From: ebiederm@xmission.com (Eric W. Biederman) To: Andrey Grodzovsky <andrey.grodzovsky@amd.com> Cc: <linux-kernel@vger.kernel.org>, <amd-gfx@lists.freedesktop.org>, <Alexander.Deucher@amd.com>, <Christian.Koenig@amd.com>, <David.Panariti@amd.com>, <oleg@redhat.com>, <akpm@linux-foundation.org> Subject: Re: [PATCH 1/3] signals: Allow generation of SIGKILL to exiting task. Date: Tue, 24 Apr 2018 11:10:42 -0500 [thread overview] Message-ID: <87a7tsd1q5.fsf@xmission.com> (raw) In-Reply-To: <1524583836-12130-2-git-send-email-andrey.grodzovsky@amd.com> (Andrey Grodzovsky's message of "Tue, 24 Apr 2018 11:30:34 -0400") Andrey Grodzovsky <andrey.grodzovsky@amd.com> writes: > Currently calling wait_event_killable as part of exiting process > will stall forever since SIGKILL generation is suppresed by PF_EXITING. > > In our partilaur case AMDGPU driver wants to flush all GPU jobs in > flight before shutting down. But if some job hangs the pipe we still want to > be able to kill it and avoid a process in D state. This makes me profoundly uncomfotable. You are changing the linux semantics of what it means for a process to be exiting. Functionally this may require all kinds of changes to when we allow processes to stop processing signals. So without a really good thought out explanation that takes into account all of the issues involved in process exiting and posix conformance. Nacked-by: "Eric W. Biederman" <ebiederm@xmission.com> Eric > Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com> > --- > kernel/signal.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/signal.c b/kernel/signal.c > index c6e4c83..c49c706 100644 > --- a/kernel/signal.c > +++ b/kernel/signal.c > @@ -886,10 +886,10 @@ static inline int wants_signal(int sig, struct task_struct *p) > { > if (sigismember(&p->blocked, sig)) > return 0; > - if (p->flags & PF_EXITING) > - return 0; > if (sig == SIGKILL) > return 1; > + if (p->flags & PF_EXITING) > + return 0; > if (task_is_stopped_or_traced(p)) > return 0; > return task_curr(p) || !signal_pending(p);
WARNING: multiple messages have this Message-ID (diff)
From: ebiederm@xmission.com (Eric W. Biederman) To: Andrey Grodzovsky <andrey.grodzovsky@amd.com> Cc: linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, Alexander.Deucher@amd.com, Christian.Koenig@amd.com, David.Panariti@amd.com, oleg@redhat.com, akpm@linux-foundation.org Subject: Re: [PATCH 1/3] signals: Allow generation of SIGKILL to exiting task. Date: Tue, 24 Apr 2018 11:10:42 -0500 [thread overview] Message-ID: <87a7tsd1q5.fsf@xmission.com> (raw) In-Reply-To: <1524583836-12130-2-git-send-email-andrey.grodzovsky@amd.com> (Andrey Grodzovsky's message of "Tue, 24 Apr 2018 11:30:34 -0400") Andrey Grodzovsky <andrey.grodzovsky@amd.com> writes: > Currently calling wait_event_killable as part of exiting process > will stall forever since SIGKILL generation is suppresed by PF_EXITING. > > In our partilaur case AMDGPU driver wants to flush all GPU jobs in > flight before shutting down. But if some job hangs the pipe we still want to > be able to kill it and avoid a process in D state. This makes me profoundly uncomfotable. You are changing the linux semantics of what it means for a process to be exiting. Functionally this may require all kinds of changes to when we allow processes to stop processing signals. So without a really good thought out explanation that takes into account all of the issues involved in process exiting and posix conformance. Nacked-by: "Eric W. Biederman" <ebiederm@xmission.com> Eric > Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com> > --- > kernel/signal.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/signal.c b/kernel/signal.c > index c6e4c83..c49c706 100644 > --- a/kernel/signal.c > +++ b/kernel/signal.c > @@ -886,10 +886,10 @@ static inline int wants_signal(int sig, struct task_struct *p) > { > if (sigismember(&p->blocked, sig)) > return 0; > - if (p->flags & PF_EXITING) > - return 0; > if (sig == SIGKILL) > return 1; > + if (p->flags & PF_EXITING) > + return 0; > if (task_is_stopped_or_traced(p)) > return 0; > return task_curr(p) || !signal_pending(p);
next prev parent reply other threads:[~2018-04-24 16:12 UTC|newest] Thread overview: 122+ messages / expand[flat|nested] mbox.gz Atom feed top 2018-04-24 15:30 Avoid uninterruptible sleep during process exit Andrey Grodzovsky 2018-04-24 15:30 ` Andrey Grodzovsky 2018-04-24 15:30 ` [PATCH 1/3] signals: Allow generation of SIGKILL to exiting task Andrey Grodzovsky 2018-04-24 15:30 ` Andrey Grodzovsky 2018-04-24 16:10 ` Eric W. Biederman [this message] 2018-04-24 16:10 ` Eric W. Biederman 2018-04-24 16:42 ` Eric W. Biederman 2018-04-24 16:42 ` Eric W. Biederman 2018-04-24 16:51 ` Andrey Grodzovsky 2018-04-24 16:51 ` Andrey Grodzovsky 2018-04-24 17:29 ` Eric W. Biederman 2018-04-25 13:13 ` Oleg Nesterov 2018-04-24 15:30 ` [PATCH 2/3] drm/scheduler: Don't call wait_event_killable for signaled process Andrey Grodzovsky 2018-04-24 15:30 ` Andrey Grodzovsky 2018-04-24 15:46 ` Michel Dänzer 2018-04-24 15:51 ` Andrey Grodzovsky 2018-04-24 15:51 ` Andrey Grodzovsky 2018-04-24 15:52 ` Andrey Grodzovsky 2018-04-24 15:52 ` Andrey Grodzovsky 2018-04-24 19:44 ` Daniel Vetter 2018-04-24 19:44 ` Daniel Vetter 2018-04-24 21:00 ` Eric W. Biederman 2018-04-24 21:02 ` Andrey Grodzovsky 2018-04-24 21:02 ` Andrey Grodzovsky 2018-04-24 21:21 ` Eric W. Biederman 2018-04-24 21:37 ` Andrey Grodzovsky 2018-04-24 21:37 ` Andrey Grodzovsky 2018-04-24 22:11 ` Eric W. Biederman 2018-04-25 7:14 ` Daniel Vetter 2018-04-25 13:08 ` Andrey Grodzovsky 2018-04-25 13:08 ` Andrey Grodzovsky 2018-04-25 15:29 ` Eric W. Biederman 2018-04-25 16:13 ` Andrey Grodzovsky 2018-04-25 16:31 ` Eric W. Biederman 2018-04-24 21:40 ` Daniel Vetter 2018-04-24 21:40 ` Daniel Vetter 2018-04-25 13:22 ` Oleg Nesterov 2018-04-25 13:36 ` Daniel Vetter 2018-04-25 14:18 ` Oleg Nesterov 2018-04-25 14:18 ` Oleg Nesterov 2018-04-25 13:43 ` Andrey Grodzovsky 2018-04-25 13:43 ` Andrey Grodzovsky 2018-04-24 16:23 ` Eric W. Biederman 2018-04-24 16:23 ` Eric W. Biederman 2018-04-24 16:43 ` Andrey Grodzovsky 2018-04-24 16:43 ` Andrey Grodzovsky 2018-04-24 17:12 ` Eric W. Biederman 2018-04-25 13:55 ` Oleg Nesterov 2018-04-25 14:21 ` Andrey Grodzovsky 2018-04-25 14:21 ` Andrey Grodzovsky 2018-04-25 17:17 ` Oleg Nesterov 2018-04-25 18:40 ` Andrey Grodzovsky 2018-04-25 18:40 ` Andrey Grodzovsky 2018-04-26 0:01 ` Eric W. Biederman 2018-04-26 12:34 ` Andrey Grodzovsky 2018-04-26 12:34 ` Andrey Grodzovsky 2018-04-26 12:52 ` Andrey Grodzovsky 2018-04-26 12:52 ` Andrey Grodzovsky 2018-04-26 15:57 ` Eric W. Biederman 2018-04-26 20:43 ` Andrey Grodzovsky 2018-04-26 20:43 ` Andrey Grodzovsky 2018-04-30 12:08 ` Christian König 2018-04-30 12:08 ` Christian König 2018-04-30 14:32 ` Andrey Grodzovsky 2018-04-30 14:32 ` Andrey Grodzovsky 2018-04-30 15:25 ` Christian König 2018-04-30 15:25 ` Christian König 2018-04-30 16:00 ` Oleg Nesterov 2018-04-30 16:10 ` Andrey Grodzovsky 2018-04-30 16:10 ` Andrey Grodzovsky 2018-04-30 18:29 ` Christian König 2018-04-30 18:29 ` Christian König 2018-04-30 19:28 ` Andrey Grodzovsky 2018-04-30 19:28 ` Andrey Grodzovsky 2018-05-02 11:48 ` Christian König 2018-05-02 11:48 ` Christian König 2018-05-17 11:18 ` Andrey Grodzovsky 2018-05-17 14:48 ` Michel Dänzer 2018-05-17 15:33 ` Andrey Grodzovsky 2018-05-17 15:52 ` Michel Dänzer 2018-05-17 19:05 ` Andrey Grodzovsky 2018-05-18 8:46 ` Michel Dänzer 2018-05-18 9:42 ` Christian König 2018-05-18 14:44 ` Michel Dänzer 2018-05-18 14:50 ` Christian König 2018-05-18 15:02 ` Andrey Grodzovsky 2018-05-22 12:58 ` Christian König 2018-05-22 15:49 ` Andrey Grodzovsky 2018-05-22 16:09 ` Michel Dänzer 2018-05-22 16:30 ` Andrey Grodzovsky 2018-05-22 16:33 ` Michel Dänzer 2018-05-22 16:37 ` Andrey Grodzovsky 2018-05-01 14:35 ` Oleg Nesterov 2018-05-23 15:08 ` Andrey Grodzovsky 2018-05-23 15:08 ` Andrey Grodzovsky 2018-04-30 15:29 ` Oleg Nesterov 2018-04-30 16:25 ` Eric W. Biederman 2018-04-30 17:18 ` Andrey Grodzovsky 2018-04-30 17:18 ` Andrey Grodzovsky 2018-04-25 13:05 ` Oleg Nesterov 2018-04-24 15:30 ` [PATCH 3/3] drm/amdgpu: Switch to interrupted wait to recover from ring hang Andrey Grodzovsky 2018-04-24 15:30 ` Andrey Grodzovsky 2018-04-24 15:52 ` Panariti, David 2018-04-24 15:52 ` Panariti, David 2018-04-24 15:58 ` Andrey Grodzovsky 2018-04-24 15:58 ` Andrey Grodzovsky 2018-04-24 16:20 ` Panariti, David 2018-04-24 16:20 ` Panariti, David 2018-04-24 16:30 ` Eric W. Biederman 2018-04-24 16:30 ` Eric W. Biederman 2018-04-25 17:17 ` Andrey Grodzovsky 2018-04-25 17:17 ` Andrey Grodzovsky 2018-04-25 20:55 ` Eric W. Biederman 2018-04-25 20:55 ` Eric W. Biederman 2018-04-26 12:28 ` Andrey Grodzovsky 2018-04-26 12:28 ` Andrey Grodzovsky 2018-04-24 16:14 ` Eric W. Biederman 2018-04-24 16:14 ` Eric W. Biederman 2018-04-24 16:38 ` Andrey Grodzovsky 2018-04-24 16:38 ` Andrey Grodzovsky 2018-04-30 11:34 ` Christian König 2018-04-30 11:34 ` Christian König
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=87a7tsd1q5.fsf@xmission.com \ --to=ebiederm@xmission.com \ --cc=Alexander.Deucher@amd.com \ --cc=Christian.Koenig@amd.com \ --cc=David.Panariti@amd.com \ --cc=akpm@linux-foundation.org \ --cc=amd-gfx@lists.freedesktop.org \ --cc=andrey.grodzovsky@amd.com \ --cc=linux-kernel@vger.kernel.org \ --cc=oleg@redhat.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.