1 files changed, 14 insertions, 0 deletions

diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index 45723f1fe19..1f20608d4ca 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -468,9 +468,23 @@ static int save_i387_fxsave(struct _fpstate_ia32 __user *buf)
 
 static int save_i387_xsave(void __user *buf)
 {
+        struct task_struct *tsk = current;
         struct _fpstate_ia32 __user *fx = buf;
         int err = 0;
 
+        /*
+         * For legacy compatible, we always set FP/SSE bits in the bit
+         * vector while saving the state to the user context.
+         * This will enable us capturing any changes(during sigreturn) to
+         * the FP/SSE bits by the legacy applications which don't touch
+         * xstate_bv in the xsave header.
+         *
+         * xsave aware applications can change the xstate_bv in the xsave
+         * header as well as change any contents in the memory layout.
+         * xrestore as part of sigreturn will capture all the changes.
+         */
+        tsk->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE;
+
         if (save_i387_fxsave(fx) < 0)
                 return -1;