================================================================== BUG: KCSAN: data-race in start_this_handle / start_this_handle write to 0xffff888144333870 of 8 bytes by task 21084 on cpu 0: jbd2_get_transaction syzkaller/managers/upstream-kcsan-gce/kernel/fs/jbd2/transaction.c:125 [inline] start_this_handle+0xceb/0x1010 syzkaller/managers/upstream-kcsan-gce/kernel/fs/jbd2/transaction.c:400 jbd2__journal_start+0x1fc/0x3f0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/jbd2/transaction.c:503 __ext4_journal_start_sb+0x154/0x310 syzkaller/managers/upstream-kcsan-gce/kernel/fs/ext4/ext4_jbd2.c:105 __ext4_journal_start syzkaller/managers/upstream-kcsan-gce/kernel/fs/ext4/ext4_jbd2.h:320 [inline] ext4_da_write_begin+0x46e/0xaa0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/ext4/inode.c:2997 generic_perform_write+0x196/0x3a0 syzkaller/managers/upstream-kcsan-gce/kernel/mm/filemap.c:3412 ext4_buffered_write_iter+0x2e5/0x3e0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/ext4/file.c:270 ext4_file_write_iter+0x47a/0x1060 syzkaller/managers/upstream-kcsan-gce/kernel/fs/ext4/file.c:503 call_write_iter syzkaller/managers/upstream-kcsan-gce/kernel/./include/linux/fs.h:1901 [inline] do_iter_readv_writev+0x2cb/0x360 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:740 do_iter_write+0x112/0x4c0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:866 vfs_iter_write+0x4c/0x70 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:907 iter_file_splice_write+0x41a/0x770 syzkaller/managers/upstream-kcsan-gce/kernel/fs/splice.c:686 do_splice_from syzkaller/managers/upstream-kcsan-gce/kernel/fs/splice.c:764 [inline] direct_splice_actor+0x80/0xa0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/splice.c:933 splice_direct_to_actor+0x345/0x650 syzkaller/managers/upstream-kcsan-gce/kernel/fs/splice.c:888 do_splice_direct+0xf5/0x170 syzkaller/managers/upstream-kcsan-gce/kernel/fs/splice.c:976 do_sendfile+0x5e0/0xcf0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:1257 __do_sys_sendfile64 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:1312 [inline] __se_sys_sendfile64 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:1304 [inline] __x64_sys_sendfile64+0xa9/0x130 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:1304 do_syscall_64+0x39/0x80 syzkaller/managers/upstream-kcsan-gce/kernel/arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff888144333870 of 8 bytes by task 21050 on cpu 1: start_this_handle+0x1c1/0x1010 syzkaller/managers/upstream-kcsan-gce/kernel/fs/jbd2/transaction.c:352 jbd2__journal_start+0x1fc/0x3f0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/jbd2/transaction.c:503 __ext4_journal_start_sb+0x154/0x310 syzkaller/managers/upstream-kcsan-gce/kernel/fs/ext4/ext4_jbd2.c:105 __ext4_journal_start syzkaller/managers/upstream-kcsan-gce/kernel/fs/ext4/ext4_jbd2.h:320 [inline] ext4_dirty_inode+0x78/0xc0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/ext4/inode.c:5951 __mark_inode_dirty+0x72/0x6b0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/fs-writeback.c:2262 generic_update_time syzkaller/managers/upstream-kcsan-gce/kernel/fs/inode.c:1763 [inline] update_time syzkaller/managers/upstream-kcsan-gce/kernel/fs/inode.c:1776 [inline] file_update_time+0x3ac/0x3f0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/inode.c:1991 file_modified+0x62/0x80 syzkaller/managers/upstream-kcsan-gce/kernel/fs/inode.c:2014 ext4_write_checks syzkaller/managers/upstream-kcsan-gce/kernel/fs/ext4/file.c:248 [inline] ext4_buffered_write_iter+0x1f9/0x3e0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/ext4/file.c:265 ext4_file_write_iter+0x47a/0x1060 syzkaller/managers/upstream-kcsan-gce/kernel/fs/ext4/file.c:503 call_write_iter syzkaller/managers/upstream-kcsan-gce/kernel/./include/linux/fs.h:1901 [inline] do_iter_readv_writev+0x2cb/0x360 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:740 do_iter_write+0x112/0x4c0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:866 vfs_iter_write+0x4c/0x70 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:907 iter_file_splice_write+0x41a/0x770 syzkaller/managers/upstream-kcsan-gce/kernel/fs/splice.c:686 do_splice_from syzkaller/managers/upstream-kcsan-gce/kernel/fs/splice.c:764 [inline] direct_splice_actor+0x80/0xa0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/splice.c:933 splice_direct_to_actor+0x345/0x650 syzkaller/managers/upstream-kcsan-gce/kernel/fs/splice.c:888 do_splice_direct+0xf5/0x170 syzkaller/managers/upstream-kcsan-gce/kernel/fs/splice.c:976 do_sendfile+0x5e0/0xcf0 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:1257 __do_sys_sendfile64 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:1312 [inline] __se_sys_sendfile64 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:1304 [inline] __x64_sys_sendfile64+0xa9/0x130 syzkaller/managers/upstream-kcsan-gce/kernel/fs/read_write.c:1304 do_syscall_64+0x39/0x80 syzkaller/managers/upstream-kcsan-gce/kernel/arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 21050 Comm: syz-executor.1 Not tainted 5.11.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================