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: Kai Huang <kai.huang@intel.com>
Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Link: https://patch.msgid.link/20260218210820.2828896-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 9c26038f6b77ec84287046f408a6b8d8a314f3f2..7b1102d26f9cd5e14e12238a76e79e0d7eddd7d8 100644 (file)
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -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;