[PATCH v4 09/10] x86/xsaves: Fix xstate_offsets, xstate_sizes for legacy components

[Yu-cheng Yu]

The arrays xstate_offsets[] and xstate_sizes[] record XSAVE area 
offsets and sizes. Values for legacy components i387 and XMMs were
not initialized. Fix it.

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx>
---
 arch/x86/kernel/fpu/xstate.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 2e80d6f..06618ea 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -228,6 +228,15 @@ static void __init setup_xstate_features(void)
 	/* start at the beginnning of the "extended state" */
 	unsigned int last_good_offset = offsetof(struct xregs_state,
 						 extended_state_area);
+	/*
+	 * The FP xstates and SSE xstates are legacy states. They are always
+	 * in the fixed offsets in the xsave area in either compacted form
+	 * or standard form.
+	 */
+	xstate_offsets[0] = 0;
+	xstate_sizes[0] = offsetof(struct fxregs_state, xmm_space);
+	xstate_offsets[1] = xstate_sizes[0];
+	xstate_sizes[1] = FIELD_SIZEOF(struct fxregs_state, xmm_space);
 
 	for (i = FIRST_EXTENDED_XFEATURE; i < XFEATURE_MAX; i++) {
 		if (!xfeature_enabled(i))
-- 
1.9.1