------------[ cut here ]------------ WARNING: CPU: 1 PID: 6701 at block/bio.c:513 bio_alloc_bioset+0xb98/0xf9c block/bio.c:-1 Modules linked in: CPU: 1 UID: 0 PID: 6701 Comm: kworker/u8:10 Not tainted 6.16.0-rc1-syzkaller-g39dfc971e42d #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: writeback wb_workfn (flush-bcachefs-13) pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : bio_alloc_bioset+0xb98/0xf9c block/bio.c:-1 lr : bio_alloc_bioset+0xb94/0xf9c block/bio.c:513 sp : ffff8000a1ce6ef0 x29: ffff8000a1ce6f10 x28: dfff800000000000 x27: 0000000000000000 x26: 0000000000000008 x25: 0000000000000000 x24: 0000000000000001 x23: 0000000000000cc0 x22: 0000000000000000 x21: 0000000000000000 x20: 0000000000000100 x19: ffff0001012c8948 x18: 00000000ffffffff x17: ffff80009331f000 x16: ffff800080520d04 x15: 0000000000000001 x14: 1fffffbff87ef1a8 x13: 0000000000000000 x12: 0000000000000000 x11: ffff7fbff87ef1a9 x10: 0000000000ff0100 x9 : 0000000000000000 x8 : ffff0000d5958000 x7 : ffff800080cb67f4 x6 : 0000000000000000 x5 : 0000000000000001 x4 : ffff0001012c8948 x3 : 0000000000000cc0 x2 : 0000000000000001 x1 : 0000000000000100 x0 : 0000000000000000 Call trace: bio_alloc_bioset+0xb98/0xf9c block/bio.c:-1 (P) bch2_writepage_io_alloc fs/bcachefs/fs-io-buffered.c:502 [inline] __bch2_writepage+0xdc8/0x1b3c fs/bcachefs/fs-io-buffered.c:636 write_cache_pages+0x6c/0x108 mm/page-writeback.c:2614 bch2_writepages+0xfc/0x294 fs/bcachefs/fs-io-buffered.c:666 do_writepages+0x270/0x468 mm/page-writeback.c:2636 __writeback_single_inode+0x15c/0x13e8 fs/fs-writeback.c:1680 writeback_sb_inodes+0x558/0xe38 fs/fs-writeback.c:1976 wb_writeback+0x3cc/0xd70 fs/fs-writeback.c:2156 wb_do_writeback fs/fs-writeback.c:2303 [inline] wb_workfn+0x338/0xdc0 fs/fs-writeback.c:2343 process_one_work+0x7e8/0x155c kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x958/0xed8 kernel/workqueue.c:3402 kthread+0x5fc/0x75c kernel/kthread.c:464 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:847 irq event stamp: 596688 hardirqs last enabled at (596687): [] lruvec_stat_mod_folio include/linux/vmstat.h:546 [inline] hardirqs last enabled at (596687): [] __folio_start_writeback+0x664/0x980 mm/page-writeback.c:3098 hardirqs last disabled at (596688): [] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:511 softirqs last enabled at (596544): [] spin_unlock_bh include/linux/spinlock.h:396 [inline] softirqs last enabled at (596544): [] batadv_nc_purge_paths+0x2f4/0x37c net/batman-adv/network-coding.c:471 softirqs last disabled at (596542): [] spin_lock_bh include/linux/spinlock.h:356 [inline] softirqs last disabled at (596542): [] batadv_nc_purge_paths+0xd0/0x37c net/batman-adv/network-coding.c:442 ---[ end trace 0000000000000000 ]--- Unable to handle kernel paging request at virtual address fffffffffffffc98 KASAN: maybe wild-memory-access in range [0x0003ffffffffe4c0-0x0003ffffffffe4c7] Mem abort info: ESR = 0x0000000096000046 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x06: level 2 translation fault Data abort info: ISV = 0, ISS = 0x00000046, ISS2 = 0x00000000 CM = 0, WnR = 1, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 swapper pgtable: 4k pages, 48-bit VAs, pgdp=000000020730e000 [fffffffffffffc98] pgd=0000000000000000, p4d=000000020b076403, pud=000000020b077403, pmd=0000000000000000 Internal error: Oops: 0000000096000046 [#1] SMP Modules linked in: CPU: 1 UID: 0 PID: 6701 Comm: kworker/u8:10 Tainted: G W 6.16.0-rc1-syzkaller-g39dfc971e42d #0 PREEMPT Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: writeback wb_workfn (flush-bcachefs-13) pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : bch2_writepage_io_alloc fs/bcachefs/fs-io-buffered.c:508 [inline] pc : __bch2_writepage+0xe0c/0x1b3c fs/bcachefs/fs-io-buffered.c:636 lr : bch2_writepage_io_alloc fs/bcachefs/fs-io-buffered.c:502 [inline] lr : __bch2_writepage+0xdc8/0x1b3c fs/bcachefs/fs-io-buffered.c:636 sp : ffff8000a1ce6f70 x29: ffff8000a1ce70f0 x28: 0000000000000008 x27: 1fffe00019419200 x26: 0000000000000008 x25: ffff0000ca0c9000 x24: ffff0000f9006840 x23: 0000000000000008 x22: ffff0000ca0c901a x21: ffff0000ca0c9008 x20: dfff800000000000 x19: fffffffffffffc98 x18: 00000000ffffffff x17: ffff80009331f000 x16: ffff800080520d04 x15: 0000000000000001 x14: 1fffffbff87ef1a8 x13: 0000000000000000 x12: 0000000000000000 x11: ffff7fbff87ef1a9 x10: 0000000000ff0100 x9 : ffff000100cca5f8 x8 : 1fffe00019419201 x7 : ffff800080cb67f4 x6 : 0000000000000000 x5 : 0000000000000001 x4 : ffff0001012c8948 x3 : 0000000000000cc0 x2 : 0000000000000001 x1 : 0000000000000100 x0 : 0000000000000000 Call trace: bch2_writepage_io_alloc fs/bcachefs/fs-io-buffered.c:510 [inline] (P) __bch2_writepage+0xe0c/0x1b3c fs/bcachefs/fs-io-buffered.c:636 (P) write_cache_pages+0x6c/0x108 mm/page-writeback.c:2614 bch2_writepages+0xfc/0x294 fs/bcachefs/fs-io-buffered.c:666 do_writepages+0x270/0x468 mm/page-writeback.c:2636 __writeback_single_inode+0x15c/0x13e8 fs/fs-writeback.c:1680 writeback_sb_inodes+0x558/0xe38 fs/fs-writeback.c:1976 wb_writeback+0x3cc/0xd70 fs/fs-writeback.c:2156 wb_do_writeback fs/fs-writeback.c:2303 [inline] wb_workfn+0x338/0xdc0 fs/fs-writeback.c:2343 process_one_work+0x7e8/0x155c kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x958/0xed8 kernel/workqueue.c:3402 kthread+0x5fc/0x75c kernel/kthread.c:464 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:847 Code: aa1303e0 978ba352 f85c83a9 d343fea8 (f9000269) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: aa1303e0 mov x0, x19 4: 978ba352 bl 0xfffffffffe2e8d4c 8: f85c83a9 ldur x9, [x29, #-56] c: d343fea8 lsr x8, x21, #3 * 10: f9000269 str x9, [x19] <-- trapping instruction