================================================================== BUG: KCSAN: data-race in compaction_alloc / compaction_alloc write to 0xffff88813fffbc08 of 8 bytes by task 26701 on cpu 1: update_pageblock_skip mm/compaction.c:460 [inline] isolate_freepages mm/compaction.c:1572 [inline] compaction_alloc+0x1286/0x1520 mm/compaction.c:1625 unmap_and_move+0x113/0x690 mm/migrate.c:1190 migrate_pages+0x2f7/0xfa0 mm/migrate.c:1466 compact_zone+0x1596/0x1d60 mm/compaction.c:2358 compact_node+0xe4/0x1e0 mm/compaction.c:2634 compact_nodes mm/compaction.c:2650 [inline] sysctl_compaction_handler+0x47/0x90 mm/compaction.c:2671 proc_sys_call_handler+0x3d3/0x520 fs/proc/proc_sysctl.c:591 proc_sys_write+0x1e/0x30 fs/proc/proc_sysctl.c:617 call_write_iter include/linux/fs.h:1901 [inline] new_sync_write fs/read_write.c:518 [inline] vfs_write+0x6f0/0x7e0 fs/read_write.c:605 ksys_write+0xce/0x180 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:667 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff88813fffbc08 of 8 bytes by task 26702 on cpu 0: update_pageblock_skip mm/compaction.c:459 [inline] isolate_freepages mm/compaction.c:1572 [inline] compaction_alloc+0x1262/0x1520 mm/compaction.c:1625 unmap_and_move+0x113/0x690 mm/migrate.c:1190 migrate_pages+0x2f7/0xfa0 mm/migrate.c:1466 compact_zone+0x1596/0x1d60 mm/compaction.c:2358 compact_node+0xe4/0x1e0 mm/compaction.c:2634 compact_nodes mm/compaction.c:2650 [inline] sysctl_compaction_handler+0x47/0x90 mm/compaction.c:2671 proc_sys_call_handler+0x3d3/0x520 fs/proc/proc_sysctl.c:591 proc_sys_write+0x1e/0x30 fs/proc/proc_sysctl.c:617 call_write_iter include/linux/fs.h:1901 [inline] new_sync_write fs/read_write.c:518 [inline] vfs_write+0x6f0/0x7e0 fs/read_write.c:605 ksys_write+0xce/0x180 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:667 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 26702 Comm: syz-executor.1 Not tainted 5.11.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================