Re: [xen-unstable-smoke test] 171511: regressions - FAIL

[Jan Beulich <jbeulich@xxxxxxxx>]

On 06.07.2022 08:56, Demi Marie Obenour wrote:
>>> commit 8d410ac2c178e1dd1001cadddbe9ca75a9738c95
>>> Author: Demi Marie Obenour <demi@xxxxxxxxxxxxxxxxxxxxxx>
>>> Date:   Tue Jul 5 13:10:46 2022 +0200
>>>
>>>     EFI: preserve the System Resource Table for dom0
>>>     
>>>     The EFI System Resource Table (ESRT) is necessary for fwupd to identify
>>>     firmware updates to install.  According to the UEFI specification §23.4,
>>>     the ESRT shall be stored in memory of type EfiBootServicesData.  
>>> However,
>>>     memory of type EfiBootServicesData is considered general-purpose memory
>>>     by Xen, so the ESRT needs to be moved somewhere where Xen will not
>>>     overwrite it.  Copy the ESRT to memory of type EfiRuntimeServicesData,
>>>     which Xen will not reuse.  dom0 can use the ESRT if (and only if) it is
>>>     in memory of type EfiRuntimeServicesData.
>>>     
>>>     Earlier versions of this patch reserved the memory in which the ESRT was
>>>     located.  This created awkward alignment problems, and required either
>>>     splitting the E820 table or wasting memory.  It also would have required
>>>     a new platform op for dom0 to use to indicate if the ESRT is reserved.
>>>     By copying the ESRT into EfiRuntimeServicesData memory, the E820 table
>>>     does not need to be modified, and dom0 can just check the type of the
>>>     memory region containing the ESRT.  The copy is only done if the ESRT is
>>>     not already in EfiRuntimeServicesData memory, avoiding memory leaks on
>>>     repeated kexec.
>>>     
>>>     See https://lore.kernel.org/xen-devel/20200818184018.GN1679@mail-itl/T/
>>>     for details.
>>>     
>>>     Signed-off-by: Demi Marie Obenour <demi@xxxxxxxxxxxxxxxxxxxxxx>
>>>     Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
>>
>> ... this is the most likely candidate, considering in the log all we
>> see is:
>>
>> Xen 4.17-unstable (c/s Mon Jun 27 15:15:39 2022 +0200 git:61ff273322-dirty) 
>> EFI loader
>> Jul  5 23:09:15.692859 Using configuration file 'xen.cfg'
>> Jul  5 23:09:15.704878 vmlinuz: 0x00000083fb1ac000-0x00000083fc880a00
>> Jul  5 23:09:15.704931 initrd.gz: 0x00000083f94b7000-0x00000083fb1ab6e8
>> Jul  5 23:09:15.836836 xenpolicy: 0x00000083f94b4000-0x00000083f94b6a5f
>> Jul  5 23:09:15.980866 Using bootargs from Xen configuration file.
> 
> This would not surprise me at all.  I was hoping that Jan would be able
> to test this before he merged it, especially the ARM-specific stuff.

Jan (i.e. me)? I've never done any testing on Arm; all I do is build-test
things there. Also if you suspected there might be issues, I think you
should have arranged for someone to test this, i.e. at the very least
indicate so in a post-commit-message remark targeted at the eventual
committer.

Jan