Hello, syzbot found the following issue on: HEAD commit: bbed346d5a96 Merge branch 'for-next/core' 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=100804a6880000 kernel config: https://syzkaller.appspot.com/x/.config?x=3a4a45d2d827c1e dashboard link: https://syzkaller.appspot.com/bug?extid=77e4f005cb899d4268d1 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=111fa5f2880000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13687212880000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/e8e91bc79312/disk-bbed346d.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/c1cb3fb3b77e/vmlinux-bbed346d.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/c8d7f5e1917f/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+77e4f005cb899d4268d1@xxxxxxxxxxxxxxxxxxxxxxxxx NILFS (loop0): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds Unable to handle kernel NULL pointer dereference at virtual address 0000000000000168 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=0000000108bcf000 [0000000000000168] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 3032 Comm: segctord Not tainted 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : _compound_head include/linux/page-flags.h:253 [inline] pc : lock_page+0x28/0x1e0 include/linux/pagemap.h:958 lr : lock_page+0x28/0x1e0 include/linux/pagemap.h:956 sp : ffff80001290bc00 x29: ffff80001290bc00 x28: ffff80001290bde0 x27: 000000000000001b x26: fffffc000330d7c0 x25: ffff0000caa56d68 x24: ffff0000ca9fb1c0 x23: 0000000000000080 x22: ffff0000ca9fb130 x21: 0000000000000160 x20: ffff0000c91e10b8 x19: 0000000000000160 x18: 00000000000000c0 x17: ffff80000dd0b198 x16: ffff80000db49158 x15: ffff0000c3e63500 x14: 0000000000000000 x13: 00000000ffffffff x12: ffff0000c3e63500 x11: ff808000095d1a0c x10: 0000000000000000 x9 : 0000000000000000 x8 : 0000000000000000 x7 : ffff80000856806c x6 : 0000000000000000 x5 : 0000000000000080 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000000 x1 : ffff80000cb431b1 x0 : 0000000000000000 Call trace: lock_page+0x28/0x1e0 include/linux/pagemap.h:956 nilfs_segctor_prepare_write+0x6c/0x21c fs/nilfs2/segment.c:1658 nilfs_segctor_do_construct+0x9f4/0xee8 fs/nilfs2/segment.c:2068 nilfs_segctor_construct+0xa0/0x380 fs/nilfs2/segment.c:2375 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2483 [inline] nilfs_segctor_thread+0x180/0x660 fs/nilfs2/segment.c:2566 kthread+0x12c/0x158 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 Code: 9001df80 912a5000 52807781 97c7bd0e (f9400674) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 9001df80 adrp x0, 0x3bf0000 4: 912a5000 add x0, x0, #0xa94 8: 52807781 mov w1, #0x3bc // #956 c: 97c7bd0e bl 0xffffffffff1ef444 * 10: f9400674 ldr x20, [x19, #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
