Commit 73a0b6ee authored by Wang Kefeng's avatar Wang Kefeng Committed by Russell King (Oracle)
Browse files

ARM: 9278/1: kfence: only handle translation faults 



This is a similar fixup like arm64 does, only handle translation faults
in case of unexpected kfence report when alignment faults on ARM, see
more from commit 0bb1fbff ("arm64: mm: kfence: only handle translation
faults").

Fixes: 75969686 ("ARM: 9166/1: Support KFENCE for ARM")
Signed-off-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: default avatarRussell King (Oracle) <rmk+kernel@armlinux.org.uk>
parent 340a9828

arch/arm/mm/fault.c

+16 −2
Original line number Diff line number Diff line
@@ -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)

arch/arm/mm/fault.h

+6 −3
Original line number Diff line number Diff line
@@ -14,8 +14,9 @@ 


#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)

{
@@ -23,6 +24,8 @@ static inline int fsr_fs(unsigned int fsr) 
}

#else

#define FSR_FS_AEA		22

#define FS_L1_TRANS		0x5

#define FS_L2_TRANS		0x7

#define FS_L1_PERM		0xD

#define FS_L2_PERM		0xF