Subject: Re: SCSI over USB showstopper bug?
From: Arjan van de Ven <arjan@infradead.org>
To: Joerg Schilling <Joerg.Schilling@fokus.fraunhofer.de>
Cc: schilling@fokus.fraunhofer.de, linux-kernel@vger.kernel.org
In-Reply-To: <4547c966.8oyAB/pzCZ7bGUza%Joerg.Schilling@fokus.fraunhofer.de>
References: <4547c966.8oyAB/pzCZ7bGUza%Joerg.Schilling@fokus.fraunhofer.de>
Content-Type: text/plain
Organization: Intel International BV
Date: Tue, 31 Oct 2006 23:18:10 +0100
Message-Id: <1162333090.3044.53.camel@laptopd505.fenrus.org>
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1015
Lines: 29

On Tue, 2006-10-31 at 23:08 +0100, Joerg Schilling wrote:
> Hi,
> 
> it looks as if SG_GET_RESERVED_SIZE & SG_SET_RESERVED_SIZE
> are not in interaction with the underlying SCSI transport.
> 
> Programs like readcd and cdda2wav that try to get very large SCSI
> transfer buffers get a confirmation for nearly any SCSI transfer size 
> but later when readcd/cdda2wav try to transfer data with an
> actual SCSI command, they fail with ENOMEM.
> 
> Correct fix: let sg.c make a callback to the underlying SCSI transport
> 		and let it get a confirmation tfor the buffer size.
> 
> Quick and dirty fix: reduce the maximum allowed DMA size to the smallest
> 		max DMA size of all SCSI transports.

real good fix:

use SG_IO on the device directly that checks this already


-
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/