Coverity: perf_install_in_context(): Integer handling issues

[coverity-bot <keescook@chromium.org>]

Hello!

This is an experimental automated report about issues detected by Coverity
from a scan of next-20191031 as part of the linux-next weekly scan project:
https://scan.coverity.com/projects/linux-next-weekly-scan

You're getting this email because you were associated with the identified
lines of code (noted below) that were touched by recent commits:

db0503e4f675 ("perf/core: Optimize perf_install_in_event()")

Coverity reported the following:

*** CID 711630:  Integer handling issues  (NEGATIVE_RETURNS)
/kernel/events/core.c: 2683 in perf_install_in_context()
2677     	if (__perf_effective_state(event) == PERF_EVENT_STATE_OFF && ctx->nr_events) {
2678     		raw_spin_lock_irq(&ctx->lock);
2679     		if (ctx->task == TASK_TOMBSTONE) {
2680     			raw_spin_unlock_irq(&ctx->lock);
2681     			return;
2682     		}
vvv     CID 711630:  Integer handling issues  (NEGATIVE_RETURNS)
vvv     "event->cpu" is passed to a parameter that cannot be negative.
2683     		add_event_to_ctx(event, ctx);
2684     		raw_spin_unlock_irq(&ctx->lock);
2685     		return;
2686     	}
2687
2688     	if (!task) {

If this is a false positive, please let us know so we can mark it as
such, or teach the Coverity rules to be smarter. If not, please make
sure fixes get into linux-next. :) For patches fixing this, please
include these lines (but double-check the "Fixes" first):

Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 711630 ("Integer handling issues")
Fixes: db0503e4f675 ("perf/core: Optimize perf_install_in_event()")


Thanks for your attention!

-- 
Coverity-bot