Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

Pull ARM fix from Russell King: "One further ARM fix for 6.1 from Wang Kefeng, fixing up the handling for kfence faults" * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 9278/1: kfence: only handle translation faults
marcelteraflow · Dec 10, 2022 · 296a7b7 · 296a7b7
2 parents 3ecc379 + 73a0b6e
commit 296a7b7
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Showing 2 changed files with 22 additions and 5 deletions.
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
@@ -105,6 +105,19 @@ static inline bool is_write_fault(unsigned int fsr)
 	return (fsr & FSR_WRITE) && !(fsr & FSR_CM);
 }
 
+static inline bool is_translation_fault(unsigned int fsr)
+{
+	int fs = fsr_fs(fsr);
+#ifdef CONFIG_ARM_LPAE
+	if ((fs & FS_MMU_NOLL_MASK) == FS_TRANS_NOLL)
+		return true;
+#else
+	if (fs == FS_L1_TRANS || fs == FS_L2_TRANS)
+		return true;
+#endif
+	return false;
+}
+
 static void die_kernel_fault(const char *msg, struct mm_struct *mm,
 			     unsigned long addr, unsigned int fsr,
 			     struct pt_regs *regs)
@@ -140,7 +153,8 @@ __do_kernel_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr,
 	if (addr < PAGE_SIZE) {
 		msg = "NULL pointer dereference";
 	} else {
-		if (kfence_handle_page_fault(addr, is_write_fault(fsr), regs))
+		if (is_translation_fault(fsr) &&
+		    kfence_handle_page_fault(addr, is_write_fault(fsr), regs))
 			return;
 
 		msg = "paging request";
@@ -208,7 +222,7 @@ static inline bool is_permission_fault(unsigned int fsr)
 {
 	int fs = fsr_fs(fsr);
 #ifdef CONFIG_ARM_LPAE
-	if ((fs & FS_PERM_NOLL_MASK) == FS_PERM_NOLL)
+	if ((fs & FS_MMU_NOLL_MASK) == FS_PERM_NOLL)
 		return true;
 #else
 	if (fs == FS_L1_PERM || fs == FS_L2_PERM)

diff --git a/arch/arm/mm/fault.h b/arch/arm/mm/fault.h
@@ -14,17 +14,20 @@
 
 #ifdef CONFIG_ARM_LPAE
 #define FSR_FS_AEA		17
+#define FS_TRANS_NOLL		0x4
 #define FS_PERM_NOLL		0xC
-#define FS_PERM_NOLL_MASK	0x3C
+#define FS_MMU_NOLL_MASK	0x3C
 
 static inline int fsr_fs(unsigned int fsr)
 {
 	return fsr & FSR_FS5_0;
 }
 #else
 #define FSR_FS_AEA		22
-#define FS_L1_PERM             0xD
-#define FS_L2_PERM             0xF
+#define FS_L1_TRANS		0x5
+#define FS_L2_TRANS		0x7
+#define FS_L1_PERM		0xD
+#define FS_L2_PERM		0xF
 
 static inline int fsr_fs(unsigned int fsr)
 {