Re: [PATCH 1/1] get_nr_restart_syscall() should return __NR_ia32_restart_syscall if __USER32_CS

Andy Lutomirski
2017-03-29T17:00:00Z

On Wed, Mar 29, 2017 at 8:05 AM, Oleg Nesterov <oleg@redhat.com> wrote:
> On 03/28, Oleg Nesterov wrote:
>>
>> On 03/28, Andy Lutomirski wrote:
>> >
>> > How about we store the syscall arch to be restored in task_struct
>> > along with restart_block?
>>
>> Yes, perhaps we will have to finally do this. Not really nice too.
>
> OK, how about the hack below?
>
> I do not want to a new member into task_struct/restart_block, so the
> patch below adds a sticky TS_COMPAT bit which logically is a member
> of "struct restart_block".

Okay, but I'd much rather we just added a helper that's called in the
few places that actually write to restart_block.

Or we just add the new syscall nr and see what breaks. The answer
could well be nothing at all.

--Andy