We know the answer, so don't ask the user.
Signed-off-by: Changbin Du <[email protected]>
---
arch/x86/mm/extable.c | 5 ++++-
arch/x86/mm/mm_internal.h | 11 +++++++++++
2 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
index 4d75bc656f97..5196e586756f 100644
--- a/arch/x86/mm/extable.c
+++ b/arch/x86/mm/extable.c
@@ -8,6 +8,8 @@
#include <asm/traps.h>
#include <asm/kdebug.h>
+#include "mm_internal.h"
+
typedef bool (*ex_handler_t)(const struct exception_table_entry *,
struct pt_regs *, int, unsigned long,
unsigned long);
@@ -123,7 +125,8 @@ __visible bool ex_handler_uaccess(const struct
exception_table_entry *fixup,
unsigned long error_code,
unsigned long fault_addr)
{
- WARN_ONCE(trapnr == X86_TRAP_GP, "General protection fault in user
access. Non-canonical address?");
+ WARN_ONCE(trapnr == X86_TRAP_GP, "General protection fault at %s
address in user access.",
+ is_canonical_addr(fault_addr) ? "canonical" :
"non-canonical");
regs->ip = ex_fixup_addr(fixup);
return true;
}
diff --git a/arch/x86/mm/mm_internal.h b/arch/x86/mm/mm_internal.h
index eeae142062ed..4c8a0fdd1c64 100644
--- a/arch/x86/mm/mm_internal.h
+++ b/arch/x86/mm/mm_internal.h
@@ -2,6 +2,17 @@
#ifndef __X86_MM_INTERNAL_H
#define __X86_MM_INTERNAL_H
+static inline bool is_canonical_addr(u64 addr)
+{
+#ifdef CONFIG_X86_64
+ int shift = 64 - boot_cpu_data.x86_phys_bits;
+
+ return ((int64_t)addr << shift >> shift) == addr;
+#else
+ return true;
+#endif
+}
+
void *alloc_low_pages(unsigned int num);
static inline void *alloc_low_page(void)
{
--
2.20.1
