From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH v2] kvm: x86: mmu: Add cast to negated bitmasks in
 update_permission_bitmask()
Date: Mon, 25 Jun 2018 19:01:42 +0200
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Cc: Matthias Kaehlcke <mka@chromium.org>, rkrcmar@redhat.com,
        Thomas Gleixner <tglx@linutronix.de>, hpa@zytor.com,
        x86@kernel.org, kvm@vger.kernel.org,
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To: Nick Desaulniers <ndesaulniers@google.com>
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On 25/06/2018 18:47, Nick Desaulniers wrote:
> Here's an actual bug this warning caught applied to drivers/input/:
> 
> dae1a432ab1f ("Input: mousedev - fix implicit conversion warning"):
> https://patchwork.kernel.org/patch/9753771/
> 

How does the warning catch a bug there?  While I do prefer the code
after the patch, wouldn't everything work just fine with "signed char
ps2[6]".

So it seems to me in that case (unlike KVM) the warning caught some ugly
code, but not a bug.  (In fact if there was a bug, it should have been
mentioned in the commit message, but it wasn't).

Paolo