linux-kernel - [PATCH 1/2] riscv: mm: Apply svinval in update_mmu

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: <20250827131444.23893-2-luxu.kernel@bytedance.com>
Date: Wed, 27 Aug 2025 21:14:43 +0800
From: Xu Lu <luxu.kernel@...edance.com>
To: paul.walmsley@...ive.com,
	palmer@...belt.com,
	aou@...s.berkeley.edu,
	alex@...ti.fr
Cc: linux-riscv@...ts.infradead.org,
	linux-kernel@...r.kernel.org,
	Xu Lu <luxu.kernel@...edance.com>
Subject: [PATCH 1/2] riscv: mm: Apply svinval in update_mmu_cache()

Only flush tlb of the specified mm, and apply svinval if available.

Signed-off-by: Xu Lu <luxu.kernel@...edance.com>
---
 arch/riscv/include/asm/pgtable.h  | 16 +++++++++++++++-
 arch/riscv/include/asm/tlbflush.h | 23 +++++++++++++++++++++++
 arch/riscv/mm/tlbflush.c          | 23 -----------------------
 3 files changed, 38 insertions(+), 24 deletions(-)

diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 91697fbf1f901..165cd02d51629 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -495,9 +495,15 @@ static inline void update_mmu_cache_range(struct vm_fault *vmf,
 		struct vm_area_struct *vma, unsigned long address,
 		pte_t *ptep, unsigned int nr)
 {
+	int i;
+	unsigned long asid = get_mm_asid(vma->vm_mm);
+
 	asm goto(ALTERNATIVE("nop", "j %l[svvptc]", 0, RISCV_ISA_EXT_SVVPTC, 1)
 		 : : : : svvptc);
 
+	asm goto(ALTERNATIVE("nop", "j %l[svinval]", 0, RISCV_ISA_EXT_SVINVAL, 1)
+		 : : : : svinval);
+
 	/*
 	 * The kernel assumes that TLBs don't cache invalid entries, but
 	 * in RISC-V, SFENCE.VMA specifies an ordering constraint, not a
@@ -506,7 +512,15 @@ static inline void update_mmu_cache_range(struct vm_fault *vmf,
 	 * the extra traps reduce performance.  So, eagerly SFENCE.VMA.
 	 */
 	while (nr--)
-		local_flush_tlb_page(address + nr * PAGE_SIZE);
+		local_flush_tlb_page_asid(address + nr * PAGE_SIZE, asid);
+	return;
+
+svinval:
+	local_sfence_w_inval();
+	for (i = 0; i < nr; i++)
+		local_sinval_vma(address + nr * PAGE_SIZE, asid);
+	local_sfence_inval_ir();
+	return;
 
 svvptc:;
 	/*
diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h
index eed0abc405143..9636d07fe9eed 100644
--- a/arch/riscv/include/asm/tlbflush.h
+++ b/arch/riscv/include/asm/tlbflush.h
@@ -15,6 +15,29 @@
 #define FLUSH_TLB_NO_ASID       ((unsigned long)-1)
 
 #ifdef CONFIG_MMU
+static inline unsigned long get_mm_asid(struct mm_struct *mm)
+{
+	return mm ? cntx2asid(atomic_long_read(&mm->context.id)) : FLUSH_TLB_NO_ASID;
+}
+
+static inline void local_sfence_inval_ir(void)
+{
+	asm volatile(SFENCE_INVAL_IR() ::: "memory");
+}
+
+static inline void local_sfence_w_inval(void)
+{
+	asm volatile(SFENCE_W_INVAL() ::: "memory");
+}
+
+static inline void local_sinval_vma(unsigned long vma, unsigned long asid)
+{
+	if (asid != FLUSH_TLB_NO_ASID)
+		asm volatile(SINVAL_VMA(%0, %1) : : "r" (vma), "r" (asid) : "memory");
+	else
+		asm volatile(SINVAL_VMA(%0, zero) : : "r" (vma) : "memory");
+}
+
 static inline void local_flush_tlb_all(void)
 {
 	__asm__ __volatile__ ("sfence.vma" : : : "memory");
diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c
index 8404530ec00f9..962db300a1665 100644
--- a/arch/riscv/mm/tlbflush.c
+++ b/arch/riscv/mm/tlbflush.c
@@ -11,24 +11,6 @@
 
 #define has_svinval()	riscv_has_extension_unlikely(RISCV_ISA_EXT_SVINVAL)
 
-static inline void local_sfence_inval_ir(void)
-{
-	asm volatile(SFENCE_INVAL_IR() ::: "memory");
-}
-
-static inline void local_sfence_w_inval(void)
-{
-	asm volatile(SFENCE_W_INVAL() ::: "memory");
-}
-
-static inline void local_sinval_vma(unsigned long vma, unsigned long asid)
-{
-	if (asid != FLUSH_TLB_NO_ASID)
-		asm volatile(SINVAL_VMA(%0, %1) : : "r" (vma), "r" (asid) : "memory");
-	else
-		asm volatile(SINVAL_VMA(%0, zero) : : "r" (vma) : "memory");
-}
-
 /*
  * Flush entire TLB if number of entries to be flushed is greater
  * than the threshold below.
@@ -110,11 +92,6 @@ static void __ipi_flush_tlb_range_asid(void *info)
 	local_flush_tlb_range_asid(d->start, d->size, d->stride, d->asid);
 }
 
-static inline unsigned long get_mm_asid(struct mm_struct *mm)
-{
-	return mm ? cntx2asid(atomic_long_read(&mm->context.id)) : FLUSH_TLB_NO_ASID;
-}
-
 static void __flush_tlb_range(struct mm_struct *mm,
 			      const struct cpumask *cmask,
 			      unsigned long start, unsigned long size,
-- 
2.20.1