From: Tejun Heo <tj@kernel.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
Petr Mladek <pmladek@suse.com>,
linux-kernel@vger.kernel.org, kernel-team@fb.com,
Linus Torvalds <torvalds@linux-foundation.org>,
Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 2/2] Subject: printk: Don't trap random context in infinite log_buf flush
Date: Wed, 8 Nov 2017 08:28:13 -0800 [thread overview]
Message-ID: <20171108162813.GA983427@devbig577.frc2.facebook.com> (raw)
In-Reply-To: <20171108112229.200858cb@gandalf.local.home>
Hello, Steven.
On Wed, Nov 08, 2017 at 11:22:29AM -0500, Steven Rostedt wrote:
> > Oh, I was talking about tweaking the repro, but I'm not sure the above
> > would change anything.
>
> No, it would change an awful lot.
>
> It would cause two printers to access the consoles at the same time,
> which would lead to unpredictable behavior.
Sure, I'll give it a shot later but in the repro there literally is no
context which is safe, so I kinda have a difficult time imagining how
that will make things materially better. Neither of the producers can
get scheduled out no matter they switch back and forth between them or
not, so rcu stalls seem rather unavoidable without introducing an
independent context.
Thanks.
--
tejun
next prev parent reply other threads:[~2017-11-08 16:28 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-02 13:51 [PATCH 1/2] printk: Relocate wake_klogd check close to the end of console_unlock() Tejun Heo
2017-11-02 13:52 ` [PATCH 2/2] Subject: printk: Don't trap random context in infinite log_buf flush Tejun Heo
2017-11-02 14:51 ` [PATCH TRIVIAL UPDATE 2/2] " Tejun Heo
2017-11-04 4:24 ` [PATCH 2/2] Subject: " Sergey Senozhatsky
2017-11-07 0:22 ` Tejun Heo
2017-11-07 2:04 ` Sergey Senozhatsky
2017-11-07 13:23 ` Tejun Heo
2017-11-08 5:29 ` Sergey Senozhatsky
2017-11-08 14:33 ` Tejun Heo
2017-11-08 16:22 ` Steven Rostedt
2017-11-08 16:28 ` Tejun Heo [this message]
2017-11-08 16:20 ` Steven Rostedt
2017-11-07 4:40 ` [PATCH 1/2] printk: Relocate wake_klogd check close to the end of console_unlock() Sergey Senozhatsky
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