From: Arjan van de Ven <arjanv@redhat.com>
To: "Justin T. Gibbs" <Justin_Gibbs@adaptec.com>
Cc: linux-scsi@vger.kernel.org
Subject: Re: [PATCH] 2.4.X Avoid excessive recursion when setting device offline
Date: Mon, 29 Mar 2004 19:26:48 +0200 [thread overview]
Message-ID: <1080581208.3570.10.camel@laptop.fenrus.com> (raw)
In-Reply-To: <387680000.1080580020@aslan.btc.adaptec.com>
[-- Attachment #1.1: Type: text/plain, Size: 1117 bytes --]
On Mon, 2004-03-29 at 19:07, Justin T. Gibbs wrote:
> How to reproduce: Queue up lots of I/O to a device. Set that device
> offline.
>
> Result: The SCSI mid-layer blows out the kernel stack due to the inherent
> recursion in its request function. The repeating stack trace goes
> something like:
>
> scsi_request_fn
> __scsi_end_request
> scsi_release_command
> scsi_queue_next_request
> scsi_request_fn
> ...
>
> This patch prevents recursive calls through the scsi_request_fn
> for the same queue:
won't this achieve the same ?
diff -urN Linux/drivers/scsi/scsi_lib.c linux/drivers/scsi/scsi_lib.c
--- Linux/drivers/scsi/scsi_lib.c 2002-10-03 16:50:07.000000000
+0200
+++ linux/drivers/scsi/scsi_lib.c 2002-10-03 17:33:20.000000000
+0200
@@ -442,7 +442,7 @@
* This will goose the queue request function at the end, so we
don't
* need to worry about launching another command.
*/
- scsi_release_command(SCpnt);
+ __scsi_release_command(SCpnt);
if( frequeue ) {
request_queue_t *q;
[-- Attachment #1.2: scsi.patch --]
[-- Type: text/x-patch, Size: 480 bytes --]
diff -urN Linux/drivers/scsi/scsi_lib.c linux/drivers/scsi/scsi_lib.c
--- Linux/drivers/scsi/scsi_lib.c 2002-10-03 16:50:07.000000000 +0200
+++ linux/drivers/scsi/scsi_lib.c 2002-10-03 17:33:20.000000000 +0200
@@ -442,7 +442,7 @@
* This will goose the queue request function at the end, so we don't
* need to worry about launching another command.
*/
- scsi_release_command(SCpnt);
+ __scsi_release_command(SCpnt);
if( frequeue ) {
request_queue_t *q;
[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 189 bytes --]
next prev parent reply other threads:[~2004-03-29 17:26 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-03-29 17:07 [PATCH] 2.4.X Avoid excessive recursion when setting device offline Justin T. Gibbs
2004-03-29 17:26 ` Arjan van de Ven [this message]
2004-03-29 17:42 ` Justin T. Gibbs
2004-03-29 17:47 ` James Bottomley
2004-03-29 17:52 ` Justin T. Gibbs
2004-03-30 7:03 ` Jens Axboe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1080581208.3570.10.camel@laptop.fenrus.com \
--to=arjanv@redhat.com \
--cc=Justin_Gibbs@adaptec.com \
--cc=linux-scsi@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.