Bug 217350

Summary: kdump kernel hangs in powerkvm guest
Product: Platform Specific/Hardware Reporter: Pingfan (piliu)
Component: PPC-64Assignee: platform_ppc-64
Status: NEW ---    
Severity: normal CC: clg, coiby.xu
Priority: P3    
Hardware: PPC-64   
OS: Linux   
Kernel Version: Subsystem:
Regression: No Bisected commit-id:
Attachments: The xml to configure the virtual machine

Description Pingfan 2023-04-18 13:11:49 UTC
Created attachment 304157 [details]
The xml to configure the virtual machine

This bug has been observed at least since kernel version 5.19.

The kdump kernel command line:
[    0.000000] Kernel command line: elfcorehdr=0x22c00000  no_timer_check net.ifnames=0 console=tty0 console=hvc0,115200n8  irqpoll maxcpus=1 noirqdistrib reset_devices cgroup_disable=memory
     numa=off udev.children-max=2 ehea.use_mcs=0 panic=10 kvm_cma_resv_ratio=0 transparent_hugepage=never novmcoredd hugetlb_cma=0 


Finally, the system hangs:
    [    7.763260] virtio_blk virtio2: 32/0/0 default/read/poll queues
    [    7.771391] virtio_blk virtio2: [vda] 20971520 512-byte logical blocks (10.7 GB/10.0 GiB)
    [   68.398234] systemd-udevd[187]: virtio2: Worker [190] processing SEQNUM=1193 is taking a long time
    [  188.398258] systemd-udevd[187]: virtio2: Worker [190] processing SEQNUM=1193 killed
Comment 1 Coiby 2023-05-09 09:33:27 UTC
Hi Cédric,

My bisection [1] shows this is a regression caused by your patch it's a regression caused by "[PATCH 00/31] powerpc: Modernize the PCI/MSI support".  Do you have any suggestion to fix this bug? Thanks!

[1] https://bugzilla.redhat.com/show_bug.cgi?id=2123723
Comment 2 Cédric Le Goater 2023-05-10 17:53:47 UTC
Hello  Pingfan,

This was a large series. Did you identify the exact patch ?  It should be 
related to the powerpc/pseries/pci or powerpc/xive subsystem.