linux-kernel - [PATCH 3/8] KVM: x86/mmu: Bury 32-bit PSE paging helpers in paging

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: <20220613225723.2734132-4-seanjc@google.com>
Date:   Mon, 13 Jun 2022 22:57:18 +0000
From:   Sean Christopherson <seanjc@...gle.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <seanjc@...gle.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH 3/8] KVM: x86/mmu: Bury 32-bit PSE paging helpers in paging_tmpl.h

Move a handful of one-off macros and helpers for 32-bit PSE paging into
paging_tmpl.h and hide them behind "PTTYPE == 32".  Under no circumstance
should anything but 32-bit shadow paging care about PSE paging.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/mmu.h             |  5 -----
 arch/x86/kvm/mmu/mmu.c         | 12 ------------
 arch/x86/kvm/mmu/paging_tmpl.h | 19 ++++++++++++++++++-
 3 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index f8192864b496..d1021e34ac15 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -34,11 +34,6 @@
 #define PT_DIR_PAT_SHIFT 12
 #define PT_DIR_PAT_MASK (1ULL << PT_DIR_PAT_SHIFT)
 
-#define PT32_DIR_PSE36_SIZE 4
-#define PT32_DIR_PSE36_SHIFT 13
-#define PT32_DIR_PSE36_MASK \
-	(((1ULL << PT32_DIR_PSE36_SIZE) - 1) << PT32_DIR_PSE36_SHIFT)
-
 #define PT64_ROOT_5LEVEL 5
 #define PT64_ROOT_4LEVEL 4
 #define PT32_ROOT_LEVEL 2
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 17252f39bd7c..f1961fe3fe67 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -321,18 +321,6 @@ static bool check_mmio_spte(struct kvm_vcpu *vcpu, u64 spte)
 	return likely(kvm_gen == spte_gen);
 }
 
-static int is_cpuid_PSE36(void)
-{
-	return 1;
-}
-
-static gfn_t pse36_gfn_delta(u32 gpte)
-{
-	int shift = 32 - PT32_DIR_PSE36_SHIFT - PAGE_SHIFT;
-
-	return (gpte & PT32_DIR_PSE36_MASK) << shift;
-}
-
 #ifdef CONFIG_X86_64
 static void __set_spte(u64 *sptep, u64 spte)
 {
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index f595c4b8657f..ef02e6bb0bcb 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -50,6 +50,12 @@
 	#define PT_GUEST_DIRTY_SHIFT PT_DIRTY_SHIFT
 	#define PT_GUEST_ACCESSED_SHIFT PT_ACCESSED_SHIFT
 	#define PT_HAVE_ACCESSED_DIRTY(mmu) true
+
+	#define is_cpuid_PSE36() true
+	#define PT32_DIR_PSE36_SIZE 4
+	#define PT32_DIR_PSE36_SHIFT 13
+	#define PT32_DIR_PSE36_MASK \
+		(((1ULL << PT32_DIR_PSE36_SIZE) - 1) << PT32_DIR_PSE36_SHIFT)
 #elif PTTYPE == PTTYPE_EPT
 	#define pt_element_t u64
 	#define guest_walker guest_walkerEPT
@@ -92,6 +98,15 @@ struct guest_walker {
 	struct x86_exception fault;
 };
 
+#if PTTYPE == 32
+static inline gfn_t pse36_gfn_delta(u32 gpte)
+{
+	int shift = 32 - PT32_DIR_PSE36_SHIFT - PAGE_SHIFT;
+
+	return (gpte & PT32_DIR_PSE36_MASK) << shift;
+}
+#endif
+
 static gfn_t gpte_to_gfn_lvl(pt_element_t gpte, int lvl)
 {
 	return (gpte & PT_LVL_ADDR_MASK(lvl)) >> PAGE_SHIFT;
@@ -416,8 +431,10 @@ static int FNAME(walk_addr_generic)(struct guest_walker *walker,
 	gfn = gpte_to_gfn_lvl(pte, walker->level);
 	gfn += (addr & PT_LVL_OFFSET_MASK(walker->level)) >> PAGE_SHIFT;
 
-	if (PTTYPE == 32 && walker->level > PG_LEVEL_4K && is_cpuid_PSE36())
+#if PTTYPE == 32
+	if (walker->level > PG_LEVEL_4K && is_cpuid_PSE36())
 		gfn += pse36_gfn_delta(pte);
+#endif
 
 	real_gpa = kvm_translate_gpa(vcpu, mmu, gfn_to_gpa(gfn), access, &walker->fault);
 	if (real_gpa == UNMAPPED_GVA)
-- 
2.36.1.476.g0c4daa206d-goog