Re: preparations for 4.17.4

[Jan Beulich <jbeulich@xxxxxxxx>]

On 27.03.2024 13:33, Andrew Cooper wrote:
> 1) livepatching of .rodata:
> 
> 989556c6f8ca - xen/virtual-region: Rename the start/end fields
> ef969144a425 - xen/virtual-region: Include rodata pointers
> b083b1c393dc - x86/livepatch: Relax permissions on rodata too
> 
> And technically "x86/mm: fix detection of last L1 entry in
> modify_xen_mappings_lite()" too but you've already backported this one.
> 
> Patching .rodata worked before Xen 4.17, and was broken (left as a TODO)
> when I adjusted Xen to stop using CR0.WP=0 for patching.
> 
> 
> 2) Policy fixes:
> 
> e2d8a6522516 - x86/cpu-policy: Fix visibility of HTT/CMP_LEGACY in max
> policies
> 
> This is a real bugfix for a real regression we found updating from Xen
> 4.13 -> 4.17.  It has a dependency on
> 
> 5420aa165dfa - x86/cpu-policy: Hide x2APIC from PV guests
> 
> which I know you had more concern with.  FWIW, I'm certain its a good
> fix, and should be backported.
> 
> 
> 3) Test fixes:
> 
> 0263dc9069dd - tests/resource: Fix HVM guest in !SHADOW builds
> 
> It's minor, but does make a difference for those of us who run these
> tests regularly.
> 
> 
> 4) Watchdog fixes:
> 
> 9e18f339830c - x86/boot: Improve the boot watchdog determination of
> stuck cpus
> 131892e0dcc1 - x86/boot: Support the watchdog on newer AMD systems
> 
> You took "x86/boot: Fix setup_apic_nmi_watchdog() to fail more cleanly"
> and the first of the two patches is in the same category IMO.  The
> second I also feel ok to take for the in-support releases, particularly
> as all it is doing is dropping a family list.

I've pushed all of the above.

> 5) Ucode scan stability  (For 4.18 only)
> 
> Xen 4.18 had "x86/ucode: Refresh raw CPU policy after microcode load" in
> it's .0 release, so should also gain:
> 
> cf7fe8b72dea - x86/ucode: Fix stability of the raw CPU Policy rescan

This already is in 4.18.1, ...

> I've only noticed because I've got them both backported to 4.17 in
> XenServer, but I don't think upstream wants to take that route.

... while, as you suggest, not (and not intended to be) in 4.17.

Jan