powerpc: Fix VSX enabling/flushing to also test MSR_FP and MSR_VEC

commit 5a69aec945d27e78abac9fd032533d3aaebf7c1e upstream.

VSX uses a combination of the old vector registers, the old FP
registers and new "second halves" of the FP registers.

Thus when we need to see the VSX state in the thread struct
(flush_vsx_to_thread()) or when we'll use the VSX in the kernel
(enable_kernel_vsx()) we need to ensure they are all flushed into
the thread struct if either of them is individually enabled.

Unfortunately we only tested if the whole VSX was enabled, not if they
were individually enabled.

Fixes: 72cd7b44bc99 ("powerpc: Uncomment and make enable_kernel_vsx() routine available")
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 2ad725ef4368a3e525681b0ce4a56ef8e960bf48..318738f3aa05d817ca24f3babde742da13d806a6 100644 (file)
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -362,7 +362,8 @@ void enable_kernel_vsx(void)
 
        cpumsr = msr_check_and_set(MSR_FP|MSR_VEC|MSR_VSX);
 
-       if (current->thread.regs && (current->thread.regs->msr & MSR_VSX)) {
+       if (current->thread.regs &&
+           (current->thread.regs->msr & (MSR_VSX|MSR_VEC|MSR_FP))) {
                check_if_tm_restore_required(current);
                /*
                 * If a thread has already been reclaimed then the
@@ -386,7 +387,7 @@ void flush_vsx_to_thread(struct task_struct *tsk)
 {
        if (tsk->thread.regs) {
                preempt_disable();
-               if (tsk->thread.regs->msr & MSR_VSX) {
+               if (tsk->thread.regs->msr & (MSR_VSX|MSR_VEC|MSR_FP)) {
                        BUG_ON(tsk != current);
                        giveup_vsx(tsk);
                }