Message-ID: <79a85431-a505-795d-1e72-76628df987af@suse.com>
Date:   Fri, 19 Nov 2021 09:24:16 +0100
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Subject: Re: [PATCH] xen: detect uninitialized xenbus in xenbus_init
Content-Language: en-US
To:     Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Stefano Stabellini <sstabellini@kernel.org>
Cc:     xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org,
        Stefano Stabellini <stefano.stabellini@xilinx.com>,
        stable@vger.kernel.org, Juergen Gross <jgross@suse.com>
References: <20211117021145.3105042-1-sstabellini@kernel.org>
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From:   Jan Beulich <jbeulich@suse.com>
In-Reply-To: <fdfe4ba4-8f5f-47a2-98df-3dfdb50d8f6f@oracle.com>
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On 18.11.2021 23:24, Boris Ostrovsky wrote:
> On 11/18/21 4:00 PM, Stefano Stabellini wrote:
>>
>>          /*
>>           * Avoid truncation on 32-bit.
>>           * TODO: handle addresses >= 4G
>>           */
>>          if ( v >= ~0UL ) {
>>              err = -EINVAL;
>>              goto out_error;
>>          }
> 
> 
> Since this is only relevant to 32-bit kernels then "#if BITS_PER_LONG == 32".

Plus then > instead of >= (thus also making the comment actually decribe
the code) and ULONG_MAX instead of ~0UL, I would say.

Jan