Re: [PATCH for-8.1] accel/tcg: Take mmap_lock in load_atomic16_or_exit

[Alex Bennée]

Richard Henderson <richard.henderson@linaro.org> writes:

> On 7/17/23 11:40, Alex Bennée wrote:
>> Richard Henderson <richard.henderson@linaro.org> writes:
>> 
>>> For user-only, the probe for page writability may race with another
>>> thread's mprotect.  Take the mmap_lock around the operation.  This
>>> is still faster than the start/end_exclusive fallback.
>> Did we have a bug report or replication for this?
>
> See the comment:
>
>> +         * We must take mmap_lock so that the query remains valid until
>> +         * the write is complete -- tests/tcg/multiarch/munmap-pthread.c
>> +         * is an example that can race.

doh...

>
>
> r~


-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro