[PATCH AUTOSEL 6.4 07/12] arm64: cpufeature: detect FEAT_HCX

[Sasha Levin]

On Mon, Jul 03, 2023 at 12:51:57PM +0100, Mark Brown wrote:
>On Sun, Jul 02, 2023 at 03:50:52PM -0400, Sasha Levin wrote:
>> From: Kristina Martsenko <kristina.martsenko at arm.com>
>>
>> [ Upstream commit b0c756fe996ac930033882ca56410639e5cad1ec ]
>>
>> Detect if the system has the new HCRX_EL2 register added in ARMv8.7/9.2,
>> so that subsequent patches can check for its presence.
>>
>> KVM currently relies on the register being present on all CPUs (or
>> none), so the kernel will panic if that is not the case. Fortunately no
>> such systems currently exist, but this can be revisited if they appear.
>> Note that the kernel will not panic if CONFIG_KVM is disabled.
>
>This is a new feature, it's not clear why we'd backport it (especially
>since it's a new feature which is a dependency for other features rather
>than something that people can use outside of the kernel)?

The second paragraph (above) suggested it should be.

-- 
Thanks,
Sasha