From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <JBeulich@novell.com>
Subject: Re: [PATCH] Re: Another blktap2-ish shutdown crash
Date: Mon, 07 Jun 2010 14:43:27 +0100
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To: Daniel Stodden <daniel.stodden@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
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>>> On 07.06.10 at 13:12, Daniel Stodden <daniel.stodden@citrix.com> =
wrote:
> On Mon, 2010-06-07 at 03:29 -0400, Jan Beulich wrote:
>> >>> On 03.06.10 at 03:50, Daniel Stodden <daniel.stodden@citrix.com> =
wrote:
>>=20
>> Why would you want blk_start_request() only after the blk_fs_request()
>> check, but not after the blk_barrier_rq() one?
>=20
> Huh? But cases did get the blk_start_request call (?!)

I have to admit that I don't understand your response at all.

Assuming that you think my original question was rubbish, this is
the original (before your patch) code I look at

	while ((req =3D blk_peek_request(rq)) !=3D NULL) {
		if (!blk_fs_request(req)) {
			blk_end_request(req, -EIO, 0);
			continue;
		}

		if (blk_barrier_rq(req)) {
			blk_end_request(req, -EIO, 0);
			continue;
		}
...
		blk_start_request(req);
...

Your patch inserts a call to blk_start_request() into the
first if clause's body, and I was asking why the second
one's wouldn't also need such a call.

Sorry if I'm being dense - I'll appreciate any enlightenment.

Jan