md/raid:md4: not clean -- starting background reconstruction ------------[ cut here ]------------ WARNING: mm/page_alloc.c:5340 at alloc_order_allowed mm/page_alloc.c:5340 [inline], CPU#0: syz.4.688/9395 WARNING: mm/page_alloc.c:5340 at __alloc_frozen_pages_noprof+0xe4/0x578 mm/page_alloc.c:5397, CPU#0: syz.4.688/9395 Modules linked in: CPU: 0 UID: 0 PID: 9395 Comm: syz.4.688 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026 pstate: 23400005 (nzCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : alloc_order_allowed mm/page_alloc.c:5340 [inline] pc : __alloc_frozen_pages_noprof+0xe4/0x578 mm/page_alloc.c:5397 lr : __alloc_frozen_pages_noprof+0xa8/0x578 mm/page_alloc.c:5388 sp : ffff8000985a72e0 x29: ffff8000985a73a0 x28: ffff0000c2462018 x27: ffff8000985a7300 x26: 1ffff00011e9d6ec x25: dfff800000000000 x24: ffff7000130b4e60 x23: 0000000000000000 x22: 0000000000000000 x21: 0000000000040dc0 x20: 0000000000000000 x19: 0000000000000034 x18: ffff80011b876000 x17: ffff0001a4fd3e07 x16: ffff0000cf0fd894 x15: 000000000000000f x14: 0000000000000017 x13: 0000000000000005 x12: 0000000000000000 x11: 0000000000000000 x10: ffff7000130b4e69 x9 : 0000000000000001 x8 : ffff80008ae12000 x7 : 0000000000000000 x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000020 x2 : 0000000000000008 x1 : 0000000000000000 x0 : ffff8000985a7320 Call trace: alloc_order_allowed mm/page_alloc.c:5340 [inline] (P) __alloc_frozen_pages_noprof+0xe4/0x578 mm/page_alloc.c:5397 (P) alloc_pages_mpol+0x1fc/0x3d0 mm/mempolicy.c:2486 alloc_frozen_pages_noprof+0xc4/0x10c mm/mempolicy.c:2557 ___kmalloc_large_node+0x74/0x158 mm/slub.c:5353 __kmalloc_large_node_noprof+0x2c/0x8c mm/slub.c:5385 __do_kmalloc_node mm/slub.c:5402 [inline] __kmalloc_noprof+0x3f0/0x6c8 mm/slub.c:5439 _kmalloc_noprof include/linux/slab.h:995 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] setup_conf+0x9e4/0x1f38 drivers/md/raid5.c:7732 raid5_run+0x670/0x1b68 drivers/md/raid5.c:8129 md_run+0xb10/0x19e8 drivers/md/md.c:6779 do_md_run+0x4c/0x4e4 drivers/md/md.c:6880 md_ioctl+0x1bf8/0x23d4 drivers/md/md.c:8515 blkdev_ioctl+0x574/0x904 block/ioctl.c:798 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __arm64_sys_ioctl+0x154/0x1cc fs/ioctl.c:583 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x60/0x1d8 arch/arm64/kernel/entry-common.c:796 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:815 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606 irq event stamp: 812 hardirqs last enabled at (811): [] seqcount_lockdep_reader_access+0x68/0xcc include/linux/seqlock.h:75 hardirqs last disabled at (812): [] el1_brk64+0x20/0x54 arch/arm64/kernel/entry-common.c:483 softirqs last enabled at (766): [] softirq_handle_end kernel/softirq.c:491 [inline] softirqs last enabled at (766): [] handle_softirqs+0xb2c/0xcbc kernel/softirq.c:673 softirqs last disabled at (601): [] __do_softirq+0x14/0x20 kernel/softirq.c:679 ---[ end trace 0000000000000000 ]--- Unable to handle kernel paging request at virtual address dfff800000000005 KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] Mem abort info: ESR = 0x0000000096000005 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x05: level 1 translation fault Data abort info: ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0 [dfff800000000005] address between user and kernel address ranges Internal error: Oops: 0000000096000005 [#1] SMP Modules linked in: CPU: 0 UID: 0 PID: 9395 Comm: syz.4.688 Tainted: G W syzkaller #0 PREEMPT Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026 pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : generic_test_bit include/asm-generic/bitops/generic-non-atomic.h:128 [inline] pc : raid5_has_ppl drivers/md/raid5-log.h:54 [inline] pc : log_exit drivers/md/raid5-log.h:128 [inline] pc : free_conf+0x88/0x540 drivers/md/raid5.c:7549 lr : free_conf+0x34/0x540 drivers/md/raid5.c:7546 sp : ffff8000985a7550 x29: ffff8000985a7560 x28: ffff0000c2462018 x27: ffff7000130b4ecc x26: ffff0000d2fc0000 x25: 1fffe0001a5f8044 x24: ffff0000d2fc0000 x23: dfff800000000000 x22: 00000000fffffff4 x21: ffff0000d2fc0660 x20: 0000000000000028 x19: ffff0000d2fc0000 x18: ffff80011b876000 x17: ffff0001a4fd3e07 x16: ffff0000cf0fd894 x15: 000000000000000f x14: 0000000000000017 x13: 0000000000000005 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000000003 x9 : 0000000000000000 x8 : 0000000000000005 x7 : 0000000000000000 x6 : 0000000000000000 x5 : 00000000ffffffff x4 : 0000000000000dc0 x3 : 0000000000000000 x2 : ffffffffffffffff x1 : ffff0000cf0fd880 x0 : 0000000000000000 Call trace: generic_test_bit include/asm-generic/bitops/generic-non-atomic.h:128 [inline] (P) raid5_has_ppl drivers/md/raid5-log.h:54 [inline] (P) log_exit drivers/md/raid5-log.h:128 [inline] (P) free_conf+0x88/0x540 drivers/md/raid5.c:7549 (P) setup_conf+0xb0c/0x1f38 drivers/md/raid5.c:7885 raid5_run+0x670/0x1b68 drivers/md/raid5.c:8129 md_run+0xb10/0x19e8 drivers/md/md.c:6779 do_md_run+0x4c/0x4e4 drivers/md/md.c:6880 md_ioctl+0x1bf8/0x23d4 drivers/md/md.c:8515 blkdev_ioctl+0x574/0x904 block/ioctl.c:798 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __arm64_sys_ioctl+0x154/0x1cc fs/ioctl.c:583 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x60/0x1d8 arch/arm64/kernel/entry-common.c:796 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:815 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:606 Code: 97315314 f9400288 9100a114 d343fe88 (38776908) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 97315314 bl 0xfffffffffcc54c50 4: f9400288 ldr x8, [x20] 8: 9100a114 add x20, x8, #0x28 c: d343fe88 lsr x8, x20, #3 * 10: 38776908 ldrb w8, [x8, x23] <-- trapping instruction