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Subject[PATCH] arm64/traps: Avoid unnecessary kernel/user pointer conversion
Date
Annotating a pointer from kernel to __user and then back again might
confuse sparse. In call_undef_hook() it can be avoided by not using the
intermediate user pointer variable.

Note: This patch adds no functional changes to code.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
---
arch/arm64/kernel/traps.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index b03e383d944a..357d10a8bbf5 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -404,7 +404,8 @@ static int call_undef_hook(struct pt_regs *regs)

if (!user_mode(regs)) {
__le32 instr_le;
- if (get_kernel_nofault(instr_le, (__force __le32 *)pc))
+ if (get_kernel_nofault(instr_le,
+ (__le32 *)instruction_pointer(regs)))
goto exit;
instr = le32_to_cpu(instr_le);
} else if (compat_thumb_mode(regs)) {
--
2.17.1
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