Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757587AbYGJX7U (ORCPT ); Thu, 10 Jul 2008 19:59:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755402AbYGJX7I (ORCPT ); Thu, 10 Jul 2008 19:59:08 -0400 Received: from mx1.redhat.com ([66.187.233.31]:51706 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752131AbYGJX7F (ORCPT ); Thu, 10 Jul 2008 19:59:05 -0400 Date: Thu, 10 Jul 2008 19:57:41 -0400 (EDT) From: Mikulas Patocka To: Julian Calaby cc: sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, Jens Axboe Subject: Re: [SUGGESTION]: drop virtual merge accounting in I/O requests In-Reply-To: <646765f40807101559q51fbfc50x8e3466e5f202e0c8@mail.gmail.com> Message-ID: References: <646765f40807101559q51fbfc50x8e3466e5f202e0c8@mail.gmail.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1245 Lines: 38 On Fri, 11 Jul 2008, Julian Calaby wrote: > On Fri, Jul 11, 2008 at 07:56, Mikulas Patocka wrote: >> Hi >> >> I'm getting crashes with InitIO A100u2w controller on Sparc64 (I had to fix >> the endianity issues in the driver, but that's unrelated). >> >> When I examined the crashes, it turned out that SCSI layer passed requests >> with too many segments. The controller has at most 32 SG entries per >> request. It sets shost->sg_tablesize to 32, but despite this, larger >> requests were submitted to it --- this resulted in overwriting random memory >> and crashes. > > [snip] > > Should this have been CC'd to linux-scsi too? This sounds like it > could be a bug at their end. > > Thanks, > > -- > Julian Calaby This is not a bug in scsi layer, those "nr_hw_segments" miscalculations are hapenning in block/blk-merge.c and they can show up with any block device driver that has small number of SG entries. But I can CC it there, just for their information. Mikulas -- 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/