bisecting fixing commit since f4bc5bbb5fef3cf421ba3485d6d383c27ec473ed building syzkaller on 0b33604d8e2793b82ec89abecf82d92b82e3d410 testing commit f4bc5bbb5fef3cf421ba3485d6d383c27ec473ed compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: c66633c75c3ac69574dcf4abf44a134141fab5e73159d76ae99db0844c175b71 run #0: crashed: general protection fault in l2cap_chan_timeout run #1: crashed: general protection fault in l2cap_chan_timeout run #2: crashed: general protection fault in l2cap_chan_timeout run #3: crashed: general protection fault in l2cap_chan_timeout run #4: crashed: general protection fault in l2cap_chan_timeout run #5: crashed: general protection fault in l2cap_chan_timeout run #6: crashed: general protection fault in l2cap_chan_timeout run #7: OK run #8: crashed: general protection fault in l2cap_chan_timeout run #9: crashed: general protection fault in l2cap_chan_timeout run #10: crashed: general protection fault in l2cap_chan_timeout run #11: crashed: general protection fault in l2cap_chan_timeout run #12: crashed: general protection fault in l2cap_chan_timeout run #13: crashed: general protection fault in l2cap_chan_timeout run #14: crashed: general protection fault in l2cap_chan_timeout run #15: crashed: general protection fault in l2cap_chan_timeout run #16: OK run #17: crashed: general protection fault in l2cap_chan_timeout run #18: OK run #19: OK testing current HEAD 874c8ca1e60b2c564a48f7e7acc40d328d5c8733 testing commit 874c8ca1e60b2c564a48f7e7acc40d328d5c8733 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 9c6e8e81b711c7ffda9480838d072b119cca12a7e4116601abb3e297a689ddd0 run #0: crashed: INFO: rcu detected stall in corrupted run #1: crashed: INFO: rcu detected stall in corrupted run #2: crashed: INFO: rcu detected stall in corrupted run #3: boot failed: INFO: task hung in add_early_randomness run #4: boot failed: INFO: task hung in add_early_randomness run #5: boot failed: INFO: task hung in add_early_randomness run #6: boot failed: INFO: task hung in add_early_randomness run #7: boot failed: INFO: task hung in add_early_randomness run #8: OK run #9: crashed: general protection fault in l2cap_chan_timeout revisions tested: 2, total time: 39m0.429877679s (build: 13m38.768617779s, test: 24m42.851247509s) the crash still happens on HEAD commit msg: netfs: Fix gcc-12 warning by embedding vfs inode in netfs_i_context crash: general protection fault in l2cap_chan_timeout general protection fault, probably for non-canonical address 0xdffffc000000005a: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000002d0-0x00000000000002d7] CPU: 1 PID: 3623 Comm: kworker/1:3 Not tainted 5.19.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events l2cap_chan_timeout RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:582 [inline] RIP: 0010:__mutex_lock+0xec/0x1350 kernel/locking/mutex.c:747 Code: d0 7c 08 84 d2 0f 85 4f 0f 00 00 8b 15 dd 94 aa 06 85 d2 75 29 48 8d 7d 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 37 0f 00 00 48 3b 6d 60 0f 85 ce 08 00 00 bf 01 RSP: 0018:ffffc90002d5fb98 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 000000000000005a RSI: ffffffff88eba7e0 RDI: 00000000000002d0 RBP: 0000000000000270 R08: ffffffff8792e51c R09: ffffffff8ca4d857 R10: fffffbfff1949b0a R11: 0000000000000001 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff888145799020 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000140 CR3: 0000000068b07000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: l2cap_chan_timeout+0x5c/0x280 net/bluetooth/l2cap_core.c:422 process_one_work+0x841/0x13a0 kernel/workqueue.c:2289 worker_thread+0x598/0xec0 kernel/workqueue.c:2436 kthread+0x299/0x340 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:582 [inline] RIP: 0010:__mutex_lock+0xec/0x1350 kernel/locking/mutex.c:747 Code: d0 7c 08 84 d2 0f 85 4f 0f 00 00 8b 15 dd 94 aa 06 85 d2 75 29 48 8d 7d 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 37 0f 00 00 48 3b 6d 60 0f 85 ce 08 00 00 bf 01 RSP: 0018:ffffc90002d5fb98 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 000000000000005a RSI: ffffffff88eba7e0 RDI: 00000000000002d0 RBP: 0000000000000270 R08: ffffffff8792e51c R09: ffffffff8ca4d857 R10: fffffbfff1949b0a R11: 0000000000000001 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff888145799020 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2458800668 CR3: 000000000aa8e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: d0 7c 08 84 sarb -0x7c(%rax,%rcx,1) 4: d2 0f rorb %cl,(%rdi) 6: 85 4f 0f test %ecx,0xf(%rdi) 9: 00 00 add %al,(%rax) b: 8b 15 dd 94 aa 06 mov 0x6aa94dd(%rip),%edx # 0x6aa94ee 11: 85 d2 test %edx,%edx 13: 75 29 jne 0x3e 15: 48 8d 7d 60 lea 0x60(%rbp),%rdi 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 20: fc ff df 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 37 0f 00 00 jne 0xf6b 34: 48 3b 6d 60 cmp 0x60(%rbp),%rbp 38: 0f 85 ce 08 00 00 jne 0x90c 3e: bf .byte 0xbf 3f: 01 .byte 0x1