This happened to me today, running kernel 5.3.0-rc3-1.g571863b-default (5.3-rc3 with just a few patches on top), after starting a KVM virtual machine. The X screen was frozen. Remote login via ssh was still possible, thus I was able to retrieve basic logs. sysrq-w showed two blocked processes (kcompactd0 and KVM). After a minute, the same two processes were still blocked. KVM seems to try to acquire a lock that kcompactd is holding. kcompactd is waiting for IO to complete on pages owned by the i915 driver. kcompactd stack: Aug 09 12:12:48 apollon.suse.de kernel: sysrq: Show Blocked State Aug 09 12:12:48 apollon.suse.de kernel: task PC stack pid father Aug 09 12:12:48 apollon.suse.de kernel: kcompactd0 D 0 43 2 0x80004000 Aug 09 12:12:48 apollon.suse.de kernel: Call Trace: Aug 09 12:12:48 apollon.suse.de kernel: ? __schedule+0x2af/0x6a0 Aug 09 12:12:48 apollon.suse.de kernel: schedule+0x33/0x90 Aug 09 12:12:48 apollon.suse.de kernel: io_schedule+0x12/0x40 Aug 09 12:12:48 apollon.suse.de kernel: __lock_page+0x123/0x200 Aug 09 12:12:48 apollon.suse.de kernel: ? gen8_ppgtt_clear_pdp+0xc0/0x140 [i915] Aug 09 12:12:48 apollon.suse.de kernel: ? file_fdatawait_range+0x20/0x20 Aug 09 12:12:48 apollon.suse.de kernel: set_page_dirty_lock+0x49/0x50 Aug 09 12:12:48 apollon.suse.de kernel: i915_gem_userptr_put_pages+0x13f/0x1c0 [i915] Aug 09 12:12:48 apollon.suse.de kernel: __i915_gem_object_put_pages+0x5e/0xa0 [i915] Aug 09 12:12:48 apollon.suse.de kernel: userptr_mn_invalidate_range_start+0x1ff/0x220 [i915] Aug 09 12:12:48 apollon.suse.de kernel: __mmu_notifier_invalidate_range_start+0x57/0xa0 Aug 09 12:12:48 apollon.suse.de kernel: try_to_unmap_one+0xa0b/0xae0 Aug 09 12:12:48 apollon.suse.de kernel: ? __mod_lruvec_state+0x3f/0xf0 Aug 09 12:12:48 apollon.suse.de kernel: rmap_walk_file+0xf2/0x250 Aug 09 12:12:48 apollon.suse.de kernel: try_to_unmap+0xa6/0xe0 Aug 09 12:12:48 apollon.suse.de kernel: ? page_remove_rmap+0x290/0x290 Aug 09 12:12:48 apollon.suse.de kernel: ? page_not_mapped+0x20/0x20 Aug 09 12:12:48 apollon.suse.de kernel: ? page_get_anon_vma+0x80/0x80 Aug 09 12:12:48 apollon.suse.de kernel: migrate_pages+0x8cd/0xbc0 Aug 09 12:12:48 apollon.suse.de kernel: ? fast_isolate_freepages+0x6b0/0x6b0 Aug 09 12:12:48 apollon.suse.de kernel: ? move_freelist_tail+0xb0/0xb0 Aug 09 12:12:48 apollon.suse.de kernel: compact_zone+0x669/0xc80 Aug 09 12:12:48 apollon.suse.de kernel: ? entry_SYSCALL_64_after_hwframe+0xb8/0xbe Aug 09 12:12:48 apollon.suse.de kernel: kcompactd_do_work+0x120/0x290 KVM stack: Aug 09 12:12:48 apollon.suse.de kernel: CPU 0/KVM D 0 25189 1 0x00000320 Aug 09 12:12:48 apollon.suse.de kernel: Call Trace: Aug 09 12:12:48 apollon.suse.de kernel: ? __schedule+0x2af/0x6a0 Aug 09 12:12:48 apollon.suse.de kernel: schedule+0x33/0x90 Aug 09 12:12:48 apollon.suse.de kernel: schedule_preempt_disabled+0xa/0x10 Aug 09 12:12:48 apollon.suse.de kernel: __mutex_lock.isra.0+0x172/0x4d0 Aug 09 12:12:48 apollon.suse.de kernel: userptr_mn_invalidate_range_start+0x1bf/0x220 [i915] Aug 09 12:12:48 apollon.suse.de kernel: __mmu_notifier_invalidate_range_start+0x57/0xa0 Aug 09 12:12:48 apollon.suse.de kernel: try_to_unmap_one+0xa0b/0xae0 Aug 09 12:12:48 apollon.suse.de kernel: rmap_walk_file+0xf2/0x250 Aug 09 12:12:48 apollon.suse.de kernel: try_to_unmap+0xa6/0xe0 Aug 09 12:12:48 apollon.suse.de kernel: ? page_remove_rmap+0x290/0x290 Aug 09 12:12:48 apollon.suse.de kernel: ? page_not_mapped+0x20/0x20 Aug 09 12:12:48 apollon.suse.de kernel: ? page_get_anon_vma+0x80/0x80 Aug 09 12:12:48 apollon.suse.de kernel: migrate_pages+0x8cd/0xbc0 Aug 09 12:12:48 apollon.suse.de kernel: ? fast_isolate_freepages+0x6b0/0x6b0 Aug 09 12:12:48 apollon.suse.de kernel: ? move_freelist_tail+0xb0/0xb0 Aug 09 12:12:48 apollon.suse.de kernel: compact_zone+0x669/0xc80 Aug 09 12:12:48 apollon.suse.de kernel: compact_zone_order+0xc6/0xf0 Aug 09 12:12:48 apollon.suse.de kernel: try_to_compact_pages+0xcc/0x2a0 Aug 09 12:12:48 apollon.suse.de kernel: __alloc_pages_direct_compact+0x7c/0x150 Aug 09 12:12:48 apollon.suse.de kernel: __alloc_pages_slowpath+0x1ee/0xd00 Aug 09 12:12:48 apollon.suse.de kernel: ? vmx_vcpu_load+0x100/0x120 [kvm_intel] Full logs can be found under https://pastebin.com/KJ6tccj4 I haven't yet tried if this is reproducible. Regards Martin _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
