Date: Tue, 24 Mar 2020 23:15:12 +0000 From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 244878] Kernel panic due to spin lock held too long Message-ID: <bug-244878-227-v8qGqVFtFD@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-244878-227@https.bugs.freebsd.org/bugzilla/> References: <bug-244878-227@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=244878 Jason A. Harmening <jah@FreeBSD.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jah@FreeBSD.org --- Comment #3 from Jason A. Harmening <jah@FreeBSD.org> --- Not a lot to go on from the backtrace. One thing that can cause this panic is if a thread calls smp_rendezvous_cpus() with local interrupts disabled: if another thread holds smp_ipi_mtx and is trying to IPI the first thread's CPU, the two threads can livelock. It doesn't look like the timer callout+in6 route expiration path that panicked should ever call smp_rendezvous_cpus() with interrupts disabled, but I think it's also possible that this thread could have been the victim of two other threads that were livelocked. r357308 added a check to HEAD (INVARIANTS kernels only) that panics if a thread enters smp_rendezvous_cpus() with interrupts disabled. If this is at all reproducible, it might be worth trying a kernel with that check backported. Also worth noting: in6_mtutimo() was completely removed from HEAD in 355888. -- You are receiving this mail because: You are the assignee for the bug.help
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