Re: [PATCH v3][4.15] x86: mirror compat argument translation area for 32-bit PV

[Jan Beulich <jbeulich@xxxxxxxx>]

On 25.02.2021 10:30, Jan Beulich wrote:
> Now that we guard the entire Xen VA space against speculative abuse
> through hypervisor accesses to guest memory, the argument translation
> area's VA also needs to live outside this range, at least for 32-bit PV
> guests. To avoid extra is_hvm_*() conditionals, use the alternative VA
> uniformly.
> 
> While this could be conditionalized upon CONFIG_PV32 &&
> CONFIG_SPECULATIVE_HARDEN_GUEST_ACCESS, omitting such extra conditionals
> keeps the code more legible imo.
> 
> Fixes: 4dc181599142 ("x86/PV: harden guest memory accesses against 
> speculative abuse")
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
> Acked-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>

Roger - I would have dropped an R-b, but I've assumed keeping an A-b
would be fine. Please let me know if this was wrong.

Jan