The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x fcced95b6ba2a507a83b8b3e0358a8ac16b13e35 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2023072139-gently-poster-a61c@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: fcced95b6ba2 ("ext2/dax: Fix ext2_setsize when len is page aligned") 0cc5b4ce7a37 ("ext2: remove nobh support") 67235182a41c ("mm/migrate: Convert buffer_migrate_page() to buffer_migrate_folio()") eca66389744d ("ocfs2: Convert to release_folio") f132ab7d3ab0 ("fs: Convert mpage_readpage to mpage_read_folio") 9d6b0cd75798 ("fs: Remove flags parameter from aops->write_begin") 8371f30cf774 ("fs: Remove aop flags parameter from nobh_write_begin()") e621900ad28b ("fs: Convert __set_page_dirty_buffers to block_dirty_folio") 7ba13abbd31e ("fs: Turn block_invalidatepage into block_invalidate_folio") 128d1f8241d6 ("fs: Add invalidate_folio() aops method") 5ad6b2bdaaea ("fs: Turn do_invalidatepage() into folio_invalidate()") 3acbdbf42e94 ("Merge tag 'libnvdimm-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From fcced95b6ba2a507a83b8b3e0358a8ac16b13e35 Mon Sep 17 00:00:00 2001 From: "Ritesh Harjani (IBM)" <ritesh.list@xxxxxxxxx> Date: Fri, 21 Apr 2023 15:16:11 +0530 Subject: [PATCH] ext2/dax: Fix ext2_setsize when len is page aligned PAGE_ALIGN(x) macro gives the next highest value which is multiple of pagesize. But if x is already page aligned then it simply returns x. So, if x passed is 0 in dax_zero_range() function, that means the length gets passed as 0 to ->iomap_begin(). In ext2 it then calls ext2_get_blocks -> max_blocks as 0 and hits bug_on here in ext2_get_blocks(). BUG_ON(maxblocks == 0); Instead we should be calling dax_truncate_page() here which takes care of it. i.e. it only calls dax_zero_range if the offset is not page/block aligned. This can be easily triggered with following on fsdax mounted pmem device. dd if=/dev/zero of=file count=1 bs=512 truncate -s 0 file [79.525838] EXT2-fs (pmem0): DAX enabled. Warning: EXPERIMENTAL, use at your own risk [79.529376] ext2 filesystem being mounted at /mnt1/test supports timestamps until 2038 (0x7fffffff) [93.793207] ------------[ cut here ]------------ [93.795102] kernel BUG at fs/ext2/inode.c:637! [93.796904] invalid opcode: 0000 [#1] PREEMPT SMP PTI [93.798659] CPU: 0 PID: 1192 Comm: truncate Not tainted 6.3.0-rc2-xfstests-00056-g131086faa369 #139 [93.806459] RIP: 0010:ext2_get_blocks.constprop.0+0x524/0x610 <...> [93.835298] Call Trace: [93.836253] <TASK> [93.837103] ? lock_acquire+0xf8/0x110 [93.838479] ? d_lookup+0x69/0xd0 [93.839779] ext2_iomap_begin+0xa7/0x1c0 [93.841154] iomap_iter+0xc7/0x150 [93.842425] dax_zero_range+0x6e/0xa0 [93.843813] ext2_setsize+0x176/0x1b0 [93.845164] ext2_setattr+0x151/0x200 [93.846467] notify_change+0x341/0x4e0 [93.847805] ? lock_acquire+0xf8/0x110 [93.849143] ? do_truncate+0x74/0xe0 [93.850452] ? do_truncate+0x84/0xe0 [93.851739] do_truncate+0x84/0xe0 [93.852974] do_sys_ftruncate+0x2b4/0x2f0 [93.854404] do_syscall_64+0x3f/0x90 [93.855789] entry_SYSCALL_64_after_hwframe+0x72/0xdc CC: stable@xxxxxxxxxxxxxxx Fixes: 2aa3048e03d3 ("iomap: switch iomap_zero_range to use iomap_iter") Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx> Signed-off-by: Jan Kara <jack@xxxxxxx> Message-Id: <046a58317f29d9603d1068b2bbae47c2332c17ae.1682069716.git.ritesh.list@xxxxxxxxx> diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c index 26f135e7ffce..dc76147e7b07 100644 --- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -1259,9 +1259,8 @@ static int ext2_setsize(struct inode *inode, loff_t newsize) inode_dio_wait(inode); if (IS_DAX(inode)) - error = dax_zero_range(inode, newsize, - PAGE_ALIGN(newsize) - newsize, NULL, - &ext2_iomap_ops); + error = dax_truncate_page(inode, newsize, NULL, + &ext2_iomap_ops); else error = block_truncate_page(inode->i_mapping, newsize, ext2_get_block);