Hello, syzbot found the following issue on: HEAD commit: 1621b6eaebf7 Merge branch 'for-next/fixes' into for-kernelci git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=147932c1880000 kernel config: https://syzkaller.appspot.com/x/.config?x=606e57fd25c5c6cc dashboard link: https://syzkaller.appspot.com/bug?extid=2f84b49020438f7a1e54 compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2 userspace arch: arm64 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13834435880000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1668d811880000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/82aa7741098d/disk-1621b6ea.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/f6be08c4e4c2/vmlinux-1621b6ea.xz kernel image: https://storage.googleapis.com/syzbot-assets/296b6946258a/Image-1621b6ea.gz.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/6366d3f12df1/mount_2.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+2f84b49020438f7a1e54@xxxxxxxxxxxxxxxxxxxxxxxxx Unable to handle kernel paging request at virtual address 000000d219eb1dcf Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=000000010ebbd000 [000000d219eb1dcf] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 3197 Comm: syz-executor428 Not tainted 6.1.0-rc4-syzkaller-31872-g1621b6eaebf7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : bdi_lookup_rb_node mm/backing-dev.c:824 [inline] pc : bdi_register_va+0x1d4/0x328 mm/backing-dev.c:883 lr : bdi_lookup_rb_node mm/backing-dev.c:820 [inline] lr : bdi_register_va+0x228/0x328 mm/backing-dev.c:883 sp : ffff80001335ba90 x29: ffff80001335bac0 x28: ffff0000ce994ec0 x27: 0000000000000000 x26: 0000000000008000 x25: 0000000000000000 x24: 0000000000000000 x23: ffff0000cea2f018 x22: 000000d219eb1dd7 x21: 000000d219eb1dd7 x20: 0000000000000040 x19: ffff0000cea29000 x18: 0000000000000322 x17: 4e51455300696462 x16: ffff80000db1a158 x15: ffff0000ce994ec0 x14: 0000000000000050 x13: 00000000ffffffff x12: ffff0000ce994ec0 x11: ff808000084395bc x10: 0000000000000000 x9 : ffff8000084395bc x8 : ffff0000ce994ec0 x7 : ffff8000084394f8 x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000 x2 : 0000000000000001 x1 : 0000000000000040 x0 : 0000000100000010 Call trace: bdi_register_va+0x1d4/0x328 mm/backing-dev.c:883 super_setup_bdi_name+0x84/0x120 fs/super.c:1590 super_setup_bdi+0x50/0x8c fs/super.c:1612 v9fs_fill_super fs/9p/vfs_super.c:76 [inline] v9fs_mount+0x1a4/0x568 fs/9p/vfs_super.c:137 legacy_get_tree+0x30/0x74 fs/fs_context.c:610 vfs_get_tree+0x40/0x140 fs/super.c:1531 do_new_mount+0x1dc/0x4e4 fs/namespace.c:3040 path_mount+0x358/0x890 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __arm64_sys_mount+0x2c4/0x3c4 fs/namespace.c:3568 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584 Code: f9416116 b4000396 90035097 910b02f7 (f85f82d5) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: f9416116 ldr x22, [x8, #704] 4: b4000396 cbz x22, 0x74 8: 90035097 adrp x23, 0x6a10000 c: 910b02f7 add x23, x23, #0x2c0 * 10: f85f82d5 ldur x21, [x22, #-8] <-- trapping instruction --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
