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-rw-r--r--results/classifier/118/performance/1750229770
1 files changed, 0 insertions, 770 deletions
diff --git a/results/classifier/118/performance/1750229 b/results/classifier/118/performance/1750229
deleted file mode 100644
index d206f10f2..000000000
--- a/results/classifier/118/performance/1750229
+++ /dev/null
@@ -1,770 +0,0 @@
-performance: 0.913
-permissions: 0.912
-mistranslation: 0.901
-debug: 0.898
-semantic: 0.892
-graphic: 0.887
-register: 0.885
-architecture: 0.885
-assembly: 0.880
-device: 0.868
-network: 0.864
-arm: 0.861
-files: 0.859
-PID: 0.854
-kernel: 0.854
-virtual: 0.851
-user-level: 0.843
-boot: 0.836
-risc-v: 0.835
-hypervisor: 0.829
-TCG: 0.819
-KVM: 0.818
-peripherals: 0.810
-socket: 0.804
-ppc: 0.796
-x86: 0.776
-vnc: 0.774
-VMM: 0.731
-i386: 0.532
-
-virtio-blk-pci regression: softlock in guest kernel at module loading
-
-Hello,
-
-I am running qemu from master git branch on x86_64 host with kernel is 4.4.114. I've found that commit
-
-    9a4c0e220d8a "hw/virtio-pci: fix virtio behaviour"
-
-introduces an regression with the following command:
-
-    qemu-system-x86_64 -enable-kvm -nodefaults -no-reboot -nographic -vga none -runas qemu -kernel .build.kernel.kvm -initrd .build.initrd.kvm -append 'panic=1 softlockup_panic=1 no-kvmclock nmi_watchdog=0 console=ttyS0 root=/dev/disk/by-id/virtio-0' -m 2048 -drive file=./root,format=raw,if=none,id=disk,serial=0,cache=unsafe -device virtio-blk-pci,drive=disk -serial stdio -smp 2
-
-Starting from this commit to master the following happens with a wide variety of guest kernels (4.4 to 4.15):
-
-[   62.428107] BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=-20 stuck for 59s!
-[   62.437426] Showing busy workqueues and worker pools:
-[   62.443117] workqueue events: flags=0x0
-[   62.447512]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
-[   62.448161]     pending: check_corruption
-[   62.458570] workqueue kblockd: flags=0x18
-[   62.463082]   pwq 1: cpus=0 node=0 flags=0x0 nice=-20 active=3/256
-[   62.463082]     in-flight: 4:blk_mq_run_work_fn
-[   62.463082]     pending: blk_mq_run_work_fn, blk_mq_timeout_work
-[   62.474831] pool 1: cpus=0 node=0 flags=0x0 nice=-20 hung=59s workers=2 idle: 214
-[   62.492121] INFO: rcu_preempt detected stalls on CPUs/tasks:
-[   62.492121]  Tasks blocked on level-0 rcu_node (CPUs 0-1): P4
-[   62.492121]  (detected by 0, t=15002 jiffies, g=-130, c=-131, q=32)
-[   62.492121] kworker/0:0H    R  running task        0     4      2 0x80000000
-[   62.492121] Workqueue: kblockd blk_mq_run_work_fn
-[   62.492121] Call Trace:
-[   62.492121]  <IRQ>
-[   62.492121]  sched_show_task+0xdf/0x100
-[   62.492121]  rcu_print_detail_task_stall_rnp+0x48/0x69
-[   62.492121]  rcu_check_callbacks+0x93d/0x9d0
-[   62.492121]  ? tick_sched_do_timer+0x40/0x40
-[   62.492121]  update_process_times+0x28/0x50
-[   62.492121]  tick_sched_handle+0x22/0x70
-[   62.492121]  tick_sched_timer+0x34/0x70
-[   62.492121]  __hrtimer_run_queues+0xcc/0x250
-[   62.492121]  hrtimer_interrupt+0xab/0x1f0
-[   62.492121]  smp_apic_timer_interrupt+0x62/0x150
-[   62.492121]  apic_timer_interrupt+0xa2/0xb0
-[   62.492121]  </IRQ>
-[   62.492121] RIP: 0010:iowrite16+0x1d/0x30
-[   62.492121] RSP: 0018:ffffa477c034fcc8 EFLAGS: 00010292 ORIG_RAX: ffffffffffffff11
-[   62.492121] RAX: ffffffffa24fbdb0 RBX: ffff92a1f8f82000 RCX: 0000000000000001
-[   62.492121] RDX: ffffa477c0371000 RSI: ffffa477c0371000 RDI: 0000000000000000
-[   62.492121] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000001080020
-[   62.492121] R10: ffffdc7cc1e4fc00 R11: 0000000000000000 R12: 0000000000000000
-[   62.492121] R13: 0000000000000000 R14: ffff92a1f93f0000 R15: ffff92a1f8e1aa80
-[   62.492121]  ? vp_synchronize_vectors+0x60/0x60
-[   62.492121]  vp_notify+0x12/0x20
-[   62.492121]  virtqueue_notify+0x18/0x30
-[   62.492121]  virtio_queue_rq+0x2f5/0x300 [virtio_blk]
-[   62.492121]  blk_mq_dispatch_rq_list+0x7e/0x4a0
-[   62.492121]  blk_mq_do_dispatch_sched+0x4a/0xd0
-[   62.492121]  blk_mq_sched_dispatch_requests+0x106/0x170
-[   62.492121]  __blk_mq_run_hw_queue+0x80/0x90
-[   62.492121]  process_one_work+0x1e3/0x420
-[   62.492121]  worker_thread+0x2b/0x3d0
-[   62.492121]  ? process_one_work+0x420/0x420
-[   62.492121]  kthread+0x113/0x130
-[   62.492121]  ? kthread_create_worker_on_cpu+0x50/0x50
-[   62.492121]  ret_from_fork+0x3a/0x50
-[   62.492121] kworker/0:0H    R  running task        0     4      2 0x80000000
-[   62.492121] Workqueue: kblockd blk_mq_run_work_fn
-[   62.492121] Call Trace:
-[   62.492121]  <IRQ>
-[   62.492121]  sched_show_task+0xdf/0x100
-[   62.492121]  rcu_print_detail_task_stall_rnp+0x48/0x69
-[   62.492121]  rcu_check_callbacks+0x972/0x9d0
-[   62.492121]  ? tick_sched_do_timer+0x40/0x40
-[   62.492121]  update_process_times+0x28/0x50
-[   62.492121]  tick_sched_handle+0x22/0x70
-[   62.492121]  tick_sched_timer+0x34/0x70
-[   62.492121]  __hrtimer_run_queues+0xcc/0x250
-[   62.492121]  hrtimer_interrupt+0xab/0x1f0
-[   62.492121]  smp_apic_timer_interrupt+0x62/0x150
-[   62.492121]  apic_timer_interrupt+0xa2/0xb0
-[   62.492121]  </IRQ>
-[   62.492121] RIP: 0010:iowrite16+0x1d/0x30
-[   62.492121] RSP: 0018:ffffa477c034fcc8 EFLAGS: 00010292 ORIG_RAX: ffffffffffffff11
-[   62.492121] RAX: ffffffffa24fbdb0 RBX: ffff92a1f8f82000 RCX: 0000000000000001
-[   62.492121] RDX: ffffa477c0371000 RSI: ffffa477c0371000 RDI: 0000000000000000
-[   62.492121] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000001080020
-[   62.492121] R10: ffffdc7cc1e4fc00 R11: 0000000000000000 R12: 0000000000000000
-[   62.492121] R13: 0000000000000000 R14: ffff92a1f93f0000 R15: ffff92a1f8e1aa80
-[   62.492121]  ? vp_synchronize_vectors+0x60/0x60
-[   62.492121]  vp_notify+0x12/0x20
-[   62.492121]  virtqueue_notify+0x18/0x30
-[   62.492121]  virtio_queue_rq+0x2f5/0x300 [virtio_blk]
-[   62.492121]  blk_mq_dispatch_rq_list+0x7e/0x4a0
-[   62.492121]  blk_mq_do_dispatch_sched+0x4a/0xd0
-[   62.492121]  blk_mq_sched_dispatch_requests+0x106/0x170
-[   62.492121]  __blk_mq_run_hw_queue+0x80/0x90
-[   62.492121]  process_one_work+0x1e3/0x420
-[   62.492121]  worker_thread+0x2b/0x3d0
-[   62.492121]  ? process_one_work+0x420/0x420
-[   62.492121]  kthread+0x113/0x130
-[   62.492121]  ? kthread_create_worker_on_cpu+0x50/0x50
-[   62.492121]  ret_from_fork+0x3a/0x50
-
-Another important thing is that the commit works well on other hardware with the same setup (same host kernel, same qemu command line and host kernel binaries). How could I try to find the issue reason?
-
-
-
-
-
-
-
-Well, I've found that on qemu side VirtQueue for virtio_blk device
-infinitely calls virtio_blk_handle_vq() where virtio_blk_get_request()
-(virtqueue_pop() in essens) always returns NULL.
-
-2018-02-18 15:26 GMT+03:00 Matwey V. Kornilov <email address hidden>:
-> ** Attachment added: ".build.kernel.kvm"
->    https://bugs.launchpad.net/qemu/+bug/1750229/+attachment/5057653/+files/.build.kernel.kvm
->
-> --
-> You received this bug notification because you are subscribed to the bug
-> report.
-> https://bugs.launchpad.net/bugs/1750229
->
-> Title:
->   virtio-blk-pci regression: softlock in guest kernel at module loading
->
-> Status in QEMU:
->   New
->
-> Bug description:
->   Hello,
->
->   I am running qemu from master git branch on x86_64 host with kernel is
->   4.4.114. I've found that commit
->
->       9a4c0e220d8a "hw/virtio-pci: fix virtio behaviour"
->
->   introduces an regression with the following command:
->
->       qemu-system-x86_64 -enable-kvm -nodefaults -no-reboot -nographic
->   -vga none -runas qemu -kernel .build.kernel.kvm -initrd
->   .build.initrd.kvm -append 'panic=1 softlockup_panic=1 no-kvmclock
->   nmi_watchdog=0 console=ttyS0 root=/dev/disk/by-id/virtio-0' -m 2048
->   -drive file=./root,format=raw,if=none,id=disk,serial=0,cache=unsafe
->   -device virtio-blk-pci,drive=disk -serial stdio -smp 2
->
->   Starting from this commit to master the following happens with a wide
->   variety of guest kernels (4.4 to 4.15):
->
->   [   62.428107] BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=-20 stuck for 59s!
->   [   62.437426] Showing busy workqueues and worker pools:
->   [   62.443117] workqueue events: flags=0x0
->   [   62.447512]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
->   [   62.448161]     pending: check_corruption
->   [   62.458570] workqueue kblockd: flags=0x18
->   [   62.463082]   pwq 1: cpus=0 node=0 flags=0x0 nice=-20 active=3/256
->   [   62.463082]     in-flight: 4:blk_mq_run_work_fn
->   [   62.463082]     pending: blk_mq_run_work_fn, blk_mq_timeout_work
->   [   62.474831] pool 1: cpus=0 node=0 flags=0x0 nice=-20 hung=59s workers=2 idle: 214
->   [   62.492121] INFO: rcu_preempt detected stalls on CPUs/tasks:
->   [   62.492121]  Tasks blocked on level-0 rcu_node (CPUs 0-1): P4
->   [   62.492121]  (detected by 0, t=15002 jiffies, g=-130, c=-131, q=32)
->   [   62.492121] kworker/0:0H    R  running task        0     4      2 0x80000000
->   [   62.492121] Workqueue: kblockd blk_mq_run_work_fn
->   [   62.492121] Call Trace:
->   [   62.492121]  <IRQ>
->   [   62.492121]  sched_show_task+0xdf/0x100
->   [   62.492121]  rcu_print_detail_task_stall_rnp+0x48/0x69
->   [   62.492121]  rcu_check_callbacks+0x93d/0x9d0
->   [   62.492121]  ? tick_sched_do_timer+0x40/0x40
->   [   62.492121]  update_process_times+0x28/0x50
->   [   62.492121]  tick_sched_handle+0x22/0x70
->   [   62.492121]  tick_sched_timer+0x34/0x70
->   [   62.492121]  __hrtimer_run_queues+0xcc/0x250
->   [   62.492121]  hrtimer_interrupt+0xab/0x1f0
->   [   62.492121]  smp_apic_timer_interrupt+0x62/0x150
->   [   62.492121]  apic_timer_interrupt+0xa2/0xb0
->   [   62.492121]  </IRQ>
->   [   62.492121] RIP: 0010:iowrite16+0x1d/0x30
->   [   62.492121] RSP: 0018:ffffa477c034fcc8 EFLAGS: 00010292 ORIG_RAX: ffffffffffffff11
->   [   62.492121] RAX: ffffffffa24fbdb0 RBX: ffff92a1f8f82000 RCX: 0000000000000001
->   [   62.492121] RDX: ffffa477c0371000 RSI: ffffa477c0371000 RDI: 0000000000000000
->   [   62.492121] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000001080020
->   [   62.492121] R10: ffffdc7cc1e4fc00 R11: 0000000000000000 R12: 0000000000000000
->   [   62.492121] R13: 0000000000000000 R14: ffff92a1f93f0000 R15: ffff92a1f8e1aa80
->   [   62.492121]  ? vp_synchronize_vectors+0x60/0x60
->   [   62.492121]  vp_notify+0x12/0x20
->   [   62.492121]  virtqueue_notify+0x18/0x30
->   [   62.492121]  virtio_queue_rq+0x2f5/0x300 [virtio_blk]
->   [   62.492121]  blk_mq_dispatch_rq_list+0x7e/0x4a0
->   [   62.492121]  blk_mq_do_dispatch_sched+0x4a/0xd0
->   [   62.492121]  blk_mq_sched_dispatch_requests+0x106/0x170
->   [   62.492121]  __blk_mq_run_hw_queue+0x80/0x90
->   [   62.492121]  process_one_work+0x1e3/0x420
->   [   62.492121]  worker_thread+0x2b/0x3d0
->   [   62.492121]  ? process_one_work+0x420/0x420
->   [   62.492121]  kthread+0x113/0x130
->   [   62.492121]  ? kthread_create_worker_on_cpu+0x50/0x50
->   [   62.492121]  ret_from_fork+0x3a/0x50
->   [   62.492121] kworker/0:0H    R  running task        0     4      2 0x80000000
->   [   62.492121] Workqueue: kblockd blk_mq_run_work_fn
->   [   62.492121] Call Trace:
->   [   62.492121]  <IRQ>
->   [   62.492121]  sched_show_task+0xdf/0x100
->   [   62.492121]  rcu_print_detail_task_stall_rnp+0x48/0x69
->   [   62.492121]  rcu_check_callbacks+0x972/0x9d0
->   [   62.492121]  ? tick_sched_do_timer+0x40/0x40
->   [   62.492121]  update_process_times+0x28/0x50
->   [   62.492121]  tick_sched_handle+0x22/0x70
->   [   62.492121]  tick_sched_timer+0x34/0x70
->   [   62.492121]  __hrtimer_run_queues+0xcc/0x250
->   [   62.492121]  hrtimer_interrupt+0xab/0x1f0
->   [   62.492121]  smp_apic_timer_interrupt+0x62/0x150
->   [   62.492121]  apic_timer_interrupt+0xa2/0xb0
->   [   62.492121]  </IRQ>
->   [   62.492121] RIP: 0010:iowrite16+0x1d/0x30
->   [   62.492121] RSP: 0018:ffffa477c034fcc8 EFLAGS: 00010292 ORIG_RAX: ffffffffffffff11
->   [   62.492121] RAX: ffffffffa24fbdb0 RBX: ffff92a1f8f82000 RCX: 0000000000000001
->   [   62.492121] RDX: ffffa477c0371000 RSI: ffffa477c0371000 RDI: 0000000000000000
->   [   62.492121] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000001080020
->   [   62.492121] R10: ffffdc7cc1e4fc00 R11: 0000000000000000 R12: 0000000000000000
->   [   62.492121] R13: 0000000000000000 R14: ffff92a1f93f0000 R15: ffff92a1f8e1aa80
->   [   62.492121]  ? vp_synchronize_vectors+0x60/0x60
->   [   62.492121]  vp_notify+0x12/0x20
->   [   62.492121]  virtqueue_notify+0x18/0x30
->   [   62.492121]  virtio_queue_rq+0x2f5/0x300 [virtio_blk]
->   [   62.492121]  blk_mq_dispatch_rq_list+0x7e/0x4a0
->   [   62.492121]  blk_mq_do_dispatch_sched+0x4a/0xd0
->   [   62.492121]  blk_mq_sched_dispatch_requests+0x106/0x170
->   [   62.492121]  __blk_mq_run_hw_queue+0x80/0x90
->   [   62.492121]  process_one_work+0x1e3/0x420
->   [   62.492121]  worker_thread+0x2b/0x3d0
->   [   62.492121]  ? process_one_work+0x420/0x420
->   [   62.492121]  kthread+0x113/0x130
->   [   62.492121]  ? kthread_create_worker_on_cpu+0x50/0x50
->   [   62.492121]  ret_from_fork+0x3a/0x50
->
->   Another important thing is that the commit works well on other
->   hardware with the same setup (same host kernel, same qemu command line
->   and host kernel binaries). How could I try to find the issue reason?
->
-> To manage notifications about this bug go to:
-> https://bugs.launchpad.net/qemu/+bug/1750229/+subscriptions
-
-
-
--- 
-With best regards,
-Matwey V. Kornilov
-
-
-virtqueue_pop() returns NULL due to virtio_queue_empty_rcu() returns
-true all the time.
-
-2018-02-20 14:47 GMT+03:00 Matwey V. Kornilov <email address hidden>:
-> Well, I've found that on qemu side VirtQueue for virtio_blk device
-> infinitely calls virtio_blk_handle_vq() where virtio_blk_get_request()
-> (virtqueue_pop() in essens) always returns NULL.
->
-> 2018-02-18 15:26 GMT+03:00 Matwey V. Kornilov <email address hidden>:
->> ** Attachment added: ".build.kernel.kvm"
->>    https://bugs.launchpad.net/qemu/+bug/1750229/+attachment/5057653/+files/.build.kernel.kvm
->>
->> --
->> You received this bug notification because you are subscribed to the bug
->> report.
->> https://bugs.launchpad.net/bugs/1750229
->>
->> Title:
->>   virtio-blk-pci regression: softlock in guest kernel at module loading
->>
->> Status in QEMU:
->>   New
->>
->> Bug description:
->>   Hello,
->>
->>   I am running qemu from master git branch on x86_64 host with kernel is
->>   4.4.114. I've found that commit
->>
->>       9a4c0e220d8a "hw/virtio-pci: fix virtio behaviour"
->>
->>   introduces an regression with the following command:
->>
->>       qemu-system-x86_64 -enable-kvm -nodefaults -no-reboot -nographic
->>   -vga none -runas qemu -kernel .build.kernel.kvm -initrd
->>   .build.initrd.kvm -append 'panic=1 softlockup_panic=1 no-kvmclock
->>   nmi_watchdog=0 console=ttyS0 root=/dev/disk/by-id/virtio-0' -m 2048
->>   -drive file=./root,format=raw,if=none,id=disk,serial=0,cache=unsafe
->>   -device virtio-blk-pci,drive=disk -serial stdio -smp 2
->>
->>   Starting from this commit to master the following happens with a wide
->>   variety of guest kernels (4.4 to 4.15):
->>
->>   [   62.428107] BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=-20 stuck for 59s!
->>   [   62.437426] Showing busy workqueues and worker pools:
->>   [   62.443117] workqueue events: flags=0x0
->>   [   62.447512]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
->>   [   62.448161]     pending: check_corruption
->>   [   62.458570] workqueue kblockd: flags=0x18
->>   [   62.463082]   pwq 1: cpus=0 node=0 flags=0x0 nice=-20 active=3/256
->>   [   62.463082]     in-flight: 4:blk_mq_run_work_fn
->>   [   62.463082]     pending: blk_mq_run_work_fn, blk_mq_timeout_work
->>   [   62.474831] pool 1: cpus=0 node=0 flags=0x0 nice=-20 hung=59s workers=2 idle: 214
->>   [   62.492121] INFO: rcu_preempt detected stalls on CPUs/tasks:
->>   [   62.492121]  Tasks blocked on level-0 rcu_node (CPUs 0-1): P4
->>   [   62.492121]  (detected by 0, t=15002 jiffies, g=-130, c=-131, q=32)
->>   [   62.492121] kworker/0:0H    R  running task        0     4      2 0x80000000
->>   [   62.492121] Workqueue: kblockd blk_mq_run_work_fn
->>   [   62.492121] Call Trace:
->>   [   62.492121]  <IRQ>
->>   [   62.492121]  sched_show_task+0xdf/0x100
->>   [   62.492121]  rcu_print_detail_task_stall_rnp+0x48/0x69
->>   [   62.492121]  rcu_check_callbacks+0x93d/0x9d0
->>   [   62.492121]  ? tick_sched_do_timer+0x40/0x40
->>   [   62.492121]  update_process_times+0x28/0x50
->>   [   62.492121]  tick_sched_handle+0x22/0x70
->>   [   62.492121]  tick_sched_timer+0x34/0x70
->>   [   62.492121]  __hrtimer_run_queues+0xcc/0x250
->>   [   62.492121]  hrtimer_interrupt+0xab/0x1f0
->>   [   62.492121]  smp_apic_timer_interrupt+0x62/0x150
->>   [   62.492121]  apic_timer_interrupt+0xa2/0xb0
->>   [   62.492121]  </IRQ>
->>   [   62.492121] RIP: 0010:iowrite16+0x1d/0x30
->>   [   62.492121] RSP: 0018:ffffa477c034fcc8 EFLAGS: 00010292 ORIG_RAX: ffffffffffffff11
->>   [   62.492121] RAX: ffffffffa24fbdb0 RBX: ffff92a1f8f82000 RCX: 0000000000000001
->>   [   62.492121] RDX: ffffa477c0371000 RSI: ffffa477c0371000 RDI: 0000000000000000
->>   [   62.492121] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000001080020
->>   [   62.492121] R10: ffffdc7cc1e4fc00 R11: 0000000000000000 R12: 0000000000000000
->>   [   62.492121] R13: 0000000000000000 R14: ffff92a1f93f0000 R15: ffff92a1f8e1aa80
->>   [   62.492121]  ? vp_synchronize_vectors+0x60/0x60
->>   [   62.492121]  vp_notify+0x12/0x20
->>   [   62.492121]  virtqueue_notify+0x18/0x30
->>   [   62.492121]  virtio_queue_rq+0x2f5/0x300 [virtio_blk]
->>   [   62.492121]  blk_mq_dispatch_rq_list+0x7e/0x4a0
->>   [   62.492121]  blk_mq_do_dispatch_sched+0x4a/0xd0
->>   [   62.492121]  blk_mq_sched_dispatch_requests+0x106/0x170
->>   [   62.492121]  __blk_mq_run_hw_queue+0x80/0x90
->>   [   62.492121]  process_one_work+0x1e3/0x420
->>   [   62.492121]  worker_thread+0x2b/0x3d0
->>   [   62.492121]  ? process_one_work+0x420/0x420
->>   [   62.492121]  kthread+0x113/0x130
->>   [   62.492121]  ? kthread_create_worker_on_cpu+0x50/0x50
->>   [   62.492121]  ret_from_fork+0x3a/0x50
->>   [   62.492121] kworker/0:0H    R  running task        0     4      2 0x80000000
->>   [   62.492121] Workqueue: kblockd blk_mq_run_work_fn
->>   [   62.492121] Call Trace:
->>   [   62.492121]  <IRQ>
->>   [   62.492121]  sched_show_task+0xdf/0x100
->>   [   62.492121]  rcu_print_detail_task_stall_rnp+0x48/0x69
->>   [   62.492121]  rcu_check_callbacks+0x972/0x9d0
->>   [   62.492121]  ? tick_sched_do_timer+0x40/0x40
->>   [   62.492121]  update_process_times+0x28/0x50
->>   [   62.492121]  tick_sched_handle+0x22/0x70
->>   [   62.492121]  tick_sched_timer+0x34/0x70
->>   [   62.492121]  __hrtimer_run_queues+0xcc/0x250
->>   [   62.492121]  hrtimer_interrupt+0xab/0x1f0
->>   [   62.492121]  smp_apic_timer_interrupt+0x62/0x150
->>   [   62.492121]  apic_timer_interrupt+0xa2/0xb0
->>   [   62.492121]  </IRQ>
->>   [   62.492121] RIP: 0010:iowrite16+0x1d/0x30
->>   [   62.492121] RSP: 0018:ffffa477c034fcc8 EFLAGS: 00010292 ORIG_RAX: ffffffffffffff11
->>   [   62.492121] RAX: ffffffffa24fbdb0 RBX: ffff92a1f8f82000 RCX: 0000000000000001
->>   [   62.492121] RDX: ffffa477c0371000 RSI: ffffa477c0371000 RDI: 0000000000000000
->>   [   62.492121] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000001080020
->>   [   62.492121] R10: ffffdc7cc1e4fc00 R11: 0000000000000000 R12: 0000000000000000
->>   [   62.492121] R13: 0000000000000000 R14: ffff92a1f93f0000 R15: ffff92a1f8e1aa80
->>   [   62.492121]  ? vp_synchronize_vectors+0x60/0x60
->>   [   62.492121]  vp_notify+0x12/0x20
->>   [   62.492121]  virtqueue_notify+0x18/0x30
->>   [   62.492121]  virtio_queue_rq+0x2f5/0x300 [virtio_blk]
->>   [   62.492121]  blk_mq_dispatch_rq_list+0x7e/0x4a0
->>   [   62.492121]  blk_mq_do_dispatch_sched+0x4a/0xd0
->>   [   62.492121]  blk_mq_sched_dispatch_requests+0x106/0x170
->>   [   62.492121]  __blk_mq_run_hw_queue+0x80/0x90
->>   [   62.492121]  process_one_work+0x1e3/0x420
->>   [   62.492121]  worker_thread+0x2b/0x3d0
->>   [   62.492121]  ? process_one_work+0x420/0x420
->>   [   62.492121]  kthread+0x113/0x130
->>   [   62.492121]  ? kthread_create_worker_on_cpu+0x50/0x50
->>   [   62.492121]  ret_from_fork+0x3a/0x50
->>
->>   Another important thing is that the commit works well on other
->>   hardware with the same setup (same host kernel, same qemu command line
->>   and host kernel binaries). How could I try to find the issue reason?
->>
->> To manage notifications about this bug go to:
->> https://bugs.launchpad.net/qemu/+bug/1750229/+subscriptions
->
->
->
-> --
-> With best regards,
-> Matwey V. Kornilov
-
-
-
--- 
-With best regards,
-Matwey V. Kornilov
-
-
-Well, last_avail_idx equals to shadow_avail_idx and both of them are 1
-at the qemu side. So, only one request is transferred.
-I wonder why, probably something is badly cached, but new avail_idx
-(which is supposed to become 2) is never shown up.
-
-2018-02-20 15:49 GMT+03:00 Matwey V. Kornilov <email address hidden>:
-> virtqueue_pop() returns NULL due to virtio_queue_empty_rcu() returns
-> true all the time.
->
-> 2018-02-20 14:47 GMT+03:00 Matwey V. Kornilov <email address hidden>:
->> Well, I've found that on qemu side VirtQueue for virtio_blk device
->> infinitely calls virtio_blk_handle_vq() where virtio_blk_get_request()
->> (virtqueue_pop() in essens) always returns NULL.
->>
->> 2018-02-18 15:26 GMT+03:00 Matwey V. Kornilov <email address hidden>:
->>> ** Attachment added: ".build.kernel.kvm"
->>>    https://bugs.launchpad.net/qemu/+bug/1750229/+attachment/5057653/+files/.build.kernel.kvm
->>>
->>> --
->>> You received this bug notification because you are subscribed to the bug
->>> report.
->>> https://bugs.launchpad.net/bugs/1750229
->>>
->>> Title:
->>>   virtio-blk-pci regression: softlock in guest kernel at module loading
->>>
->>> Status in QEMU:
->>>   New
->>>
->>> Bug description:
->>>   Hello,
->>>
->>>   I am running qemu from master git branch on x86_64 host with kernel is
->>>   4.4.114. I've found that commit
->>>
->>>       9a4c0e220d8a "hw/virtio-pci: fix virtio behaviour"
->>>
->>>   introduces an regression with the following command:
->>>
->>>       qemu-system-x86_64 -enable-kvm -nodefaults -no-reboot -nographic
->>>   -vga none -runas qemu -kernel .build.kernel.kvm -initrd
->>>   .build.initrd.kvm -append 'panic=1 softlockup_panic=1 no-kvmclock
->>>   nmi_watchdog=0 console=ttyS0 root=/dev/disk/by-id/virtio-0' -m 2048
->>>   -drive file=./root,format=raw,if=none,id=disk,serial=0,cache=unsafe
->>>   -device virtio-blk-pci,drive=disk -serial stdio -smp 2
->>>
->>>   Starting from this commit to master the following happens with a wide
->>>   variety of guest kernels (4.4 to 4.15):
->>>
->>>   [   62.428107] BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=-20 stuck for 59s!
->>>   [   62.437426] Showing busy workqueues and worker pools:
->>>   [   62.443117] workqueue events: flags=0x0
->>>   [   62.447512]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
->>>   [   62.448161]     pending: check_corruption
->>>   [   62.458570] workqueue kblockd: flags=0x18
->>>   [   62.463082]   pwq 1: cpus=0 node=0 flags=0x0 nice=-20 active=3/256
->>>   [   62.463082]     in-flight: 4:blk_mq_run_work_fn
->>>   [   62.463082]     pending: blk_mq_run_work_fn, blk_mq_timeout_work
->>>   [   62.474831] pool 1: cpus=0 node=0 flags=0x0 nice=-20 hung=59s workers=2 idle: 214
->>>   [   62.492121] INFO: rcu_preempt detected stalls on CPUs/tasks:
->>>   [   62.492121]  Tasks blocked on level-0 rcu_node (CPUs 0-1): P4
->>>   [   62.492121]  (detected by 0, t=15002 jiffies, g=-130, c=-131, q=32)
->>>   [   62.492121] kworker/0:0H    R  running task        0     4      2 0x80000000
->>>   [   62.492121] Workqueue: kblockd blk_mq_run_work_fn
->>>   [   62.492121] Call Trace:
->>>   [   62.492121]  <IRQ>
->>>   [   62.492121]  sched_show_task+0xdf/0x100
->>>   [   62.492121]  rcu_print_detail_task_stall_rnp+0x48/0x69
->>>   [   62.492121]  rcu_check_callbacks+0x93d/0x9d0
->>>   [   62.492121]  ? tick_sched_do_timer+0x40/0x40
->>>   [   62.492121]  update_process_times+0x28/0x50
->>>   [   62.492121]  tick_sched_handle+0x22/0x70
->>>   [   62.492121]  tick_sched_timer+0x34/0x70
->>>   [   62.492121]  __hrtimer_run_queues+0xcc/0x250
->>>   [   62.492121]  hrtimer_interrupt+0xab/0x1f0
->>>   [   62.492121]  smp_apic_timer_interrupt+0x62/0x150
->>>   [   62.492121]  apic_timer_interrupt+0xa2/0xb0
->>>   [   62.492121]  </IRQ>
->>>   [   62.492121] RIP: 0010:iowrite16+0x1d/0x30
->>>   [   62.492121] RSP: 0018:ffffa477c034fcc8 EFLAGS: 00010292 ORIG_RAX: ffffffffffffff11
->>>   [   62.492121] RAX: ffffffffa24fbdb0 RBX: ffff92a1f8f82000 RCX: 0000000000000001
->>>   [   62.492121] RDX: ffffa477c0371000 RSI: ffffa477c0371000 RDI: 0000000000000000
->>>   [   62.492121] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000001080020
->>>   [   62.492121] R10: ffffdc7cc1e4fc00 R11: 0000000000000000 R12: 0000000000000000
->>>   [   62.492121] R13: 0000000000000000 R14: ffff92a1f93f0000 R15: ffff92a1f8e1aa80
->>>   [   62.492121]  ? vp_synchronize_vectors+0x60/0x60
->>>   [   62.492121]  vp_notify+0x12/0x20
->>>   [   62.492121]  virtqueue_notify+0x18/0x30
->>>   [   62.492121]  virtio_queue_rq+0x2f5/0x300 [virtio_blk]
->>>   [   62.492121]  blk_mq_dispatch_rq_list+0x7e/0x4a0
->>>   [   62.492121]  blk_mq_do_dispatch_sched+0x4a/0xd0
->>>   [   62.492121]  blk_mq_sched_dispatch_requests+0x106/0x170
->>>   [   62.492121]  __blk_mq_run_hw_queue+0x80/0x90
->>>   [   62.492121]  process_one_work+0x1e3/0x420
->>>   [   62.492121]  worker_thread+0x2b/0x3d0
->>>   [   62.492121]  ? process_one_work+0x420/0x420
->>>   [   62.492121]  kthread+0x113/0x130
->>>   [   62.492121]  ? kthread_create_worker_on_cpu+0x50/0x50
->>>   [   62.492121]  ret_from_fork+0x3a/0x50
->>>   [   62.492121] kworker/0:0H    R  running task        0     4      2 0x80000000
->>>   [   62.492121] Workqueue: kblockd blk_mq_run_work_fn
->>>   [   62.492121] Call Trace:
->>>   [   62.492121]  <IRQ>
->>>   [   62.492121]  sched_show_task+0xdf/0x100
->>>   [   62.492121]  rcu_print_detail_task_stall_rnp+0x48/0x69
->>>   [   62.492121]  rcu_check_callbacks+0x972/0x9d0
->>>   [   62.492121]  ? tick_sched_do_timer+0x40/0x40
->>>   [   62.492121]  update_process_times+0x28/0x50
->>>   [   62.492121]  tick_sched_handle+0x22/0x70
->>>   [   62.492121]  tick_sched_timer+0x34/0x70
->>>   [   62.492121]  __hrtimer_run_queues+0xcc/0x250
->>>   [   62.492121]  hrtimer_interrupt+0xab/0x1f0
->>>   [   62.492121]  smp_apic_timer_interrupt+0x62/0x150
->>>   [   62.492121]  apic_timer_interrupt+0xa2/0xb0
->>>   [   62.492121]  </IRQ>
->>>   [   62.492121] RIP: 0010:iowrite16+0x1d/0x30
->>>   [   62.492121] RSP: 0018:ffffa477c034fcc8 EFLAGS: 00010292 ORIG_RAX: ffffffffffffff11
->>>   [   62.492121] RAX: ffffffffa24fbdb0 RBX: ffff92a1f8f82000 RCX: 0000000000000001
->>>   [   62.492121] RDX: ffffa477c0371000 RSI: ffffa477c0371000 RDI: 0000000000000000
->>>   [   62.492121] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000001080020
->>>   [   62.492121] R10: ffffdc7cc1e4fc00 R11: 0000000000000000 R12: 0000000000000000
->>>   [   62.492121] R13: 0000000000000000 R14: ffff92a1f93f0000 R15: ffff92a1f8e1aa80
->>>   [   62.492121]  ? vp_synchronize_vectors+0x60/0x60
->>>   [   62.492121]  vp_notify+0x12/0x20
->>>   [   62.492121]  virtqueue_notify+0x18/0x30
->>>   [   62.492121]  virtio_queue_rq+0x2f5/0x300 [virtio_blk]
->>>   [   62.492121]  blk_mq_dispatch_rq_list+0x7e/0x4a0
->>>   [   62.492121]  blk_mq_do_dispatch_sched+0x4a/0xd0
->>>   [   62.492121]  blk_mq_sched_dispatch_requests+0x106/0x170
->>>   [   62.492121]  __blk_mq_run_hw_queue+0x80/0x90
->>>   [   62.492121]  process_one_work+0x1e3/0x420
->>>   [   62.492121]  worker_thread+0x2b/0x3d0
->>>   [   62.492121]  ? process_one_work+0x420/0x420
->>>   [   62.492121]  kthread+0x113/0x130
->>>   [   62.492121]  ? kthread_create_worker_on_cpu+0x50/0x50
->>>   [   62.492121]  ret_from_fork+0x3a/0x50
->>>
->>>   Another important thing is that the commit works well on other
->>>   hardware with the same setup (same host kernel, same qemu command line
->>>   and host kernel binaries). How could I try to find the issue reason?
->>>
->>> To manage notifications about this bug go to:
->>> https://bugs.launchpad.net/qemu/+bug/1750229/+subscriptions
->>
->>
->>
->> --
->> With best regards,
->> Matwey V. Kornilov
->
->
->
-> --
-> With best regards,
-> Matwey V. Kornilov
-
-
-
--- 
-With best regards,
-Matwey V. Kornilov
-
-
-The same story with 4.15.4 host kernel.
-
-2018-02-21 11:58 GMT+03:00 Matwey V. Kornilov <email address hidden>:
-> Well, last_avail_idx equals to shadow_avail_idx and both of them are 1
-> at the qemu side. So, only one request is transferred.
-> I wonder why, probably something is badly cached, but new avail_idx
-> (which is supposed to become 2) is never shown up.
->
-> 2018-02-20 15:49 GMT+03:00 Matwey V. Kornilov <email address hidden>:
->> virtqueue_pop() returns NULL due to virtio_queue_empty_rcu() returns
->> true all the time.
->>
->> 2018-02-20 14:47 GMT+03:00 Matwey V. Kornilov <email address hidden>:
->>> Well, I've found that on qemu side VirtQueue for virtio_blk device
->>> infinitely calls virtio_blk_handle_vq() where virtio_blk_get_request()
->>> (virtqueue_pop() in essens) always returns NULL.
->>>
->>> 2018-02-18 15:26 GMT+03:00 Matwey V. Kornilov <email address hidden>:
->>>> ** Attachment added: ".build.kernel.kvm"
->>>>    https://bugs.launchpad.net/qemu/+bug/1750229/+attachment/5057653/+files/.build.kernel.kvm
->>>>
->>>> --
->>>> You received this bug notification because you are subscribed to the bug
->>>> report.
->>>> https://bugs.launchpad.net/bugs/1750229
->>>>
->>>> Title:
->>>>   virtio-blk-pci regression: softlock in guest kernel at module loading
->>>>
->>>> Status in QEMU:
->>>>   New
->>>>
->>>> Bug description:
->>>>   Hello,
->>>>
->>>>   I am running qemu from master git branch on x86_64 host with kernel is
->>>>   4.4.114. I've found that commit
->>>>
->>>>       9a4c0e220d8a "hw/virtio-pci: fix virtio behaviour"
->>>>
->>>>   introduces an regression with the following command:
->>>>
->>>>       qemu-system-x86_64 -enable-kvm -nodefaults -no-reboot -nographic
->>>>   -vga none -runas qemu -kernel .build.kernel.kvm -initrd
->>>>   .build.initrd.kvm -append 'panic=1 softlockup_panic=1 no-kvmclock
->>>>   nmi_watchdog=0 console=ttyS0 root=/dev/disk/by-id/virtio-0' -m 2048
->>>>   -drive file=./root,format=raw,if=none,id=disk,serial=0,cache=unsafe
->>>>   -device virtio-blk-pci,drive=disk -serial stdio -smp 2
->>>>
->>>>   Starting from this commit to master the following happens with a wide
->>>>   variety of guest kernels (4.4 to 4.15):
->>>>
->>>>   [   62.428107] BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=-20 stuck for 59s!
->>>>   [   62.437426] Showing busy workqueues and worker pools:
->>>>   [   62.443117] workqueue events: flags=0x0
->>>>   [   62.447512]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
->>>>   [   62.448161]     pending: check_corruption
->>>>   [   62.458570] workqueue kblockd: flags=0x18
->>>>   [   62.463082]   pwq 1: cpus=0 node=0 flags=0x0 nice=-20 active=3/256
->>>>   [   62.463082]     in-flight: 4:blk_mq_run_work_fn
->>>>   [   62.463082]     pending: blk_mq_run_work_fn, blk_mq_timeout_work
->>>>   [   62.474831] pool 1: cpus=0 node=0 flags=0x0 nice=-20 hung=59s workers=2 idle: 214
->>>>   [   62.492121] INFO: rcu_preempt detected stalls on CPUs/tasks:
->>>>   [   62.492121]  Tasks blocked on level-0 rcu_node (CPUs 0-1): P4
->>>>   [   62.492121]  (detected by 0, t=15002 jiffies, g=-130, c=-131, q=32)
->>>>   [   62.492121] kworker/0:0H    R  running task        0     4      2 0x80000000
->>>>   [   62.492121] Workqueue: kblockd blk_mq_run_work_fn
->>>>   [   62.492121] Call Trace:
->>>>   [   62.492121]  <IRQ>
->>>>   [   62.492121]  sched_show_task+0xdf/0x100
->>>>   [   62.492121]  rcu_print_detail_task_stall_rnp+0x48/0x69
->>>>   [   62.492121]  rcu_check_callbacks+0x93d/0x9d0
->>>>   [   62.492121]  ? tick_sched_do_timer+0x40/0x40
->>>>   [   62.492121]  update_process_times+0x28/0x50
->>>>   [   62.492121]  tick_sched_handle+0x22/0x70
->>>>   [   62.492121]  tick_sched_timer+0x34/0x70
->>>>   [   62.492121]  __hrtimer_run_queues+0xcc/0x250
->>>>   [   62.492121]  hrtimer_interrupt+0xab/0x1f0
->>>>   [   62.492121]  smp_apic_timer_interrupt+0x62/0x150
->>>>   [   62.492121]  apic_timer_interrupt+0xa2/0xb0
->>>>   [   62.492121]  </IRQ>
->>>>   [   62.492121] RIP: 0010:iowrite16+0x1d/0x30
->>>>   [   62.492121] RSP: 0018:ffffa477c034fcc8 EFLAGS: 00010292 ORIG_RAX: ffffffffffffff11
->>>>   [   62.492121] RAX: ffffffffa24fbdb0 RBX: ffff92a1f8f82000 RCX: 0000000000000001
->>>>   [   62.492121] RDX: ffffa477c0371000 RSI: ffffa477c0371000 RDI: 0000000000000000
->>>>   [   62.492121] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000001080020
->>>>   [   62.492121] R10: ffffdc7cc1e4fc00 R11: 0000000000000000 R12: 0000000000000000
->>>>   [   62.492121] R13: 0000000000000000 R14: ffff92a1f93f0000 R15: ffff92a1f8e1aa80
->>>>   [   62.492121]  ? vp_synchronize_vectors+0x60/0x60
->>>>   [   62.492121]  vp_notify+0x12/0x20
->>>>   [   62.492121]  virtqueue_notify+0x18/0x30
->>>>   [   62.492121]  virtio_queue_rq+0x2f5/0x300 [virtio_blk]
->>>>   [   62.492121]  blk_mq_dispatch_rq_list+0x7e/0x4a0
->>>>   [   62.492121]  blk_mq_do_dispatch_sched+0x4a/0xd0
->>>>   [   62.492121]  blk_mq_sched_dispatch_requests+0x106/0x170
->>>>   [   62.492121]  __blk_mq_run_hw_queue+0x80/0x90
->>>>   [   62.492121]  process_one_work+0x1e3/0x420
->>>>   [   62.492121]  worker_thread+0x2b/0x3d0
->>>>   [   62.492121]  ? process_one_work+0x420/0x420
->>>>   [   62.492121]  kthread+0x113/0x130
->>>>   [   62.492121]  ? kthread_create_worker_on_cpu+0x50/0x50
->>>>   [   62.492121]  ret_from_fork+0x3a/0x50
->>>>   [   62.492121] kworker/0:0H    R  running task        0     4      2 0x80000000
->>>>   [   62.492121] Workqueue: kblockd blk_mq_run_work_fn
->>>>   [   62.492121] Call Trace:
->>>>   [   62.492121]  <IRQ>
->>>>   [   62.492121]  sched_show_task+0xdf/0x100
->>>>   [   62.492121]  rcu_print_detail_task_stall_rnp+0x48/0x69
->>>>   [   62.492121]  rcu_check_callbacks+0x972/0x9d0
->>>>   [   62.492121]  ? tick_sched_do_timer+0x40/0x40
->>>>   [   62.492121]  update_process_times+0x28/0x50
->>>>   [   62.492121]  tick_sched_handle+0x22/0x70
->>>>   [   62.492121]  tick_sched_timer+0x34/0x70
->>>>   [   62.492121]  __hrtimer_run_queues+0xcc/0x250
->>>>   [   62.492121]  hrtimer_interrupt+0xab/0x1f0
->>>>   [   62.492121]  smp_apic_timer_interrupt+0x62/0x150
->>>>   [   62.492121]  apic_timer_interrupt+0xa2/0xb0
->>>>   [   62.492121]  </IRQ>
->>>>   [   62.492121] RIP: 0010:iowrite16+0x1d/0x30
->>>>   [   62.492121] RSP: 0018:ffffa477c034fcc8 EFLAGS: 00010292 ORIG_RAX: ffffffffffffff11
->>>>   [   62.492121] RAX: ffffffffa24fbdb0 RBX: ffff92a1f8f82000 RCX: 0000000000000001
->>>>   [   62.492121] RDX: ffffa477c0371000 RSI: ffffa477c0371000 RDI: 0000000000000000
->>>>   [   62.492121] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000001080020
->>>>   [   62.492121] R10: ffffdc7cc1e4fc00 R11: 0000000000000000 R12: 0000000000000000
->>>>   [   62.492121] R13: 0000000000000000 R14: ffff92a1f93f0000 R15: ffff92a1f8e1aa80
->>>>   [   62.492121]  ? vp_synchronize_vectors+0x60/0x60
->>>>   [   62.492121]  vp_notify+0x12/0x20
->>>>   [   62.492121]  virtqueue_notify+0x18/0x30
->>>>   [   62.492121]  virtio_queue_rq+0x2f5/0x300 [virtio_blk]
->>>>   [   62.492121]  blk_mq_dispatch_rq_list+0x7e/0x4a0
->>>>   [   62.492121]  blk_mq_do_dispatch_sched+0x4a/0xd0
->>>>   [   62.492121]  blk_mq_sched_dispatch_requests+0x106/0x170
->>>>   [   62.492121]  __blk_mq_run_hw_queue+0x80/0x90
->>>>   [   62.492121]  process_one_work+0x1e3/0x420
->>>>   [   62.492121]  worker_thread+0x2b/0x3d0
->>>>   [   62.492121]  ? process_one_work+0x420/0x420
->>>>   [   62.492121]  kthread+0x113/0x130
->>>>   [   62.492121]  ? kthread_create_worker_on_cpu+0x50/0x50
->>>>   [   62.492121]  ret_from_fork+0x3a/0x50
->>>>
->>>>   Another important thing is that the commit works well on other
->>>>   hardware with the same setup (same host kernel, same qemu command line
->>>>   and host kernel binaries). How could I try to find the issue reason?
->>>>
->>>> To manage notifications about this bug go to:
->>>> https://bugs.launchpad.net/qemu/+bug/1750229/+subscriptions
->>>
->>>
->>>
->>> --
->>> With best regards,
->>> Matwey V. Kornilov
->>
->>
->>
->> --
->> With best regards,
->> Matwey V. Kornilov
->
->
->
-> --
-> With best regards,
-> Matwey V. Kornilov
-
-
-
--- 
-With best regards,
-Matwey V. Kornilov
-
-
-This has been fixed in the kernel
-
-