On 2018-05-18 00:11, Dmitry Safonov wrote:
2018-05-17 22:07 GMT+01:00 Andy Lutomirski <luto@xxxxxxxxxx>:
On Thu, May 17, 2018 at 1:51 PM Dmitry Safonov <0x7f454c46@xxxxxxxxx>
wrote:
2018-05-17 21:46 GMT+01:00 Andy Lutomirski <luto@xxxxxxxxxx>:
> On Thu, May 17, 2018 at 1:25 PM Alexey Izbyshev <izbyshev@xxxxxxxxx>
wrote:
>
>> Hello everyone,
>
>> I've discovered the following strange behavior of a 4.15.13-based
kernel
>> (bisected to
>
>
>
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1b028f784e8c341e762c264f70dc0ca1418c8b7a
>> between 4.11-rc2 and -rc3 thanks to Alexander Monakov).
>
>
> It's definitely not intended. Can you confirm that the problem still
> exists in 4.16? I have some vague recollection that this was a known
issue
> that got fixed, and we could plausibly just be missing a backport.
I'm looking into that ATM, the problem like that was fixed with
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ada26481dfe6
Will check what's happening there.
I haven't tried to figure out exactly what code calls which function,
but
it seems like set_personality_64bit() really ought to clear TS_COMPAT.
Ugh, yeah, the same way __set_personality_x32().
Will test it and prepare a patch for that Cc'ing stable.
Thanks, Alexey, Andy!
Thanks, Dmitry, Andy for the quick investigation, and Alexander for the
confirmation!
-Alexey
