Re: [PATCH] MIPS: Fix IRQ tracing when call handle_fpe()

From: Sergei Shtylyov
Date: Mon May 25 2020 - 04:34:51 EST


Hello!

On 25.05.2020 6:31, YuanJunQing wrote:

Register "a1" is unsaved in this function,
when CONFIG_TRACE_IRQFLAGS is enabled,
the TRACE_IRQS_OFF macro will call trace_hardirqs_off(),
and this may change register "a1".
The variment of register "a1" may send SIGFPE signal

Variment?

to task when call do_fpe(),and this may kill the task.

Need space after comma.

Signed-off-by: YuanJunQing <yuanjunqing66@xxxxxxx>
---
arch/mips/kernel/genex.S | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S
index 8236fb291e3f..956a76429773 100644
--- a/arch/mips/kernel/genex.S
+++ b/arch/mips/kernel/genex.S
@@ -480,16 +480,18 @@ NESTED(nmi_handler, PT_SIZE, sp)
/* gas fails to assemble cfc1 for some archs (octeon).*/ \
.set mips1
SET_HARDFLOAT
- cfc1 a1, fcr31
+ cfc1 s0, fcr31
.set pop
CLI
TRACE_IRQS_OFF
+ move a1,s0

Need space after comma.

.endm
.macro __build_clear_msa_fpe
- _cfcmsa a1, MSA_CSR
+ _cfcmsa s0, MSA_CSR
CLI
TRACE_IRQS_OFF
+ move a1,s0

Ditto.

[...]

MBR, Sergei