Hello, syzbot found the following issue on: HEAD commit: 87066fdd2e30 Revert "mm/secretmem: use refcount_t instead .. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1305869f300000 kernel config: https://syzkaller.appspot.com/x/.config?x=59f3ef2b4077575 dashboard link: https://syzkaller.appspot.com/bug?extid=e551332be0091d437c65 compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+e551332be0091d437c65@xxxxxxxxxxxxxxxxxxxxxxxxx vcan0: j1939_tp_txtimer: 0xffff888020eb8400: tx retry count reached ------------[ cut here ]------------ WARNING: CPU: 1 PID: 10368 at net/can/j1939/transport.c:1090 j1939_session_deactivate net/can/j1939/transport.c:1090 [inline] WARNING: CPU: 1 PID: 10368 at net/can/j1939/transport.c:1090 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1100 [inline] WARNING: CPU: 1 PID: 10368 at net/can/j1939/transport.c:1090 j1939_tp_txtimer+0x25a9/0x2a80 net/can/j1939/transport.c:1169 Modules linked in: CPU: 1 PID: 10368 Comm: syz-executor.3 Not tainted 5.15.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:j1939_session_deactivate net/can/j1939/transport.c:1090 [inline] RIP: 0010:j1939_session_deactivate_activate_next net/can/j1939/transport.c:1100 [inline] RIP: 0010:j1939_tp_txtimer+0x25a9/0x2a80 net/can/j1939/transport.c:1169 Code: 83 00 fb e9 07 ef ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 00 f0 ff ff 48 89 df e8 d1 6d bd f8 e9 f3 ef ff ff e8 a7 fe 71 f8 <0f> 0b e9 3d fa ff ff e8 9b fe 71 f8 e9 fe 01 00 00 89 d9 80 e1 07 RSP: 0018:ffffc90000dc0aa0 EFLAGS: 00010246 RAX: ffffffff8911b719 RBX: 0000000000000001 RCX: ffff88808b478000 RDX: 0000000000000302 RSI: 0000000000000001 RDI: 0000000000000002 RBP: ffffc90000dc0c50 R08: ffffffff8911b14f R09: ffffed10041d7086 R10: ffffed10041d7086 R11: 0000000000000000 R12: ffff888020eb8400 R13: 1ffff920001b8174 R14: ffff88807ae71070 R15: dffffc0000000000 FS: 00007f32687a1700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f91a465f000 CR3: 00000000868be000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 000000000000d0eb DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: <IRQ> __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x50b/0xa60 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x1b7/0x5d0 kernel/time/hrtimer.c:1766 __do_softirq+0x392/0x7a3 kernel/softirq.c:558 __irq_exit_rcu+0xec/0x170 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1097 </IRQ> asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:finish_lock_switch+0x1c5/0x350 kernel/sched/core.c:4695 Code: be ff ff ff ff e8 db ca 9e 08 85 c0 74 37 4d 85 e4 75 58 0f 1f 44 00 00 4c 89 ff e8 a5 73 a1 08 e8 30 74 2e 00 fb 48 83 c4 10 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 0f 0b 4d 85 e4 0f 85 4a ff ff ff RSP: 0018:ffffc9000565df28 EFLAGS: 00000286 RAX: f560f1fddc198c00 RBX: 1ffff110173a6400 RCX: ffffffff8165c2f1 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff8880b9d32000 R08: dffffc0000000000 R09: fffffbfff1fa37ec R10: fffffbfff1fa37ec R11: 0000000000000000 R12: 0000000000000000 R13: ffff8880b9d32298 R14: dffffc0000000000 R15: ffff8880b9d31540 finish_task_switch+0x140/0x630 kernel/sched/core.c:4812 context_switch kernel/sched/core.c:4943 [inline] __schedule+0xb7a/0x1460 kernel/sched/core.c:6287 preempt_schedule_common kernel/sched/core.c:6459 [inline] preempt_schedule+0x14d/0x190 kernel/sched/core.c:6484 preempt_schedule_thunk+0x16/0x18 unwind_next_frame+0x13fc/0x1fa0 arch/x86/kernel/unwind_orc.c:611 arch_stack_walk+0x112/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x11b/0x1e0 kernel/stacktrace.c:121 save_stack+0xff/0x200 mm/page_owner.c:119 __set_page_owner+0x42/0x2f0 mm/page_owner.c:181 prep_new_page mm/page_alloc.c:2424 [inline] get_page_from_freelist+0x779/0xa30 mm/page_alloc.c:4153 __alloc_pages+0x255/0x580 mm/page_alloc.c:5375 __page_cache_alloc+0x79/0x1c0 mm/filemap.c:1022 page_cache_ra_unbounded+0x2ee/0x9b0 mm/readahead.c:216 page_cache_async_readahead include/linux/pagemap.h:906 [inline] filemap_readahead mm/filemap.c:2520 [inline] filemap_get_pages+0x6b9/0xd90 mm/filemap.c:2561 filemap_read+0x3be/0x1060 mm/filemap.c:2628 __kernel_read+0x5d0/0xaf0 fs/read_write.c:443 integrity_kernel_read+0xac/0xf0 security/integrity/iint.c:199 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:484 [inline] ima_calc_file_shash security/integrity/ima/ima_crypto.c:515 [inline] ima_calc_file_hash+0x1584/0x1b90 security/integrity/ima/ima_crypto.c:572 ima_collect_measurement+0x27d/0x510 security/integrity/ima/ima_api.c:254 process_measurement+0x101d/0x1dd0 security/integrity/ima/ima_main.c:337 ima_file_check+0xed/0x170 security/integrity/ima/ima_main.c:516 do_open fs/namei.c:3430 [inline] path_openat+0x2917/0x3670 fs/namei.c:3561 do_filp_open+0x277/0x4f0 fs/namei.c:3588 do_sys_openat2+0x13b/0x500 fs/open.c:1200 do_sys_open fs/open.c:1216 [inline] __do_sys_open fs/open.c:1224 [inline] __se_sys_open fs/open.c:1220 [inline] __x64_sys_open+0x221/0x270 fs/open.c:1220 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f326b22ba39 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f32687a1188 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f326b32ef60 RCX: 00007f326b22ba39 RDX: 0000000000000000 RSI: 000000000014113e RDI: 0000000020000200 RBP: 00007f326b285e8f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffecc05baef R14: 00007f32687a1300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: be ff ff ff ff mov $0xffffffff,%esi 5: e8 db ca 9e 08 callq 0x89ecae5 a: 85 c0 test %eax,%eax c: 74 37 je 0x45 e: 4d 85 e4 test %r12,%r12 11: 75 58 jne 0x6b 13: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 18: 4c 89 ff mov %r15,%rdi 1b: e8 a5 73 a1 08 callq 0x8a173c5 20: e8 30 74 2e 00 callq 0x2e7455 25: fb sti 26: 48 83 c4 10 add $0x10,%rsp * 2a: 5b pop %rbx <-- trapping instruction 2b: 41 5c pop %r12 2d: 41 5d pop %r13 2f: 41 5e pop %r14 31: 41 5f pop %r15 33: 5d pop %rbp 34: c3 retq 35: 0f 0b ud2 37: 4d 85 e4 test %r12,%r12 3a: 0f 85 4a ff ff ff jne 0xffffff8a --- This report is generated by a bot. 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