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Date: Tue, 23 Nov 2010 09:12:40 +0100
From: Hannes Reinecke <hare@suse.de>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] Re: [PATCH] scsi: Implement alloc_req_iov callback
References: <20101122101536.2B09BF90AF@ochil.suse.de>
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: qemu-devel@nongnu.org, nab@linux-iscsi.org, kraxel@redhat.com

On 11/22/2010 10:48 PM, Stefan Hajnoczi wrote:
> On Mon, Nov 22, 2010 at 10:15 AM, Hannes Reinecke <hare@suse.de> wrote:
> Looks good.  If you send out another version of the patchset you might
> like to fix this nitpick:
>=20
>> +    if (!r->io_header.iovec_count) {
>> +        if (r->buflen !=3D r->req.cmd.xfer) {
>> +            if (r->buf !=3D NULL)
>> +                qemu_free(r->buf);
>=20
> qemu_free(NULL) is a nop so it's safe to drop the if (r->buf !=3D NULL)
> check and just use qemu_free(r->buf) unconditionally.  That's nice
> since it also fixes the if statement without curly braces.
>=20
Really?

qemu-malloc.c has:

void qemu_free(void *ptr)
{
    trace_qemu_free(ptr);
    free(ptr);
}


and 'free' doesn't normally do an error checking on the argument.
Am I missing something?

Cheers,

Hannes
--=20
Dr. Hannes Reinecke		      zSeries & Storage
hare@suse.de			      +49 911 74053 688
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg
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