Re: [PATCH v2 1/6] Fix "x86/alternatives: Lockdep-enforce text_mutex in text_poke*()"

[Nadav Amit]

at 12:40 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:

> On Sun, Sep 02, 2018 at 10:32:19AM -0700, Nadav Amit wrote:
>> text_mutex is expected to be held before text_poke() is called, but we
>> cannot add a lockdep assertion since kgdb does not take it, and instead
>> *supposedly* ensures the lock is not taken and will not be acquired by
>> any other core while text_poke() is running.
>> 
>> The reason for the "supposedly" comment is that it is not entirely clear
>> that this would be the case if gdb_do_roundup is zero.
> 
> Argh, that's pretty shit code...
> 
> Not only is that text_mutex abuse ugly, so too is the fixmap usage from
> IRQ context. I suppose this really does require your alternative mm
> patches for text_poke().

Right, I forgot about thatâ