aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/lguest/x86
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/lguest/x86')
-rw-r--r--drivers/lguest/x86/core.c15
1 files changed, 9 insertions, 6 deletions
diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c
index 5126d5d9ea0e..2e554a4ab337 100644
--- a/drivers/lguest/x86/core.c
+++ b/drivers/lguest/x86/core.c
@@ -176,7 +176,7 @@ void lguest_arch_run_guest(struct lg_cpu *cpu)
* we set it now, so we can trap and pass that trap to the Guest if it
* uses the FPU. */
if (cpu->ts)
- lguest_set_ts();
+ unlazy_fpu(current);
/* SYSENTER is an optimized way of doing system calls. We can't allow
* it because it always jumps to privilege level 0. A normal Guest
@@ -196,6 +196,10 @@ void lguest_arch_run_guest(struct lg_cpu *cpu)
* trap made the switcher code come back, and an error code which some
* traps set. */
+ /* Restore SYSENTER if it's supposed to be on. */
+ if (boot_cpu_has(X86_FEATURE_SEP))
+ wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0);
+
/* If the Guest page faulted, then the cr2 register will tell us the
* bad virtual address. We have to grab this now, because once we
* re-enable interrupts an interrupt could fault and thus overwrite
@@ -203,13 +207,12 @@ void lguest_arch_run_guest(struct lg_cpu *cpu)
if (cpu->regs->trapnum == 14)
cpu->arch.last_pagefault = read_cr2();
/* Similarly, if we took a trap because the Guest used the FPU,
- * we have to restore the FPU it expects to see. */
+ * we have to restore the FPU it expects to see.
+ * math_state_restore() may sleep and we may even move off to
+ * a different CPU. So all the critical stuff should be done
+ * before this. */
else if (cpu->regs->trapnum == 7)
math_state_restore();
-
- /* Restore SYSENTER if it's supposed to be on. */
- if (boot_cpu_has(X86_FEATURE_SEP))
- wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0);
}
/*H:130 Now we've examined the hypercall code; our Guest can make requests.

Privacy Policy