MIPS: save/disable MSA in lose_fpu
The kernel depends upon MSA never being enabled when the FPU is not, a
condition which is currently violated in a few places (whilst saving
sigcontext, following mips_cpu_save). Catch all the problem cases by
disabling MSA in lose_fpu, after saving context if necessary.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7302/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/include/asm/fpu.h b/arch/mips/include/asm/fpu.h
index a939574..71d97eb 100644
--- a/arch/mips/include/asm/fpu.h
+++ b/arch/mips/include/asm/fpu.h
@@ -21,6 +21,7 @@
#include <asm/hazards.h>
#include <asm/processor.h>
#include <asm/current.h>
+#include <asm/msa.h>
#ifdef CONFIG_MIPS_MT_FPAFF
#include <asm/mips_mt.h>
@@ -141,13 +142,21 @@
static inline void lose_fpu(int save)
{
preempt_disable();
- if (is_fpu_owner()) {
+ if (is_msa_enabled()) {
+ if (save) {
+ save_msa(current);
+ asm volatile("cfc1 %0, $31"
+ : "=r"(current->thread.fpu.fcr31));
+ }
+ disable_msa();
+ clear_thread_flag(TIF_USEDMSA);
+ } else if (is_fpu_owner()) {
if (save)
_save_fp(current);
- KSTK_STATUS(current) &= ~ST0_CU1;
- clear_thread_flag(TIF_USEDFPU);
__disable_fpu();
}
+ KSTK_STATUS(current) &= ~ST0_CU1;
+ clear_thread_flag(TIF_USEDFPU);
preempt_enable();
}