Il giorno ven 26 mag 2023 alle ore 19:01 Sean Christopherson seanjc@google.com ha scritto:
I'm using vanilla kernels on a gentoo-based laptop and since 6.3.2
What was the last kernel you used that didn't trigger this WARN?
6.3.1
I'm getting the kernel log below when using kvm VM on my box.
Are you doing anything "interesting" when the WARN fires, or are you just running the VM and it random fires? Either way, can you provide your QEMU command line?
I'm not able to spot a specific action that triggers the dump. Now it happened when I was "simply" opening a new chrome page in the guest VM. I guess this can cause some work on mm side, but not really an "interesting" action, I'd say. Basically, I fired up the guest machine (ubuntu 22.04 very basic) on a newly rebooted host, connected a USB device (yubikey) and started chrome. No message just after starting chrome, only when I opened a new page.
Anyway, this is the command line (libvirt managed VM)
/usr/sbin/qemu-system-x86_64 -name guest=ubuntu-u2204-kvm,debug-threads=on -S -object {"qom-type":"secret","id":"masterKey0","format":"raw","file":"/var/lib/libvirt/qemu/domain-1-ubuntu-u2204-kvm/master-key.aes"} -blockdev {"driver":"file","filename":"/usr/share/edk2-ovmf/OVMF_CODE.secboot.fd","node-name":"libvirt-pflash0-storage","auto-read-only":true,"discard":"unmap"} -blockdev {"node-name":"libvirt-pflash0-format","read-only":true,"driver":"raw","file":"libvirt-pflash0-storage"} -blockdev {"driver":"file","filename":"/var/lib/libvirt/qemu/nvram/ubuntu-u2204-kvm_VARS.fd","node-name":"libvirt-pflash1-storage","auto-read-only":true,"discard":"unmap"} -blockdev {"node-name":"libvirt-pflash1-format","read-only":false,"driver":"raw","file":"libvirt-pflash1-storage"} -machine pc-q35-7.1,usb=off,vmport=off,smm=on,dump-guest-core=off,memory-backend=pc.ram,pflash0=libvirt-pflash0-format,pflash1=libvirt-pflash1-format,hpet=off,acpi=on -accel kvm -cpu host,migratable=on -global driver=cfi.pflash01,property=secure,value=on -m 16384 -object {"qom-type":"memory-backend-ram","id":"pc.ram","size":17179869184} -overcommit mem-lock=off -smp 4,sockets=4,cores=1,threads=1 -uuid 160141fc-ec2e-4d91-bc1c-3e597643bcfd -no-user-config -nodefaults -chardev socket,id=charmonitor,fd=30,server=on,wait=off -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew -global kvm-pit.lost_tick_policy=delay -no-shutdown -global ICH9-LPC.disable_s3=1 -global ICH9-LPC.disable_s4=1 -boot strict=on -device {"driver":"pcie-root-port","port":16,"chassis":1,"id":"pci.1","bus":"pcie.0","multifunction":true,"addr":"0x2"} -device {"driver":"pcie-root-port","port":17,"chassis":2,"id":"pci.2","bus":"pcie.0","addr":"0x2.0x1"} -device {"driver":"pcie-root-port","port":18,"chassis":3,"id":"pci.3","bus":"pcie.0","addr":"0x2.0x2"} -device {"driver":"pcie-root-port","port":19,"chassis":4,"id":"pci.4","bus":"pcie.0","addr":"0x2.0x3"} -device {"driver":"pcie-root-port","port":20,"chassis":5,"id":"pci.5","bus":"pcie.0","addr":"0x2.0x4"} -device {"driver":"pcie-root-port","port":21,"chassis":6,"id":"pci.6","bus":"pcie.0","addr":"0x2.0x5"} -device {"driver":"pcie-root-port","port":22,"chassis":7,"id":"pci.7","bus":"pcie.0","addr":"0x2.0x6"} -device {"driver":"pcie-root-port","port":23,"chassis":8,"id":"pci.8","bus":"pcie.0","addr":"0x2.0x7"} -device {"driver":"pcie-root-port","port":24,"chassis":9,"id":"pci.9","bus":"pcie.0","multifunction":true,"addr":"0x3"} -device {"driver":"pcie-root-port","port":25,"chassis":10,"id":"pci.10","bus":"pcie.0","addr":"0x3.0x1"} -device {"driver":"pcie-root-port","port":26,"chassis":11,"id":"pci.11","bus":"pcie.0","addr":"0x3.0x2"} -device {"driver":"pcie-root-port","port":27,"chassis":12,"id":"pci.12","bus":"pcie.0","addr":"0x3.0x3"} -device {"driver":"pcie-root-port","port":28,"chassis":13,"id":"pci.13","bus":"pcie.0","addr":"0x3.0x4"} -device {"driver":"pcie-root-port","port":29,"chassis":14,"id":"pci.14","bus":"pcie.0","addr":"0x3.0x5"} -device {"driver":"qemu-xhci","p2":15,"p3":15,"id":"usb","bus":"pci.2","addr":"0x0"} -device {"driver":"virtio-serial-pci","id":"virtio-serial0","bus":"pci.3","addr":"0x0"} -blockdev {"driver":"file","filename":"/var/lib/libvirt/images/ubuntu22.04.qcow2","node-name":"libvirt-2-storage","auto-read-only":true,"discard":"unmap"} -blockdev {"node-name":"libvirt-2-format","read-only":false,"discard":"unmap","driver":"qcow2","file":"libvirt-2-storage","backing":null} -device {"driver":"virtio-blk-pci","bus":"pci.4","addr":"0x0","drive":"libvirt-2-format","id":"virtio-disk0","bootindex":1} -device {"driver":"ide-cd","bus":"ide.0","id":"sata0-0-0"} -netdev {"type":"tap","fd":"32","vhost":true,"vhostfd":"34","id":"hostnet0"} -device {"driver":"virtio-net-pci","netdev":"hostnet0","id":"net0","mac":"52:54:00:17:0a:44","bus":"pci.1","addr":"0x0"} -chardev pty,id=charserial0 -device {"driver":"isa-serial","chardev":"charserial0","id":"serial0","index":0} -chardev socket,id=charchannel0,fd=28,server=on,wait=off -device {"driver":"virtserialport","bus":"virtio-serial0.0","nr":1,"chardev":"charchannel0","id":"channel0","name":"org.qemu.guest_agent.0"} -chardev spicevmc,id=charchannel1,name=vdagent -device {"driver":"virtserialport","bus":"virtio-serial0.0","nr":2,"chardev":"charchannel1","id":"channel1","name":"com.redhat.spice.0"} -device {"driver":"usb-tablet","id":"input0","bus":"usb.0","port":"1"} -audiodev {"id":"audio1","driver":"spice"} -spice port=0,disable-ticketing=on,image-compression=off,seamless-migration=on -device {"driver":"virtio-vga","id":"video0","max_outputs":1,"bus":"pcie.0","addr":"0x1"} -device {"driver":"ich9-intel-hda","id":"sound0","bus":"pcie.0","addr":"0x1b"} -device {"driver":"hda-duplex","id":"sound0-codec0","bus":"sound0.0","cad":0,"audiodev":"audio1"} -global ICH9-LPC.noreboot=off -watchdog-action reset -chardev spicevmc,id=charredir0,name=usbredir -device {"driver":"usb-redir","chardev":"charredir0","id":"redir0","bus":"usb.0","port":"2"} -chardev spicevmc,id=charredir1,name=usbredir -device {"driver":"usb-redir","chardev":"charredir1","id":"redir1","bus":"usb.0","port":"3"} -device {"driver":"virtio-balloon-pci","id":"balloon0","bus":"pci.5","addr":"0x0"} -object {"qom-type":"rng-random","id":"objrng0","filename":"/dev/urandom"} -device {"driver":"virtio-rng-pci","rng":"objrng0","id":"rng0","bus":"pci.6","addr":"0x0"} -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny -msg timestamp=on
ps output (of course a different run from the first message report): 57176 ? I< 0:00 [kvm] 57178 ? S 0:00 [kvm-nx-lpage-recovery-57159] 57189 ? S 0:00 [kvm-pit/57159]
Not sure which other infos can be relevant in this context; if you need more details just let me know, happy to provide them.
[Fri May 26 09:16:35 2023] ------------[ cut here ]------------ [Fri May 26 09:16:35 2023] WARNING: CPU: 5 PID: 4684 at kvm_nx_huge_page_recovery_worker+0x38c/0x3d0 [kvm]
Do you have the actual line number for the WARN? There are a handful of sanity checks in kvm_recover_nx_huge_pages(), it would be helpful to pinpoint which one is firing. My builds generate quite different code, and the code stream doesn't appear to be useful for reverse engineering the location.
That's the full message I get. Maybe I should recompile the host kernel with some debug active, any specific suggestion?