This is a note to let you know that I've just added the patch titled ext4: move error report out of atomic context in ext4_init_block_bitmap() to the 3.17-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ext4-move-error-report-out-of-atomic-context-in-ext4_init_block_bitmap.patch and it can be found in the queue-3.17 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From aef4885ae14f1df75b58395c5314d71f613d26d9 Mon Sep 17 00:00:00 2001 From: Dmitry Monakhov <dmonakhov@xxxxxxxxxx> Date: Mon, 13 Oct 2014 03:42:12 -0400 Subject: ext4: move error report out of atomic context in ext4_init_block_bitmap() From: Dmitry Monakhov <dmonakhov@xxxxxxxxxx> commit aef4885ae14f1df75b58395c5314d71f613d26d9 upstream. Error report likely result in IO so it is bad idea to do it from atomic context. This patch should fix following issue: BUG: sleeping function called from invalid context at include/linux/buffer_head.h:349 in_atomic(): 1, irqs_disabled(): 0, pid: 137, name: kworker/u128:1 5 locks held by kworker/u128:1/137: #0: ("writeback"){......}, at: [<ffffffff81085618>] process_one_work+0x228/0x4d0 #1: ((&(&wb->dwork)->work)){......}, at: [<ffffffff81085618>] process_one_work+0x228/0x4d0 #2: (jbd2_handle){......}, at: [<ffffffff81242622>] start_this_handle+0x712/0x7b0 #3: (&ei->i_data_sem){......}, at: [<ffffffff811fa387>] ext4_map_blocks+0x297/0x430 #4: (&(&bgl->locks[i].lock)->rlock){......}, at: [<ffffffff811f3180>] ext4_read_block_bitmap_nowait+0x5d0/0x630 CPU: 3 PID: 137 Comm: kworker/u128:1 Not tainted 3.17.0-rc2-00184-g82752e4 #165 Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.99.99.x028.061320111235 06/13/2011 Workqueue: writeback bdi_writeback_workfn (flush-1:0) 0000000000000411 ffff880813777288 ffffffff815c7fdc ffff880813777288 ffff880813a8bba0 ffff8808137772a8 ffffffff8108fb30 ffff880803e01e38 ffff880803e01e38 ffff8808137772c8 ffffffff811a8d53 ffff88080ecc6000 Call Trace: [<ffffffff815c7fdc>] dump_stack+0x51/0x6d [<ffffffff8108fb30>] __might_sleep+0xf0/0x100 [<ffffffff811a8d53>] __sync_dirty_buffer+0x43/0xe0 [<ffffffff811a8e03>] sync_dirty_buffer+0x13/0x20 [<ffffffff8120f581>] ext4_commit_super+0x1d1/0x230 [<ffffffff8120fa03>] save_error_info+0x23/0x30 [<ffffffff8120fd06>] __ext4_error+0xb6/0xd0 [<ffffffff8120f260>] ? ext4_group_desc_csum+0x140/0x190 [<ffffffff811f2d8c>] ext4_read_block_bitmap_nowait+0x1dc/0x630 [<ffffffff8122e23a>] ext4_mb_init_cache+0x21a/0x8f0 [<ffffffff8113ae95>] ? lru_cache_add+0x55/0x60 [<ffffffff8112e16c>] ? add_to_page_cache_lru+0x6c/0x80 [<ffffffff8122eaa0>] ext4_mb_init_group+0x190/0x280 [<ffffffff8122ec51>] ext4_mb_good_group+0xc1/0x190 [<ffffffff8123309a>] ext4_mb_regular_allocator+0x17a/0x410 [<ffffffff8122c821>] ? ext4_mb_use_preallocated+0x31/0x380 [<ffffffff81233535>] ? ext4_mb_new_blocks+0x205/0x8e0 [<ffffffff8116ed5c>] ? kmem_cache_alloc+0xfc/0x180 [<ffffffff812335b0>] ext4_mb_new_blocks+0x280/0x8e0 [<ffffffff8116f2c4>] ? __kmalloc+0x144/0x1c0 [<ffffffff81221797>] ? ext4_find_extent+0x97/0x320 [<ffffffff812257f4>] ext4_ext_map_blocks+0xbc4/0x1050 [<ffffffff811fa387>] ? ext4_map_blocks+0x297/0x430 [<ffffffff811fa3ab>] ext4_map_blocks+0x2bb/0x430 [<ffffffff81200e43>] ? ext4_init_io_end+0x23/0x50 [<ffffffff811feb44>] ext4_writepages+0x564/0xaf0 [<ffffffff815cde3b>] ? _raw_spin_unlock+0x2b/0x40 [<ffffffff810ac7bd>] ? lock_release_non_nested+0x2fd/0x3c0 [<ffffffff811a009e>] ? writeback_sb_inodes+0x10e/0x490 [<ffffffff811a009e>] ? writeback_sb_inodes+0x10e/0x490 [<ffffffff811377e3>] do_writepages+0x23/0x40 [<ffffffff8119c8ce>] __writeback_single_inode+0x9e/0x280 [<ffffffff811a026b>] writeback_sb_inodes+0x2db/0x490 [<ffffffff811a0664>] wb_writeback+0x174/0x2d0 [<ffffffff810ac359>] ? lock_release_holdtime+0x29/0x190 [<ffffffff811a0863>] wb_do_writeback+0xa3/0x200 [<ffffffff811a0a40>] bdi_writeback_workfn+0x80/0x230 [<ffffffff81085618>] ? process_one_work+0x228/0x4d0 [<ffffffff810856cd>] process_one_work+0x2dd/0x4d0 [<ffffffff81085618>] ? process_one_work+0x228/0x4d0 [<ffffffff81085c1d>] worker_thread+0x35d/0x460 [<ffffffff810858c0>] ? process_one_work+0x4d0/0x4d0 [<ffffffff810858c0>] ? process_one_work+0x4d0/0x4d0 [<ffffffff8108a885>] kthread+0xf5/0x100 [<ffffffff810990e5>] ? local_clock+0x25/0x30 [<ffffffff8108a790>] ? __init_kthread_worker+0x70/0x70 [<ffffffff815ce2ac>] ret_from_fork+0x7c/0xb0 [<ffffffff8108a790>] ? __init_kthread_work Signed-off-by: Dmitry Monakhov <dmonakhov@xxxxxxxxxx> Signed-off-by: Theodore Ts'o <tytso@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/ext4/balloc.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -176,7 +176,7 @@ static unsigned int num_clusters_in_grou } /* Initializes an uninitialized block bitmap */ -static void ext4_init_block_bitmap(struct super_block *sb, +static int ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, ext4_group_t block_group, struct ext4_group_desc *gdp) @@ -192,7 +192,6 @@ static void ext4_init_block_bitmap(struc /* If checksum is bad mark all blocks used to prevent allocation * essentially implementing a per-group read-only flag. */ if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) { - ext4_error(sb, "Checksum bad for group %u", block_group); grp = ext4_get_group_info(sb, block_group); if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp)) percpu_counter_sub(&sbi->s_freeclusters_counter, @@ -205,7 +204,7 @@ static void ext4_init_block_bitmap(struc count); } set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state); - return; + return -EIO; } memset(bh->b_data, 0, sb->s_blocksize); @@ -243,6 +242,7 @@ static void ext4_init_block_bitmap(struc sb->s_blocksize * 8, bh->b_data); ext4_block_bitmap_csum_set(sb, block_group, gdp, bh); ext4_group_desc_csum_set(sb, block_group, gdp); + return 0; } /* Return the number of free blocks in a block group. It is used when @@ -438,11 +438,15 @@ ext4_read_block_bitmap_nowait(struct sup } ext4_lock_group(sb, block_group); if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { - ext4_init_block_bitmap(sb, bh, block_group, desc); + int err; + + err = ext4_init_block_bitmap(sb, bh, block_group, desc); set_bitmap_uptodate(bh); set_buffer_uptodate(bh); ext4_unlock_group(sb, block_group); unlock_buffer(bh); + if (err) + ext4_error(sb, "Checksum bad for grp %u", block_group); return bh; } ext4_unlock_group(sb, block_group); Patches currently in stable-queue which might be from dmonakhov@xxxxxxxxxx are queue-3.17/ext4-check-s_chksum_driver-when-looking-for-bg-csum-presence.patch queue-3.17/ext4-prevent-bugon-on-race-between-write-fcntl.patch queue-3.17/ext4-move-error-report-out-of-atomic-context-in-ext4_init_block_bitmap.patch queue-3.17/ext4-replace-open-coded-mdata-csum-feature-to-helper-function.patch queue-3.17/ext4-grab-missed-write_count-for-ext4_ioc_swap_boot.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html