From: Dinakar Guniguntala <dino@in.ibm.com>
To: linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@elte.hu>, David Singleton <dsingleton@mvista.com>
Subject: [PATCH] Fix timeout in robust path
Date: Thu, 8 Dec 2005 01:04:29 +0530 [thread overview]
Message-ID: <20051207193429.GD4897@in.ibm.com> (raw)
[-- Attachment #1: Type: text/plain, Size: 1654 bytes --]
Hi Ingo,
I hit the following BUG when exercising the robust futex path
testpi-1/4920[CPU#0]: BUG in FREE_WAITER at kernel/rt.c:1368
[<c011f180>] __WARN_ON+0x60/0x80 (8)
[<c03f6581>] __down_mutex+0x601/0x844 (48)
[<c013813a>] pi_setprio+0xa1/0x632 (104)
[<c0127386>] lock_timer_base+0x19/0x33 (8)
[<c03f884d>] _spin_lock_irqsave+0x1d/0x46 (12)
[<c0127386>] lock_timer_base+0x19/0x33 (8)
[<c0127386>] lock_timer_base+0x19/0x33 (16)
[<c01273d8>] __mod_timer+0x38/0xdf (16)
[<c013fb9b>] sub_preempt_count+0x1a/0x1e (12)
[<c03f81e1>] __down_interruptible+0x922/0xaf7 (20)
[<c01411f5>] futex_wait_robust+0x14c/0x216 (16)
[<c01394e8>] process_timeout+0x0/0x9 (48)
[<c01411f5>] futex_wait_robust+0x14c/0x216 (64)
[<c013d042>] down_futex+0x7d/0xe2 (12)
[<c01411f5>] futex_wait_robust+0x14c/0x216 (12)
[<c013d066>] down_futex+0xa1/0xe2 (8)
[<c01411f5>] futex_wait_robust+0x14c/0x216 (12)
[<c01411f5>] futex_wait_robust+0x14c/0x216 (24)
[<c01419de>] do_futex+0x92/0xf8 (72)
[<c0141b3c>] sys_futex+0xf8/0x104 (40)
[<c0103017>] sysenter_past_esp+0x54/0x75 (60)
---------------------------
| preempt count: 00000001 ]
| 1-level deep critical section nesting:
----------------------------------------
.. [<c013fb00>] .... add_preempt_count+0x1a/0x1e
.....[<00000000>] .. ( <= stext+0x3feffd68/0x8)
------------------------------
| showing all locks held by: | (testpi-1/4920 [f6326120, 59]):
------------------------------
When calling futex_wait_robust, we need to ensure that the timeout
is reset to zero, incase userspace timeout is NULL.
Please consider applying
-Dinakar
Signed-off-by: Dinakar Guniguntala <dino@in.ibm.com>
[-- Attachment #2: rt22-timeout.patch --]
[-- Type: text/plain, Size: 465 bytes --]
Index: linux-2.6.14/kernel/futex.c
===================================================================
--- linux-2.6.14.orig/kernel/futex.c 2005-12-08 00:31:29.000000000 +0530
+++ linux-2.6.14/kernel/futex.c 2005-12-08 00:33:01.000000000 +0530
@@ -1535,6 +1535,8 @@
return -EFAULT;
timeout = timespec_to_jiffies(&t) + 1;
}
+ if (op == FUTEX_WAIT_ROBUST && utime == NULL)
+ timeout = 0;
/*
* requeue parameter in 'utime' if op == FUTEX_REQUEUE.
*/
next reply other threads:[~2005-12-07 19:15 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-12-07 19:34 Dinakar Guniguntala [this message]
2005-12-11 13:51 ` [PATCH] Fix timeout in robust path Ingo Molnar
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=20051207193429.GD4897@in.ibm.com \
--to=dino@in.ibm.com \
--cc=dsingleton@mvista.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox