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Subject: Re: BUG: unable to handle kernel paging request from pty_write [was:
 Linux 4.4.2]
To: Jiri Kosina <jikos@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
References: <20160217203730.GA14820@kroah.com> <56CED373.9060603@suse.cz>
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Cc: Peter Hurley <peter@hurleysoftware.com>,
        Greg KH <gregkh@linuxfoundation.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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From: Jiri Slaby <jslaby@suse.cz>
Message-ID: <56D00D5D.8020709@suse.cz>
Date: Fri, 26 Feb 2016 09:31:25 +0100
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On 02/25/2016, 11:00 PM, Jiri Kosina wrote:
>> If it was one of the calls _in_ try_to_wake_up() that called to insane 
>> code, I would have expected to see try_to_wake_up on the stack.
> 
> try_to_wake_up() is very likely to be inlined into wake_up_process(), and 
> therefore in such cases will never be on the stack as a return address; 
> it'll always be wake_up_process().

Actually it is not inlined, see core.s at:
http://labs.suse.cz/jslaby/bug-968218/

thanks,
-- 
js
suse labs