Re: [PATCH 0/4] KVM: arm64: Fix host access to the EL2 stacks

[Oliver Upton]

On Tue, 08 Sep 2026 12:07:09 +0100, Fuad Tabba wrote:
> The per-CPU EL2 stacks are initialised as host-owned after pKVM init.
> fix_host_ownership() walks only the linear-map alias of each memblock
> region, and the stacks, mapped in the private VA range for their guard
> pages, have none.
> 
> Patch 1 is the fix, and it needs none of the other three. Patch 4 adds
> the check that would have caught it and would catch similar instances
> in the future: once the transfer is done, walk the private VA range and
> fail init unless every valid leaf is hyp-owned, or is hyp text mapped
> without write access.
> 
> [...]

Applied to fixes, thanks!

[1/4] KVM: arm64: Transfer the hyp stack pages out of the host stage-2
      https://git.kernel.org/kvmarm/kvmarm/c/3a8c562892b9
[2/4] KVM: arm64: Match hyp text by physical address in fix_host_ownership()
      https://git.kernel.org/kvmarm/kvmarm/c/5a8b505ede13
[3/4] KVM: arm64: Move the private VA allocation cursor to __io_map_next
      https://git.kernel.org/kvmarm/kvmarm/c/224584140114
[4/4] KVM: arm64: Check every private mapping is hyp-owned at pKVM init
      https://git.kernel.org/kvmarm/kvmarm/c/cfe80c3837f9

--
Best,
Oliver