This is a note to let you know that I've just added the patch titled
RISC-V: selftests: cbo: Ensure asm operands match constraints
to the 6.7-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:
risc-v-selftests-cbo-ensure-asm-operands-match-constraints.patch
and it can be found in the queue-6.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 0de65288d75ff96c30e216557d979fb9342c4323 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ajones@xxxxxxxxxxxxxxxx>
Date: Wed, 17 Jan 2024 14:09:34 +0100
Subject: RISC-V: selftests: cbo: Ensure asm operands match constraints
From: Andrew Jones <ajones@xxxxxxxxxxxxxxxx>
commit 0de65288d75ff96c30e216557d979fb9342c4323 upstream.
The 'i' constraint expects a constant operand, which fn and its
constant derivative MK_CBO(fn) are, but passing fn through a function
as a parameter and using a local variable for MK_CBO(fn) allow the
compiler to lose sight of that when no optimization is done. Use
a macro instead of a function and skip the local variable to ensure
the compiler uses constants, matching the asm constraints.
Reported-by: Yunhui Cui <cuiyunhui@xxxxxxxxxxxxx>
Closes: https://lore.kernel.org/all/20240117082514.42967-1-cuiyunhui@xxxxxxxxxxxxx
Fixes: a29e2a48afe3 ("RISC-V: selftests: Add CBO tests")
Signed-off-by: Andrew Jones <ajones@xxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240117130933.57514-2-ajones@xxxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/riscv/hwprobe/cbo.c | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)
--- a/tools/testing/selftests/riscv/hwprobe/cbo.c
+++ b/tools/testing/selftests/riscv/hwprobe/cbo.c
@@ -36,16 +36,14 @@ static void sigill_handler(int sig, sigi
regs[0] += 4;
}
-static void cbo_insn(char *base, int fn)
-{
- uint32_t insn = MK_CBO(fn);
-
- asm volatile(
- "mv a0, %0\n"
- "li a1, %1\n"
- ".4byte %2\n"
- : : "r" (base), "i" (fn), "i" (insn) : "a0", "a1", "memory");
-}
+#define cbo_insn(base, fn) \
+({ \
+ asm volatile( \
+ "mv a0, %0\n" \
+ "li a1, %1\n" \
+ ".4byte %2\n" \
+ : : "r" (base), "i" (fn), "i" (MK_CBO(fn)) : "a0", "a1", "memory"); \
+})
static void cbo_inval(char *base) { cbo_insn(base, 0); }
static void cbo_clean(char *base) { cbo_insn(base, 1); }
Patches currently in stable-queue which might be from ajones@xxxxxxxxxxxxxxxx are
queue-6.7/risc-v-selftests-cbo-ensure-asm-operands-match-constraints.patch
