Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752812Ab2KSBGv (ORCPT ); Sun, 18 Nov 2012 20:06:51 -0500 Received: from cantor2.suse.de ([195.135.220.15]:49209 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752722Ab2KSBGu (ORCPT ); Sun, 18 Nov 2012 20:06:50 -0500 Date: Mon, 19 Nov 2012 12:06:32 +1100 From: NeilBrown To: Dan Williams Cc: Bartlomiej Zolnierkiewicz , Alan Cox , linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, Vinod Koul , Tomasz Figa , Kyungmin Park Subject: Re: [PATCH] raid5: panic() on dma_wait_for_async_tx() error Message-ID: <20121119120632.1c97e306@notabene.brown> In-Reply-To: <201211081220.55281.b.zolnierkie@samsung.com> References: <201211081106.29980.b.zolnierkie@samsung.com> <20121108111526.40c705a0@pyramind.ukuu.org.uk> <201211081220.55281.b.zolnierkie@samsung.com> X-Mailer: Claws Mail 3.8.1 (GTK+ 2.24.10; x86_64-suse-linux-gnu) Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/CGEjut4vitKwCKGwiQXBBsp"; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3876 Lines: 100 --Sig_/CGEjut4vitKwCKGwiQXBBsp Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Hi Dan, could you comment on this please? Would it make sense to arrange for erro= rs to propagate up? Or should we arrange to do a software-fallback in the dma engine is a problem? What sort of things can cause error here anyway? Thanks, NeilBrown On Thu, 08 Nov 2012 12:20:55 +0100 Bartlomiej Zolnierkiewicz wrote: > On Thursday 08 November 2012 12:15:26 Alan Cox wrote: > > On Thu, 08 Nov 2012 11:06:29 +0100 > > Bartlomiej Zolnierkiewicz wrote: > >=20 > > > From: Bartlomiej Zolnierkiewicz > > > Subject: [PATCH] raid5: panic() on dma_wait_for_async_tx() error > > >=20 > > > There is not much we can do on dma_wait_for_async_tx() error > > > so just panic() for now. > > >=20 > > > Cc: Neil Brown > > > Cc: Vinod Koul > > > Cc: Dan Williams > > > Cc: Tomasz Figa > > > Signed-off-by: Bartlomiej Zolnierkiewicz > > > Signed-off-by: Kyungmin Park > > > --- > > > drivers/md/raid5.c | 4 +++- > > > 1 file changed, 3 insertions(+), 1 deletion(-) > > >=20 > > > Index: b/drivers/md/raid5.c > > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > > --- a/drivers/md/raid5.c 2012-11-07 16:25:19.480876012 +0100 > > > +++ b/drivers/md/raid5.c 2012-11-07 16:27:46.244875992 +0100 > > > @@ -3223,7 +3223,9 @@ static void handle_stripe_expansion(stru > > > /* done submitting copies, wait for them to complete */ > > > if (tx) { > > > async_tx_ack(tx); > > > - dma_wait_for_async_tx(tx); > > > + if (dma_wait_for_async_tx(tx) !=3D DMA_SUCCESS) > > > + panic("%s: DMA error waiting for transaction\n", > > > + __func__); > >=20 > > Thats a really horrible place to panic. >=20 > Still it seems better thing to do than silently ignoring errors > and trying to continue operations with inconsistent data. >=20 > Unfortunately higher-layers don't support error conditions and > fixing them seems to be non-trivial task. >=20 > Best regards, > -- > Bartlomiej Zolnierkiewicz > Samsung Poland R&D Center > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html --Sig_/CGEjut4vitKwCKGwiQXBBsp Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (GNU/Linux) iQIVAwUBUKmGGDnsnt1WYoG5AQKUAhAAkhDfnRaMJKye6ycN7dCrAfc/punNkGhM Lo7GdUr7fBr96YGYVoqW3/v1lTP00kQICPl9LI8soCfIwWyObPrNMmo27KsP1d2F CFgLRs5JCObYtZNxrzm0lH7RRRyQYar03TSPW8HSv+Sz7SA+n0dng1X17XLHZnck quP9bvUTQ/fAo1ZYCjEVVvpis2Gmlk0MDvACM2GQBLUHdOYleyVbmIz9zZJb08Q5 uQA2/YQwDp/WY1zpdZmPy+9yJ0tCO6CATnGmLFNjsOogpPlI0eecZstMobJgRy/K p9+OE2Fb999f4Vb4kUUImC5+36Su3H7vDhoz1nRwmfNI6Ekd4i1L7NdW1w1RgvMh E1SlNePCyXXktkwyNaYyPKUOe43TPw3gKc0GXcKjQDE5autQMnR0DJpewC3GwfBc gV41p4SxqMfGTgHeq607qk97KlohOdAS6w8edl7UuN5FqUzMizBJKWr3tCMyR6nI aS4Yqy7SbuGKPq2rZERrffxZ6ZQMklEWg0YpZjT+++qX1Q/WLsEgjgPU8fUk1E+w zWP3N9Ns9EURA6uIyXTYaEVvOLSxaCMYwxJu7O9as+IQcxhxStIlJoeWzLfpjOos m8QBMVNmNliYvypj4T0oJcWWfQVdvXS7PpsEBwRa7rz3Dczwh0Yu79DvBjWi199M l2h18z1AZpc= =934d -----END PGP SIGNATURE----- --Sig_/CGEjut4vitKwCKGwiQXBBsp-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/