[ 77/95] fs/buffer.c: remove BUG() in possible but rare condition
3.2-stable review patch. If anyone has any objections, please let me know. -- From: Glauber Costa commit 61065a30af8df4b8989c2ac7a1f4b4034e4df2d5 upstream. While stressing the kernel with with failing allocations today, I hit the following chain of events: alloc_page_buffers(): bh = alloc_buffer_head(GFP_NOFS); if (!bh) goto no_grow; <= path taken grow_dev_page(): bh = alloc_page_buffers(page, size, 0); if (!bh) goto failed; <= taken, consequence of the above and then the failed path BUG()s the kernel. The failure is inserted a litte bit artificially, but even then, I see no reason why it should be deemed impossible in a real box. Even though this is not a condition that we expect to see around every time, failed allocations are expected to be handled, and BUG() sounds just too much. As a matter of fact, grow_dev_page() can return NULL just fine in other circumstances, so I propose we just remove it, then. Signed-off-by: Glauber Costa Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings --- fs/buffer.c |1 - 1 file changed, 1 deletion(-) diff --git a/fs/buffer.c b/fs/buffer.c index 36d6665..351e18e 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -985,7 +985,6 @@ grow_dev_page(struct block_device *bdev, sector_t block, return page; failed: - BUG(); unlock_page(page); page_cache_release(page); return NULL; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[ 77/95] fs/buffer.c: remove BUG() in possible but rare condition
3.2-stable review patch. If anyone has any objections, please let me know. -- From: Glauber Costa glom...@parallels.com commit 61065a30af8df4b8989c2ac7a1f4b4034e4df2d5 upstream. While stressing the kernel with with failing allocations today, I hit the following chain of events: alloc_page_buffers(): bh = alloc_buffer_head(GFP_NOFS); if (!bh) goto no_grow; = path taken grow_dev_page(): bh = alloc_page_buffers(page, size, 0); if (!bh) goto failed; = taken, consequence of the above and then the failed path BUG()s the kernel. The failure is inserted a litte bit artificially, but even then, I see no reason why it should be deemed impossible in a real box. Even though this is not a condition that we expect to see around every time, failed allocations are expected to be handled, and BUG() sounds just too much. As a matter of fact, grow_dev_page() can return NULL just fine in other circumstances, so I propose we just remove it, then. Signed-off-by: Glauber Costa glom...@parallels.com Cc: Michal Hocko mho...@suse.cz Signed-off-by: Andrew Morton a...@linux-foundation.org Signed-off-by: Linus Torvalds torva...@linux-foundation.org Signed-off-by: Ben Hutchings b...@decadent.org.uk --- fs/buffer.c |1 - 1 file changed, 1 deletion(-) diff --git a/fs/buffer.c b/fs/buffer.c index 36d6665..351e18e 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -985,7 +985,6 @@ grow_dev_page(struct block_device *bdev, sector_t block, return page; failed: - BUG(); unlock_page(page); page_cache_release(page); return NULL; -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
