From: Sean Christopherson <seanjc@google.com>
To: Sean Christopherson <seanjc@google.com>,
Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
Rick Edgecombe <rick.p.edgecombe@intel.com>,
Kai Huang <kai.huang@intel.com>
Subject: [PATCH] KVM: x86/mmu: Don't zero-allocate page table used for splitting a hugepage
Date: Wed, 18 Feb 2026 13:08:20 -0800 [thread overview]
Message-ID: <20260218210820.2828896-1-seanjc@google.com> (raw)
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>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/mmu/tdp_mmu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 9c26038f6b77..7b1102d26f9c 100644
--- 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;
base-commit: 183bb0ce8c77b0fd1fb25874112bc8751a461e49
--
2.53.0.345.g96ddfc5eaa-goog
next reply other threads:[~2026-02-18 21:08 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-18 21:08 Sean Christopherson [this message]
2026-02-18 22:30 ` [PATCH] KVM: x86/mmu: Don't zero-allocate page table used for splitting a hugepage Edgecombe, Rick P
2026-02-19 0:06 ` Huang, Kai
2026-03-05 17:07 ` Sean Christopherson
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