mirror of
https://git.yoctoproject.org/meta-ti
synced 2026-07-17 06:48:07 +00:00
Koen Kooi
6203cbca5c
Signed-off-by: Koen Kooi <koen@dominion.thruhere.net> Signed-off-by: Denys Dmytriyenko <denys@ti.com>
117 lines
3.5 KiB
Diff
117 lines
3.5 KiB
Diff
From 898f4d272514d19aafee8cd66b796c0553fca080 Mon Sep 17 00:00:00 2001
|
|
From: Jeff Moyer <jmoyer@redhat.com>
|
|
Date: Thu, 12 Jul 2012 09:43:14 -0400
|
|
Subject: [PATCH 046/109] block: fix infinite loop in __getblk_slow
|
|
|
|
commit 91f68c89d8f35fe98ea04159b9a3b42d0149478f upstream.
|
|
|
|
Commit 080399aaaf35 ("block: don't mark buffers beyond end of disk as
|
|
mapped") exposed a bug in __getblk_slow that causes mount to hang as it
|
|
loops infinitely waiting for a buffer that lies beyond the end of the
|
|
disk to become uptodate.
|
|
|
|
The problem was initially reported by Torsten Hilbrich here:
|
|
|
|
https://lkml.org/lkml/2012/6/18/54
|
|
|
|
and also reported independently here:
|
|
|
|
http://www.sysresccd.org/forums/viewtopic.php?f=13&t=4511
|
|
|
|
and then Richard W.M. Jones and Marcos Mello noted a few separate
|
|
bugzillas also associated with the same issue. This patch has been
|
|
confirmed to fix:
|
|
|
|
https://bugzilla.redhat.com/show_bug.cgi?id=835019
|
|
|
|
The main problem is here, in __getblk_slow:
|
|
|
|
for (;;) {
|
|
struct buffer_head * bh;
|
|
int ret;
|
|
|
|
bh = __find_get_block(bdev, block, size);
|
|
if (bh)
|
|
return bh;
|
|
|
|
ret = grow_buffers(bdev, block, size);
|
|
if (ret < 0)
|
|
return NULL;
|
|
if (ret == 0)
|
|
free_more_memory();
|
|
}
|
|
|
|
__find_get_block does not find the block, since it will not be marked as
|
|
mapped, and so grow_buffers is called to fill in the buffers for the
|
|
associated page. I believe the for (;;) loop is there primarily to
|
|
retry in the case of memory pressure keeping grow_buffers from
|
|
succeeding. However, we also continue to loop for other cases, like the
|
|
block lying beond the end of the disk. So, the fix I came up with is to
|
|
only loop when grow_buffers fails due to memory allocation issues
|
|
(return value of 0).
|
|
|
|
The attached patch was tested by myself, Torsten, and Rich, and was
|
|
found to resolve the problem in call cases.
|
|
|
|
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
|
|
Reported-and-Tested-by: Torsten Hilbrich <torsten.hilbrich@secunet.com>
|
|
Tested-by: Richard W.M. Jones <rjones@redhat.com>
|
|
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
|
|
[ Jens is on vacation, taking this directly - Linus ]
|
|
--
|
|
Stable Notes: this patch requires backport to 3.0, 3.2 and 3.3.
|
|
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
|
|
---
|
|
fs/buffer.c | 22 +++++++++++++---------
|
|
1 files changed, 13 insertions(+), 9 deletions(-)
|
|
|
|
diff --git a/fs/buffer.c b/fs/buffer.c
|
|
index c807931..4115eca 100644
|
|
--- a/fs/buffer.c
|
|
+++ b/fs/buffer.c
|
|
@@ -1087,6 +1087,9 @@ grow_buffers(struct block_device *bdev, sector_t block, int size)
|
|
static struct buffer_head *
|
|
__getblk_slow(struct block_device *bdev, sector_t block, int size)
|
|
{
|
|
+ int ret;
|
|
+ struct buffer_head *bh;
|
|
+
|
|
/* Size must be multiple of hard sectorsize */
|
|
if (unlikely(size & (bdev_logical_block_size(bdev)-1) ||
|
|
(size < 512 || size > PAGE_SIZE))) {
|
|
@@ -1099,20 +1102,21 @@ __getblk_slow(struct block_device *bdev, sector_t block, int size)
|
|
return NULL;
|
|
}
|
|
|
|
- for (;;) {
|
|
- struct buffer_head * bh;
|
|
- int ret;
|
|
+retry:
|
|
+ bh = __find_get_block(bdev, block, size);
|
|
+ if (bh)
|
|
+ return bh;
|
|
|
|
+ ret = grow_buffers(bdev, block, size);
|
|
+ if (ret == 0) {
|
|
+ free_more_memory();
|
|
+ goto retry;
|
|
+ } else if (ret > 0) {
|
|
bh = __find_get_block(bdev, block, size);
|
|
if (bh)
|
|
return bh;
|
|
-
|
|
- ret = grow_buffers(bdev, block, size);
|
|
- if (ret < 0)
|
|
- return NULL;
|
|
- if (ret == 0)
|
|
- free_more_memory();
|
|
}
|
|
+ return NULL;
|
|
}
|
|
|
|
/*
|
|
--
|
|
1.7.7.6
|
|
|