https://bugzilla.kernel.org/show_bug.cgi?id=216388 --- Comment #2 from zhenyuw@xxxxxxxxxxxxxxx --- On 2022.08.22 17:50:33 +0000, Sean Christopherson wrote: > +GVT folks > > On Sun, Aug 21, 2022, bugzilla-daemon@xxxxxxxxxx wrote: > > https://bugzilla.kernel.org/show_bug.cgi?id=216388 > > > > Bug ID: 216388 > > Summary: On Host, kernel errors in KVM, on guests, it shows CPU > > stalls > > Product: Virtualization > > Version: unspecified > > Kernel Version: 5.19.0 / 5.19.1 / 5.19.2 > > Hardware: All > > OS: Linux > > Tree: Mainline > > Status: NEW > > Severity: high > > Priority: P1 > > Component: kvm > > Assignee: virtualization_kvm@xxxxxxxxxxxxxxxxxxxx > > Reporter: nanook@xxxxxxxxxx > > Regression: No > > > > Created attachment 301614 > > --> https://bugzilla.kernel.org/attachment.cgi?id=301614&action=edit > > The configuration file used to Comile this kernel. > > > > This behavior has persisted across 5.19.0, 5.19.1, and 5.19.2. While the > > kernel I am taking this example from is tainted (owing to using Intel > > development drivers for GPU virtualization), it is also occurring on > > non-tainted kernels on servers with no development or third party modules > > installed. > > > > INFO: task CPU 2/KVM:2343 blocked for more than 1228 seconds. > > [207177.050049] Tainted: G U I 5.19.2 #1 > > [207177.050050] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables > > this message. > > [207177.050051] task:CPU 2/KVM state:D stack: 0 pid: 2343 ppid: > 1 > > flags:0x00000002 > > [207177.050054] Call Trace: > > [207177.050055] <TASK> > > [207177.050056] __schedule+0x359/0x1400 > > [207177.050060] ? kvm_mmu_page_fault+0x1ee/0x980 > > [207177.050062] ? kvm_set_msr_common+0x31f/0x1060 > > [207177.050065] schedule+0x5f/0x100 > > [207177.050066] schedule_preempt_disabled+0x15/0x30 > > [207177.050068] __mutex_lock.constprop.0+0x4e2/0x750 > > [207177.050070] ? aa_file_perm+0x124/0x4f0 > > [207177.050071] __mutex_lock_slowpath+0x13/0x20 > > [207177.050072] mutex_lock+0x25/0x30 > > [207177.050075] intel_vgpu_emulate_mmio_read+0x5d/0x3b0 [kvmgt] > > This isn't a KVM problem, it's a KVMGT problem (despite the name, KVMGT is > very > much not KVM). > > > [207177.050084] intel_vgpu_rw+0xb8/0x1c0 [kvmgt] > > [207177.050091] intel_vgpu_read+0x20d/0x250 [kvmgt] > > [207177.050097] vfio_device_fops_read+0x1f/0x40 > > [207177.050100] vfs_read+0x9b/0x160 > > [207177.050102] __x64_sys_pread64+0x93/0xd0 > > [207177.050104] do_syscall_64+0x58/0x80 > > [207177.050106] ? kvm_on_user_return+0x84/0xe0 > > [207177.050107] ? fire_user_return_notifiers+0x37/0x70 > > [207177.050109] ? exit_to_user_mode_prepare+0x41/0x200 > > [207177.050111] ? syscall_exit_to_user_mode+0x1b/0x40 > > [207177.050112] ? do_syscall_64+0x67/0x80 > > [207177.050114] ? irqentry_exit+0x54/0x70 > > [207177.050115] ? sysvec_call_function_single+0x4b/0xa0 > > [207177.050116] entry_SYSCALL_64_after_hwframe+0x63/0xcd > > [207177.050118] RIP: 0033:0x7ff51131293f > > [207177.050119] RSP: 002b:00007ff4ddffa260 EFLAGS: 00000293 ORIG_RAX: > > 0000000000000011 > > [207177.050121] RAX: ffffffffffffffda RBX: 00005599a6835420 RCX: > > 00007ff51131293f > > [207177.050122] RDX: 0000000000000004 RSI: 00007ff4ddffa2a8 RDI: > > 0000000000000027 > > [207177.050123] RBP: 0000000000000004 R08: 0000000000000000 R09: > > 00000000ffffffff > > [207177.050124] R10: 0000000000065f10 R11: 0000000000000293 R12: > > 0000000000065f10 > > [207177.050124] R13: 00005599a6835330 R14: 0000000000000004 R15: > > 0000000000065f10 > > [207177.050126] </TASK> > > > > I am seeing this on Intel i7-6700k, i7-6850k, and i7-9700k platforms. One recent regression fix on Comet Lake is https://patchwork.freedesktop.org/patch/496987/, it's on the way to 6.0-rc and would be pushed to 5.19 stable as well. But looks this report impacts on more platforms? We'll double check. Thanks > > > > This did not happen on 5.17 kernels, and 5.18 kernels never ran stable > > enough on my platforms to actually run them for more than a few minutes. > > > > Likewise 6.0-rc1 has not been stable enough to run in production. > After > > less than three hours running on my workstation it locked hard with even > the > > magic sys-request key being unresponsive and only power cycling the machine > got > > it back. > > > > The operating system in use for the host on all machines is Ubuntu > 22.04. > > > > Guests vary with Ubuntu 22.04 being the most common but also Mint, > Debian, > > Manjaro, Centos, Fedora, ScientificLinux, Zorin, and Windows being in use. > > > > I see the same issue manifest on platforms running only Ubuntu guests > as > > with guests of varying operating systems. > > > > The configuration file I used to compile this kernel is attached. I > > compiled it with gcc 12.1.0. > > > > This behavior does not manifest itself instantly, typically the > machine > > needs to be running 3-7 days before it does. Once it does guests keep > stalling > > and restarting libvirtd does not help. Only thing that seems to is a hard > > reboot of the physical host. For this reason I believe the issue lies > strictly > > with the host and not the guests. > > > > I have listed it as a severity of high since it is completely service > > interrupting. > > > > -- > > You may reply to this email to add a comment. > > > > You are receiving this mail because: > > You are watching the assignee of the bug. -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.