Re: [PATCH v2 3/3] KVM: arm64: Don't replace a valid hyp block mapping with a table

[Vincent Donnefort <vdonnefort@google.com>]

On Fri, Nov 06, 2026 at 12:03:29PM +0000, Fuad Tabba wrote:
> Hi Xuheng,
> 
> On Thu, 05 Nov 2026 22:59:50 +0000, Xuheng Li <xuheng@cs.columbia.edu> wrote:
> [...]
> > No in-tree caller maps into an existing hyp block mapping today, so this
> > cannot be triggered in mainline.  Fail such a request with -EEXIST
> > instead, so that a future caller gets an error rather than silently
> > losing the rest of the block.
> 
> Could you mention in the message that the WARN_ON() is fatal at EL2,
> so a caller there gets a hyp panic rather than -EEXIST?
> kvm_pgtable_hyp_map() is already documented as rejecting such a
> mapping "with an error and a WARN()", which is a better reason than a
> future caller.
> 
> Also, please don't respin series so fast. Give us time to digest the
> series first :)
> 
> Cheers,
> /fuad
>

Actually, why making it fatal? All callers of kvm_pgtable_hyp_map() are checking
for the returned error.

-- 
Vincent