Oleg Nesterov 5211613978 kmod: don't run async usermode helper as a child of kworker thread ... call_usermodehelper_exec_sync() does fork() + wait() with "unignored" SIGCHLD. What we have missed is that this worker thread can have other children previously forked by call_usermodehelper_exec_work() without UMH_WAIT_PROC. If such a child exits in between it becomes a zombie because auto-reaping only works if SIGCHLD is ignored, and nobody can reap it (unless/until this worker thread exits too). Change the !UMH_WAIT_PROC case to use CLONE_PARENT. Note: this is only first step. All PF_KTHREAD tasks, even created by kernel_thread() should have ->parent == kthreadd by default. Fixes: bb304a5c6f ("kmod: handle UMH_WAIT_PROC from system unbound workqueue") Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Christoph Lameter <cl@linux.com> Cc: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2015-10-23 17:55:10 +09:00
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time	timekeeping: Increment clock_was_set_seq in timekeeping_init()	2015-10-16 15:50:22 +02:00
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kmod.c	kmod: don't run async usermode helper as a child of kworker thread	2015-10-23 17:55:10 +09:00
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