===============
commit 82ea046c95a3c3ddcfa058c8a270b9afb6e93700 upstream.
Update comments to reflect what is really going on and add the TWE bit
to the comments in kvm_arm.h.
Also renames the function to kvm_handle_wfx like is done on arm64 for
consistency and uber-correctness.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
arch/arm/include/asm/kvm_arm.h | 1 +
arch/arm/kvm/handle_exit.c | 14 ++++++++------
2 files changed, 9 insertions(+), 6 deletions(-)
@@ -57,6 +57,7 @@
* TSC: Trap SMC
* TSW: Trap cache operations by set/way
* TWI: Trap WFI
+ * TWE: Trap WFE
* TIDCP: Trap L2CTLR/L2ECTLR
* BSU_IS: Upgrade barriers to the inner shareable domain
* FB: Force broadcast of all maintainance operations
@@ -73,15 +73,17 @@ static int handle_dabt_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run)
}
/**
- * kvm_handle_wfi - handle a wait-for-interrupts instruction executed by a guest
+ * kvm_handle_wfx - handle a WFI or WFE instructions trapped in guests
* @vcpu: the vcpu pointer
* @run: the kvm_run structure pointer
*
- * Simply sets the wait_for_interrupts flag on the vcpu structure, which will
- * halt execution of world-switches and schedule other host processes until
- * there is an incoming IRQ or FIQ to the VM.
+ * WFE: Yield the CPU and come back to this vcpu when the scheduler
+ * decides to.
+ * WFI: Simply call kvm_vcpu_block(), which will halt execution of
+ * world-switches and schedule other host processes until there is an
+ * incoming IRQ or FIQ to the VM.
*/
-static int kvm_handle_wfi(struct kvm_vcpu *vcpu, struct kvm_run *run)
+static int kvm_handle_wfx(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
trace_kvm_wfi(*vcpu_pc(vcpu));
if (kvm_vcpu_get_hsr(vcpu) & HSR_WFI_IS_WFE)
@@ -93,7 +95,7 @@ static int kvm_handle_wfi(struct kvm_vcpu *vcpu, struct kvm_run *run)
}
static exit_handle_fn arm_exit_handlers[] = {
- [HSR_EC_WFI] = kvm_handle_wfi,
+ [HSR_EC_WFI] = kvm_handle_wfx,
[HSR_EC_CP15_32] = kvm_handle_cp15_32,
[HSR_EC_CP15_64] = kvm_handle_cp15_64,
[HSR_EC_CP14_MR] = kvm_handle_cp14_access,
From: Christoffer Dall <christoffer.dall@linaro.org> 3.12-stable review patch. If anyone has any objections, please let me know.