linux-kernel - [RFC PATCH 06/16] KVM: arm64: Pass kvm_page_fault pointer to transparent_hugepage

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250821210042.3451147-7-seanjc@google.com>
Date: Thu, 21 Aug 2025 14:00:32 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Marc Zyngier <maz@...nel.org>, Oliver Upton <oliver.upton@...ux.dev>
Cc: linux-arm-kernel@...ts.infradead.org, kvmarm@...ts.linux.dev, 
	linux-kernel@...r.kernel.org, Sean Christopherson <seanjc@...gle.com>, 
	James Houghton <jthoughton@...gle.com>
Subject: [RFC PATCH 06/16] KVM: arm64: Pass kvm_page_fault pointer to transparent_hugepage_adjust()

Use the local kvm_page_fault structure to adjust for transparent hugepages
when resolving guest aborts, to reduce the number of parameters from 5=>2,
and to eliminate the less-than-pleasant pointer dereferences.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/arm64/kvm/mmu.c | 20 ++++++--------------
 1 file changed, 6 insertions(+), 14 deletions(-)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index ca98778989b2..047aba00388c 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1361,19 +1361,15 @@ static bool fault_supports_stage2_huge_mapping(struct kvm_memory_slot *memslot,
  * Returns the size of the mapping.
  */
 static long
-transparent_hugepage_adjust(struct kvm *kvm, struct kvm_memory_slot *memslot,
-			    unsigned long hva, kvm_pfn_t *pfnp,
-			    phys_addr_t *ipap)
+transparent_hugepage_adjust(struct kvm *kvm, struct kvm_page_fault *fault)
 {
-	kvm_pfn_t pfn = *pfnp;
-
 	/*
 	 * Make sure the adjustment is done only for THP pages. Also make
 	 * sure that the HVA and IPA are sufficiently aligned and that the
 	 * block map is contained within the memslot.
 	 */
-	if (fault_supports_stage2_huge_mapping(memslot, hva, PMD_SIZE)) {
-		int sz = get_user_mapping_size(kvm, hva);
+	if (fault_supports_stage2_huge_mapping(fault->slot, fault->hva, PMD_SIZE)) {
+		int sz = get_user_mapping_size(kvm, fault->hva);
 
 		if (sz < 0)
 			return sz;
@@ -1381,10 +1377,8 @@ transparent_hugepage_adjust(struct kvm *kvm, struct kvm_memory_slot *memslot,
 		if (sz < PMD_SIZE)
 			return PAGE_SIZE;
 
-		*ipap &= PMD_MASK;
-		pfn &= ~(PTRS_PER_PMD - 1);
-		*pfnp = pfn;
-
+		fault->ipa &= PMD_MASK;
+		fault->pfn &= ~(PTRS_PER_PMD - 1);
 		return PMD_SIZE;
 	}
 
@@ -1724,9 +1718,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault)
 		if (fault->is_perm && fault_granule > PAGE_SIZE)
 			vma_pagesize = fault_granule;
 		else
-			vma_pagesize = transparent_hugepage_adjust(kvm, fault->slot,
-								   fault->hva, &fault->pfn,
-								   &fault->fault_ipa);
+			vma_pagesize = transparent_hugepage_adjust(kvm, fault);
 
 		if (vma_pagesize < 0) {
 			ret = vma_pagesize;
-- 
2.51.0.261.g7ce5a0a67e-goog