Message-ID: <fdfe4ba4-8f5f-47a2-98df-3dfdb50d8f6f@oracle.com>
Date:   Thu, 18 Nov 2021 17:24:46 -0500
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Subject: Re: [PATCH] xen: detect uninitialized xenbus in xenbus_init
Content-Language: en-US
To:     Stefano Stabellini <sstabellini@kernel.org>,
        Juergen Gross <jgross@suse.com>
Cc:     Jan Beulich <jbeulich@suse.com>, xen-devel@lists.xenproject.org,
        linux-kernel@vger.kernel.org,
        Stefano Stabellini <stefano.stabellini@xilinx.com>,
        stable@vger.kernel.org
References: <20211117021145.3105042-1-sstabellini@kernel.org>
 <2592121c-ed62-c346-5aeb-37adb6bb1982@suse.com>
 <alpine.DEB.2.22.394.2111171823160.1412361@ubuntu-linux-20-04-desktop>
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 <9453672e-56ea-71cd-cdd2-b4aaafb8db56@suse.com>
 <b0cd6af9-66c4-3a73-734a-3a51d052fac2@suse.com>
 <alpine.DEB.2.22.394.2111181226460.1412361@ubuntu-linux-20-04-desktop>
From:   Boris Ostrovsky <boris.ostrovsky@oracle.com>
In-Reply-To: <alpine.DEB.2.22.394.2111181226460.1412361@ubuntu-linux-20-04-desktop>
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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".


-boris