D44522.id136254.diff
No OneTemporary
Actions

Size

1 KB

Referenced Files

None

Subscribers

None

D44522.id136254.diff
View Options

	diff --git a/sys/amd64/amd64/fpu.c b/sys/amd64/amd64/fpu.c
	--- a/sys/amd64/amd64/fpu.c
	+++ b/sys/amd64/amd64/fpu.c
	@@ -850,7 +850,10 @@
	struct pcb *pcb;
	uint64_t *xstate_bv, bit;
	char *sa;
	+ struct savefpu *s;
	+ uint32_t mxcsr;
	int max_ext_n, i, owned;
	+ bool do_mxcsr;

	pcb = td->td_pcb;
	critical_enter();
	@@ -877,14 +880,29 @@
	xstate_bv = (uint64_t *)(sa + sizeof(struct savefpu) +
	offsetof(struct xstate_hdr, xstate_bv));
	max_ext_n = flsl(xsave_mask);
	+ do_mxcsr = false;
	for (i = 0; i < max_ext_n; i++) {
	bit = 1ULL << i;
	if ((xsave_mask & bit) == 0 \|\| (*xstate_bv & bit) != 0)
	continue;
	+ if (i == 0 && (*xstate_bv & (XFEATURE_ENABLED_SSE \|
	+ XFEATURE_ENABLED_AVX)) != 0) {
	+ /*
	+ * x87 area was not saved by XSAVEOPT,
	+ * but one of XMM or AVX was. Then we need
	+ * to preserve MXCSR from overwriting
	+ * with the default value.
	+ */
	+ s = (struct savefpu *)sa;
	+ mxcsr = s->sv_env.en_mxcsr;
	+ do_mxcsr = true;
	+ }
	bcopy((char *)fpu_initialstate +
	xsave_area_desc[i].offset,
	sa + xsave_area_desc[i].offset,
	xsave_area_desc[i].size);
	+ if (do_mxcsr)
	+ s->sv_env.en_mxcsr = mxcsr;
	*xstate_bv \|= bit;
	}
	}