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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sun, 4 Feb 2024 11:45:13 +0000
Message-ID: <CAHk-=wjvt75XFUWxPQQJZE0Wdi8HtSLtqQm2L-ZrqH7=2g3ByQ@mail.gmail.com>
Subject: Re: [PATCH v2 0/3] Handle delay slot for extable lookup
To: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Oleg Nesterov <oleg@redhat.com>, Thomas Bogendoerfer <tsbogend@alpha.franken.de>, 
	Andrew Morton <akpm@linux-foundation.org>, Ben Hutchings <ben@decadent.org.uk>, 
	linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, 
	linux-mips@vger.kernel.org, linux-mm@kvack.org, 
	Xi Ruoyao <xry111@xry111.site>
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On Sun, 4 Feb 2024 at 11:03, Jiaxun Yang <jiaxun.yang@flygoat.com> wrote:
>
> Well this is the tricky part of my assumption.
> In `exception_epc()` `__isa_exception_epc()` stuff is only called if we
> are in delay slot.
> It is impossible for a invalid instruction_pointer to be considered as
> "in delay slot" by hardware.

Ok, I guess I'm convinced this is all safe. Not great, and not exactly
giving me the warm fuzzies, but not buggy.

         Linus