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Date: Thu, 6 Sep 2018 22:25:47 +0200
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH v2 1/6] Fix "x86/alternatives: Lockdep-enforce text_mutex
 in text_poke*()"
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To: Nadav Amit <namit@vmware.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@redhat.com>, X86 ML <x86@kernel.org>, Arnd Bergmann <arnd@arndb.de>, linux-arch <linux-arch@vger.kernel.org>, Dave Hansen <dave.hansen@linux.intel.com>, Jiri Kosina <jkosina@suse.cz>, Andy Lutomirski <luto@kernel.org>, Kees Cook <keescook@chromium.org>, Dave Hansen <dave.hansen@intel.com>
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On Thu, Sep 06, 2018 at 07:58:40PM +0000, Nadav Amit wrote:
> > With that CR3 trickery, we can rid ourselves of the text_mutex
> > requirement, since concurrent text_poke is 'safe'. That would clean up
> > the kgdb code quite a bit.
> 
> I don’t know. I’m somewhat worried with multiple mechanisms potentially
> changing the same code at the same time - and maybe ending up with some
> mess.

kgdb only pokes INT3, that should be pretty safe.