On 28/02/2024 3:41 pm, Sean Christopherson wrote:
Handle the "no memslot" case at the beginning of kvm_faultin_pfn(), just
after the private versus shared check, so that there's no need to
repeatedly query whether or not a slot exists. This also makes it more
obvious that, except for private vs. shared attributes, the process of
faulting in a pfn simply doesn't apply to gfns without a slot.
Opportunistically stuff @fault's metadata in kvm_handle_noslot_fault() so
that it doesn't need to be duplicated in all paths that invoke
kvm_handle_noslot_fault(), and to minimize the probability of not stuffing
the right fields.
Leave the existing handle behind, but convert it to a WARN, to guard
against __kvm_faultin_pfn() unexpectedly nullifying fault->slot.
Cc: David Matlack <dmatlack@xxxxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Reviewed-by: Kai Huang <kai.huang@xxxxxxxxx>
One nit ...
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -235,7 +235,7 @@ struct kvm_page_fault {
/* The memslot containing gfn. May be NULL. */
struct kvm_memory_slot *slot;
- /* Outputs of kvm_faultin_pfn. */
+ /* Outputs of kvm_faultin_pfn. */
unsigned long mmu_seq;
kvm_pfn_t pfn;
hva_t hva;
... how about get rid of this non-related fix?
Yeah it's annoying but do in a separate patch?
