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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-08-26 08:59:50 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-08-26 08:59:50 -0700 |
| commit | 53ede64de3da17f76628b493f5e19a01804939d3 (patch) | |
| tree | d30cf6f8249781a4867280558cd61999201bc2e5 /kernel | |
| parent | b3242dba9ff285962fe84d1135cafe9383d721f0 (diff) | |
| parent | 64aee2a965cf2954a038b5522f11d2cd2f0f8f3e (diff) | |
| download | lwn-53ede64de3da17f76628b493f5e19a01804939d3.tar.gz lwn-53ede64de3da17f76628b493f5e19a01804939d3.zip | |
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fix from Ingo Molnar:
"A single fix to not allow nonsensical event groups that result in
kernel warnings"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix group {cpu,task} validation
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/events/core.c | 39 |
1 files changed, 19 insertions, 20 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index ee20d4c546b5..3504125871d2 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -10032,28 +10032,27 @@ SYSCALL_DEFINE5(perf_event_open, goto err_context; /* - * Do not allow to attach to a group in a different - * task or CPU context: + * Make sure we're both events for the same CPU; + * grouping events for different CPUs is broken; since + * you can never concurrently schedule them anyhow. */ - if (move_group) { - /* - * Make sure we're both on the same task, or both - * per-cpu events. - */ - if (group_leader->ctx->task != ctx->task) - goto err_context; + if (group_leader->cpu != event->cpu) + goto err_context; - /* - * Make sure we're both events for the same CPU; - * grouping events for different CPUs is broken; since - * you can never concurrently schedule them anyhow. - */ - if (group_leader->cpu != event->cpu) - goto err_context; - } else { - if (group_leader->ctx != ctx) - goto err_context; - } + /* + * Make sure we're both on the same task, or both + * per-CPU events. + */ + if (group_leader->ctx->task != ctx->task) + goto err_context; + + /* + * Do not allow to attach to a group in a different task + * or CPU context. If we're moving SW events, we'll fix + * this up later, so allow that. + */ + if (!move_group && group_leader->ctx != ctx) + goto err_context; /* * Only a group leader can be exclusive or pinned |