman:
"A source of error over the years has been that force_sig has taken a
task parameter when it is only safe to use force_sig with the current
task.The force_sig function is built for delivering synchronous signals
such as SIGSEGV where the userspace application caused a synchronous
fault (such as a page fault) and the kernel responded with a signal.Because the name force_sig does not make this clear, and because the
force_sig takes a task parameter the function force_sig has been
abused for sending other kinds of signals over the years. Slowly those
have been fixed when the oopses have been tracked down.This set of changes fixes the remaining abusers of force_sig and
carefully rips out the task parameter from force_sig and friends
making this kind of error almost impossible in the future"* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits)
signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus
signal: Remove the signal number and task parameters from force_sig_info
signal: Factor force_sig_info_to_task out of force_sig_info
signal: Generate the siginfo in force_sig
signal: Move the computation of force into send_signal and correct it.
signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal
signal: Remove the task parameter from force_sig_fault
signal: Use force_sig_fault_to_task for the two calls that don't deliver to current
signal: Explicitly call force_sig_fault on current
signal/unicore32: Remove tsk parameter from __do_user_fault
signal/arm: Remove tsk parameter from __do_user_fault
signal/arm: Remove tsk parameter from ptrace_break
signal/nds32: Remove tsk parameter from send_sigtrap
signal/riscv: Remove tsk parameter from do_trap
signal/sh: Remove tsk parameter from force_sig_info_fault
signal/um: Remove task parameter from send_sigtrap
signal/x86: Remove task parameter from send_sigtrap
signal: Remove task parameter from force_sig_mceerr
signal: Remove task parameter from force_sig
signal: Remove task parameter from force_sigsegv
... -
Pull RCU updates from Ingo Molnar:
"The changes in this cycle are:- RCU flavor consolidation cleanups and optmizations
- Documentation updates
- Miscellaneous fixes
- SRCU updates
- RCU-sync flavor consolidation
- Torture-test updates
- Linux-kernel memory-consistency-model updates, most notably the
addition of plain C-language accesses"* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (61 commits)
tools/memory-model: Improve data-race detection
tools/memory-model: Change definition of rcu-fence
tools/memory-model: Expand definition of barrier
tools/memory-model: Do not use "herd" to refer to "herd7"
tools/memory-model: Fix comment in MP+poonceonces.litmus
Documentation: atomic_t.txt: Explain ordering provided by smp_mb__{before,after}_atomic()
rcu: Don't return a value from rcu_assign_pointer()
rcu: Force inlining of rcu_read_lock()
rcu: Fix irritating whitespace error in rcu_assign_pointer()
rcu: Upgrade sync_exp_work_done() to smp_mb()
rcutorture: Upper case solves the case of the vanishing NULL pointer
torture: Suppress propagating trace_printk() warning
rcutorture: Dump trace buffer for callback pipe drain failures
torture: Add --trust-make to suppress "make clean"
torture: Make --cpus override idleness calculations
torture: Run kernel build in source directory
torture: Add function graph-tracing cheat sheet
torture: Capture qemu output
rcutorture: Tweak kvm options
rcutorture: Add trivial RCU implementation
... -
Pull timer updates from Thomas Gleixner:
"The timer and timekeeping departement delivers:Core:
- The consolidation of the VDSO code into a generic library including
the conversion of x86 and ARM64. Conversion of ARM and MIPS are en
route through the relevant maintainer trees and should end up in
5.4.This gets rid of the unnecessary different copies of the same code
and brings all architectures on the same level of VDSO
functionality.- Make the NTP user space interface more robust by restricting the
TAI offset to prevent undefined behaviour. Includes a selftest.- Validate user input in the compat settimeofday() syscall to catch
invalid values which would be turned into valid values by a
multiplication overflow- Consolidate the time accessors
- Small fixes, improvements and cleanups all over the place
Drivers:
- Support for the NXP system counter, TI davinci timer
- Move the Microsoft HyperV clocksource/events code into the
drivers/clocksource directory so it can be shared between x86 and
ARM64.- Overhaul of the Tegra driver
- Delay timer support for IXP4xx
- Small fixes, improvements and cleanups as usual"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits)
time: Validate user input in compat_settimeofday()
timer: Document TIMER_PINNED
clocksource/drivers: Continue making Hyper-V clocksource ISA agnostic
clocksource/drivers: Make Hyper-V clocksource ISA agnostic
MAINTAINERS: Fix Andy's surname and the directory entries of VDSO
hrtimer: Use a bullet for the returns bullet list
arm64: vdso: Fix compilation with clang older than 8
arm64: compat: Fix __arch_get_hw_counter() implementation
arm64: Fix __arch_get_hw_counter() implementation
lib/vdso: Make delta calculation work correctly
MAINTAINERS: Add entry for the generic VDSO library
arm64: compat: No need for pre-ARMv7 barriers on an ARMv8 system
arm64: vdso: Remove unnecessary asm-offsets.c definitions
vdso: Remove superfluous #ifdef __KERNEL__ in vdso/datapage.h
clocksource/drivers/davinci: Add support for clocksource
clocksource/drivers/davinci: Add support for clockevents
clocksource/drivers/tegra: Set up maximum-ticks limit properly
clocksource/drivers/tegra: Cycles can't be 0
clocksource/drivers/tegra: Restore base address before cleanup
clocksource/drivers/tegra: Add verbose definition for 1MHz constant
... -
Signed-off-by: Ingo Molnar
29 Jun, 2019
1 commit
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…k/linux-rcu into core/rcu
Pull rcu/next + tools/memory-model changes from Paul E. McKenney:
- RCU flavor consolidation cleanups and optmizations
- Documentation updates
- Miscellaneous fixes
- SRCU updates
- RCU-sync flavor consolidation
- Torture-test updates
- Linux-kernel memory-consistency-model updates, most notably the addition of plain C-language accessesSigned-off-by: Ingo Molnar <mingo@kernel.org>
27 Jun, 2019
1 commit
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... since we immediately follow that with check that it *is* an
opened perf file, with O_PATH ones ending with with the same
-EBADF we'd get for descriptor that isn't opened at all.Signed-off-by: Al Viro
25 Jun, 2019
3 commits
-
Currently perf_rotate_context assumes that if the context's nr_events !=
nr_active a rotation is necessary for perf event multiplexing. With
cgroups, nr_events is the total count of events for all cgroups and
nr_active will not include events in a cgroup other than the current
task's. This makes rotation appear necessary for cgroups when it is not.Add a perf_event_context flag that is set when rotation is necessary.
Clear the flag during sched_out and set it when a flexible sched_in
fails due to resources.Signed-off-by: Ian Rogers
Signed-off-by: Peter Zijlstra (Intel)
Cc: Alexander Shishkin
Cc: Arnaldo Carvalho de Melo
Cc: Arnaldo Carvalho de Melo
Cc: Borislav Petkov
Cc: Jiri Olsa
Cc: Kan Liang
Cc: Linus Torvalds
Cc: Namhyung Kim
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Link: https://lkml.kernel.org/r/20190601082722.44543-1-irogers@google.com
Signed-off-by: Ingo Molnar -
The perf fuzzer caused Skylake machine to crash:
[ 9680.085831] Call Trace:
[ 9680.088301]
[ 9680.090363] perf_output_sample_regs+0x43/0xa0
[ 9680.094928] perf_output_sample+0x3aa/0x7a0
[ 9680.099181] perf_event_output_forward+0x53/0x80
[ 9680.103917] __perf_event_overflow+0x52/0xf0
[ 9680.108266] ? perf_trace_run_bpf_submit+0xc0/0xc0
[ 9680.113108] perf_swevent_hrtimer+0xe2/0x150
[ 9680.117475] ? check_preempt_wakeup+0x181/0x230
[ 9680.122091] ? check_preempt_curr+0x62/0x90
[ 9680.126361] ? ttwu_do_wakeup+0x19/0x140
[ 9680.130355] ? try_to_wake_up+0x54/0x460
[ 9680.134366] ? reweight_entity+0x15b/0x1a0
[ 9680.138559] ? __queue_work+0x103/0x3f0
[ 9680.142472] ? update_dl_rq_load_avg+0x1cd/0x270
[ 9680.147194] ? timerqueue_del+0x1e/0x40
[ 9680.151092] ? __remove_hrtimer+0x35/0x70
[ 9680.155191] __hrtimer_run_queues+0x100/0x280
[ 9680.159658] hrtimer_interrupt+0x100/0x220
[ 9680.163835] smp_apic_timer_interrupt+0x6a/0x140
[ 9680.168555] apic_timer_interrupt+0xf/0x20
[ 9680.172756]The XMM registers can only be collected by PEBS hardware events on the
platforms with PEBS baseline support, e.g. Icelake, not software/probe
events.Add capabilities flag PERF_PMU_CAP_EXTENDED_REGS to indicate the PMU
which support extended registers. For X86, the extended registers are
XMM registers.Add has_extended_regs() to check if extended registers are applied.
The generic code define the mask of extended registers as 0 if arch
headers haven't overridden it.Originally-by: Peter Zijlstra (Intel)
Reported-by: Vince Weaver
Signed-off-by: Kan Liang
Signed-off-by: Peter Zijlstra (Intel)
Cc: Alexander Shishkin
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Fixes: 878068ea270e ("perf/x86: Support outputting XMM registers")
Link: https://lkml.kernel.org/r/1559081314-9714-1-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar -
perf_event_open() limits the sample_period to 63 bits. See:
0819b2e30ccb ("perf: Limit perf_event_attr::sample_period to 63 bits")
Make ioctl() consistent with it.
Also on PowerPC, negative sample_period could cause a recursive
PMIs leading to a hang (reported when running perf-fuzzer).Signed-off-by: Ravi Bangoria
Signed-off-by: Peter Zijlstra (Intel)
Cc: Alexander Shishkin
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Cc: acme@kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: maddy@linux.vnet.ibm.com
Cc: mpe@ellerman.id.au
Fixes: 0819b2e30ccb ("perf: Limit perf_event_attr::sample_period to 63 bits")
Link: https://lkml.kernel.org/r/20190604042953.914-1-ravi.bangoria@linux.ibm.com
Signed-off-by: Ingo Molnar
22 Jun, 2019
1 commit
-
This makes boot uniformly boottime and tai uniformly clocktai, to
address the remaining oversights.Signed-off-by: Jason A. Donenfeld
Signed-off-by: Thomas Gleixner
Reviewed-by: Arnd Bergmann
Link: https://lkml.kernel.org/r/20190621203249.3909-2-Jason@zx2c4.com
17 Jun, 2019
1 commit
-
perf_sample_regs_user() uses 'current->mm' to test for the presence of
userspace, but this is insufficient, consider use_mm().A better test is: '!(current->flags & PF_KTHREAD)', exec() clears
PF_KTHREAD after it sets the new ->mm but before it drops to userspace
for the first time.Possibly obsoletes: bf05fc25f268 ("powerpc/perf: Fix oops when kthread execs user process")
Reported-by: Ravi Bangoria
Reported-by: Young Xiao
Signed-off-by: Peter Zijlstra (Intel)
Acked-by: Will Deacon
Cc: Arnaldo Carvalho de Melo
Cc: Frederic Weisbecker
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Michael Ellerman
Cc: Naveen N. Rao
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Fixes: 4018994f3d87 ("perf: Add ability to attach user level registers dump to sample")
Signed-off-by: Ingo Molnar
03 Jun, 2019
2 commits
-
Adding attr_update attribute group into pmu, to allow
having multiple attribute groups for same group name.This will allow us to update "events" or "format"
directories with attributes that depend on various
HW conditions.For example having group_format_extra group that updates
"format" directory only if pmu version is 2 and higher:static umode_t
exra_is_visible(struct kobject *kobj, struct attribute *attr, int i)
{
return x86_pmu.version >= 2 ? attr->mode : 0;
}static struct attribute_group group_format_extra = {
.name = "format",
.is_visible = exra_is_visible,
};Signed-off-by: Jiri Olsa
Signed-off-by: Peter Zijlstra (Intel)
Cc: Alexander Shishkin
Cc: Arnaldo Carvalho de Melo
Cc: Greg Kroah-Hartman
Cc: Linus Torvalds
Cc: Namhyung Kim
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Link: https://lkml.kernel.org/r/20190512155518.21468-3-jolsa@kernel.org
Signed-off-by: Ingo Molnar -
Currently, non-privileged user could only use uprobe with
kernel.perf_event_paranoid = -1
However, setting perf_event_paranoid to -1 leaks other users' processes to
non-privileged uprobes.To introduce proper permission control of uprobes, we are building the
following system:A daemon with CAP_SYS_ADMIN is in charge to create uprobes via tracefs;
Users asks the daemon to create uprobes;
Then user can attach uprobe only to processes owned by the user.This patch allows non-privileged user to attach uprobe to processes owned
by the user.The following example shows how to use uprobe with non-privileged user.
This is based on Brendan's blog post [1]1. Create uprobe with root:
sudo perf probe -x 'readline%return +0($retval):string'
2. Then non-root user can use the uprobe as:
perf record -vvv -e probe_bash:readline__return -p sleep 20
perf script[1] http://www.brendangregg.com/blog/2015-06-28/linux-ftrace-uprobe.html
Signed-off-by: Song Liu
Signed-off-by: Peter Zijlstra (Intel)
Cc:
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Link: https://lkml.kernel.org/r/20190507161545.788381-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar
29 May, 2019
1 commit
-
Use DEFINE_STATIC_PERCPU_RWSEM() to initialize dup_mmap_sem.
Signed-off-by: Oleg Nesterov
Reviewed-by: Ingo Molnar
Signed-off-by: Paul E. McKenney
27 May, 2019
1 commit
-
All of the remaining callers pass current into force_sig so
remove the task parameter to make this obvious and to make
misuse more difficult in the future.This also makes it clear force_sig passes current into force_sig_info.
Signed-off-by: "Eric W. Biederman"
24 May, 2019
4 commits
-
While the IRQ/NMI will nest, the nest-count will be invariant over the
actual exception, since it will decrement equal to increment.This means we can -- carefully -- use a regular variable since the
typical LOAD-STORE race doesn't exist (similar to preempt_count).This optimizes the ring-buffer for all LOAD-STORE architectures, since
they need to use atomic ops to implement local_t.Suggested-by: Alexander Shishkin
Signed-off-by: Peter Zijlstra (Intel)
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Cc: acme@kernel.org
Cc: mark.rutland@arm.com
Cc: namhyung@kernel.org
Cc: yabinc@google.com
Link: http://lkml.kernel.org/r/20190517115418.481392777@infradead.org
Signed-off-by: Ingo Molnar -
We must use {READ,WRITE}_ONCE() on rb->user_page data such that
concurrent usage will see whole values. A few key sites were missing
this.Suggested-by: Yabin Cui
Signed-off-by: Peter Zijlstra (Intel)
Cc: Alexander Shishkin
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Cc: acme@kernel.org
Cc: mark.rutland@arm.com
Cc: namhyung@kernel.org
Fixes: 7b732a750477 ("perf_counter: new output ABI - part 1")
Link: http://lkml.kernel.org/r/20190517115418.394192145@infradead.org
Signed-off-by: Ingo Molnar -
Similar to how decrementing rb->next too early can cause data_head to
(temporarily) be observed to go backward, so too can this happen when
we increment too late.This barrier() ensures the rb->head load happens after the increment,
both the one in the 'goto again' path, as the one from
perf_output_get_handle() -- albeit very unlikely to matter for the
latter.Suggested-by: Yabin Cui
Signed-off-by: Peter Zijlstra (Intel)
Cc: Alexander Shishkin
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Cc: acme@kernel.org
Cc: mark.rutland@arm.com
Cc: namhyung@kernel.org
Fixes: ef60777c9abd ("perf: Optimize the perf_output() path by removing IRQ-disables")
Link: http://lkml.kernel.org/r/20190517115418.309516009@infradead.org
Signed-off-by: Ingo Molnar -
In perf_output_put_handle(), an IRQ/NMI can happen in below location and
write records to the same ring buffer:...
local_dec_and_test(&rb->nest)
... user_page->data_head = head;
...In this case, a value A is written to data_head in the IRQ, then a value
B is written to data_head after the IRQ. And A > B. As a result,
data_head is temporarily decreased from A to B. And a reader may see
data_head < data_tail if it read the buffer frequently enough, which
creates unexpected behaviors.This can be fixed by moving dec(&rb->nest) to after updating data_head,
which prevents the IRQ/NMI above from updating data_head.[ Split up by peterz. ]
Signed-off-by: Yabin Cui
Signed-off-by: Peter Zijlstra (Intel)
Cc: Alexander Shishkin
Cc: Arnaldo Carvalho de Melo
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Namhyung Kim
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Cc: mark.rutland@arm.com
Fixes: ef60777c9abd ("perf: Optimize the perf_output() path by removing IRQ-disables")
Link: http://lkml.kernel.org/r/20190517115418.224478157@infradead.org
Signed-off-by: Ingo Molnar
15 May, 2019
2 commits
-
This updates each existing invalidation to use the correct mmu notifier
event that represent what is happening to the CPU page table. See the
patch which introduced the events to see the rational behind this.Link: http://lkml.kernel.org/r/20190326164747.24405-7-jglisse@redhat.com
Signed-off-by: Jérôme Glisse
Reviewed-by: Ralph Campbell
Reviewed-by: Ira Weiny
Cc: Christian König
Cc: Joonas Lahtinen
Cc: Jani Nikula
Cc: Rodrigo Vivi
Cc: Jan Kara
Cc: Andrea Arcangeli
Cc: Peter Xu
Cc: Felix Kuehling
Cc: Jason Gunthorpe
Cc: Ross Zwisler
Cc: Dan Williams
Cc: Paolo Bonzini
Cc: Radim Krcmar
Cc: Michal Hocko
Cc: Christian Koenig
Cc: John Hubbard
Cc: Arnd Bergmann
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
CPU page table update can happens for many reasons, not only as a result
of a syscall (munmap(), mprotect(), mremap(), madvise(), ...) but also as
a result of kernel activities (memory compression, reclaim, migration,
...).Users of mmu notifier API track changes to the CPU page table and take
specific action for them. While current API only provide range of virtual
address affected by the change, not why the changes is happening.This patchset do the initial mechanical convertion of all the places that
calls mmu_notifier_range_init to also provide the default MMU_NOTIFY_UNMAP
event as well as the vma if it is know (most invalidation happens against
a given vma). Passing down the vma allows the users of mmu notifier to
inspect the new vma page protection.The MMU_NOTIFY_UNMAP is always the safe default as users of mmu notifier
should assume that every for the range is going away when that event
happens. A latter patch do convert mm call path to use a more appropriate
events for each call.This is done as 2 patches so that no call site is forgotten especialy
as it uses this following coccinelle patch:%vm_mm, E3, E4)
...>@@
expression E1, E2, E3, E4;
identifier FN, VMA;
@@
FN(..., struct vm_area_struct *VMA, ...) {
}@@
expression E1, E2, E3, E4;
identifier FN, VMA;
@@
FN(...) {
struct vm_area_struct *VMA;
}@@
expression E1, E2, E3, E4;
identifier FN;
@@
FN(...) {
}
---------------------------------------------------------------------->%Applied with:
spatch --all-includes --sp-file mmu-notifier.spatch fs/proc/task_mmu.c --in-place
spatch --sp-file mmu-notifier.spatch --dir kernel/events/ --in-place
spatch --sp-file mmu-notifier.spatch --dir mm --in-placeLink: http://lkml.kernel.org/r/20190326164747.24405-6-jglisse@redhat.com
Signed-off-by: Jérôme Glisse
Reviewed-by: Ralph Campbell
Reviewed-by: Ira Weiny
Cc: Christian König
Cc: Joonas Lahtinen
Cc: Jani Nikula
Cc: Rodrigo Vivi
Cc: Jan Kara
Cc: Andrea Arcangeli
Cc: Peter Xu
Cc: Felix Kuehling
Cc: Jason Gunthorpe
Cc: Ross Zwisler
Cc: Dan Williams
Cc: Paolo Bonzini
Cc: Radim Krcmar
Cc: Michal Hocko
Cc: Christian Koenig
Cc: John Hubbard
Cc: Arnd Bergmann
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 May, 2019
1 commit
-
Pull printk updates from Petr Mladek:
- Allow state reset of printk_once() calls.
- Prevent crashes when dereferencing invalid pointers in vsprintf().
Only the first byte is checked for simplicity.- Make vsprintf warnings consistent and inlined.
- Treewide conversion of obsolete %pf, %pF to %ps, %pF printf
modifiers.- Some clean up of vsprintf and test_printf code.
* tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
lib/vsprintf: Make function pointer_string static
vsprintf: Limit the length of inlined error messages
vsprintf: Avoid confusion between invalid address and value
vsprintf: Prevent crash when dereferencing invalid pointers
vsprintf: Consolidate handling of unknown pointer specifiers
vsprintf: Factor out %pO handler as kobject_string()
vsprintf: Factor out %pV handler as va_format()
vsprintf: Factor out %p[iI] handler as ip_addr_string()
vsprintf: Do not check address of well-known strings
vsprintf: Consistent %pK handling for kptr_restrict == 0
vsprintf: Shuffle restricted_pointer()
printk: Tie printk_once / printk_deferred_once into .data.once for reset
treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively
lib/test_printf: Switch to bitmap_zalloc()
07 May, 2019
2 commits
-
Pull x86 mm updates from Ingo Molnar:
"The changes in here are:- text_poke() fixes and an extensive set of executability lockdowns,
to (hopefully) eliminate the last residual circumstances under
which we are using W|X mappings even temporarily on x86 kernels.
This required a broad range of surgery in text patching facilities,
module loading, trampoline handling and other bits.- tweak page fault messages to be more informative and more
structured.- remove DISCONTIGMEM support on x86-32 and make SPARSEMEM the
default.- reduce KASLR granularity on 5-level paging kernels from 512 GB to
1 GB.- misc other changes and updates"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
x86/mm: Initialize PGD cache during mm initialization
x86/alternatives: Add comment about module removal races
x86/kprobes: Use vmalloc special flag
x86/ftrace: Use vmalloc special flag
bpf: Use vmalloc special flag
modules: Use vmalloc special flag
mm/vmalloc: Add flag for freeing of special permsissions
mm/hibernation: Make hibernation handle unmapped pages
x86/mm/cpa: Add set_direct_map_*() functions
x86/alternatives: Remove the return value of text_poke_*()
x86/jump-label: Remove support for custom text poker
x86/modules: Avoid breaking W^X while loading modules
x86/kprobes: Set instruction page as executable
x86/ftrace: Set trampoline pages as executable
x86/kgdb: Avoid redundant comparison of patched code
x86/alternatives: Use temporary mm for text poking
x86/alternatives: Initialize temporary mm for patching
fork: Provide a function for copying init_mm
uprobes: Initialize uprobes earlier
x86/mm: Save debug registers when loading a temporary mm
... -
Pull perf updates from Ingo Molnar:
"The main kernel changes were:- add support for Intel's "adaptive PEBS v4" - which embedds LBS data
in PEBS records and can thus batch up and reduce the IRQ (NMI) rate
significantly - reducing overhead and making call-graph profiling
less intrusive.- add Intel CPU core and uncore support updates for Tremont, Icelake,
- extend the x86 PMU constraints scheduler with 'constraint ranges'
to better support Icelake hw constraints,- make x86 call-chain support work better with CONFIG_FRAME_POINTER=y
- misc other changes
Tooling changes:
- updates to the main tools: 'perf record', 'perf trace', 'perf
stat'- updated Intel and S/390 vendor events
- libtraceevent updates
- misc other updates and fixes"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (69 commits)
perf/x86: Make perf callchains work without CONFIG_FRAME_POINTER
watchdog: Fix typo in comment
perf/x86/intel: Add Tremont core PMU support
perf/x86/intel/uncore: Add Intel Icelake uncore support
perf/x86/msr: Add Icelake support
perf/x86/intel/rapl: Add Icelake support
perf/x86/intel/cstate: Add Icelake support
perf/x86/intel: Add Icelake support
perf/x86: Support constraint ranges
perf/x86/lbr: Avoid reading the LBRs when adaptive PEBS handles them
perf/x86/intel: Support adaptive PEBS v4
perf/x86/intel/ds: Extract code of event update in short period
perf/x86/intel: Extract memory code PEBS parser for reuse
perf/x86: Support outputting XMM registers
perf/x86/intel: Force resched when TFA sysctl is modified
perf/core: Add perf_pmu_resched() as global function
perf/headers: Fix stale comment for struct perf_addr_filter
perf/core: Make perf_swevent_init_cpu() static
perf/x86: Add sanity checks to x86_schedule_events()
perf/x86: Optimize x86_schedule_events()
...
03 May, 2019
1 commit
-
This recent commit:
5768402fd9c6e87 ("perf/ring_buffer: Use high order allocations for AUX buffers optimistically")
overlooked the fact that the previous one page granularity of the AUX buffer
provided an implicit double buffering capability to the PMU driver, which
went away when the entire buffer became one high-order page.Always make the full-trace mode AUX allocation at least two-part to preserve
the previous behavior and allow the implicit double buffering to continue.Reported-by: Ammy Yi
Signed-off-by: Alexander Shishkin
Acked-by: Peter Zijlstra
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Cc: adrian.hunter@intel.com
Fixes: 5768402fd9c6e87 ("perf/ring_buffer: Use high order allocations for AUX buffers optimistically")
Link: http://lkml.kernel.org/r/20190503085536.24119-2-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar
30 Apr, 2019
1 commit
-
In order to have a separate address space for text poking, we need to
duplicate init_mm early during start_kernel(). This, however, introduces
a problem since uprobes functions are called from dup_mmap(), but
uprobes is still not initialized in this early stage.Since uprobes initialization is necassary for fork, and since all the
dependant initialization has been done when fork is initialized (percpu
and vmalloc), move uprobes initialization to fork_init(). It does not
seem uprobes introduces any security problem for the poking_mm.Crash and burn if uprobes initialization fails, similarly to other early
initializations. Change the init_probes() name to probes_init() to match
other early initialization functions name convention.Reported-by: kernel test robot
Signed-off-by: Nadav Amit
Signed-off-by: Peter Zijlstra (Intel)
Cc: Andy Lutomirski
Cc: Arnaldo Carvalho de Melo
Cc: Borislav Petkov
Cc: Dave Hansen
Cc: H. Peter Anvin
Cc: Linus Torvalds
Cc: Rick Edgecombe
Cc: Rik van Riel
Cc: Thomas Gleixner
Cc: akpm@linux-foundation.org
Cc: ard.biesheuvel@linaro.org
Cc: deneen.t.dock@intel.com
Cc: kernel-hardening@lists.openwall.com
Cc: kristen@linux.intel.com
Cc: linux_dti@icloud.com
Cc: will.deacon@arm.com
Link: https://lkml.kernel.org/r/20190426232303.28381-6-nadav.amit@gmail.com
Signed-off-by: Ingo Molnar
16 Apr, 2019
5 commits
-
This patch add perf_pmu_resched() a global function that can be called
to force rescheduling of events for a given PMU. The function locks
both cpuctx and task_ctx internally. This will be used by a subsequent
patch.Signed-off-by: Stephane Eranian
[ Simplified the calling convention. ]
Signed-off-by: Peter Zijlstra (Intel)
Cc: Alexander Shishkin
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Vince Weaver
Cc: kan.liang@intel.com
Cc: nelson.dsouza@intel.com
Cc: tonyj@suse.com
Link: https://lkml.kernel.org/r/20190408173252.37932-2-eranian@google.com
Signed-off-by: Ingo Molnar -
Signed-off-by: Ingo Molnar
-
The following commit:
1627314fb54a33e ("perf: Suppress AUX/OVERWRITE records")
has an unintended side-effect of also suppressing all AUX records with no flags
and non-zero size, so all the regular records in the full trace mode.
This breaks some use cases for people.Fix this by restoring "regular" AUX records.
Reported-by: Ben Gainey
Tested-by: Ben Gainey
Signed-off-by: Alexander Shishkin
Signed-off-by: Peter Zijlstra (Intel)
Cc:
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Fixes: 1627314fb54a33e ("perf: Suppress AUX/OVERWRITE records")
Link: https://lkml.kernel.org/r/20190329091338.29999-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar -
The following recent commit:
c60f83b813e5 ("perf, pt, coresight: Fix address filters for vmas with non-zero offset")
changes the address filtering logic to communicate filter ranges to the PMU driver
via a single address range object, instead of having the driver do the final bit of
math.That change forgets to take into account kernel filters, which are not calculated
the same way as DSO based filters.Fix that by passing the kernel filters the same way as file-based filters.
This doesn't require any additional changes in the drivers.Reported-by: Adrian Hunter
Signed-off-by: Alexander Shishkin
Signed-off-by: Peter Zijlstra (Intel)
Cc: Arnaldo Carvalho de Melo
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Fixes: c60f83b813e5 ("perf, pt, coresight: Fix address filters for vmas with non-zero offset")
Link: https://lkml.kernel.org/r/20190329091212.29870-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar -
Signed-off-by: Ingo Molnar
12 Apr, 2019
1 commit
-
Thomas-Mich Richter reported he triggered a WARN()ing from event_function_local()
on his s390. The problem boils down to:CPU-A CPU-B
perf_event_overflow()
perf_event_disable_inatomic()
@pending_disable = 1
irq_work_queue();sched-out
event_sched_out()
@pending_disable = 0sched-in
perf_event_overflow()
perf_event_disable_inatomic()
@pending_disable = 1;
irq_work_queue(); // FAILSirq_work_run()
perf_pending_event()
if (@pending_disable)
perf_event_disable_local(); // WHOOPSThe problem exists in generic, but s390 is particularly sensitive
because it doesn't implement arch_irq_work_raise(), nor does it call
irq_work_run() from it's PMU interrupt handler (nor would that be
sufficient in this case, because s390 also generates
perf_event_overflow() from pmu::stop). Add to that the fact that s390
is a virtual architecture and (virtual) CPU-A can stall long enough
for the above race to happen, even if it would self-IPI.Adding a irq_work_sync() to event_sched_in() would work for all hardare
PMUs that properly use irq_work_run() but fails for software PMUs.Instead encode the CPU number in @pending_disable, such that we can
tell which CPU requested the disable. This then allows us to detect
the above scenario and even redirect the IPI to make up for the failed
queue.Reported-by: Thomas-Mich Richter
Tested-by: Thomas Richter
Signed-off-by: Peter Zijlstra (Intel)
Acked-by: Mark Rutland
Cc: Alexander Shishkin
Cc: Arnaldo Carvalho de Melo
Cc: Heiko Carstens
Cc: Hendrik Brueckner
Cc: Jiri Olsa
Cc: Kees Cook
Cc: Linus Torvalds
Cc: Martin Schwidefsky
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Signed-off-by: Ingo Molnar
09 Apr, 2019
1 commit
-
%pF and %pf are functionally equivalent to %pS and %ps conversion
specifiers. The former are deprecated, therefore switch the current users
to use the preferred variant.The changes have been produced by the following command:
git grep -l '%p[fF]' | grep -v '^\(tools\|Documentation\)/' | \
while read i; do perl -i -pe 's/%pf/%ps/g; s/%pF/%pS/g;' $i; doneAnd verifying the result.
Link: http://lkml.kernel.org/r/20190325193229.23390-1-sakari.ailus@linux.intel.com
Cc: Andy Shevchenko
Cc: linux-arm-kernel@lists.infradead.org
Cc: sparclinux@vger.kernel.org
Cc: linux-um@lists.infradead.org
Cc: xen-devel@lists.xenproject.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: drbd-dev@lists.linbit.com
Cc: linux-block@vger.kernel.org
Cc: linux-mmc@vger.kernel.org
Cc: linux-nvdimm@lists.01.org
Cc: linux-pci@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: linux-btrfs@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: linux-mm@kvack.org
Cc: ceph-devel@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Sakari Ailus
Acked-by: David Sterba (for btrfs)
Acked-by: Mike Rapoport (for mm/memblock.c)
Acked-by: Bjorn Helgaas (for drivers/pci)
Acked-by: Rafael J. Wysocki
Signed-off-by: Petr Mladek
03 Apr, 2019
1 commit
-
'make W=1' causes GCC to complain:
kernel/events/core.c:11877:6: warning: no previous prototype for 'perf_swevent_init_cpu' [-Wmissing-prototypes]
It's not referenced anywhere else, make it static.
Signed-off-by: Valdis Kletnieks
Signed-off-by: Peter Zijlstra (Intel)
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Link: https://lkml.kernel.org/r/28974.1552377997@turing-police
Signed-off-by: Ingo Molnar
23 Mar, 2019
1 commit
-
…ux/kernel/git/acme/linux into perf/urgent
Pull perf/core improvements and fixes from Arnaldo:
kernel:
Stephane Eranian :
- Restore mmap record type correctly when handling PERF_RECORD_MMAP2
events, as the same template is used for all the threads interested
in mmap events, some may want just PERF_RECORD_MMAP, while some
may want the extra info in MMAP2 records.perf probe:
Adrian Hunter:
- Fix getting the kernel map, because since changes related to x86 PTI
entry trampolines handling, there are more than one kernel map.perf script:
Andi Kleen:
- Support insn output for normal samples, i.e.:
perf script -F ip,sym,insn --xed
Will fetch the sample IP from the thread address space and feed it
to Intel's XED disassembler, producing lines such as:ffffffffa4068804 native_write_msr wrmsr
ffffffffa415b95e __hrtimer_next_event_base movq 0x18(%rax), %rdxThat match 'perf annotate's output.
- Make the --cpu filter apply to PERF_RECORD_COMM/FORK/... events, in
addition to PERF_RECORD_SAMPLE.perf report:
- Add a new --samples option to save a small random number of samples
per hist entry, using a reservoir technique to select a representative
number of samples.Then allow browsing the samples using 'perf script' as part of the hist
entry context menu. This automatically adds the right filters, so only
the thread or CPU of the sample is displayed. Then we use less' search
functionality to directly jump to the time stamp of the selected sample.It uses different menus for assembler and source display. Assembler
needs xed installed and source needs debuginfo.- Fix the UI browser scripts pop up menu when there are many scripts
available.perf report:
Andi Kleen:
- Add 'time' sort option. E.g.:
% perf report --sort time,overhead,symbol --time-quantum 1ms --stdio
...
0.67% 277061.87300 [.] _dl_start
0.50% 277061.87300 [.] f1
0.50% 277061.87300 [.] f2
0.33% 277061.87300 [.] main
0.29% 277061.87300 [.] _dl_lookup_symbol_x
0.29% 277061.87300 [.] dl_main
0.29% 277061.87300 [.] do_lookup_x
0.17% 277061.87300 [.] _dl_debug_initialize
0.17% 277061.87300 [.] _dl_init_paths
0.08% 277061.87300 [.] check_match
0.04% 277061.87300 [.] _dl_count_modids
1.33% 277061.87400 [.] f1
1.33% 277061.87400 [.] f2
1.33% 277061.87400 [.] main
1.17% 277061.87500 [.] main
1.08% 277061.87500 [.] f1
1.08% 277061.87500 [.] f2
1.00% 277061.87600 [.] main
0.83% 277061.87600 [.] f1
0.83% 277061.87600 [.] f2
1.00% 277061.87700 [.] maintools headers:
Arnaldo Carvalho de Melo:
- Update x86's syscall_64.tbl, no change in tools/perf behaviour.
- Sync copies asm-generic/unistd.h and linux/in with the kernel sources.
perf data:
Jiri Olsa:
- Prep work to support having perf.data stored as a directory, with one
file per CPU, that ultimately will allow having one ring buffer reading
thread per CPU.Vendor events:
Martin Liška:
- perf PMU events for AMD Family 17h.
perf script python:
Tony Jones:
- Add python3 support for the remaining Intel PT related scripts, with
these we should have a clean build of perf with python3 while still
supporting the build with python2.libbpf:
Arnaldo Carvalho de Melo:
- Fix the build on uCLibc, adding the missing stdarg.h since we use
va_list in one typedef.Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
