Switch to kvm_lock/unlock_all_vcpus instead of arm's own
version.
This fixes lockdep warning about reaching maximum lock depth:
[ 328.171264] BUG: MAX_LOCK_DEPTH too low!
[ 328.175227] turning off the locking correctness validator.
[ 328.180726] Please attach the output of /proc/lock_stat to the bug report
[ 328.187531] depth: 48 max: 48!
[ 328.190678] 48 locks held by qemu-kvm/11664:
[ 328.194957] #0: ffff800086de5ba0 (&kvm->lock){+.+.}-{3:3}, at: kvm_ioctl_create_device+0x174/0x5b0
[ 328.204048] #1: ffff0800e78800b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[ 328.212521] #2: ffff07ffeee51e98 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[ 328.220991] #3: ffff0800dc7d80b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[ 328.229463] #4: ffff07ffe0c980b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[ 328.237934] #5: ffff0800a3883c78 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[ 328.246405] #6: ffff07fffbe480b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
No functional change intended.
Suggested-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
---
arch/arm64/include/asm/kvm_host.h | 3 ---
arch/arm64/kvm/arch_timer.c | 8 +++----
arch/arm64/kvm/arm.c | 32 ---------------------------
arch/arm64/kvm/vgic/vgic-init.c | 11 +++++----
arch/arm64/kvm/vgic/vgic-its.c | 18 ++++++++-------
arch/arm64/kvm/vgic/vgic-kvm-device.c | 21 ++++++++++--------
6 files changed, 33 insertions(+), 60 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 7cfa024de4e3..bba97ea700ca 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -1234,9 +1234,6 @@ int __init populate_sysreg_config(const struct sys_reg_desc *sr,
unsigned int idx);
int __init populate_nv_trap_config(void);
-bool lock_all_vcpus(struct kvm *kvm);
-void unlock_all_vcpus(struct kvm *kvm);
-
void kvm_calculate_traps(struct kvm_vcpu *vcpu);
/* MMIO helpers */
diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
index 231c0cd9c7b4..3af1da807f9c 100644
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@ -1769,7 +1769,9 @@ int kvm_vm_ioctl_set_counter_offset(struct kvm *kvm,
mutex_lock(&kvm->lock);
- if (lock_all_vcpus(kvm)) {
+ ret = kvm_lock_all_vcpus(kvm);
+
+ if (!ret) {
set_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET, &kvm->arch.flags);
/*
@@ -1781,9 +1783,7 @@ int kvm_vm_ioctl_set_counter_offset(struct kvm *kvm,
kvm->arch.timer_data.voffset = offset->counter_offset;
kvm->arch.timer_data.poffset = offset->counter_offset;
- unlock_all_vcpus(kvm);
- } else {
- ret = -EBUSY;
+ kvm_unlock_all_vcpus(kvm);
}
mutex_unlock(&kvm->lock);
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 071a7d75be68..f58849c5b4f0 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1895,38 +1895,6 @@ static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx)
}
}
-void unlock_all_vcpus(struct kvm *kvm)
-{
- lockdep_assert_held(&kvm->lock);
-
- unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1);
-}
-
-/* Returns true if all vcpus were locked, false otherwise */
-bool lock_all_vcpus(struct kvm *kvm)
-{
- struct kvm_vcpu *tmp_vcpu;
- unsigned long c;
-
- lockdep_assert_held(&kvm->lock);
-
- /*
- * Any time a vcpu is in an ioctl (including running), the
- * core KVM code tries to grab the vcpu->mutex.
- *
- * By grabbing the vcpu->mutex of all VCPUs we ensure that no
- * other VCPUs can fiddle with the state while we access it.
- */
- kvm_for_each_vcpu(c, tmp_vcpu, kvm) {
- if (!mutex_trylock(&tmp_vcpu->mutex)) {
- unlock_vcpus(kvm, c - 1);
- return false;
- }
- }
-
- return true;
-}
-
static unsigned long nvhe_percpu_size(void)
{
return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c
index bc7e22ab5d81..8fbce4db5c2e 100644
--- a/arch/arm64/kvm/vgic/vgic-init.c
+++ b/arch/arm64/kvm/vgic/vgic-init.c
@@ -85,8 +85,8 @@ int kvm_vgic_create(struct kvm *kvm, u32 type)
/* Must be held to avoid race with vCPU creation */
lockdep_assert_held(&kvm->lock);
- ret = -EBUSY;
- if (!lock_all_vcpus(kvm))
+ ret = kvm_lock_all_vcpus(kvm);
+ if (ret)
return ret;
mutex_lock(&kvm->arch.config_lock);
@@ -97,9 +97,12 @@ int kvm_vgic_create(struct kvm *kvm, u32 type)
}
kvm_for_each_vcpu(i, vcpu, kvm) {
- if (vcpu_has_run_once(vcpu))
+ if (vcpu_has_run_once(vcpu)) {
+ ret = -EBUSY;
goto out_unlock;
+ }
}
+
ret = 0;
if (type == KVM_DEV_TYPE_ARM_VGIC_V2)
@@ -124,7 +127,7 @@ int kvm_vgic_create(struct kvm *kvm, u32 type)
out_unlock:
mutex_unlock(&kvm->arch.config_lock);
- unlock_all_vcpus(kvm);
+ kvm_unlock_all_vcpus(kvm);
return ret;
}
diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c
index fb96802799c6..02b02b4fff5d 100644
--- a/arch/arm64/kvm/vgic/vgic-its.c
+++ b/arch/arm64/kvm/vgic/vgic-its.c
@@ -1977,7 +1977,7 @@ static int vgic_its_attr_regs_access(struct kvm_device *dev,
struct vgic_its *its;
gpa_t addr, offset;
unsigned int len;
- int align, ret = 0;
+ int align, ret;
its = dev->private;
offset = attr->attr;
@@ -1999,9 +1999,10 @@ static int vgic_its_attr_regs_access(struct kvm_device *dev,
mutex_lock(&dev->kvm->lock);
- if (!lock_all_vcpus(dev->kvm)) {
+ ret = kvm_lock_all_vcpus(sdev->kvm);
+ if (ret) {
mutex_unlock(&dev->kvm->lock);
- return -EBUSY;
+ return ret;
}
mutex_lock(&dev->kvm->arch.config_lock);
@@ -2034,7 +2035,7 @@ static int vgic_its_attr_regs_access(struct kvm_device *dev,
}
out:
mutex_unlock(&dev->kvm->arch.config_lock);
- unlock_all_vcpus(dev->kvm);
+ kvm_unlock_all_vcpus(dev->kvm);
mutex_unlock(&dev->kvm->lock);
return ret;
}
@@ -2697,16 +2698,17 @@ static int vgic_its_has_attr(struct kvm_device *dev,
static int vgic_its_ctrl(struct kvm *kvm, struct vgic_its *its, u64 attr)
{
const struct vgic_its_abi *abi = vgic_its_get_abi(its);
- int ret = 0;
+ int ret;
if (attr == KVM_DEV_ARM_VGIC_CTRL_INIT) /* Nothing to do */
return 0;
mutex_lock(&kvm->lock);
- if (!lock_all_vcpus(kvm)) {
+ ret = kvm_lock_all_vcpus(kvm);
+ if (ret) {
mutex_unlock(&kvm->lock);
- return -EBUSY;
+ return ret;
}
mutex_lock(&kvm->arch.config_lock);
@@ -2726,7 +2728,7 @@ static int vgic_its_ctrl(struct kvm *kvm, struct vgic_its *its, u64 attr)
mutex_unlock(&its->its_lock);
mutex_unlock(&kvm->arch.config_lock);
- unlock_all_vcpus(kvm);
+ kvm_unlock_all_vcpus(kvm);
mutex_unlock(&kvm->lock);
return ret;
}
diff --git a/arch/arm64/kvm/vgic/vgic-kvm-device.c b/arch/arm64/kvm/vgic/vgic-kvm-device.c
index 5f4f57aaa23e..ee70a9d642ed 100644
--- a/arch/arm64/kvm/vgic/vgic-kvm-device.c
+++ b/arch/arm64/kvm/vgic/vgic-kvm-device.c
@@ -268,15 +268,16 @@ static int vgic_set_common_attr(struct kvm_device *dev,
return -ENXIO;
mutex_lock(&dev->kvm->lock);
- if (!lock_all_vcpus(dev->kvm)) {
+ r = kvm_lock_all_vcpus(dev->kvm);
+ if (r) {
mutex_unlock(&dev->kvm->lock);
- return -EBUSY;
+ return r;
}
mutex_lock(&dev->kvm->arch.config_lock);
r = vgic_v3_save_pending_tables(dev->kvm);
mutex_unlock(&dev->kvm->arch.config_lock);
- unlock_all_vcpus(dev->kvm);
+ kvm_unlock_all_vcpus(dev->kvm);
mutex_unlock(&dev->kvm->lock);
return r;
}
@@ -384,9 +385,10 @@ static int vgic_v2_attr_regs_access(struct kvm_device *dev,
mutex_lock(&dev->kvm->lock);
- if (!lock_all_vcpus(dev->kvm)) {
+ ret = kvm_lock_all_vcpus(dev->kvm);
+ if (ret) {
mutex_unlock(&dev->kvm->lock);
- return -EBUSY;
+ return ret;
}
mutex_lock(&dev->kvm->arch.config_lock);
@@ -409,7 +411,7 @@ static int vgic_v2_attr_regs_access(struct kvm_device *dev,
out:
mutex_unlock(&dev->kvm->arch.config_lock);
- unlock_all_vcpus(dev->kvm);
+ kvm_unlock_all_vcpus(dev->kvm);
mutex_unlock(&dev->kvm->lock);
if (!ret && !is_write)
@@ -545,9 +547,10 @@ static int vgic_v3_attr_regs_access(struct kvm_device *dev,
mutex_lock(&dev->kvm->lock);
- if (!lock_all_vcpus(dev->kvm)) {
+ ret = kvm_lock_all_vcpus(dev->kvm);
+ if (ret) {
mutex_unlock(&dev->kvm->lock);
- return -EBUSY;
+ return ret;
}
mutex_lock(&dev->kvm->arch.config_lock);
@@ -589,7 +592,7 @@ static int vgic_v3_attr_regs_access(struct kvm_device *dev,
out:
mutex_unlock(&dev->kvm->arch.config_lock);
- unlock_all_vcpus(dev->kvm);
+ kvm_unlock_all_vcpus(dev->kvm);
mutex_unlock(&dev->kvm->lock);
if (!ret && uaccess && !is_write) {
--
2.26.3
