This is a note to let you know that I've just added the patch titled
parisc: Fix lpa and lpa_user defines
to the 5.16-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
parisc-fix-lpa-and-lpa_user-defines.patch
and it can be found in the queue-5.16 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From db19c6f1a2a353cc8dec35b4789733a3cf6e2838 Mon Sep 17 00:00:00 2001
From: John David Anglin <dave.anglin@xxxxxxxx>
Date: Wed, 22 Dec 2021 16:01:31 +0000
Subject: parisc: Fix lpa and lpa_user defines
From: John David Anglin <dave.anglin@xxxxxxxx>
commit db19c6f1a2a353cc8dec35b4789733a3cf6e2838 upstream.
While working on the rewrite to the light-weight syscall and futex code, I
experimented with using a hash index based on the user physical address of
atomic variable. This exposed two problems with the lpa and lpa_user defines.
Because of the copy instruction, the pa argument needs to be an early clobber
argument. This prevents gcc from allocating the va and pa arguments to the same
register.
Secondly, the lpa instruction can cause a page fault so we need to catch
exceptions.
Signed-off-by: John David Anglin <dave.anglin@xxxxxxxx>
Fixes: 116d753308cf ("parisc: Use lpa instruction to load physical addresses in driver code")
Signed-off-by: Helge Deller <deller@xxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v5.2+
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/parisc/include/asm/special_insns.h | 44 +++++++++++++++++---------------
1 file changed, 24 insertions(+), 20 deletions(-)
--- a/arch/parisc/include/asm/special_insns.h
+++ b/arch/parisc/include/asm/special_insns.h
@@ -2,28 +2,32 @@
#ifndef __PARISC_SPECIAL_INSNS_H
#define __PARISC_SPECIAL_INSNS_H
-#define lpa(va) ({ \
- unsigned long pa; \
- __asm__ __volatile__( \
- "copy %%r0,%0\n\t" \
- "lpa %%r0(%1),%0" \
- : "=r" (pa) \
- : "r" (va) \
- : "memory" \
- ); \
- pa; \
+#define lpa(va) ({ \
+ unsigned long pa; \
+ __asm__ __volatile__( \
+ "copy %%r0,%0\n" \
+ "8:\tlpa %%r0(%1),%0\n" \
+ "9:\n" \
+ ASM_EXCEPTIONTABLE_ENTRY(8b, 9b) \
+ : "=&r" (pa) \
+ : "r" (va) \
+ : "memory" \
+ ); \
+ pa; \
})
-#define lpa_user(va) ({ \
- unsigned long pa; \
- __asm__ __volatile__( \
- "copy %%r0,%0\n\t" \
- "lpa %%r0(%%sr3,%1),%0" \
- : "=r" (pa) \
- : "r" (va) \
- : "memory" \
- ); \
- pa; \
+#define lpa_user(va) ({ \
+ unsigned long pa; \
+ __asm__ __volatile__( \
+ "copy %%r0,%0\n" \
+ "8:\tlpa %%r0(%%sr3,%1),%0\n" \
+ "9:\n" \
+ ASM_EXCEPTIONTABLE_ENTRY(8b, 9b) \
+ : "=&r" (pa) \
+ : "r" (va) \
+ : "memory" \
+ ); \
+ pa; \
})
#define mfctl(reg) ({ \
Patches currently in stable-queue which might be from dave.anglin@xxxxxxxx are
queue-5.16/parisc-avoid-calling-faulthandler_disabled-twice.patch
queue-5.16/parisc-fix-lpa-and-lpa_user-defines.patch
