general protection fault, probably for non-canonical address 0xdffffc000000001f: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x00000000000000f8-0x00000000000000ff] CPU: 1 PID: 5150 Comm: kworker/1:6 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: pm pm_runtime_work RIP: 0010:serial8250_tx_chars+0x28c/0x8a0 drivers/tty/serial/8250/8250_port.c:1809 Code: 1a 39 c7 fc 48 8b 2b 48 8b 44 24 20 42 0f b6 04 38 84 c0 0f 85 97 02 00 00 48 8b 04 24 48 63 00 48 01 c5 48 89 e8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 99 02 00 00 0f b6 6d 00 48 8b 44 24 58 RSP: 0018:ffffc900041e7830 EFLAGS: 00010012 RAX: 000000000000001f RBX: ffff88801f3f0fd0 RCX: 1ffffffff290120f RDX: 1ffffffff2901259 RSI: 00000000000000fb RDI: ffffffff948092d0 RBP: 00000000000000fb R08: ffffffff85310a97 R09: fffff5200083cf00 R10: dffffc0000000000 R11: ffffffff8531c3e0 R12: ffffffff94809070 R13: ffffffff94809128 R14: ffffffff94809020 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9840979198 CR3: 0000000060422000 CR4: 0000000000350ef0 Call Trace: __start_tx+0x32e/0x470 drivers/tty/serial/8250/8250_port.c:1544 serial_port_runtime_suspend+0x21f/0x2e0 drivers/tty/serial/serial_port.c:62 __rpm_callback+0x2e1/0x790 drivers/base/power/runtime.c:394 rpm_callback drivers/base/power/runtime.c:448 [inline] rpm_suspend+0x867/0x1780 drivers/base/power/runtime.c:672 pm_runtime_work+0x175/0x210 drivers/base/power/runtime.c:976 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa02/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f2/0x390 kernel/kthread.c:388 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:serial8250_tx_chars+0x28c/0x8a0 drivers/tty/serial/8250/8250_port.c:1809 Code: 1a 39 c7 fc 48 8b 2b 48 8b 44 24 20 42 0f b6 04 38 84 c0 0f 85 97 02 00 00 48 8b 04 24 48 63 00 48 01 c5 48 89 e8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 99 02 00 00 0f b6 6d 00 48 8b 44 24 58 RSP: 0018:ffffc900041e7830 EFLAGS: 00010012 RAX: 000000000000001f RBX: ffff88801f3f0fd0 RCX: 1ffffffff290120f RDX: 1ffffffff2901259 RSI: 00000000000000fb RDI: ffffffff948092d0 RBP: 00000000000000fb R08: ffffffff85310a97 R09: fffff5200083cf00 R10: dffffc0000000000 R11: ffffffff8531c3e0 R12: ffffffff94809070 R13: ffffffff94809128 R14: ffffffff94809020 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9840979198 CR3: 0000000060422000 CR4: 0000000000350ef0 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 39 c7 cmp %eax,%edi 2: fc cld 3: 48 8b 2b mov (%rbx),%rbp 6: 48 8b 44 24 20 mov 0x20(%rsp),%rax b: 42 0f b6 04 38 movzbl (%rax,%r15,1),%eax 10: 84 c0 test %al,%al 12: 0f 85 97 02 00 00 jne 0x2af 18: 48 8b 04 24 mov (%rsp),%rax 1c: 48 63 00 movslq (%rax),%rax 1f: 48 01 c5 add %rax,%rbp 22: 48 89 e8 mov %rbp,%rax 25: 48 c1 e8 03 shr $0x3,%rax * 29: 42 0f b6 04 38 movzbl (%rax,%r15,1),%eax <-- trapping instruction 2e: 84 c0 test %al,%al 30: 0f 85 99 02 00 00 jne 0x2cf 36: 0f b6 6d 00 movzbl 0x0(%rbp),%ebp 3a: 48 8b 44 24 58 mov 0x58(%rsp),%rax