diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-09-19 10:31:36 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-09-19 10:31:36 -0700 |
| commit | 598a0c7d0932e385486b173768f03d95bf5507c8 (patch) | |
| tree | d528410bffc0297c205b55dbb2b4a012243089d7 | |
| parent | 7a5e87867e9fe043c3067a864124caf2b8e7fb99 (diff) | |
| parent | 3577af70a2ce4853d58e57d832e687d739281479 (diff) | |
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"Two kernel side fixes: a kprobes fix and a perf_remove_from_context()
fix (which does not yet fix the migration bug which is WIP)"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Fix a race condition in perf_remove_from_context()
kprobes/x86: Free 'optinsn' cache when range check fails
| -rw-r--r-- | arch/x86/kernel/kprobes/opt.c | 4 | ||||
| -rw-r--r-- | kernel/events/core.c | 10 |
2 files changed, 13 insertions, 1 deletions
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index f304773285ae..f1314d0bcf0a 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -338,8 +338,10 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op) * a relative jump. */ rel = (long)op->optinsn.insn - (long)op->kp.addr + RELATIVEJUMP_SIZE; - if (abs(rel) > 0x7fffffff) + if (abs(rel) > 0x7fffffff) { + __arch_remove_optimized_kprobe(op, 0); return -ERANGE; + } buf = (u8 *)op->optinsn.insn; diff --git a/kernel/events/core.c b/kernel/events/core.c index f9c1ed002dbc..d640a8b4dcbc 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -1524,6 +1524,11 @@ retry: */ if (ctx->is_active) { raw_spin_unlock_irq(&ctx->lock); + /* + * Reload the task pointer, it might have been changed by + * a concurrent perf_event_context_sched_out(). + */ + task = ctx->task; goto retry; } @@ -1967,6 +1972,11 @@ retry: */ if (ctx->is_active) { raw_spin_unlock_irq(&ctx->lock); + /* + * Reload the task pointer, it might have been changed by + * a concurrent perf_event_context_sched_out(). + */ + task = ctx->task; goto retry; } |