From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Date: Fri, 13 Jan 2017 03:53:07 +0000
Subject: Re: [PATCH] mm/page_alloc: Wait for oom_lock before retrying.
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To: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Petr Mladek <pmladek@suse.com>, Sergey Senozhatsky <sergey.senozhatsky@gmail.com>, Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>, mhocko@suse.com, linux-mm@kvack.org, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Jiri Slaby <jslaby@suse.cz>, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org

On (01/13/17 11:52), Sergey Senozhatsky wrote:
[..]
> and we really don't want to cond_resched() when we are in panic.
> that's why console_flush_on_panic() sets it to zero explicitly.
> 
> console_trylock() checks oops_in_progress, so re-taking the semaphore
> when we are in
> 
> 	panic()
> 	 console_flush_on_panic()
>           console_unlock()
>            console_trylock()
> 
> should be OK. as well as doing get_console_conditional_schedule() somewhere
> in console driver code.

d'oh... no, this is false. console_flush_on_panic() is called after we
bust_spinlocks(0), BUT with local IRQs disabled. so console_trylock()
would still set console_may_schedule to 0.

	-ss