Date:   Sun, 22 Jan 2023 22:10:04 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     Tom Rix <trix@redhat.com>, tim@cyberelk.net, nathan@kernel.org,
        ndesaulniers@google.com, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, llvm@lists.linux.dev
Subject: Re: [PATCH v2] paride/pcd: return earlier when an error happens in
 pcd_atapi()
Message-ID: <Y820PCtcJv12fJpI@ZenIV>
References: <20230122154901.505142-1-trix@redhat.com>
 <1a501bc9-7058-6c47-0ebf-44459bc0e730@kernel.dk>
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On Sun, Jan 22, 2023 at 01:49:00PM -0700, Jens Axboe wrote:
> On 1/22/23 8:49 AM, Tom Rix wrote:
> > clang static analysis reports
> > drivers/block/paride/pcd.c:856:36: warning: The left operand of '&'
> >   is a garbage value [core.UndefinedBinaryOperatorResult]
> >   tocentry->cdte_ctrl = buffer[5] & 0xf;
> >                         ~~~~~~~~~ ^
> 
> Has this one been compiled? I'm guessing not tested...
> 
> In any case, this code is going away hopefully shortly, so let's not
> bother with changes like this.

	Look at the callers - the value left in entry is discarded if
->audio_ioctl(..., CDROMREADTOCENTRY, &entry) returns non-zero.  Sure,
it's a nasal daemon territory, but realistically it's not going to be
caught by testing.