Messages in this thread | | | Date | Thu, 6 Sep 2018 21:40:03 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH v2 1/6] Fix "x86/alternatives: Lockdep-enforce text_mutex in text_poke*()" |
| |
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().
| |