KVM: arm64: Don't WARN on pKVM stage-2 map failures

pkvm_pgtable_stage2_map() wraps the __pkvm_host_share_guest() and
__pkvm_host_donate_guest() return in WARN_ON(), but those hypercalls
fail for reasons that are not EL1 invariant violations: -EINVAL for a
pfn that is not memblock RAM (check_range_allowed_memory() rejects a
device page mapped into a non-protected guest) and -ENOMEM under
memcache pressure. Both are reachable from a guest fault, so the WARN
splats on host input.

Return the error without warning. The unshare and write-protect WARNs
stay, since a failure there does signal a broken EL1 invariant.

Fixes: 3669ddd8fa8b5 ("KVM: arm64: Add a range to pkvm_mappings")
Signed-off-by: Fuad Tabba <fuad.tabba@linux.dev>
Reviewed-by: Bradley Morgan <include@grrlz.net>
Tested-by: Bradley Morgan <include@grrlz.net> # On pixel 7, Android 17 CP2A.260705.006
Test: Bradley Morgan <include@grrlz.net> # On QEMU arm64 host
Link: https://patch.msgid.link/20260717130317.1953574-6-fuad.tabba@linux.dev
Signed-off-by: Oliver Upton <oupton@kernel.org>

0 files changed, 0 insertions, 0 deletions