[PATCH 4.19 244/287] nios2: page fault et.al. are *not* restartable syscalls...

From: Greg Kroah-Hartman
Date: Tue Aug 23 2022 - 07:02:58 EST


From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

commit 8535c239ac674f7ead0f2652932d35c52c4123b2 upstream.

make sure that ->orig_r2 is negative for everything except
the syscalls.

Fixes: 82ed08dd1b0e ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Dinh Nguyen <dinguyen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/nios2/include/asm/entry.h | 3 ++-
arch/nios2/kernel/entry.S | 4 +---
2 files changed, 3 insertions(+), 4 deletions(-)

--- a/arch/nios2/include/asm/entry.h
+++ b/arch/nios2/include/asm/entry.h
@@ -50,7 +50,8 @@
stw r13, PT_R13(sp)
stw r14, PT_R14(sp)
stw r15, PT_R15(sp)
- stw r2, PT_ORIG_R2(sp)
+ movi r24, -1
+ stw r24, PT_ORIG_R2(sp)
stw r7, PT_ORIG_R7(sp)

stw ra, PT_RA(sp)
--- a/arch/nios2/kernel/entry.S
+++ b/arch/nios2/kernel/entry.S
@@ -185,6 +185,7 @@ ENTRY(handle_system_call)
ldw r5, PT_R5(sp)

local_restart:
+ stw r2, PT_ORIG_R2(sp)
/* Check that the requested system call is within limits */
movui r1, __NR_syscalls
bgeu r2, r1, ret_invsyscall
@@ -336,9 +337,6 @@ external_interrupt:
/* skip if no interrupt is pending */
beq r12, r0, ret_from_interrupt

- movi r24, -1
- stw r24, PT_ORIG_R2(sp)
-
/*
* Process an external hardware interrupt.
*/