[PATCH 4/5] powerpc: Remove redundant clear of MSR_VSX in __giveup_vsx()
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2017-08-16 06:01:31
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
__giveup_fpu() already does it and we cannot have MSR_VSX set without having MSR_FP also set. This also adds a warning to check we indeed do Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- arch/powerpc/kernel/process.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index bfbd6083f841..fc285fab7118 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c@@ -331,11 +331,19 @@ static inline int restore_altivec(struct task_struct *tsk) { return 0; } #ifdef CONFIG_VSX static void __giveup_vsx(struct task_struct *tsk) { - if (tsk->thread.regs->msr & MSR_FP) + unsigned long msr = tsk->thread.regs->msr; + + /* + * We should never be ssetting MSR_VSX without also setting + * MSR_FP and MSR_VEC + */ + WARN_ON((msr & MSR_VSX) && !((msr & MSR_FP) && (msr & MSR_VEC))); + + /* __giveup_fpu will clear MSR_VSX */ + if (msr & MSR_FP) __giveup_fpu(tsk); - if (tsk->thread.regs->msr & MSR_VEC) + if (msr & MSR_VEC) __giveup_altivec(tsk); - tsk->thread.regs->msr &= ~MSR_VSX; } static void giveup_vsx(struct task_struct *tsk)
--
2.13.4