linux/kernel/events
Thomas Richter 59e63416f5 perf/core: Allow list_del during perf_event_overflow()
A PMU might use perf_sched_cb_inc() and perf_sched_cb_dec()
interface to get the PMU call back function pmu::sched_task
invoked at schedule in and schedule out. This is achieved
by walking along the list anchored by sched_cb_list.

The following scenario might lead to a list corruption.

   perf_pmu_sched_task()
      for_each_list_entry(..., &sched_cb_list)
      +--> __perf_pmu_sched_task()
           +--> event->pmu->sched_task())
                +--> PMU_push_sample()
                     +--> perf_event_overflow()
                          +--> __perf_event_overflow()
                               +--> pmu->stop()
                                    +--> perf_sched_cb_dec()
                                         remove entry from sched_cb_list
                                         while list node in use.

This happens when ioctl(fd, PERF_EVENT_IOC_REFRESH, xxx) has been
invoked and perf_event::event_limit hits zero.

Prevent the list corruption and convert for_each_list_entry()
to for_each_list_entry_safe().

Fixes: bd27568117 ("perf: Rewrite core context handling")
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260908105637.627004-1-tmricht@linux.ibm.com
2026-09-10 10:22:50 +02:00
..
callchain.c perf: sched: Fix perf crash with new is_user_task() helper 2026-01-30 23:06:07 +01:00
core.c perf/core: Allow list_del during perf_event_overflow() 2026-09-10 10:22:50 +02:00
hw_breakpoint_test.c perf/hw_breakpoint: remove MODULE_LICENSE in non-modules 2023-04-13 13:13:52 -07:00
hw_breakpoint.c Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
internal.h perf/core: Fix deadlock in perf_mmap() failure path 2026-05-05 12:47:20 +02:00
Makefile perf/hw_breakpoint: Add KUnit test for constraints accounting 2022-08-30 10:56:20 +02:00
ring_buffer.c perf/core: Skip empty AUX records with only format flags 2026-09-02 09:18:00 +02:00
uprobes.c mm.git review status for linus..mm-stable 2026-08-27 09:17:06 -07:00