================================================================== BUG: KCSAN: data-race in pcpu_alloc / pcpu_block_update_hint_alloc read-write to 0xffffffff8842949c of 4 bytes by task 24407 on cpu 0: pcpu_update_empty_pages mm/percpu.c:602 [inline] pcpu_block_update_hint_alloc+0x5db/0x6a0 mm/percpu.c:923 pcpu_alloc_area+0x49f/0x4d0 mm/percpu.c:1258 pcpu_alloc+0x4b3/0x10d0 mm/percpu.c:1808 __alloc_percpu_gfp+0x26/0x30 mm/percpu.c:1930 bpf_map_alloc_percpu+0xab/0x200 kernel/bpf/syscall.c:466 prealloc_init+0x19f/0x470 kernel/bpf/hashtab.c:341 htab_map_alloc+0x637/0x8f0 kernel/bpf/hashtab.c:576 map_create+0x83c/0xb90 kernel/bpf/syscall.c:1333 __sys_bpf+0x667/0x7a0 kernel/bpf/syscall.c:5669 __do_sys_bpf kernel/bpf/syscall.c:5794 [inline] __se_sys_bpf kernel/bpf/syscall.c:5792 [inline] __x64_sys_bpf+0x43/0x50 kernel/bpf/syscall.c:5792 x64_sys_call+0x86c/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffffffff8842949c of 4 bytes by task 24409 on cpu 1: pcpu_alloc+0x9aa/0x10d0 mm/percpu.c:1868 __alloc_percpu_gfp+0x26/0x30 mm/percpu.c:1930 bpf_map_alloc_percpu+0xab/0x200 kernel/bpf/syscall.c:466 prealloc_init+0x19f/0x470 kernel/bpf/hashtab.c:341 htab_map_alloc+0x637/0x8f0 kernel/bpf/hashtab.c:576 map_create+0x83c/0xb90 kernel/bpf/syscall.c:1333 __sys_bpf+0x667/0x7a0 kernel/bpf/syscall.c:5669 __do_sys_bpf kernel/bpf/syscall.c:5794 [inline] __se_sys_bpf kernel/bpf/syscall.c:5792 [inline] __x64_sys_bpf+0x43/0x50 kernel/bpf/syscall.c:5792 x64_sys_call+0x86c/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000002 -> 0xfffffffa Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 24409 Comm: syz-executor.4 Not tainted 6.9.0-syzkaller-08414-g7ee332c9f12b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 ==================================================================