Commit ecb80629 authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: x86/mmu: Don't zero-allocate page table used for splitting a hugepage 



When splitting hugepages in the TDP MMU, don't zero the new page table on
allocation since tdp_mmu_split_huge_page() is guaranteed to write every
entry and thus every byte.

Unless someone peeks at the memory between allocating the page table and
writing the child SPTEs, no functional change intended.

Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Kai Huang <kai.huang@intel.com>
Reviewed-by: default avatarKai Huang <kai.huang@intel.com>
Reviewed-by: default avatarRick Edgecombe <rick.p.edgecombe@intel.com>
Link: https://patch.msgid.link/20260218210820.2828896-1-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 1450ab08

arch/x86/kvm/mmu/tdp_mmu.c

+1 −1
Original line number Diff line number Diff line
@@ -1507,7 +1507,7 @@ static struct kvm_mmu_page *tdp_mmu_alloc_sp_for_split(void) 
	if (!sp)

		return NULL;



	sp->spt = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT);

	sp->spt = (void *)__get_free_page(GFP_KERNEL_ACCOUNT);

	if (!sp->spt) {

		kmem_cache_free(mmu_page_header_cache, sp);

		return NULL;