From: Benjamin Herrenschmidt Date: Wed, 16 Aug 2017 06:01:17 +0000 (+1000) Subject: powerpc: Remove redundant clear of MSR_VSX in __giveup_vsx() X-Git-Tag: v4.14-rc1~119^2~195 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=dc801081f2eae57a389bc9230ff4fb0d91487990;p=linux.git powerpc: Remove redundant clear of MSR_VSX in __giveup_vsx() __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 Signed-off-by: Michael Ellerman --- diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 32b58648052f..ff522bf75d53 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)