linux-kernel - Re: [PATCH] UML: don't discard .text.exit section

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Date:   Fri, 19 Aug 2016 08:24:05 -0700
From:   Dmitry Vyukov <dvyukov@...gle.com>
To:     Andrey Ryabinin <aryabinin@...tuozzo.com>
Cc:     Richard Weinberger <richard@....at>, Jeff Dike <jdike@...toit.com>,
        user-mode-linux-devel <user-mode-linux-devel@...ts.sourceforge.net>,
        LKML <linux-kernel@...r.kernel.org>,
        Stefan Traby <stefan@...lo-penguin.com>,
        stable <stable@...r.kernel.org>
Subject: Re: [PATCH] UML: don't discard .text.exit section

On Fri, Aug 19, 2016 at 6:06 AM, Andrey Ryabinin
<aryabinin@...tuozzo.com> wrote:
>
>
> On 08/19/2016 02:16 PM, Richard Weinberger wrote:
>> On 19.08.2016 12:48, Andrey Ryabinin wrote:
>>> On 08/19/2016 03:14 AM, Dmitry Vyukov wrote:
>>>> On Thu, Aug 18, 2016 at 3:08 AM, Andrey Ryabinin
>>>> <aryabinin@...tuozzo.com> wrote:
>>>>>
>>>>>>
>>>>>> Sorry for delays, I am travelling.
>>>>>> Do we need ".fini_array" section? It's also destructors that we don't
>>>>>> run. Or does UML use them? Does discarding ".fini_array" help?
>>>>>>
>>>>>
>>>>> libc has desctructors and use them for whatever purpose it needs.
>>>>
>>>>
>>>> Does UML actually gracefully exit running global destructors? That
>>>> would also require gracefully shutting down all threads/cpus. Doesn't
>>>> it just _exit (or syscall(SYS_exit_group))?
>>>>
>>>
>>> Sigh, I dunno, I didn't look that far. My intention was to fix build and keep old behavior unaffected.
>>> If you want to wipe destructors, and think that this is ok, go ahead.
>>
>> UML exits like any regular C program does.
>> The main() function is in arch/um/os-Linux/main.c, when the kernel terminates,
>> hence linux_main() returns back to main() it just returns the exit code.
>> At this point libc's destructors will run, right?
>>
> Sounds right to me.



If it exits then

Acked-by: Dmitry Vyukov <dvyukov@...gle.com>

Thanks for taking care of it.