On 11/4/24 12:11, Vlastimil Babka wrote: > On 11/3/24 11:46, syzbot wrote: >> Hello, >> >> syzbot found the following issue on: >> >> HEAD commit: f9f24ca362a4 Add linux-next specific files for 20241031 >> git tree: linux-next >> console output: https://syzkaller.appspot.com/x/log.txt?x=1648155f980000 >> kernel config: https://syzkaller.appspot.com/x/.config?x=328572ed4d152be9 >> dashboard link: https://syzkaller.appspot.com/bug?extid=39f85d612b7c20d8db48 >> compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 >> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16806e87980000 >> >> Downloadable assets: >> disk image: https://storage.googleapis.com/syzbot-assets/eb84549dd6b3/disk-f9f24ca3.raw.xz >> vmlinux: https://storage.googleapis.com/syzbot-assets/beb29bdfa297/vmlinux-f9f24ca3.xz >> kernel image: https://storage.googleapis.com/syzbot-assets/8881fe3245ad/bzImage-f9f24ca3.xz >> >> IMPORTANT: if you fix the issue, please add the following tag to the commit: >> Reported-by: syzbot+39f85d612b7c20d8db48@xxxxxxxxxxxxxxxxxxxxxxxxx >> >> ============================= >> [ BUG: Invalid wait context ] >> 6.12.0-rc5-next-20241031-syzkaller #0 Not tainted >> ----------------------------- >> syz.0.49/6178 is trying to lock: >> ffff88813fffc298 (&zone->lock){-.-.}-{3:3}, at: rmqueue_bulk mm/page_alloc.c:2328 [inline] >> ffff88813fffc298 (&zone->lock){-.-.}-{3:3}, at: __rmqueue_pcplist+0x4c6/0x2b70 mm/page_alloc.c:3022 >> other info that might help us debug this: >> context-{2:2} > > Seems like another fallout of > 560af5dc839e ("lockdep: Enable PROVE_RAW_LOCK_NESTING with PROVE_LOCKING") > >> 4 locks held by syz.0.49/6178: >> #0: ffff888031745be0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:189 [inline] >> #0: ffff888031745be0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x165/0xcb0 mm/mmap.c:1677 >> #1: ffffffff8e939f20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] >> #1: ffffffff8e939f20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] >> #1: ffffffff8e939f20 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x82/0x380 mm/pgtable-generic.c:287 >> #2: ffff88803007c978 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] >> #2: ffff88803007c978 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: __pte_offset_map_lock+0x1ba/0x300 mm/pgtable-generic.c:402 >> #3: ffff8880b8744618 (&pcp->lock){+.+.}-{3:3}, at: spin_trylock include/linux/spinlock.h:361 [inline] >> #3: ffff8880b8744618 (&pcp->lock){+.+.}-{3:3}, at: rmqueue_pcplist mm/page_alloc.c:3051 [inline] >> #3: ffff8880b8744618 (&pcp->lock){+.+.}-{3:3}, at: rmqueue mm/page_alloc.c:3095 [inline] >> #3: ffff8880b8744618 (&pcp->lock){+.+.}-{3:3}, at: get_page_from_freelist+0x7e2/0x3870 mm/page_alloc.c:3492 >> stack backtrace: >> CPU: 1 UID: 0 PID: 6178 Comm: syz.0.49 Not tainted 6.12.0-rc5-next-20241031-syzkaller #0 >> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 >> Call Trace: >> <IRQ> >> __dump_stack lib/dump_stack.c:94 [inline] >> dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 >> print_lock_invalid_wait_context kernel/locking/lockdep.c:4826 [inline] >> check_wait_context kernel/locking/lockdep.c:4898 [inline] >> __lock_acquire+0x15a8/0x2100 kernel/locking/lockdep.c:5176 >> lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 >> __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] >> _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 >> rmqueue_bulk mm/page_alloc.c:2328 [inline] >> __rmqueue_pcplist+0x4c6/0x2b70 mm/page_alloc.c:3022 >> rmqueue_pcplist mm/page_alloc.c:3064 [inline] >> rmqueue mm/page_alloc.c:3095 [inline] >> get_page_from_freelist+0x895/0x3870 mm/page_alloc.c:3492 >> __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4771 >> alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 >> stack_depot_save_flags+0x666/0x830 lib/stackdepot.c:627 >> save_stack+0x109/0x1f0 mm/page_owner.c:157 >> __set_page_owner+0x92/0x800 mm/page_owner.c:320 >> set_page_owner include/linux/page_owner.h:32 [inline] >> post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1541 >> prep_new_page mm/page_alloc.c:1549 [inline] >> get_page_from_freelist+0x3725/0x3870 mm/page_alloc.c:3495 >> __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4771 >> alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 >> stack_depot_save_flags+0x666/0x830 lib/stackdepot.c:627 >> kasan_save_stack+0x4f/0x60 mm/kasan/common.c:48 >> __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:544 >> task_work_add+0xd9/0x490 kernel/task_work.c:77 > > It seems the decision if stack depot is allowed to allocate here depends on > TWAF_NO_ALLOC added only recently. So does it mean it doesn't work as intended? I guess __run_posix_cpu_timers() needs to pass TWAF_NO_ALLOC too? > >> __run_posix_cpu_timers kernel/time/posix-cpu-timers.c:1219 [inline] >> run_posix_cpu_timers+0x6ac/0x810 kernel/time/posix-cpu-timers.c:1418 >> tick_sched_handle kernel/time/tick-sched.c:276 [inline] >> tick_nohz_handler+0x37c/0x500 kernel/time/tick-sched.c:297 >> __run_hrtimer kernel/time/hrtimer.c:1691 [inline] >> __hrtimer_run_queues+0x551/0xd50 kernel/time/hrtimer.c:1755 >> hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817 >> local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] >> __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 >> instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] >> sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1049 >> asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 >> RIP: 0010:variable_ffs arch/x86/include/asm/bitops.h:321 [inline] >> RIP: 0010:handle_softirqs+0x1e3/0x980 kernel/softirq.c:542 >> Code: 7c 24 70 45 0f b7 e4 48 c7 c7 20 c5 09 8c e8 c4 6c 6c 0a 65 66 c7 05 32 53 ac 7e 00 00 e8 05 67 45 00 fb 49 c7 c6 c0 a0 60 8e <b8> ff ff ff ff 41 0f bc c4 41 89 c7 41 ff c7 0f 84 eb 03 00 00 44 >> RSP: 0018:ffffc90000a18e40 EFLAGS: 00000286 >> RAX: 959a1636e72c7c00 RBX: ffffc90000a18ee0 RCX: ffffffff8170c69a >> RDX: dffffc0000000000 RSI: ffffffff8c0ad3a0 RDI: ffffffff8c604dc0 >> RBP: ffffc90000a18f50 R08: ffffffff942cd847 R09: 1ffffffff2859b08 >> R10: dffffc0000000000 R11: fffffbfff2859b09 R12: 0000000000000010 >> R13: 0000000000000000 R14: ffffffff8e60a0c0 R15: 1ffff11003cec000 >> __do_softirq kernel/softirq.c:588 [inline] >> invoke_softirq kernel/softirq.c:428 [inline] >> __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 >> irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 >> common_interrupt+0xb9/0xd0 arch/x86/kernel/irq.c:278 >> </IRQ> >> <TASK> >> asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 >> RIP: 0010:zap_pmd_range mm/memory.c:1753 [inline] >> RIP: 0010:zap_pud_range mm/memory.c:1782 [inline] >> RIP: 0010:zap_p4d_range mm/memory.c:1803 [inline] >> RIP: 0010:unmap_page_range+0x1ffd/0x4230 mm/memory.c:1824 >> Code: 02 00 00 4c 8d bc 24 c0 02 00 00 48 8b 44 24 48 48 98 48 89 c1 48 c1 e1 0c 49 01 cd 4c 3b ac 24 98 00 00 00 0f 84 44 14 00 00 <4c> 89 6c 24 28 48 8b 5c 24 38 48 8d 1c c3 e8 50 01 b2 ff e9 ec e9 >> RSP: 0018:ffffc9000303f560 EFLAGS: 00000287 >> RAX: 0000000000000001 RBX: ffff88803023b5c8 RCX: 0000000000001000 >> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 >> RBP: ffffc9000303f890 R08: ffffffff81e30b9c R09: 1ffffd4000333df6 >> R10: dffffc0000000000 R11: fffff94000333df7 R12: dffffc0000000000 >> R13: 00000000200ba000 R14: ffffc9000303f7e0 R15: ffffc9000303f820 >> unmap_vmas+0x3cc/0x5f0 mm/memory.c:1914 >> exit_mmap+0x292/0xcb0 mm/mmap.c:1693 >> __mmput+0x115/0x390 kernel/fork.c:1344 >> exit_mm+0x220/0x310 kernel/exit.c:570 >> do_exit+0x9b2/0x28e0 kernel/exit.c:925 >> do_group_exit+0x207/0x2c0 kernel/exit.c:1087 >> __do_sys_exit_group kernel/exit.c:1098 [inline] >> __se_sys_exit_group kernel/exit.c:1096 [inline] >> __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096 >> x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232 >> do_syscall_x64 arch/x86/entry/common.c:52 [inline] >> do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 >> entry_SYSCALL_64_after_hwframe+0x77/0x7f >> RIP: 0033:0x7faae5f7e719 >> Code: Unable to access opcode bytes at 0x7faae5f7e6ef. >> RSP: 002b:00007ffc97dbc998 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 >> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007faae5f7e719 >> RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 >> RBP: 00007ffc97dbc9ec R08: 00007ffc97dbca7f R09: 0000000000013547 >> R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000032 >> R13: 0000000000013547 R14: 0000000000013547 R15: 00007ffc97dbca40 >> </TASK> >> ---------------- >> Code disassembly (best guess): >> 0: 7c 24 jl 0x26 >> 2: 70 45 jo 0x49 >> 4: 0f b7 e4 movzwl %sp,%esp >> 7: 48 c7 c7 20 c5 09 8c mov $0xffffffff8c09c520,%rdi >> e: e8 c4 6c 6c 0a call 0xa6c6cd7 >> 13: 65 66 c7 05 32 53 ac movw $0x0,%gs:0x7eac5332(%rip) # 0x7eac534f >> 1a: 7e 00 00 >> 1d: e8 05 67 45 00 call 0x456727 >> 22: fb sti >> 23: 49 c7 c6 c0 a0 60 8e mov $0xffffffff8e60a0c0,%r14 >> * 2a: b8 ff ff ff ff mov $0xffffffff,%eax <-- trapping instruction >> 2f: 41 0f bc c4 bsf %r12d,%eax >> 33: 41 89 c7 mov %eax,%r15d >> 36: 41 ff c7 inc %r15d >> 39: 0f 84 eb 03 00 00 je 0x42a >> 3f: 44 rex.R >> >> >> --- >> 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. >> >> If the report is already addressed, let syzbot know by replying with: >> #syz fix: exact-commit-title >> >> If you want syzbot to run the reproducer, reply with: >> #syz test: git://repo/address.git branch-or-commit-hash >> If you attach or paste a git patch, syzbot will apply it before testing. >> >> If you want to overwrite report's subsystems, reply with: >> #syz set subsystems: new-subsystem >> (See the list of subsystem names on the web dashboard) >> >> If the report is a duplicate of another one, reply with: >> #syz dup: exact-subject-of-another-report >> >> If you want to undo deduplication, reply with: >> #syz undup >
