Bug#317062: umount -a hangs in strcmp with 2.6.11/12
tags 317062 patch thanks On Fri, Dec 09, 2005 at 11:18:43AM +, Colin Watson wrote: > On Wed, Jul 06, 2005 at 01:37:58AM +0300, Joey Hess wrote: > > On 2.6.11 or 2.6.12 on i386, in d-i, but ONLY if the d-i image is built > > to use initramfs, and not it if uses a regular initrd, when /proc, > > /dev/pts and /dev are mounted, umount -a hangs. strace shows it has > > called umount syscall on each of these; /dev and /dev/pts are busy and > > fail. ltrace shows it spinning in a strcmp loop. gdb shows it hanging in > > mtab_getinfo, looks like the linked list has a loop in it. > > I finally got fed up of the workarounds and decided to track this down. > In fact it doesn't look like the linked list has a loop, but rather that > mtab_getinfo just forgets to step its cur pointer if it encounters a > rootfs. Patch follows (untested as yet, but I'm in the process of > testing it now): This patch works. Please apply it. Cheers, -- Colin Watson [EMAIL PROTECTED] -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Bug#317062: umount -a hangs in strcmp with 2.6.11/12
On Wed, Jul 06, 2005 at 01:37:58AM +0300, Joey Hess wrote:
> Package: busybox-udeb
> Version: 1:1.00-3
> Severity: important
> Tags: d-i
>
> On 2.6.11 or 2.6.12 on i386, in d-i, but ONLY if the d-i image is built
> to use initramfs, and not it if uses a regular initrd, when /proc,
> /dev/pts and /dev are mounted, umount -a hangs. strace shows it has
> called umount syscall on each of these; /dev and /dev/pts are busy and
> fail. ltrace shows it spinning in a strcmp loop. gdb shows it hanging in
> mtab_getinfo, looks like the linked list has a loop in it.
I finally got fed up of the workarounds and decided to track this down.
In fact it doesn't look like the linked list has a loop, but rather that
mtab_getinfo just forgets to step its cur pointer if it encounters a
rootfs. Patch follows (untested as yet, but I'm in the process of
testing it now):
diff -u busybox-1.01/debian/changelog busybox-1.01/debian/changelog
--- busybox-1.01/debian/changelog
+++ busybox-1.01/debian/changelog
@@ -1,3 +1,9 @@
+busybox (1:1.01-3.1) UNRELEASED; urgency=low
+
+ * Fix infinite loop in umount -a when encountering a rootfs mount point.
+
+ -- Colin Watson <[EMAIL PROTECTED]> Fri, 9 Dec 2005 11:14:08 +
+
busybox (1:1.01-3) unstable; urgency=low
* debian/config-deb:
diff -u busybox-1.01/util-linux/umount.c busybox-1.01/util-linux/umount.c
--- busybox-1.01/util-linux/umount.c
+++ busybox-1.01/util-linux/umount.c
@@ -111,6 +111,7 @@
} else {
#if !defined CONFIG_FEATURE_MTAB_SUPPORT
if (strcmp(cur->device, "rootfs") == 0) {
+ cur = cur->next;
continue;
} else if (strcmp(cur->device, "/dev/root") ==
0) {
/* Adjusts device to be the real root
device,
Cheers,
--
Colin Watson [EMAIL PROTECTED]
--
To UNSUBSCRIBE, email to [EMAIL PROTECTED]
with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Bug#317062: umount -a hangs in strcmp with 2.6.11/12
Package: busybox-udeb Version: 1:1.00-3 Severity: important Tags: d-i On 2.6.11 or 2.6.12 on i386, in d-i, but ONLY if the d-i image is built to use initramfs, and not it if uses a regular initrd, when /proc, /dev/pts and /dev are mounted, umount -a hangs. strace shows it has called umount syscall on each of these; /dev and /dev/pts are busy and fail. ltrace shows it spinning in a strcmp loop. gdb shows it hanging in mtab_getinfo, looks like the linked list has a loop in it. -- System Information: Debian Release: testing/unstable APT prefers unstable APT policy: (500, 'unstable'), (1, 'experimental') Architecture: i386 (i686) Shell: /bin/sh linked to /bin/bash Kernel: Linux 2.4.27 Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) -- see shy jo signature.asc Description: Digital signature
