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To:     Peter Zijlstra <peterz@infradead.org>, bp@alien8.de,
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From:   Chris Wilson <chris@chris-wilson.co.uk>
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Subject: Re: [PATCH 6/8] i915,uaccess: Fix redundant CLAC
Date:   Thu, 28 Feb 2019 15:10:44 +0000
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Quoting Peter Zijlstra (2019-02-28 14:54:56)
> drivers/gpu/drm/i915/i915_gem_execbuffer.o: warning: objtool: .altinstr_replacement+0x3c: redundant UACCESS disable
> drivers/gpu/drm/i915/i915_gem_execbuffer.o: warning: objtool: .altinstr_replacement+0x66: redundant UACCESS disable
> 
> AKA. you don't need user_access_end() if user_access_begin() fails.

Cool, I had no idea if it was required or not. The closest to
instructions on how to use user_access_begin() is in
arch/x86/include/asm/uaccess.h ... which I guess is earlier in this
series!

> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris