Re: [PATCH 08/12] x86/dumpstack: Pin the target stack in save_stack_trace_tsk()

From: Andy Lutomirski
Date: Thu Sep 15 2016 - 14:05:20 EST

On Wed, Sep 14, 2016 at 11:35 AM, Josh Poimboeuf <jpoimboe@xxxxxxxxxx> wrote:
> On Wed, Sep 14, 2016 at 11:22:00AM -0700, Andy Lutomirski wrote:
>> On Wed, Sep 14, 2016 at 7:55 AM, Josh Poimboeuf <jpoimboe@xxxxxxxxxx> wrote:
>> > On Tue, Sep 13, 2016 at 02:29:28PM -0700, Andy Lutomirski wrote:
>> >> This will prevent a crash if the target task dies before or while
>> >> dumping its stack once we start freeing task stacks early.
>> >>
>> >> Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
>> >
>> > Do we need a similar patch for show_stack()?
>> Probably. Shouldn't it go in show_stack_log_lvl() instead, though?
> Yeah, that would probably be better.

This code is a colossal mess. I really hope that, some day, we can
clarify which entry points are used only in dumpstack*.c and which are
used elsewhere. Creating an arch/x86/kernel/dumpstack.h or just
merging the three files and removing all the intermediate crap from
the headers could help a lot.