Re: [BUG] Passed through PCI devices lost after Windows HVM DomU reboot

[Jan Beulich <jbeulich@xxxxxxxx>]

On 08.06.2021 01:44, Paul Leiber wrote:
> After more testing, I have come to the following conclusion: It seems that 
> every time I do a _reboot_ from within a Windows DomU, the PCI device does 
> not get attached to the DomU. After DomU reboot, it is immediately available 
> for attachment in the Dom0 when I check for it with "xl pci-assignable-list", 
> and I can reattach it to the DomU with "xl pci-attach" without any major 
> problems beside some annoying side effects (e. g. need to reapply settings).

A well-known problem on ...

> xl info:
> 
> host                   : xxx
> release                : 4.19.0-14-amd64
> version                : #1 SMP Debian 4.19.171-2 (2021-01-30)
> machine                : x86_64
> nr_cpus                : 4
> max_cpu_id             : 3
> nr_nodes               : 1
> cores_per_socket       : 4
> threads_per_core       : 1
> cpu_mhz                : 1992.100
> hw_caps                : 
> bfebfbff:77faf3ff:2c100800:00000121:0000000f:009c6fbf:00000000:00000100
> virt_caps              : hvm hvm_directio
> total_memory           : 32542
> free_memory            : 20836
> sharing_freed_memory   : 0
> sharing_used_memory    : 0
> outstanding_claims     : 0
> free_cpus              : 0
> xen_major              : 4
> xen_minor              : 11
> xen_extra              : .4
> xen_version            : 4.11.4

... this old Xen version, I believe. I don't recall when exactly it was
fixed (and I don't know at all whether the fix was backported), but
trying a recent version of Xen should get you past this. If a fully
maintained version is still affected, a backport could be requested.

Jan