Re: Xen 4.18.4_20241221nb0 panic (Was: Re: EFI and Xen)

[Chuck Zmudzinski <frchuckz%gmail.com@localhost>]

On 5/23/2025 4:22 PM, Manuel Bouyer wrote:
> On Fri, May 23, 2025 at 04:19:46PM -0400, Chuck Zmudzinski wrote:
>> On 5/23/2025 4:15 PM, Manuel Bouyer wrote:
>> > On Fri, May 23, 2025 at 04:13:01PM -0400, Chuck Zmudzinski wrote:
>> >> [...]
>> >> I needed to acquire a PCI serial card to get some useful messages because the motherboard does not have a built-in serial port.
>> >> 
>> >> It appears Xen 4.18.4_20241221nb0 from pkgsrc crashes on my box before the NetBSD dom0 starts:
>> >> 
>> >> -------- snip ------
>> >> (XEN) Xen call trace:
>> >> (XEN)    [<ffff82d040261a00>] R intel_iommu_enable_eim+0/0xe0
>> >> (XEN)    [<ffff82d040268ac4>] S iommu_enable_x2apic+0x24/0x70
>> >> (XEN)    [<ffff82d0403f579d>] S x2apic_bsp_setup+0x12d/0x220
>> >> (XEN)    [<ffff82d0403ff0e4>] S __start_xen+0x1af4/0x2620
>> >> (XEN)    [<ffff82d040204434>] S __high_start+0x94/0xa0
>> >> (XEN) 
>> >> (XEN) 
>> >> (XEN) ****************************************
>> >> (XEN) Panic on CPU 0:
>> >> (XEN) CONTROL-FLOW PROTECTION FAULT: #CP[0003] endbranch
>> >> (XEN) ****************************************
>> >> (XEN) 
>> >> (XEN) Reboot in five seconds...
>> >> (XEN) Resetting with ACPI MEMORY or I/O RESET_REG.
>> >> -------- end messages ------
>> > 
>> > Do you have a way to disable x2apic in the BIOS ?
>> 
>> I can check later this evening but I have an appointment now.
>> 
>> > 
>> >> 
>> >> Please note only the pkgsrc version of Xen crashes. I can boot Xen with no problems using Xen packaged by Fedora, AlmaLinux, etc. on this box.
>> > 
>> > Is it the same Xen version ?
>> 
>> More or less - I know Xen 4.18.4 worked, now Fedora is at Xen 4.19.
> 
> strange; maybe they had a patch.
> Note that I just updated xen in pkgsrc to 4.18.5
> 

Actually, I do remember that Xen 4.19.1 from Fedora did not work on my box but a patch that was added in 4.19.2 fixed it. I see the patch I needed on the Xen 4.19 branch was not added in Xen 4.18.4 but it is added in Xen 4.18.5, so maybe it will be fixed in Xen 4.18.5. I will try it when I can download Xen 4.18.5.

Thanks.