Commit bc1a34f1 authored by Andrea Arcangeli's avatar Andrea Arcangeli Committed by Avi Kivity

KVM: avoid fx_init() schedule in atomic

This make sure not to schedule in atomic during fx_init. I also
changed the name of fpu_init to fx_finit to avoid duplicating the name
with fpu_init that is already used in the kernel, this makes grep
simpler if nothing else.
Signed-off-by: default avatarAndrea Arcangeli <andrea@qumranet.com>
Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent b4f14abd
...@@ -3703,10 +3703,19 @@ void fx_init(struct kvm_vcpu *vcpu) ...@@ -3703,10 +3703,19 @@ void fx_init(struct kvm_vcpu *vcpu)
{ {
unsigned after_mxcsr_mask; unsigned after_mxcsr_mask;
/*
* Touch the fpu the first time in non atomic context as if
* this is the first fpu instruction the exception handler
* will fire before the instruction returns and it'll have to
* allocate ram with GFP_KERNEL.
*/
if (!used_math())
fx_save(&vcpu->arch.host_fx_image);
/* Initialize guest FPU by resetting ours and saving into guest's */ /* Initialize guest FPU by resetting ours and saving into guest's */
preempt_disable(); preempt_disable();
fx_save(&vcpu->arch.host_fx_image); fx_save(&vcpu->arch.host_fx_image);
fpu_init(); fx_finit();
fx_save(&vcpu->arch.guest_fx_image); fx_save(&vcpu->arch.guest_fx_image);
fx_restore(&vcpu->arch.host_fx_image); fx_restore(&vcpu->arch.host_fx_image);
preempt_enable(); preempt_enable();
......
...@@ -627,7 +627,7 @@ static inline void fx_restore(struct i387_fxsave_struct *image) ...@@ -627,7 +627,7 @@ static inline void fx_restore(struct i387_fxsave_struct *image)
asm("fxrstor (%0)":: "r" (image)); asm("fxrstor (%0)":: "r" (image));
} }
static inline void fpu_init(void) static inline void fx_finit(void)
{ {
asm("finit"); asm("finit");
} }
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment