================================================================== BUG: KCSAN: data-race in mb_free_blocks / mb_update_avg_fragment_size write to 0xffff8881010da614 of 4 bytes by task 17854 on cpu 0: mb_free_blocks+0x156/0xb40 fs/ext4/mballoc.c:1802 ext4_free_blocks+0x14ea/0x1c20 fs/ext4/mballoc.c:6061 ext4_remove_blocks+0x61a/0x800 fs/ext4/extents.c:2506 ext4_ext_rm_leaf+0x684/0xd40 fs/ext4/extents.c:2672 ext4_ext_remove_space+0x8f6/0x12b0 fs/ext4/extents.c:2920 ext4_ext_truncate+0xfe/0x170 fs/ext4/extents.c:4382 ext4_truncate+0x76e/0xa80 fs/ext4/inode.c:4268 ext4_setattr+0xb00/0xef0 fs/ext4/inode.c:5521 notify_change+0x8a3/0xac0 fs/attr.c:410 do_truncate+0xf7/0x140 fs/open.c:64 handle_truncate fs/namei.c:3084 [inline] do_open fs/namei.c:3432 [inline] path_openat+0x1925/0x1ec0 fs/namei.c:3561 do_filp_open+0x105/0x220 fs/namei.c:3588 do_sys_openat2+0xb5/0x2b0 fs/open.c:1200 do_sys_open fs/open.c:1216 [inline] __do_sys_openat fs/open.c:1232 [inline] __se_sys_openat fs/open.c:1227 [inline] __x64_sys_openat+0xef/0x110 fs/open.c:1227 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff8881010da614 of 4 bytes by task 17858 on cpu 1: ext4_mb_avg_fragment_size_cmp fs/ext4/mballoc.c:839 [inline] ext4_mb_rb_insert fs/ext4/mballoc.c:815 [inline] mb_update_avg_fragment_size+0x184/0x260 fs/ext4/mballoc.c:863 mb_mark_used+0xae0/0xc50 fs/ext4/mballoc.c:1998 ext4_mb_use_best_found+0x102/0x320 fs/ext4/mballoc.c:2019 ext4_mb_simple_scan_group+0x253/0x3a0 fs/ext4/mballoc.c:2297 ext4_mb_regular_allocator+0x1984/0x2530 fs/ext4/mballoc.c:2773 ext4_mb_new_blocks+0x792/0x1fc0 fs/ext4/mballoc.c:5586 ext4_ext_map_blocks+0x15ed/0x1ff0 fs/ext4/extents.c:4250 ext4_map_blocks+0x71e/0xf00 fs/ext4/inode.c:637 ext4_alloc_file_blocks+0x281/0x730 fs/ext4/extents.c:4437 ext4_fallocate+0x2a7/0x4d0 fs/ext4/extents.c:4718 vfs_fallocate+0x459/0x6a0 fs/open.c:307 do_vfs_ioctl+0x13c6/0x14c0 fs/ioctl.c:853 __do_sys_ioctl fs/ioctl.c:872 [inline] __se_sys_ioctl+0x83/0x140 fs/ioctl.c:860 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x0000181f -> 0x0000281f Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 17858 Comm: syz-executor.3 Tainted: G W 5.15.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================