| Message ID | 20230919012525.1783108-1-chengzhihao1@huawei.com |
|---|---|
| State | Awaiting Upstream |
| Headers | show |
| Series | [v3] jbd2: Fix potential data lost in recovering journal raced with synchronizing fs bdev | expand |
On Tue 19-09-23 09:25:25, Zhihao Cheng wrote: > JBD2 makes sure journal data is fallen on fs device by sync_blockdev(), > however, other process could intercept the EIO information from bdev's > mapping, which leads journal recovering successful even EIO occurs during > data written back to fs device. > > We found this problem in our product, iscsi + multipath is chosen for block > device of ext4. Unstable network may trigger kpartx to rescan partitions in > device mapper layer. Detailed process is shown as following: > > mount kpartx irq > jbd2_journal_recover > do_one_pass > memcpy(nbh->b_data, obh->b_data) // copy data to fs dev from journal > mark_buffer_dirty // mark bh dirty > vfs_read > generic_file_read_iter // dio > filemap_write_and_wait_range > __filemap_fdatawrite_range > do_writepages > block_write_full_folio > submit_bh_wbc > >> EIO occurs in disk << > end_buffer_async_write > mark_buffer_write_io_error > mapping_set_error > set_bit(AS_EIO, &mapping->flags) // set! > filemap_check_errors > test_and_clear_bit(AS_EIO, &mapping->flags) // clear! > err2 = sync_blockdev > filemap_write_and_wait > filemap_check_errors > test_and_clear_bit(AS_EIO, &mapping->flags) // false > err2 = 0 > > Filesystem is mounted successfully even data from journal is failed written > into disk, and ext4/ocfs2 could become corrupted. > > Fix it by comparing the wb_err state in fs block device before recovering > and after recovering. > > Fetch a reproducer in [Link]. > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=217888 > Cc: stable@vger.kernel.org > Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> > Signed-off-by: Zhang Yi <yi.zhang@huawei.com> > --- > v1->v3: Initialize wb_err. Untialized wb_err could be same with > mapping->wb_err(eg. EIO without ERRSEQ_SEEN). When EIO > occurs again, mapping->wb_err won't be changed, and wb_err > is still same with mapping->wb_err. Yeah, good catch. The patch still looks good to me. Feel free to add: Reviewed-by: Jan Kara <jack@suse.cz> Honza > fs/jbd2/recovery.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c > index c269a7d29a46..5b771a3d8d9a 100644 > --- a/fs/jbd2/recovery.c > +++ b/fs/jbd2/recovery.c > @@ -289,6 +289,8 @@ int jbd2_journal_recover(journal_t *journal) > journal_superblock_t * sb; > > struct recovery_info info; > + errseq_t wb_err; > + struct address_space *mapping; > > memset(&info, 0, sizeof(info)); > sb = journal->j_superblock; > @@ -306,6 +308,9 @@ int jbd2_journal_recover(journal_t *journal) > return 0; > } > > + wb_err = 0; > + mapping = journal->j_fs_dev->bd_inode->i_mapping; > + errseq_check_and_advance(&mapping->wb_err, &wb_err); > err = do_one_pass(journal, &info, PASS_SCAN); > if (!err) > err = do_one_pass(journal, &info, PASS_REVOKE); > @@ -327,6 +332,9 @@ int jbd2_journal_recover(journal_t *journal) > > jbd2_journal_clear_revoke(journal); > err2 = sync_blockdev(journal->j_fs_dev); > + if (!err) > + err = err2; > + err2 = errseq_check_and_advance(&mapping->wb_err, &wb_err); > if (!err) > err = err2; > /* Make sure all replayed data is on permanent storage */ > -- > 2.39.2 >
On Tue, 19 Sep 2023 09:25:25 +0800, Zhihao Cheng wrote: > JBD2 makes sure journal data is fallen on fs device by sync_blockdev(), > however, other process could intercept the EIO information from bdev's > mapping, which leads journal recovering successful even EIO occurs during > data written back to fs device. > > We found this problem in our product, iscsi + multipath is chosen for block > device of ext4. Unstable network may trigger kpartx to rescan partitions in > device mapper layer. Detailed process is shown as following: > > [...] Applied, thanks! [1/1] jbd2: Fix potential data lost in recovering journal raced with synchronizing fs bdev commit: 61187fce8600e8ef90e601be84f9d0f3222c1206 Best regards,
diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c index c269a7d29a46..5b771a3d8d9a 100644 --- a/fs/jbd2/recovery.c +++ b/fs/jbd2/recovery.c @@ -289,6 +289,8 @@ int jbd2_journal_recover(journal_t *journal) journal_superblock_t * sb; struct recovery_info info; + errseq_t wb_err; + struct address_space *mapping; memset(&info, 0, sizeof(info)); sb = journal->j_superblock; @@ -306,6 +308,9 @@ int jbd2_journal_recover(journal_t *journal) return 0; } + wb_err = 0; + mapping = journal->j_fs_dev->bd_inode->i_mapping; + errseq_check_and_advance(&mapping->wb_err, &wb_err); err = do_one_pass(journal, &info, PASS_SCAN); if (!err) err = do_one_pass(journal, &info, PASS_REVOKE); @@ -327,6 +332,9 @@ int jbd2_journal_recover(journal_t *journal) jbd2_journal_clear_revoke(journal); err2 = sync_blockdev(journal->j_fs_dev); + if (!err) + err = err2; + err2 = errseq_check_and_advance(&mapping->wb_err, &wb_err); if (!err) err = err2; /* Make sure all replayed data is on permanent storage */
JBD2 makes sure journal data is fallen on fs device by sync_blockdev(), however, other process could intercept the EIO information from bdev's mapping, which leads journal recovering successful even EIO occurs during data written back to fs device. We found this problem in our product, iscsi + multipath is chosen for block device of ext4. Unstable network may trigger kpartx to rescan partitions in device mapper layer. Detailed process is shown as following: mount kpartx irq jbd2_journal_recover do_one_pass memcpy(nbh->b_data, obh->b_data) // copy data to fs dev from journal mark_buffer_dirty // mark bh dirty vfs_read generic_file_read_iter // dio filemap_write_and_wait_range __filemap_fdatawrite_range do_writepages block_write_full_folio submit_bh_wbc >> EIO occurs in disk << end_buffer_async_write mark_buffer_write_io_error mapping_set_error set_bit(AS_EIO, &mapping->flags) // set! filemap_check_errors test_and_clear_bit(AS_EIO, &mapping->flags) // clear! err2 = sync_blockdev filemap_write_and_wait filemap_check_errors test_and_clear_bit(AS_EIO, &mapping->flags) // false err2 = 0 Filesystem is mounted successfully even data from journal is failed written into disk, and ext4/ocfs2 could become corrupted. Fix it by comparing the wb_err state in fs block device before recovering and after recovering. Fetch a reproducer in [Link]. Link: https://bugzilla.kernel.org/show_bug.cgi?id=217888 Cc: stable@vger.kernel.org Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> --- v1->v3: Initialize wb_err. Untialized wb_err could be same with mapping->wb_err(eg. EIO without ERRSEQ_SEEN). When EIO occurs again, mapping->wb_err won't be changed, and wb_err is still same with mapping->wb_err. fs/jbd2/recovery.c | 8 ++++++++ 1 file changed, 8 insertions(+)