During thread cloning the new (child) thread should have MSA disabled even
at first thread entry. So, the code to disable MSA is moved from macro
'switch_to' to assembler function 'resume' before it switches kernel stack
to 'next' (new) thread. Call of 'disable_msa' after 'resume' in 'switch_to'
macro never called a first time entry into thread.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@xxxxxxxxxx>
---
arch/mips/include/asm/switch_to.h | 1 -
arch/mips/kernel/r4k_switch.S | 6 ++++++
2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/mips/include/asm/switch_to.h b/arch/mips/include/asm/switch_to.h
index e92d6c4b5ed1..0d0f7f8f8b3a 100644
--- a/arch/mips/include/asm/switch_to.h
+++ b/arch/mips/include/asm/switch_to.h
@@ -104,7 +104,6 @@ do { \
if (test_and_clear_tsk_thread_flag(prev, TIF_USEDMSA)) \
__fpsave = FP_SAVE_VECTOR; \
(last) = resume(prev, next, task_thread_info(next), __fpsave); \
- disable_msa(); \
} while (0)
#define finish_arch_switch(prev) \
diff --git a/arch/mips/kernel/r4k_switch.S b/arch/mips/kernel/r4k_switch.S
index 04cbbde3521b..7dbb64656bfe 100644
--- a/arch/mips/kernel/r4k_switch.S
+++ b/arch/mips/kernel/r4k_switch.S
@@ -25,6 +25,7 @@
/* preprocessor replaces the fp in ".set fp=64" with $30 otherwise */
#undef fp
+#define t4 $12
/*
* Offset to the current process status flags, the first 32 bytes of the
* stack are not used.
@@ -73,6 +74,11 @@
cfc1 t1, fcr31
msa_save_all a0
.set pop /* SET_HARDFLOAT */
+ li t4, MIPS_CONF5_MSAEN
+ mfc0 t3, CP0_CONFIG, 5
+ or t3, t3, t4
+ xor t3, t3, t4
+ mtc0 t3, CP0_CONFIG, 5
sw t1, THREAD_FCR31(a0)
b 2f
