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From: Rich Felker <dalias@libc.org>
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Subject: Re: abort() fails to terminate PID 1 process
Date: Sun, 3 Jul 2016 18:03:05 -0400
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On Sat, Jun 18, 2016 at 10:32:23PM +0200, Karl Böhlmark wrote:
> Hi!
> 
> After running alpine-linux based docker containers for a while we noticed
> some problematic behaviour when one of our services had a memory leak
> causing the process to abort.
> 
> Instead of getting abnormal process termination we were seeing the process
> hanging at 100% cpu.
> 
> A minimal reproduction of this issue is to run
> 
> #include <stdlib.h>
> int main ()
> {
> abort();
> }
> 
> with "unshare --fork --pid" so that it runs as PID 1 in it's own PID
> namespace.
> 
> Would it be reasonable to add a fallback strategy in abort() for
> terminating processes when the signals don't have any effect?

I've improved the fallback strategy. It's not perfect yet but should
mitigate your issue:

https://git.musl-libc.org/cgit/musl/commit/?id=0c8bc102f287d3993751d80ba2dffb01e0c8bc7f

Rich