Hello, syzkaller hit the following crash on 2db767d9889cef087149a5eaa35c1497671fa40f git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master compiler: gcc (GCC) 7.1.1 20170620 .config is attached Raw console output is attached. Unfortunately, I don't have any reproducer for this bug yet. BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=0 stuck for 48s! BUG: workqueue lockup - pool cpus=0-1 flags=0x4 nice=0 stuck for 47s! Showing busy workqueues and worker pools: workqueue events: flags=0x0 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=4/256 pending: perf_sched_delayed, vmstat_shepherd, jump_label_update_timeout, cache_reap workqueue events_power_efficient: flags=0x80 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=4/256 pending: neigh_periodic_work, neigh_periodic_work, do_cache_clean, reg_check_chans_work workqueue mm_percpu_wq: flags=0x8 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 pending: vmstat_update workqueue writeback: flags=0x4e pwq 4: cpus=0-1 flags=0x4 nice=0 active=1/256 in-flight: 3401:wb_workfn workqueue kblockd: flags=0x18 pwq 1: cpus=0 node=0 flags=0x0 nice=-20 active=1/256 pending: blk_mq_timeout_work pool 4: cpus=0-1 flags=0x4 nice=0 hung=0s workers=11 idle: 3423 4249 92 21 3549 34 4803 5 4243 3414 audit: type=1326 audit(1512291140.021:615): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=7002 comm="syz-executor7" exe="/root/syz-executor7" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291140.044:616): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=7002 comm="syz-executor7" exe="/root/syz-executor7" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291140.045:617): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=7002 comm="syz-executor7" exe="/root/syz-executor7" sig=0 arch=c000003e syscall=55 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291140.045:618): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=7002 comm="syz-executor7" exe="/root/syz-executor7" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291140.045:619): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=7002 comm="syz-executor7" exe="/root/syz-executor7" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291140.047:620): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=7002 comm="syz-executor7" exe="/root/syz-executor7" sig=0 arch=c000003e syscall=257 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291140.047:621): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=7002 comm="syz-executor7" exe="/root/syz-executor7" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291140.047:622): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=7002 comm="syz-executor7" exe="/root/syz-executor7" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291140.048:623): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=7002 comm="syz-executor7" exe="/root/syz-executor7" sig=0 arch=c000003e syscall=16 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291140.049:624): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=7002 comm="syz-executor7" exe="/root/syz-executor7" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 netlink: 2 bytes leftover after parsing attributes in process `syz-executor2'. netlink: 2 bytes leftover after parsing attributes in process `syz-executor2'. netlink: 17 bytes leftover after parsing attributes in process `syz-executor7'. device gre0 entered promiscuous mode device gre0 entered promiscuous mode could not allocate digest TFM handle [vmnet1% could not allocate digest TFM handle [vmnet1% SELinux: unrecognized netlink message: protocol=0 nlmsg_type=7 sclass=netlink_route_socket pig=7627 comm=syz-executor3 sock: sock_set_timeout: `syz-executor6' (pid 7625) tries to set negative timeout Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7648 comm=syz-executor3 sock: sock_set_timeout: `syz-executor6' (pid 7625) tries to set negative timeout Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable SELinux: unrecognized netlink message: protocol=0 nlmsg_type=7 sclass=netlink_route_socket pig=7648 comm=syz-executor3 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7627 comm=syz-executor3 Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable netlink: 4 bytes leftover after parsing attributes in process `syz-executor3'. netlink: 4 bytes leftover after parsing attributes in process `syz-executor3'. netlink: 1 bytes leftover after parsing attributes in process `syz-executor3'. QAT: Invalid ioctl netlink: 1 bytes leftover after parsing attributes in process `syz-executor3'. QAT: Invalid ioctl FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 1 CPU: 1 PID: 7838 Comm: syz-executor4 Not tainted 4.15.0-rc1+ #205 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 fail_dump lib/fault-inject.c:51 [inline] should_fail+0x8c0/0xa40 lib/fault-inject.c:149 should_failslab+0xec/0x120 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3371 [inline] __do_kmalloc mm/slab.c:3709 [inline] __kmalloc_track_caller+0x5f/0x760 mm/slab.c:3726 memdup_user+0x2c/0x90 mm/util.c:164 msr_io+0xec/0x3b0 arch/x86/kvm/x86.c:2650 kvm_arch_vcpu_ioctl+0x31d/0x4710 arch/x86/kvm/x86.c:3566 kvm_vcpu_ioctl+0x240/0x1010 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2726 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:686 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x4529d9 RSP: 002b:00007fd7722d4c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd7722d4aa0 RCX: 00000000004529d9 RDX: 0000000020002000 RSI: 000000004008ae89 RDI: 0000000000000016 RBP: 00007fd7722d4a90 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000004b759b R13: 00007fd7722d4bc8 R14: 00000000004b759b R15: 0000000000000000 device lo left promiscuous mode device lo entered promiscuous mode device lo left promiscuous mode kvm_hv_set_msr: 127 callbacks suppressed kvm [8010]: vcpu0, guest rIP: 0x9112 Hyper-V uhandled wrmsr: 0x4000008e data 0x47 kvm [8010]: vcpu0, guest rIP: 0x9112 Hyper-V uhandled wrmsr: 0x4000008c data 0x47 kvm [8010]: vcpu0, guest rIP: 0x9112 Hyper-V uhandled wrmsr: 0x4000008a data 0x47 kvm [8010]: vcpu0, guest rIP: 0x9112 Hyper-V uhandled wrmsr: 0x40000088 data 0x47 kvm [8010]: vcpu0, guest rIP: 0x9112 Hyper-V uhandled wrmsr: 0x40000086 data 0x47 program syz-executor2 is using a deprecated SCSI ioctl, please convert it to SG_IO sd 0:0:1:0: ioctl_internal_command: ILLEGAL REQUEST asc=0x20 ascq=0x0 program syz-executor2 is using a deprecated SCSI ioctl, please convert it to SG_IO sd 0:0:1:0: ioctl_internal_command: ILLEGAL REQUEST asc=0x20 ascq=0x0 netlink: 2 bytes leftover after parsing attributes in process `syz-executor5'. program syz-executor2 is using a deprecated SCSI ioctl, please convert it to SG_IO sd 0:0:1:0: ioctl_internal_command: ILLEGAL REQUEST asc=0x20 ascq=0x0 netlink: 2 bytes leftover after parsing attributes in process `syz-executor5'. program syz-executor2 is using a deprecated SCSI ioctl, please convert it to SG_IO sd 0:0:1:0: ioctl_internal_command: ILLEGAL REQUEST asc=0x20 ascq=0x0 kauditd_printk_skb: 264 callbacks suppressed audit: type=1326 audit(1512291148.643:889): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=8160 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291148.643:890): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=8160 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291148.643:891): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=8160 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=22 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291148.650:892): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=8160 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291148.650:893): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=8160 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=54 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291148.650:894): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=8160 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291148.650:895): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=8160 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=298 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291148.672:896): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=8160 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 audit: type=1326 audit(1512291148.705:897): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=8160 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=2 compat=0 ip=0x40cd11 code=0x7ffc0000 audit: type=1326 audit(1512291148.705:898): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=8160 comm="syz-executor5" exe="/root/syz-executor5" sig=0 arch=c000003e syscall=202 compat=0 ip=0x4529d9 code=0x7ffc0000 QAT: Invalid ioctl QAT: Invalid ioctl --- This bug is generated by a dumb bot. 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