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

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Date:   Fri, 19 Aug 2016 16:06:56 +0300
From:   Andrey Ryabinin <aryabinin@...tuozzo.com>
To:     Richard Weinberger <richard@....at>,
        Dmitry Vyukov <dvyukov@...gle.com>
CC:     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 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.

> Thanks,
> //richard
>