Re: [PATCH v6 1/2] x86/delay: Fix the wrong asm constraint in `delay_loop()`

[Thomas Gleixner]

On Sun, Apr 03 2022 at 18:57, Thomas Gleixner wrote:
> On Tue, Mar 29 2022 at 17:47, Ammar Faizi wrote:
>> The asm constraint does not reflect that the asm statement can modify
>> the value of @loops. But the asm statement in delay_loop() does modify
>> the @loops.
>>
>> Specifiying the wrong constraint may lead to undefined behavior, it may
>> clobber random stuff (e.g. local variable, important temporary value in
>> regs, etc.). This is especially dangerous when the compiler decides to
>> inline the function and since it doesn't know that the value gets
>> modified, it might decide to use it from a register directly without
>> reloading it.

Ignore me, I misread this part of the explanation.

Thanks,

        tglx