On 4/24/2020 3:09 AM, Sean Christopherson wrote:
On Thu, Apr 16, 2020 at 06:15:07PM +0800, Xiaoyao Li wrote:
To make it more clear that the flag means DRn (except DR7) need to be
reloaded before vm entry.
Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 2 +-
arch/x86/kvm/x86.c | 6 +++---
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index c7da23aed79a..f465c76e6e5a 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -511,7 +511,7 @@ struct kvm_pmu_ops;
enum {
KVM_DEBUGREG_BP_ENABLED = 1,
KVM_DEBUGREG_WONT_EXIT = 2,
- KVM_DEBUGREG_RELOAD = 4,
+ KVM_DEBUGREG_NEED_RELOAD = 4,
My vote would be for KVM_DEBUGREG_DIRTY Any bit that is set switch_db_regs
triggers a reload, whereas I would expect a RELOAD flag to be set _every_
time a load is needed and thus be the only bit that's checked
That's what I intended to do with this series, apparently I failed it. :(
};
struct kvm_mtrr_range {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index de77bc9bd0d7..cce926658d10 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1067,7 +1067,7 @@ static void kvm_update_dr0123(struct kvm_vcpu *vcpu)
if (!(vcpu->guest_debug & KVM_GUESTDBG_USE_HW_BP)) {
for (i = 0; i < KVM_NR_DB_REGS; i++)
vcpu->arch.eff_db[i] = vcpu->arch.db[i];
- vcpu->arch.switch_db_regs |= KVM_DEBUGREG_RELOAD;
+ vcpu->arch.switch_db_regs |= KVM_DEBUGREG_NEED_RELOAD;
}
}
@@ -8407,7 +8407,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
set_debugreg(vcpu->arch.eff_db[2], 2);
set_debugreg(vcpu->arch.eff_db[3], 3);
set_debugreg(vcpu->arch.dr6, 6);
- vcpu->arch.switch_db_regs &= ~KVM_DEBUGREG_RELOAD;
+ vcpu->arch.switch_db_regs &= ~KVM_DEBUGREG_NEED_RELOAD;
}
kvm_x86_ops.run(vcpu);
@@ -8424,7 +8424,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
kvm_update_dr0123(vcpu);
kvm_update_dr6(vcpu);
kvm_update_dr7(vcpu);
- vcpu->arch.switch_db_regs &= ~KVM_DEBUGREG_RELOAD;
+ vcpu->arch.switch_db_regs &= ~KVM_DEBUGREG_NEED_RELOAD;
This is the path that I think would really benefit from DIRTY, it took me
several reads to catch that kvm_update_dr0123() will set RELOAD.
}
/*
--
2.20.1
