[Xen-devel] [PATCH RFC] x86/resume: take care of fully eager FPU around system suspend

["Jan Beulich" <jbeulich@xxxxxxxx>]

Just like in the HVM emulation and EFI runtime call cases we must not
set CR0.TS here in fully eager mode. Note that idle vCPU-s never have
->arch.fully_eager_fpu set (for their initialization not going through
vcpu_init_fpu()), so we won't hit the respective ASSERT() in
vcpu_restore_fpu_eager(). 

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
---
RFC: Not even compile tested, as I'm writing this from home. Also please
         excuse the formatting (hence the attachment) - our mail web frontend
      doesn't allow anything better.

--- a/xen/arch/x86/acpi/suspend.c
+++ b/xen/arch/x86/acpi/suspend.c
@@ -92,8 +92,11 @@ void restore_rest_processor_state(void)
         write_debugreg(7, curr->arch.debugreg[7]);
     }
 
-    /* Reload FPU state on next FPU use. */
-    stts();
+    /* Reload FPU state immediately or on next FPU use. */
+    if ( curr->arch.fully_eager_fpu )
+        vcpu_restore_fpu_eager(curr);
+    else
+        stts();
 
     if (cpu_has_pat)
         wrmsrl(MSR_IA32_CR_PAT, host_pat);

Attachment: x86-resume-eager-FPU.patch
Description: Text document

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel