[1.4] Fix SIGCHLD race in signal handler setup#5216
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rata merged 1 commit intoopencontainers:release-1.4from Apr 2, 2026
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[1.4] Fix SIGCHLD race in signal handler setup#5216rata merged 1 commit intoopencontainers:release-1.4from
rata merged 1 commit intoopencontainers:release-1.4from
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When signal installation was moved to a goroutine for performance, containers that exited quickly could complete before SIGCHLD was registered, causing runc to hang waiting for the signal. This fix ensures SIGCHLD is registered immediately in the main thread before other signals are handled in the goroutine, maintaining performance while guaranteeing no missed SIGCHLD notifications for fast-exiting containers. Reported-by: Ayato Tokubi <atokubi@redhat.com> Signed-off-by: lifubang <lifubang@acmcoder.com> (cherry picked from commit 404181e) Signed-off-by: lifubang <lifubang@acmcoder.com>
kolyshkin
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Apr 2, 2026
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Backport #5210
When signal installation was moved to a goroutine for performance, containers that exited quickly could complete before SIGCHLD was registered, causing runc to hang waiting for the signal.
This fix ensures SIGCHLD is registered immediately in the main thread before other signals are handled in the goroutine, maintaining performance while guaranteeing no missed SIGCHLD notifications for fast-exiting containers.
Reported-by: Ayato Tokubi atokubi@redhat.com
(cherry picked from commit 404181e)