summaryrefslogtreecommitdiffstats
path: root/fs (follow)
Commit message (Collapse)AuthorAgeFilesLines
* ext4: add IOMAP_F_MERGED for non-extent based mappingRitesh Harjani2020-03-141-0/+4
| | | | | | | | | | | IOMAP_F_MERGED needs to be set in case of non-extent based mapping. This is needed in later patches for conversion of ext4_fiemap to use iomap. Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/a4764c91c08c16d4d4a4b36defb2a08625b0e9b3.1582880246.git.riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix a data race at inode->i_disksizeQiujun Huang2020-03-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KCSAN find inode->i_disksize could be accessed concurrently. BUG: KCSAN: data-race in ext4_mark_iloc_dirty / ext4_write_end write (marked) to 0xffff8b8932f40090 of 8 bytes by task 66792 on cpu 0: ext4_write_end+0x53f/0x5b0 ext4_da_write_end+0x237/0x510 generic_perform_write+0x1c4/0x2a0 ext4_buffered_write_iter+0x13a/0x210 ext4_file_write_iter+0xe2/0x9b0 new_sync_write+0x29c/0x3a0 __vfs_write+0x92/0xa0 vfs_write+0xfc/0x2a0 ksys_write+0xe8/0x140 __x64_sys_write+0x4c/0x60 do_syscall_64+0x8a/0x2a0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff8b8932f40090 of 8 bytes by task 14414 on cpu 1: ext4_mark_iloc_dirty+0x716/0x1190 ext4_mark_inode_dirty+0xc9/0x360 ext4_convert_unwritten_extents+0x1bc/0x2a0 ext4_convert_unwritten_io_end_vec+0xc5/0x150 ext4_put_io_end+0x82/0x130 ext4_writepages+0xae7/0x16f0 do_writepages+0x64/0x120 __writeback_single_inode+0x7d/0x650 writeback_sb_inodes+0x3a4/0x860 __writeback_inodes_wb+0xc4/0x150 wb_writeback+0x43f/0x510 wb_workfn+0x3b2/0x8a0 process_one_work+0x39b/0x7e0 worker_thread+0x88/0x650 kthread+0x1d4/0x1f0 ret_from_fork+0x35/0x40 The plain read is outside of inode->i_data_sem critical section which results in a data race. Fix it by adding READ_ONCE(). Signed-off-by: Qiujun Huang <hqjagain@gmail.com> Link: https://lore.kernel.org/r/1582556566-3909-1-git-send-email-hqjagain@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: fix a data race at inode->i_blocksQian Cai2020-03-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | inode->i_blocks could be accessed concurrently as noticed by KCSAN, BUG: KCSAN: data-race in ext4_do_update_inode [ext4] / inode_add_bytes write to 0xffff9a00d4b982d0 of 8 bytes by task 22100 on cpu 118: inode_add_bytes+0x65/0xf0 __inode_add_bytes at fs/stat.c:689 (inlined by) inode_add_bytes at fs/stat.c:702 ext4_mb_new_blocks+0x418/0xca0 [ext4] ext4_ext_map_blocks+0x1a6b/0x27b0 [ext4] ext4_map_blocks+0x1a9/0x950 [ext4] _ext4_get_block+0xfc/0x270 [ext4] ext4_get_block_unwritten+0x33/0x50 [ext4] __block_write_begin_int+0x22e/0xae0 __block_write_begin+0x39/0x50 ext4_write_begin+0x388/0xb50 [ext4] ext4_da_write_begin+0x35f/0x8f0 [ext4] generic_perform_write+0x15d/0x290 ext4_buffered_write_iter+0x11f/0x210 [ext4] ext4_file_write_iter+0xce/0x9e0 [ext4] new_sync_write+0x29c/0x3b0 __vfs_write+0x92/0xa0 vfs_write+0x103/0x260 ksys_write+0x9d/0x130 __x64_sys_write+0x4c/0x60 do_syscall_64+0x91/0xb05 entry_SYSCALL_64_after_hwframe+0x49/0xbe read to 0xffff9a00d4b982d0 of 8 bytes by task 8 on cpu 65: ext4_do_update_inode+0x4a0/0xf60 [ext4] ext4_inode_blocks_set at fs/ext4/inode.c:4815 ext4_mark_iloc_dirty+0xaf/0x160 [ext4] ext4_mark_inode_dirty+0x129/0x3e0 [ext4] ext4_convert_unwritten_extents+0x253/0x2d0 [ext4] ext4_convert_unwritten_io_end_vec+0xc5/0x150 [ext4] ext4_end_io_rsv_work+0x22c/0x350 [ext4] process_one_work+0x54f/0xb90 worker_thread+0x80/0x5f0 kthread+0x1cd/0x1f0 ret_from_fork+0x27/0x50 4 locks held by kworker/u256:0/8: #0: ffff9a025abc4328 ((wq_completion)ext4-rsv-conversion){+.+.}, at: process_one_work+0x443/0xb90 #1: ffffab5a862dbe20 ((work_completion)(&ei->i_rsv_conversion_work)){+.+.}, at: process_one_work+0x443/0xb90 #2: ffff9a025a9d0f58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2] #3: ffff9a00d4b985d8 (&(&ei->i_raw_lock)->rlock){+.+.}, at: ext4_do_update_inode+0xaa/0xf60 [ext4] irq event stamp: 3009267 hardirqs last enabled at (3009267): [<ffffffff980da9b7>] __find_get_block+0x107/0x790 hardirqs last disabled at (3009266): [<ffffffff980da8f9>] __find_get_block+0x49/0x790 softirqs last enabled at (3009230): [<ffffffff98a0034c>] __do_softirq+0x34c/0x57c softirqs last disabled at (3009223): [<ffffffff97cc67a2>] irq_exit+0xa2/0xc0 Reported by Kernel Concurrency Sanitizer on: CPU: 65 PID: 8 Comm: kworker/u256:0 Tainted: G L 5.6.0-rc2-next-20200221+ #7 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019 Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work [ext4] The plain read is outside of inode->i_lock critical section which results in a data race. Fix it by adding READ_ONCE() there. Link: https://lore.kernel.org/r/20200222043258.2279-1-cai@lca.pw Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
* ext4: clean up error return for convert_initialized_extent()Eric Whitney2020-03-061-9/+9
| | | | | | | | | | | | | | | | | Although convert_initialized_extent() can potentially return an error code with a negative value, its returned value is assigned to an unsigned variable containing a block count in ext4_ext_map_blocks() and then returned to that function's caller. The code currently works, though the way this happens is obscure. The code would be more readable if it followed the error handling convention used elsewhere in ext4_ext_map_blocks(). This patch does not address any known test failure or bug report - it's simply a cleanup. It also addresses a nearby coding standard issue. Signed-off-by: Eric Whitney <enwlinux@gmail.com> Link: https://lore.kernel.org/r/20200218202656.21561-1-enwlinux@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* jbd2: improve comments about freeing data buffers whose page mapping is NULLzhangyi (F)2020-03-061-3/+4
| | | | | | | | | | | | | Improve comments in jbd2_journal_commit_transaction() to describe why we don't need to clear the buffer_mapped bit for freeing file mapping buffers whose page mapping is NULL. Link: https://lore.kernel.org/r/20200217112706.20085-1-yi.zhang@huawei.com Fixes: c96dceeabf76 ("jbd2: do not clear the BH_Mapped flag when forgetting a metadata buffer") Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: zhangyi (F) <yi.zhang@huawei.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: use flexible-array members in struct dx_node and struct dx_rootGustavo A. R. Silva2020-03-061-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Link: https://lore.kernel.org/r/20200213160648.GA7054@embeddedor Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: use built-in RCU list checking in mballocMadhuparna Bhowmik2020-03-061-2/+4
| | | | | | | | | | | | list_for_each_entry_rcu() has built-in RCU and lock checking. Pass cond argument to list_for_each_entry_rcu() to silence false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled by default. Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com> Link: https://lore.kernel.org/r/20200213152558.7070-1-madhuparnabhowmik10@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: delete declaration for ext4_split_extent()Eric Whitney2020-03-051-7/+0
| | | | | | | | | | There are no forward references for ext4_split_extent() in extents.c, so delete its unnecessary declaration. Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Eric Whitney <enwlinux@gmail.com> Link: https://lore.kernel.org/r/20200212162141.22381-1-enwlinux@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: remove EXT4_EOFBLOCKS_FL and associated codeEric Whitney2020-03-054-102/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The EXT4_EOFBLOCKS_FL inode flag is used to indicate whether a file contains unwritten blocks past i_size. It's set when ext4_fallocate is called with the KEEP_SIZE flag to extend a file with an unwritten extent. However, this flag hasn't been useful functionally since March, 2012, when a decision was made to remove it from ext4. All traces of EXT4_EOFBLOCKS_FL were removed from e2fsprogs version 1.42.2 by commit 010dc7b90d97 ("e2fsck: remove EXT4_EOFBLOCKS_FL flag handling") at that time. Now that enough time has passed to make e2fsprogs versions containing this modification common, this patch now removes the code associated with EXT4_EOFBLOCKS_FL from the kernel as well. This change has two implications. First, because pre-1.42.2 e2fsck versions only look for a problem if EXT4_EOFBLOCKS_FL is set, and because that bit will never be set by newer kernels containing this patch, old versions of e2fsck won't have a compatibility problem with files created by newer kernels. Second, newer kernels will not clear EXT4_EOFBLOCKS_FL inode flag bits belonging to a file written by an older kernel. If set, it will remain in that state until the file is deleted. Because e2fsck versions since 1.42.2 don't check the flag at all, no adverse effect is expected. However, pre-1.42.2 e2fsck versions that do check the flag may report that it is set when it ought not to be after a file has been truncated or had its unwritten blocks written. In this case, the old version of e2fsck will offer to clear the flag. No adverse effect would then occur whether the user chooses to clear the flag or not. Signed-off-by: Eric Whitney <enwlinux@gmail.com> Link: https://lore.kernel.org/r/20200211210216.24960-1-enwlinux@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: code cleanup for ext4_statfs_project()Chengguang Xu2020-03-051-9/+4
| | | | | | | | | Calling min_not_zero() to simplify complicated prjquota limit comparison in ext4_statfs_project(). Signed-off-by: Chengguang Xu <cgxu519@mykernel.net> Link: https://lore.kernel.org/r/20200210082445.2379-1-cgxu519@mykernel.net Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: start to support iopoll methodXiaoguang Wang2020-03-051-0/+1
| | | | | | | | | | | Since commit "b1b4705d54ab ext4: introduce direct I/O read using iomap infrastructure", we can easily make ext4 support iopoll method, just use iomap_dio_iopoll(). Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com> Link: https://lore.kernel.org/r/20200207120758.2411-1-xiaoguang.wang@linux.alibaba.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* ext4: force buffer up-to-date while marking it dirtyHarshad Shirwadkar2020-03-051-0/+1
| | | | | | | | | | Writeback errors can leave buffer in not up-to-date state when there are errors during background writes. Force buffer up-to-date while marking it dirty. Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Link: https://lore.kernel.org/r/20191224190940.157952-1-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* Merge tag 'ext4_for_linus_stable' of ↵Linus Torvalds2020-03-012-7/+7
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 fixes from Ted Ts'o: "Two more bug fixes (including a regression) for 5.6" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: potential crash on allocation error in ext4_alloc_flex_bg_array() jbd2: fix data races at struct journal_head
| * ext4: potential crash on allocation error in ext4_alloc_flex_bg_array()Dan Carpenter2020-02-291-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If sbi->s_flex_groups_allocated is zero and the first allocation fails then this code will crash. The problem is that "i--" will set "i" to -1 but when we compare "i >= sbi->s_flex_groups_allocated" then the -1 is type promoted to unsigned and becomes UINT_MAX. Since UINT_MAX is more than zero, the condition is true so we call kvfree(new_groups[-1]). The loop will carry on freeing invalid memory until it crashes. Fixes: 7c990728b99e ("ext4: fix potential race between s_flex_groups online resizing and access") Reviewed-by: Suraj Jitindar Singh <surajjs@amazon.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: stable@kernel.org Link: https://lore.kernel.org/r/20200228092142.7irbc44yaz3by7nb@kili.mountain Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| * jbd2: fix data races at struct journal_headQian Cai2020-02-291-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | journal_head::b_transaction and journal_head::b_next_transaction could be accessed concurrently as noticed by KCSAN, LTP: starting fsync04 /dev/zero: Can't open blockdev EXT4-fs (loop0): mounting ext3 file system using the ext4 subsystem EXT4-fs (loop0): mounted filesystem with ordered data mode. Opts: (null) ================================================================== BUG: KCSAN: data-race in __jbd2_journal_refile_buffer [jbd2] / jbd2_write_access_granted [jbd2] write to 0xffff99f9b1bd0e30 of 8 bytes by task 25721 on cpu 70: __jbd2_journal_refile_buffer+0xdd/0x210 [jbd2] __jbd2_journal_refile_buffer at fs/jbd2/transaction.c:2569 jbd2_journal_commit_transaction+0x2d15/0x3f20 [jbd2] (inlined by) jbd2_journal_commit_transaction at fs/jbd2/commit.c:1034 kjournald2+0x13b/0x450 [jbd2] kthread+0x1cd/0x1f0 ret_from_fork+0x27/0x50 read to 0xffff99f9b1bd0e30 of 8 bytes by task 25724 on cpu 68: jbd2_write_access_granted+0x1b2/0x250 [jbd2] jbd2_write_access_granted at fs/jbd2/transaction.c:1155 jbd2_journal_get_write_access+0x2c/0x60 [jbd2] __ext4_journal_get_write_access+0x50/0x90 [ext4] ext4_mb_mark_diskspace_used+0x158/0x620 [ext4] ext4_mb_new_blocks+0x54f/0xca0 [ext4] ext4_ind_map_blocks+0xc79/0x1b40 [ext4] ext4_map_blocks+0x3b4/0x950 [ext4] _ext4_get_block+0xfc/0x270 [ext4] ext4_get_block+0x3b/0x50 [ext4] __block_write_begin_int+0x22e/0xae0 __block_write_begin+0x39/0x50 ext4_write_begin+0x388/0xb50 [ext4] generic_perform_write+0x15d/0x290 ext4_buffered_write_iter+0x11f/0x210 [ext4] ext4_file_write_iter+0xce/0x9e0 [ext4] new_sync_write+0x29c/0x3b0 __vfs_write+0x92/0xa0 vfs_write+0x103/0x260 ksys_write+0x9d/0x130 __x64_sys_write+0x4c/0x60 do_syscall_64+0x91/0xb05 entry_SYSCALL_64_after_hwframe+0x49/0xbe 5 locks held by fsync04/25724: #0: ffff99f9911093f8 (sb_writers#13){.+.+}, at: vfs_write+0x21c/0x260 #1: ffff99f9db4c0348 (&sb->s_type->i_mutex_key#15){+.+.}, at: ext4_buffered_write_iter+0x65/0x210 [ext4] #2: ffff99f5e7dfcf58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2] #3: ffff99f9db4c0168 (&ei->i_data_sem){++++}, at: ext4_map_blocks+0x176/0x950 [ext4] #4: ffffffff99086b40 (rcu_read_lock){....}, at: jbd2_write_access_granted+0x4e/0x250 [jbd2] irq event stamp: 1407125 hardirqs last enabled at (1407125): [<ffffffff980da9b7>] __find_get_block+0x107/0x790 hardirqs last disabled at (1407124): [<ffffffff980da8f9>] __find_get_block+0x49/0x790 softirqs last enabled at (1405528): [<ffffffff98a0034c>] __do_softirq+0x34c/0x57c softirqs last disabled at (1405521): [<ffffffff97cc67a2>] irq_exit+0xa2/0xc0 Reported by Kernel Concurrency Sanitizer on: CPU: 68 PID: 25724 Comm: fsync04 Tainted: G L 5.6.0-rc2-next-20200221+ #7 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019 The plain reads are outside of jh->b_state_lock critical section which result in data races. Fix them by adding pairs of READ|WRITE_ONCE(). Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Qian Cai <cai@lca.pw> Link: https://lore.kernel.org/r/20200222043111.2227-1-cai@lca.pw Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* | Merge tag 'io_uring-5.6-2020-02-28' of git://git.kernel.dk/linux-blockLinus Torvalds2020-02-283-91/+74
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull io_uring fixes from Jens Axboe: - Fix for a race with IOPOLL used with SQPOLL (Xiaoguang) - Only show ->fdinfo if procfs is enabled (Tobias) - Fix for a chain with multiple personalities in the SQEs - Fix for a missing free of personality idr on exit - Removal of the spin-for-work optimization - Fix for next work lookup on request completion - Fix for non-vec read/write result progation in case of links - Fix for a fileset references on switch - Fix for a recvmsg/sendmsg 32-bit compatability mode * tag 'io_uring-5.6-2020-02-28' of git://git.kernel.dk/linux-block: io_uring: fix 32-bit compatability with sendmsg/recvmsg io_uring: define and set show_fdinfo only if procfs is enabled io_uring: drop file set ref put/get on switch io_uring: import_single_range() returns 0/-ERROR io_uring: pick up link work on submit reference drop io-wq: ensure work->task_pid is cleared on init io-wq: remove spin-for-work optimization io_uring: fix poll_list race for SETUP_IOPOLL|SETUP_SQPOLL io_uring: fix personality idr leak io_uring: handle multiple personalities in link chains
| * | io_uring: fix 32-bit compatability with sendmsg/recvmsgJens Axboe2020-02-271-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We must set MSG_CMSG_COMPAT if we're in compatability mode, otherwise the iovec import for these commands will not do the right thing and fail the command with -EINVAL. Found by running the test suite compiled as 32-bit. Cc: stable@vger.kernel.org Fixes: aa1fa28fc73e ("io_uring: add support for recvmsg()") Fixes: 0fa03c624d8f ("io_uring: add support for sendmsg()") Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | io_uring: define and set show_fdinfo only if procfs is enabledTobias Klauser2020-02-271-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Follow the pattern used with other *_show_fdinfo functions and only define and use io_uring_show_fdinfo and its helper functions if CONFIG_PROC_FS is set. Fixes: 87ce955b24c9 ("io_uring: add ->show_fdinfo() for the io_uring file descriptor") Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | io_uring: drop file set ref put/get on switchJens Axboe2020-02-261-15/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dan reports that he triggered a warning on ring exit doing some testing: percpu ref (io_file_data_ref_zero) <= 0 (0) after switching to atomic WARNING: CPU: 3 PID: 0 at lib/percpu-refcount.c:160 percpu_ref_switch_to_atomic_rcu+0xe8/0xf0 Modules linked in: CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.6.0-rc3+ #5648 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 RIP: 0010:percpu_ref_switch_to_atomic_rcu+0xe8/0xf0 Code: e7 ff 55 e8 eb d2 80 3d bd 02 d2 00 00 75 8b 48 8b 55 d8 48 c7 c7 e8 70 e6 81 c6 05 a9 02 d2 00 01 48 8b 75 e8 e8 3a d0 c5 ff <0f> 0b e9 69 ff ff ff 90 55 48 89 fd 53 48 89 f3 48 83 ec 28 48 83 RSP: 0018:ffffc90000110ef8 EFLAGS: 00010292 RAX: 0000000000000045 RBX: 7fffffffffffffff RCX: 0000000000000000 RDX: 0000000000000045 RSI: ffffffff825be7a5 RDI: ffffffff825bc32c RBP: ffff8881b75eac38 R08: 000000042364b941 R09: 0000000000000045 R10: ffffffff825beb40 R11: ffffffff825be78a R12: 0000607e46005aa0 R13: ffff888107dcdd00 R14: 0000000000000000 R15: 0000000000000009 FS: 0000000000000000(0000) GS:ffff8881b9d80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f49e6a5ea20 CR3: 00000001b747c004 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> rcu_core+0x1e4/0x4d0 __do_softirq+0xdb/0x2f1 irq_exit+0xa0/0xb0 smp_apic_timer_interrupt+0x60/0x140 apic_timer_interrupt+0xf/0x20 </IRQ> RIP: 0010:default_idle+0x23/0x170 Code: ff eb ab cc cc cc cc 0f 1f 44 00 00 41 54 55 53 65 8b 2d 10 96 92 7e 0f 1f 44 00 00 e9 07 00 00 00 0f 00 2d 21 d0 51 00 fb f4 <65> 8b 2d f6 95 92 7e 0f 1f 44 00 00 5b 5d 41 5c c3 65 8b 05 e5 95 Turns out that this is due to percpu_ref_switch_to_atomic() only grabbing a reference to the percpu refcount if it's not already in atomic mode. io_uring drops a ref and re-gets it when switching back to percpu mode. We attempt to protect against this with the FFD_F_ATOMIC bit, but that isn't reliable. We don't actually need to juggle these refcounts between atomic and percpu switch, we can just do them when we've switched to atomic mode. This removes the need for FFD_F_ATOMIC, which wasn't reliable. Fixes: 05f3fb3c5397 ("io_uring: avoid ring quiesce for fixed file set unregister and update") Reported-by: Dan Melnic <dmm@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | io_uring: import_single_range() returns 0/-ERRORJens Axboe2020-02-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unlike the other core import helpers, import_single_range() returns 0 on success, not the length imported. This means that links that depend on the result of non-vec based IORING_OP_{READ,WRITE} that were added for 5.5 get errored when they should not be. Fixes: 3a6820f2bb8a ("io_uring: add non-vectored read/write commands") Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | io_uring: pick up link work on submit reference dropJens Axboe2020-02-261-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If work completes inline, then we should pick up a dependent link item in __io_queue_sqe() as well. If we don't do so, we're forced to go async with that item, which is suboptimal. This also fixes an issue with io_put_req_find_next(), which always looks up the next work item. That should only be done if we're dropping the last reference to the request, to prevent multiple lookups of the same work item. Outside of being a fix, this also enables a good cleanup series for 5.7, where we never have to pass 'nxt' around or into the work handlers. Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | io-wq: ensure work->task_pid is cleared on initJens Axboe2020-02-251-10/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We use ->task_pid for exit cancellation, but we need to ensure it's cleared to zero for io_req_work_grab_env() to do the right thing. Take a suggestion from Bart and clear the whole thing, just setting the function passed in. This makes it more future proof as well. Fixes: 36282881a795 ("io-wq: add io_wq_cancel_pid() to cancel based on a specific pid") Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | io-wq: remove spin-for-work optimizationJens Axboe2020-02-251-19/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Andres reports that buffered IO seems to suck up more cycles than we would like, and he narrowed it down to the fact that the io-wq workers will briefly spin for more work on completion of a work item. This was a win on the networking side, but apparently some other cases take a hit because of it. Remove the optimization to avoid burning more CPU than we have to for disk IO. Reported-by: Andres Freund <andres@anarazel.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | io_uring: fix poll_list race for SETUP_IOPOLL|SETUP_SQPOLLXiaoguang Wang2020-02-251-32/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After making ext4 support iopoll method: let ext4_file_operations's iopoll method be iomap_dio_iopoll(), we found fio can easily hang in fio_ioring_getevents() with below fio job: rm -f testfile; sync; sudo fio -name=fiotest -filename=testfile -iodepth=128 -thread -rw=write -ioengine=io_uring -hipri=1 -sqthread_poll=1 -direct=1 -bs=4k -size=10G -numjobs=8 -runtime=2000 -group_reporting with IORING_SETUP_SQPOLL and IORING_SETUP_IOPOLL enabled. There are two issues that results in this hang, one reason is that when IORING_SETUP_SQPOLL and IORING_SETUP_IOPOLL are enabled, fio does not use io_uring_enter to get completed events, it relies on kernel io_sq_thread to poll for completed events. Another reason is that there is a race: when io_submit_sqes() in io_sq_thread() submits a batch of sqes, variable 'inflight' will record the number of submitted reqs, then io_sq_thread will poll for reqs which have been added to poll_list. But note, if some previous reqs have been punted to io worker, these reqs will won't be in poll_list timely. io_sq_thread() will only poll for a part of previous submitted reqs, and then find poll_list is empty, reset variable 'inflight' to be zero. If app just waits these deferred reqs and does not wake up io_sq_thread again, then hang happens. For app that entirely relies on io_sq_thread to poll completed requests, let io_iopoll_req_issued() wake up io_sq_thread properly when adding new element to poll_list, and when io_sq_thread prepares to sleep, check whether poll_list is empty again, if not empty, continue to poll. Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | io_uring: fix personality idr leakJens Axboe2020-02-241-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | We somehow never free the idr, even though we init it for every ctx. Free it when the rest of the ring data is freed. Fixes: 071698e13ac6 ("io_uring: allow registering credentials") Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | io_uring: handle multiple personalities in link chainsJens Axboe2020-02-241-10/+15
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we have a chain of requests and they don't all use the same credentials, then the head of the chain will be issued with the credentails of the tail of the chain. Ensure __io_queue_sqe() overrides the credentials, if they are different. Once we do that, we can clean up the creds handling as well, by only having io_submit_sqe() do the lookup of a personality. It doesn't need to assign it, since __io_queue_sqe() now always does the right thing. Fixes: 75c6a03904e0 ("io_uring: support using a registered personality for commands") Reported-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | Merge tag 'zonefs-5.6-rc4' of ↵Linus Torvalds2020-02-282-4/+5
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs Pull zonefs fixes from Damien Le Moal: "Two fixes in here: - Revert the initial decision to silently ignore IOCB_NOWAIT for asynchronous direct IOs to sequential zone files. Instead, return an error to the user to signal that the feature is not supported (from Christoph) - A fix to zonefs Kconfig to select FS_IOMAP to avoid build failures if no other file system already selected this option (from Johannes)" * tag 'zonefs-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs: zonefs: select FS_IOMAP zonefs: fix IOCB_NOWAIT handling
| * zonefs: select FS_IOMAPJohannes Thumshirn2020-02-261-0/+1
| | | | | | | | | | | | | | | | Zonefs makes use of iomap internally, so it should also select iomap in Kconfig. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
| * zonefs: fix IOCB_NOWAIT handlingChristoph Hellwig2020-02-261-4/+4
| | | | | | | | | | | | | | | | | | | | IOCB_NOWAIT can't just be ignored as it breaks applications expecting it not to block. Just refuse the operation as applications must handle that (e.g. by falling back to a thread pool). Fixes: 8dcc1a9d90c1 ("fs: New zonefs file system") Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
* | Merge tag 'for-5.6-rc2-tag' of ↵Linus Torvalds2020-02-237-10/+44
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "These are fixes that were found during testing with help of error injection, plus some other stable material. There's a fixup to patch added to rc1 causing locking in wrong context warnings, tests found one more deadlock scenario. The patches are tagged for stable, two of them now in the queue but we'd like all three released at the same time. I'm not happy about fixes to fixes in such a fast succession during rcs, but I hope we found all the fallouts of commit 28553fa992cb ('Btrfs: fix race between shrinking truncate and fiemap')" * tag 'for-5.6-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: Btrfs: fix deadlock during fast fsync when logging prealloc extents beyond eof Btrfs: fix btrfs_wait_ordered_range() so that it waits for all ordered extents btrfs: fix bytes_may_use underflow in prealloc error condtition btrfs: handle logged extent failure properly btrfs: do not check delayed items are empty for single transaction cleanup btrfs: reset fs_root to NULL on error in open_ctree btrfs: destroy qgroup extent records on transaction abort
| * | Btrfs: fix deadlock during fast fsync when logging prealloc extents beyond eofFilipe Manana2020-02-211-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While logging the prealloc extents of an inode during a fast fsync we call btrfs_truncate_inode_items(), through btrfs_log_prealloc_extents(), while holding a read lock on a leaf of the inode's root (not the log root, the fs/subvol root), and then that function locks the file range in the inode's iotree. This can lead to a deadlock when: * the fsync is ranged * the file has prealloc extents beyond eof * writeback for a range different from the fsync range starts during the fsync * the size of the file is not sector size aligned Because when finishing an ordered extent we lock first a file range and then try to COW the fs/subvol tree to insert an extent item. The following diagram shows how the deadlock can happen. CPU 1 CPU 2 btrfs_sync_file() --> for range [0, 1MiB) --> inode has a size of 1MiB and has 1 prealloc extent beyond the i_size, starting at offset 4MiB flushes all delalloc for the range [0MiB, 1MiB) and waits for the respective ordered extents to complete --> before task at CPU 1 locks the inode, a write into file range [1MiB, 2MiB + 1KiB) is made --> i_size is updated to 2MiB + 1KiB --> writeback is started for that range, [1MiB, 2MiB + 4KiB) --> end offset rounded up to be sector size aligned btrfs_log_dentry_safe() btrfs_log_inode_parent() btrfs_log_inode() btrfs_log_changed_extents() btrfs_log_prealloc_extents() --> does a search on the inode's root --> holds a read lock on leaf X btrfs_finish_ordered_io() --> locks range [1MiB, 2MiB + 4KiB) --> end offset rounded up to be sector size aligned --> tries to cow leaf X, through insert_reserved_file_extent() --> already locked by the task at CPU 1 btrfs_truncate_inode_items() --> gets an i_size of 2MiB + 1KiB, which is not sector size aligned --> tries to lock file range [2MiB, (u64)-1) --> the start range is rounded down from 2MiB + 1K to 2MiB to be sector size aligned --> but the subrange [2MiB, 2MiB + 4KiB) is already locked by task at CPU 2 which is waiting to get a write lock on leaf X for which we are holding a read lock *** deadlock *** This results in a stack trace like the following, triggered by test case generic/561 from fstests: [ 2779.973608] INFO: task kworker/u8:6:247 blocked for more than 120 seconds. [ 2779.979536] Not tainted 5.6.0-rc2-btrfs-next-53 #1 [ 2779.984503] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 2779.990136] kworker/u8:6 D 0 247 2 0x80004000 [ 2779.990457] Workqueue: btrfs-endio-write btrfs_work_helper [btrfs] [ 2779.990466] Call Trace: [ 2779.990491] ? __schedule+0x384/0xa30 [ 2779.990521] schedule+0x33/0xe0 [ 2779.990616] btrfs_tree_read_lock+0x19e/0x2e0 [btrfs] [ 2779.990632] ? remove_wait_queue+0x60/0x60 [ 2779.990730] btrfs_read_lock_root_node+0x2f/0x40 [btrfs] [ 2779.990782] btrfs_search_slot+0x510/0x1000 [btrfs] [ 2779.990869] btrfs_lookup_file_extent+0x4a/0x70 [btrfs] [ 2779.990944] __btrfs_drop_extents+0x161/0x1060 [btrfs] [ 2779.990987] ? mark_held_locks+0x6d/0xc0 [ 2779.990994] ? __slab_alloc.isra.49+0x99/0x100 [ 2779.991060] ? insert_reserved_file_extent.constprop.19+0x64/0x300 [btrfs] [ 2779.991145] insert_reserved_file_extent.constprop.19+0x97/0x300 [btrfs] [ 2779.991222] ? start_transaction+0xdd/0x5c0 [btrfs] [ 2779.991291] btrfs_finish_ordered_io+0x4f4/0x840 [btrfs] [ 2779.991405] btrfs_work_helper+0xaa/0x720 [btrfs] [ 2779.991432] process_one_work+0x26d/0x6a0 [ 2779.991460] worker_thread+0x4f/0x3e0 [ 2779.991481] ? process_one_work+0x6a0/0x6a0 [ 2779.991489] kthread+0x103/0x140 [ 2779.991499] ? kthread_create_worker_on_cpu+0x70/0x70 [ 2779.991515] ret_from_fork+0x3a/0x50 (...) [ 2780.026211] INFO: task fsstress:17375 blocked for more than 120 seconds. [ 2780.027480] Not tainted 5.6.0-rc2-btrfs-next-53 #1 [ 2780.028482] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 2780.030035] fsstress D 0 17375 17373 0x00004000 [ 2780.030038] Call Trace: [ 2780.030044] ? __schedule+0x384/0xa30 [ 2780.030052] schedule+0x33/0xe0 [ 2780.030075] lock_extent_bits+0x20c/0x320 [btrfs] [ 2780.030094] ? btrfs_truncate_inode_items+0xf4/0x1150 [btrfs] [ 2780.030098] ? rcu_read_lock_sched_held+0x59/0xa0 [ 2780.030102] ? remove_wait_queue+0x60/0x60 [ 2780.030122] btrfs_truncate_inode_items+0x133/0x1150 [btrfs] [ 2780.030151] ? btrfs_set_path_blocking+0xb2/0x160 [btrfs] [ 2780.030165] ? btrfs_search_slot+0x379/0x1000 [btrfs] [ 2780.030195] btrfs_log_changed_extents.isra.8+0x841/0x93e [btrfs] [ 2780.030202] ? do_raw_spin_unlock+0x49/0xc0 [ 2780.030215] ? btrfs_get_num_csums+0x10/0x10 [btrfs] [ 2780.030239] btrfs_log_inode+0xf83/0x1124 [btrfs] [ 2780.030251] ? __mutex_unlock_slowpath+0x45/0x2a0 [ 2780.030275] btrfs_log_inode_parent+0x2a0/0xe40 [btrfs] [ 2780.030282] ? dget_parent+0xa1/0x370 [ 2780.030309] btrfs_log_dentry_safe+0x4a/0x70 [btrfs] [ 2780.030329] btrfs_sync_file+0x3f3/0x490 [btrfs] [ 2780.030339] do_fsync+0x38/0x60 [ 2780.030343] __x64_sys_fdatasync+0x13/0x20 [ 2780.030345] do_syscall_64+0x5c/0x280 [ 2780.030348] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 2780.030356] RIP: 0033:0x7f2d80f6d5f0 [ 2780.030361] Code: Bad RIP value. [ 2780.030362] RSP: 002b:00007ffdba3c8548 EFLAGS: 00000246 ORIG_RAX: 000000000000004b [ 2780.030364] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f2d80f6d5f0 [ 2780.030365] RDX: 00007ffdba3c84b0 RSI: 00007ffdba3c84b0 RDI: 0000000000000003 [ 2780.030367] RBP: 000000000000004a R08: 0000000000000001 R09: 00007ffdba3c855c [ 2780.030368] R10: 0000000000000078 R11: 0000000000000246 R12: 00000000000001f4 [ 2780.030369] R13: 0000000051eb851f R14: 00007ffdba3c85f0 R15: 0000557a49220d90 So fix this by making btrfs_truncate_inode_items() not lock the range in the inode's iotree when the target root is a log root, since it's not needed to lock the range for log roots as the protection from the inode's lock and log_mutex are all that's needed. Fixes: 28553fa992cb28 ("Btrfs: fix race between shrinking truncate and fiemap") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | Btrfs: fix btrfs_wait_ordered_range() so that it waits for all ordered extentsFilipe Manana2020-02-191-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In btrfs_wait_ordered_range() once we find an ordered extent that has finished with an error we exit the loop and don't wait for any other ordered extents that might be still in progress. All the users of btrfs_wait_ordered_range() expect that there are no more ordered extents in progress after that function returns. So past fixes such like the ones from the two following commits: ff612ba7849964 ("btrfs: fix panic during relocation after ENOSPC before writeback happens") 28aeeac1dd3080 ("Btrfs: fix panic when starting bg cache writeout after IO error") don't work when there are multiple ordered extents in the range. Fix that by making btrfs_wait_ordered_range() wait for all ordered extents even after it finds one that had an error. Link: https://github.com/kdave/btrfs-progs/issues/228#issuecomment-569777554 CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | btrfs: fix bytes_may_use underflow in prealloc error condtitionJosef Bacik2020-02-191-3/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I hit the following warning while running my error injection stress testing: WARNING: CPU: 3 PID: 1453 at fs/btrfs/space-info.h:108 btrfs_free_reserved_data_space_noquota+0xfd/0x160 [btrfs] RIP: 0010:btrfs_free_reserved_data_space_noquota+0xfd/0x160 [btrfs] Call Trace: btrfs_free_reserved_data_space+0x4f/0x70 [btrfs] __btrfs_prealloc_file_range+0x378/0x470 [btrfs] elfcorehdr_read+0x40/0x40 ? elfcorehdr_read+0x40/0x40 ? btrfs_commit_transaction+0xca/0xa50 [btrfs] ? dput+0xb4/0x2a0 ? btrfs_log_dentry_safe+0x55/0x70 [btrfs] ? btrfs_sync_file+0x30e/0x420 [btrfs] ? do_fsync+0x38/0x70 ? __x64_sys_fdatasync+0x13/0x20 ? do_syscall_64+0x5b/0x1b0 ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 This happens if we fail to insert our reserved file extent. At this point we've already converted our reservation from ->bytes_may_use to ->bytes_reserved. However once we break we will attempt to free everything from [cur_offset, end] from ->bytes_may_use, but our extent reservation will overlap part of this. Fix this problem by adding ins.offset (our extent allocation size) to cur_offset so we remove the actual remaining part from ->bytes_may_use. I validated this fix using my inject-error.py script python inject-error.py -o should_fail_bio -t cache_save_setup -t \ __btrfs_prealloc_file_range \ -t insert_reserved_file_extent.constprop.0 \ -r "-5" ./run-fsstress.sh where run-fsstress.sh simply mounts and runs fsstress on a disk. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | btrfs: handle logged extent failure properlyJosef Bacik2020-02-191-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we're allocating a logged extent we attempt to insert an extent record for the file extent directly. We increase space_info->bytes_reserved, because the extent entry addition will call btrfs_update_block_group(), which will convert the ->bytes_reserved to ->bytes_used. However if we fail at any point while inserting the extent entry we will bail and leave space on ->bytes_reserved, which will trigger a WARN_ON() on umount. Fix this by pinning the space if we fail to insert, which is what happens in every other failure case that involves adding the extent entry. CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | btrfs: do not check delayed items are empty for single transaction cleanupJosef Bacik2020-02-191-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | btrfs_assert_delayed_root_empty() will check if the delayed root is completely empty, but this is a filesystem-wide check. On cleanup we may have allowed other transactions to begin, for whatever reason, and thus the delayed root is not empty. So remove this check from cleanup_one_transation(). This however can stay in btrfs_cleanup_transaction(), because it checks only after all of the transactions have been properly cleaned up, and thus is valid. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | btrfs: reset fs_root to NULL on error in open_ctreeJosef Bacik2020-02-191-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While running my error injection script I hit a panic when we tried to clean up the fs_root when freeing the fs_root. This is because fs_info->fs_root == PTR_ERR(-EIO), which isn't great. Fix this by setting fs_info->fs_root = NULL; if we fail to read the root. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | btrfs: destroy qgroup extent records on transaction abortJeff Mahoney2020-02-194-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We clean up the delayed references when we abort a transaction but we leave the pending qgroup extent records behind, leaking memory. This patch destroys the extent records when we destroy the delayed refs and makes sure ensure they're gone before releasing the transaction. Fixes: 3368d001ba5d ("btrfs: qgroup: Record possible quota-related extent for qgroup.") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Jeff Mahoney <jeffm@suse.com> [ Rebased to latest upstream, remove to_qgroup() helper, use rbtree_postorder_for_each_entry_safe() wrapper ] Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | | Merge tag 'ext4_for_linus_stable' of ↵Linus Torvalds2020-02-2310-108/+256
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 fixes from Ted Ts'o: "More miscellaneous ext4 bug fixes (all stable fodder)" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: fix mount failure with quota configured as module jbd2: fix ocfs2 corrupt when clearing block group bits ext4: fix race between writepages and enabling EXT4_EXTENTS_FL ext4: rename s_journal_flag_rwsem to s_writepages_rwsem ext4: fix potential race between s_flex_groups online resizing and access ext4: fix potential race between s_group_info online resizing and access ext4: fix potential race between online resizing and write operations ext4: add cond_resched() to __ext4_find_entry() ext4: fix a data race in EXT4_I(inode)->i_disksize
| * | | ext4: fix mount failure with quota configured as moduleJan Kara2020-02-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When CONFIG_QFMT_V2 is configured as a module, the test in ext4_feature_set_ok() fails and so mount of filesystems with quota or project features fails. Fix the test to use IS_ENABLED macro which works properly even for modules. Link: https://lore.kernel.org/r/20200221100835.9332-1-jack@suse.cz Fixes: d65d87a07476 ("ext4: improve explanation of a mount failure caused by a misconfigured kernel") Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
| * | | jbd2: fix ocfs2 corrupt when clearing block group bitswangyan2020-02-221-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I found a NULL pointer dereference in ocfs2_block_group_clear_bits(). The running environment: kernel version: 4.19 A cluster with two nodes, 5 luns mounted on two nodes, and do some file operations like dd/fallocate/truncate/rm on every lun with storage network disconnection. The fallocate operation on dm-23-45 caused an null pointer dereference. The information of NULL pointer dereference as follows: [577992.878282] JBD2: Error -5 detected when updating journal superblock for dm-23-45. [577992.878290] Aborting journal on device dm-23-45. ... [577992.890778] JBD2: Error -5 detected when updating journal superblock for dm-24-46. [577992.890908] __journal_remove_journal_head: freeing b_committed_data [577992.890916] (fallocate,88392,52):ocfs2_extend_trans:474 ERROR: status = -30 [577992.890918] __journal_remove_journal_head: freeing b_committed_data [577992.890920] (fallocate,88392,52):ocfs2_rotate_tree_right:2500 ERROR: status = -30 [577992.890922] __journal_remove_journal_head: freeing b_committed_data [577992.890924] (fallocate,88392,52):ocfs2_do_insert_extent:4382 ERROR: status = -30 [577992.890928] (fallocate,88392,52):ocfs2_insert_extent:4842 ERROR: status = -30 [577992.890928] __journal_remove_journal_head: freeing b_committed_data [577992.890930] (fallocate,88392,52):ocfs2_add_clusters_in_btree:4947 ERROR: status = -30 [577992.890933] __journal_remove_journal_head: freeing b_committed_data [577992.890939] __journal_remove_journal_head: freeing b_committed_data [577992.890949] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020 [577992.890950] Mem abort info: [577992.890951] ESR = 0x96000004 [577992.890952] Exception class = DABT (current EL), IL = 32 bits [577992.890952] SET = 0, FnV = 0 [577992.890953] EA = 0, S1PTW = 0 [577992.890954] Data abort info: [577992.890955] ISV = 0, ISS = 0x00000004 [577992.890956] CM = 0, WnR = 0 [577992.890958] user pgtable: 4k pages, 48-bit VAs, pgdp = 00000000f8da07a9 [577992.890960] [0000000000000020] pgd=0000000000000000 [577992.890964] Internal error: Oops: 96000004 [#1] SMP [577992.890965] Process fallocate (pid: 88392, stack limit = 0x00000000013db2fd) [577992.890968] CPU: 52 PID: 88392 Comm: fallocate Kdump: loaded Tainted: G W OE 4.19.36 #1 [577992.890969] Hardware name: Huawei TaiShan 2280 V2/BC82AMDD, BIOS 0.98 08/25/2019 [577992.890971] pstate: 60400009 (nZCv daif +PAN -UAO) [577992.891054] pc : _ocfs2_free_suballoc_bits+0x63c/0x968 [ocfs2] [577992.891082] lr : _ocfs2_free_suballoc_bits+0x618/0x968 [ocfs2] [577992.891084] sp : ffff0000c8e2b810 [577992.891085] x29: ffff0000c8e2b820 x28: 0000000000000000 [577992.891087] x27: 00000000000006f3 x26: ffffa07957b02e70 [577992.891089] x25: ffff807c59d50000 x24: 00000000000006f2 [577992.891091] x23: 0000000000000001 x22: ffff807bd39abc30 [577992.891093] x21: ffff0000811d9000 x20: ffffa07535d6a000 [577992.891097] x19: ffff000001681638 x18: ffffffffffffffff [577992.891098] x17: 0000000000000000 x16: ffff000080a03df0 [577992.891100] x15: ffff0000811d9708 x14: 203d207375746174 [577992.891101] x13: 73203a524f525245 x12: 20373439343a6565 [577992.891103] x11: 0000000000000038 x10: 0101010101010101 [577992.891106] x9 : ffffa07c68a85d70 x8 : 7f7f7f7f7f7f7f7f [577992.891109] x7 : 0000000000000000 x6 : 0000000000000080 [577992.891110] x5 : 0000000000000000 x4 : 0000000000000002 [577992.891112] x3 : ffff000001713390 x2 : 2ff90f88b1c22f00 [577992.891114] x1 : ffff807bd39abc30 x0 : 0000000000000000 [577992.891116] Call trace: [577992.891139] _ocfs2_free_suballoc_bits+0x63c/0x968 [ocfs2] [577992.891162] _ocfs2_free_clusters+0x100/0x290 [ocfs2] [577992.891185] ocfs2_free_clusters+0x50/0x68 [ocfs2] [577992.891206] ocfs2_add_clusters_in_btree+0x198/0x5e0 [ocfs2] [577992.891227] ocfs2_add_inode_data+0x94/0xc8 [ocfs2] [577992.891248] ocfs2_extend_allocation+0x1bc/0x7a8 [ocfs2] [577992.891269] ocfs2_allocate_extents+0x14c/0x338 [ocfs2] [577992.891290] __ocfs2_change_file_space+0x3f8/0x610 [ocfs2] [577992.891309] ocfs2_fallocate+0xe4/0x128 [ocfs2] [577992.891316] vfs_fallocate+0x11c/0x250 [577992.891317] ksys_fallocate+0x54/0x88 [577992.891319] __arm64_sys_fallocate+0x28/0x38 [577992.891323] el0_svc_common+0x78/0x130 [577992.891325] el0_svc_handler+0x38/0x78 [577992.891327] el0_svc+0x8/0xc My analysis process as follows: ocfs2_fallocate __ocfs2_change_file_space ocfs2_allocate_extents ocfs2_extend_allocation ocfs2_add_inode_data ocfs2_add_clusters_in_btree ocfs2_insert_extent ocfs2_do_insert_extent ocfs2_rotate_tree_right ocfs2_extend_rotate_transaction ocfs2_extend_trans jbd2_journal_restart jbd2__journal_restart /* handle->h_transaction is NULL, * is_handle_aborted(handle) is true */ handle->h_transaction = NULL; start_this_handle return -EROFS; ocfs2_free_clusters _ocfs2_free_clusters _ocfs2_free_suballoc_bits ocfs2_block_group_clear_bits ocfs2_journal_access_gd __ocfs2_journal_access jbd2_journal_get_undo_access /* I think jbd2_write_access_granted() will * return true, because do_get_write_access() * will return -EROFS. */ if (jbd2_write_access_granted(...)) return 0; do_get_write_access /* handle->h_transaction is NULL, it will * return -EROFS here, so do_get_write_access() * was not called. */ if (is_handle_aborted(handle)) return -EROFS; /* bh2jh(group_bh) is NULL, caused NULL pointer dereference */ undo_bg = (struct ocfs2_group_desc *) bh2jh(group_bh)->b_committed_data; If handle->h_transaction == NULL, then jbd2_write_access_granted() does not really guarantee that journal_head will stay around, not even speaking of its b_committed_data. The bh2jh(group_bh) can be removed after ocfs2_journal_access_gd() and before call "bh2jh(group_bh)->b_committed_data". So, we should move is_handle_aborted() check from do_get_write_access() into jbd2_journal_get_undo_access() and jbd2_journal_get_write_access() before the call to jbd2_write_access_granted(). Link: https://lore.kernel.org/r/f72a623f-b3f1-381a-d91d-d22a1c83a336@huawei.com Signed-off-by: Yan Wang <wangyan122@huawei.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jun Piao <piaojun@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org
| * | | ext4: fix race between writepages and enabling EXT4_EXTENTS_FLEric Biggers2020-02-222-9/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If EXT4_EXTENTS_FL is set on an inode while ext4_writepages() is running on it, the following warning in ext4_add_complete_io() can be hit: WARNING: CPU: 1 PID: 0 at fs/ext4/page-io.c:234 ext4_put_io_end_defer+0xf0/0x120 Here's a minimal reproducer (not 100% reliable) (root isn't required): while true; do sync done & while true; do rm -f file touch file chattr -e file echo X >> file chattr +e file done The problem is that in ext4_writepages(), ext4_should_dioread_nolock() (which only returns true on extent-based files) is checked once to set the number of reserved journal credits, and also again later to select the flags for ext4_map_blocks() and copy the reserved journal handle to ext4_io_end::handle. But if EXT4_EXTENTS_FL is being concurrently set, the first check can see dioread_nolock disabled while the later one can see it enabled, causing the reserved handle to unexpectedly be NULL. Since changing EXT4_EXTENTS_FL is uncommon, and there may be other races related to doing so as well, fix this by synchronizing changing EXT4_EXTENTS_FL with ext4_writepages() via the existing s_writepages_rwsem (previously called s_journal_flag_rwsem). This was originally reported by syzbot without a reproducer at https://syzkaller.appspot.com/bug?extid=2202a584a00fffd19fbf, but now that dioread_nolock is the default I also started seeing this when running syzkaller locally. Link: https://lore.kernel.org/r/20200219183047.47417-3-ebiggers@kernel.org Reported-by: syzbot+2202a584a00fffd19fbf@syzkaller.appspotmail.com Fixes: 6b523df4fb5a ("ext4: use transaction reservation for extent conversion in ext4_end_io") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org
| * | | ext4: rename s_journal_flag_rwsem to s_writepages_rwsemEric Biggers2020-02-223-11/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In preparation for making s_journal_flag_rwsem synchronize ext4_writepages() with changes to both the EXTENTS and JOURNAL_DATA flags (rather than just JOURNAL_DATA as it does currently), rename it to s_writepages_rwsem. Link: https://lore.kernel.org/r/20200219183047.47417-2-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org
| * | | ext4: fix potential race between s_flex_groups online resizing and accessSuraj Jitindar Singh2020-02-225-37/+76
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During an online resize an array of s_flex_groups structures gets replaced so it can get enlarged. If there is a concurrent access to the array and this memory has been reused then this can lead to an invalid memory access. The s_flex_group array has been converted into an array of pointers rather than an array of structures. This is to ensure that the information contained in the structures cannot get out of sync during a resize due to an accessor updating the value in the old structure after it has been copied but before the array pointer is updated. Since the structures them- selves are no longer copied but only the pointers to them this case is mitigated. Link: https://bugzilla.kernel.org/show_bug.cgi?id=206443 Link: https://lore.kernel.org/r/20200221053458.730016-4-tytso@mit.edu Signed-off-by: Suraj Jitindar Singh <surajjs@amazon.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
| * | | ext4: fix potential race between s_group_info online resizing and accessSuraj Jitindar Singh2020-02-212-21/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During an online resize an array of pointers to s_group_info gets replaced so it can get enlarged. If there is a concurrent access to the array in ext4_get_group_info() and this memory has been reused then this can lead to an invalid memory access. Link: https://bugzilla.kernel.org/show_bug.cgi?id=206443 Link: https://lore.kernel.org/r/20200221053458.730016-3-tytso@mit.edu Signed-off-by: Suraj Jitindar Singh <surajjs@amazon.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Balbir Singh <sblbir@amazon.com> Cc: stable@kernel.org
| * | | ext4: fix potential race between online resizing and write operationsTheodore Ts'o2020-02-214-25/+97
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During an online resize an array of pointers to buffer heads gets replaced so it can get enlarged. If there is a racing block allocation or deallocation which uses the old array, and the old array has gotten reused this can lead to a GPF or some other random kernel memory getting modified. Link: https://bugzilla.kernel.org/show_bug.cgi?id=206443 Link: https://lore.kernel.org/r/20200221053458.730016-2-tytso@mit.edu Reported-by: Suraj Jitindar Singh <surajjs@amazon.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
| * | | ext4: add cond_resched() to __ext4_find_entry()Shijie Luo2020-02-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We tested a soft lockup problem in linux 4.19 which could also be found in linux 5.x. When dir inode takes up a large number of blocks, and if the directory is growing when we are searching, it's possible the restart branch could be called many times, and the do while loop could hold cpu a long time. Here is the call trace in linux 4.19. [ 473.756186] Call trace: [ 473.756196] dump_backtrace+0x0/0x198 [ 473.756199] show_stack+0x24/0x30 [ 473.756205] dump_stack+0xa4/0xcc [ 473.756210] watchdog_timer_fn+0x300/0x3e8 [ 473.756215] __hrtimer_run_queues+0x114/0x358 [ 473.756217] hrtimer_interrupt+0x104/0x2d8 [ 473.756222] arch_timer_handler_virt+0x38/0x58 [ 473.756226] handle_percpu_devid_irq+0x90/0x248 [ 473.756231] generic_handle_irq+0x34/0x50 [ 473.756234] __handle_domain_irq+0x68/0xc0 [ 473.756236] gic_handle_irq+0x6c/0x150 [ 473.756238] el1_irq+0xb8/0x140 [ 473.756286] ext4_es_lookup_extent+0xdc/0x258 [ext4] [ 473.756310] ext4_map_blocks+0x64/0x5c0 [ext4] [ 473.756333] ext4_getblk+0x6c/0x1d0 [ext4] [ 473.756356] ext4_bread_batch+0x7c/0x1f8 [ext4] [ 473.756379] ext4_find_entry+0x124/0x3f8 [ext4] [ 473.756402] ext4_lookup+0x8c/0x258 [ext4] [ 473.756407] __lookup_hash+0x8c/0xe8 [ 473.756411] filename_create+0xa0/0x170 [ 473.756413] do_mkdirat+0x6c/0x140 [ 473.756415] __arm64_sys_mkdirat+0x28/0x38 [ 473.756419] el0_svc_common+0x78/0x130 [ 473.756421] el0_svc_handler+0x38/0x78 [ 473.756423] el0_svc+0x8/0xc [ 485.755156] watchdog: BUG: soft lockup - CPU#2 stuck for 22s! [tmp:5149] Add cond_resched() to avoid soft lockup and to provide a better system responding. Link: https://lore.kernel.org/r/20200215080206.13293-1-luoshijie1@huawei.com Signed-off-by: Shijie Luo <luoshijie1@huawei.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: stable@kernel.org
| * | | ext4: fix a data race in EXT4_I(inode)->i_disksizeQian Cai2020-02-202-2/+2
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | EXT4_I(inode)->i_disksize could be accessed concurrently as noticed by KCSAN, BUG: KCSAN: data-race in ext4_write_end [ext4] / ext4_writepages [ext4] write to 0xffff91c6713b00f8 of 8 bytes by task 49268 on cpu 127: ext4_write_end+0x4e3/0x750 [ext4] ext4_update_i_disksize at fs/ext4/ext4.h:3032 (inlined by) ext4_update_inode_size at fs/ext4/ext4.h:3046 (inlined by) ext4_write_end at fs/ext4/inode.c:1287 generic_perform_write+0x208/0x2a0 ext4_buffered_write_iter+0x11f/0x210 [ext4] ext4_file_write_iter+0xce/0x9e0 [ext4] new_sync_write+0x29c/0x3b0 __vfs_write+0x92/0xa0 vfs_write+0x103/0x260 ksys_write+0x9d/0x130 __x64_sys_write+0x4c/0x60 do_syscall_64+0x91/0xb47 entry_SYSCALL_64_after_hwframe+0x49/0xbe read to 0xffff91c6713b00f8 of 8 bytes by task 24872 on cpu 37: ext4_writepages+0x10ac/0x1d00 [ext4] mpage_map_and_submit_extent at fs/ext4/inode.c:2468 (inlined by) ext4_writepages at fs/ext4/inode.c:2772 do_writepages+0x5e/0x130 __writeback_single_inode+0xeb/0xb20 writeback_sb_inodes+0x429/0x900 __writeback_inodes_wb+0xc4/0x150 wb_writeback+0x4bd/0x870 wb_workfn+0x6b4/0x960 process_one_work+0x54c/0xbe0 worker_thread+0x80/0x650 kthread+0x1e0/0x200 ret_from_fork+0x27/0x50 Reported by Kernel Concurrency Sanitizer on: CPU: 37 PID: 24872 Comm: kworker/u261:2 Tainted: G W O L 5.5.0-next-20200204+ #5 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019 Workqueue: writeback wb_workfn (flush-7:0) Since only the read is operating as lockless (outside of the "i_data_sem"), load tearing could introduce a logic bug. Fix it by adding READ_ONCE() for the read and WRITE_ONCE() for the write. Signed-off-by: Qian Cai <cai@lca.pw> Link: https://lore.kernel.org/r/1581085751-31793-1-git-send-email-cai@lca.pw Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
* | | Merge tag 'io_uring-5.6-2020-02-22' of git://git.kernel.dk/linux-blockLinus Torvalds2020-02-221-35/+30
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull io_uring fixes from Jens Axboe: "Here's a small collection of fixes that were queued up: - Remove unnecessary NULL check (Dan) - Missing io_req_cancelled() call in fallocate (Pavel) - Put the cleanup check for aux data in the right spot (Pavel) - Two fixes for SQPOLL (Stefano, Xiaoguang)" * tag 'io_uring-5.6-2020-02-22' of git://git.kernel.dk/linux-block: io_uring: fix __io_iopoll_check deadlock in io_sq_thread io_uring: prevent sq_thread from spinning when it should stop io_uring: fix use-after-free by io_cleanup_req() io_uring: remove unnecessary NULL checks io_uring: add missing io_req_cancelled()
| * | | io_uring: fix __io_iopoll_check deadlock in io_sq_threadXiaoguang Wang2020-02-221-18/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit a3a0e43fd770 ("io_uring: don't enter poll loop if we have CQEs pending"), if we already events pending, we won't enter poll loop. In case SETUP_IOPOLL and SETUP_SQPOLL are both enabled, if app has been terminated and don't reap pending events which are already in cq ring, and there are some reqs in poll_list, io_sq_thread will enter __io_iopoll_check(), and find pending events, then return, this loop will never have a chance to exit. I have seen this issue in fio stress tests, to fix this issue, let io_sq_thread call io_iopoll_getevents() with argument 'min' being zero, and remove __io_iopoll_check(). Fixes: a3a0e43fd770 ("io_uring: don't enter poll loop if we have CQEs pending") Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: prevent sq_thread from spinning when it should stopStefano Garzarella2020-02-211-12/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch drops 'cur_mm' before calling cond_resched(), to prevent the sq_thread from spinning even when the user process is finished. Before this patch, if the user process ended without closing the io_uring fd, the sq_thread continues to spin until the 'sq_thread_idle' timeout ends. In the worst case where the 'sq_thread_idle' parameter is bigger than INT_MAX, the sq_thread will spin forever. Fixes: 6c271ce2f1d5 ("io_uring: add submission polling") Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>