Jan Kara <jack@xxxxxxx> 于2021年4月12日周一 下午5:02写道： > > Hello, > > On Sun 11-04-21 11:42:05, Hao Sun wrote: > > Since the last KCSAN report[1], I found two more KCSAN reports that > > Syzbot had not reported. > > Not sure if they are valid bugs, I hope the stack information in > > reports can help you locate the problem. > > Kernel config can be found in the attachment. > > Do we have symbolic decoding of the traces below? Because involved > functions are really big so it's difficult to guess what KCSAN is > complaining about... At least I wasn't able to guess it after looking into > the stacktraces for a while. > Sorry, the log processing module of Fuzzer still has some logic bugs, only some of the symbolized reports are stored in the disk. Interestingly, however, the read-write end that causes data racing in both reports are in the same location (fs/jbd2/commit.c:443), and this information should help locate the problem. Partial symbolized report 1: ================================================================== BUG: KCSAN: data-race in ext4_mark_iloc_dirty / jbd2_journal_commit_transaction read-write to 0xffff88804451d800 of 8 bytes by task 4821 on cpu 1: jbd2_journal_commit_transaction+0x222/0x3200 fs/jbd2/commit.c:443 kjournald2+0x253/0x470 fs/jbd2/journal.c:213 kthread+0x1f0/0x220 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Partial symbolized report 2: ================================================================== BUG: KCSAN: data-race in __ext4_handle_dirty_metadata / jbd2_journal_commit_transaction read-write to 0xffff88800e142800 of 8 bytes by task 4823 on cpu 0: jbd2_journal_commit_transaction+0x222/0x3200 fs/jbd2/commit.c:443 kjournald2+0x253/0x470 fs/jbd2/journal.c:213 kthread+0x1f0/0x220 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 > > > > > Here is the detailed information: > > commit: 3b9cdafb5358eb9f3790de2f728f765fef100731 > > version: linux 5.11 > > git tree: upstream > > > > Report-1 > > ================================================================== > > BUG: KCSAN: data-race in ext4_mark_iloc_dirty / jbd2_journal_commit_transaction > > > > read-write to 0xffff88804451d800 of 8 bytes by task 4821 on cpu 1: > > jbd2_journal_commit_transaction+0x222/0x3200 > > kjournald2+0x253/0x470 > > kthread+0x1f0/0x220 > > ret_from_fork+0x1f/0x30 > > > > read to 0xffff88804451d800 of 8 bytes by task 8418 on cpu 0: > > ext4_mark_iloc_dirty+0x14ec/0x16e0 > > __ext4_mark_inode_dirty+0x4d2/0x5d0 > > ext4_evict_inode+0xb9f/0xed0 > > evict+0x1a6/0x410 > > iput+0x3fc/0x510 > > do_unlinkat+0x2c9/0x4d0 > > __x64_sys_unlink+0x2c/0x30 > > do_syscall_64+0x39/0x80 > > entry_SYSCALL_64_after_hwframe+0x44/0xae > > > > Report-2 > > ================================================================== > > BUG: KCSAN: data-race in __ext4_handle_dirty_metadata / > > jbd2_journal_commit_transaction > > > > read-write to 0xffff88800e142800 of 8 bytes by task 4823 on cpu 0: > > jbd2_journal_commit_transaction+0x222/0x3200 > > kjournald2+0x253/0x470 > > kthread+0x1f0/0x220 > > ret_from_fork+0x1f/0x30 > > > > read to 0xffff88800e142800 of 8 bytes by task 7925 on cpu 1: > > __ext4_handle_dirty_metadata+0x11a/0x590 > > ext4_mark_iloc_dirty+0x12dd/0x16e0 > > __ext4_mark_inode_dirty+0x4d2/0x5d0 > > ext4_dirty_inode+0x86/0xa0 > > __mark_inode_dirty+0x70/0x6b0 > > file_update_time+0x3ab/0x3f0 > > file_modified+0x62/0x80 > > ext4_buffered_write_iter+0x1f9/0x3d0 > > ext4_file_write_iter+0x45e/0x10d0 > > vfs_write+0x6db/0x7c0 > > ksys_write+0xce/0x180 > > __x64_sys_write+0x3e/0x50 > > do_syscall_64+0x39/0x80 > > entry_SYSCALL_64_after_hwframe+0x44/0xae > > > > > > [1] https://lore.kernel.org/lkml/CACkBjsZW5Sp4jB51+C5mrMssgq73x8iEko_EV6CTXVvtVa7KPQ@xxxxxxxxxxxxxx/ > > > -- > Jan Kara <jack@xxxxxxxx> > SUSE Labs, CR
