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Date: Tue, 20 Oct 2015 19:17:40 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>,
        Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>,
        Denys Vlasenko <dvlasenk@redhat.com>,
        Eric Dumazet <edumazet@google.com>,
        Jan Kratochvil <jan.kratochvil@redhat.com>,
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        Kostya Serebryany <kcc@google.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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        Roland McGrath <roland@hack.frob.com>, syzkaller@googlegroups.com,
        linux-kernel@vger.kernel.org
Subject: [PATCH 0/2] wait/ptrace: always assume __WALL if the child is
	traced
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Damn. I simply do not know what should/can we do. From the change
log:

	And I can only hope that this won't break something.

yet this patch cc's -stable.


Please see the changelog, but in short: this is not a kernel bug
but unlikely we can fix all distributions, so I think we have to
change the kernel.

HOWEVER. With this change __WCLONE and __WALL have no effect for
debugger, do_wait() works as if __WALL is set if the child (natural
or not) is traced.


Jan, Pedro, could you please confirm this won't break gdb? I tried
to look into gdb-7.1, and at first glance gdb uses __WCLONE only
because __WALL doesn't work on older kernels, iow it seems to me
that gdb actually wants __WALL so this change should be fine.


Any other ideas?

Oleg.