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KVM: VMX: switch blocked_vcpu_on_cpu_lock to raw spinlock

Browse source 
commit 5f02ef741a upstream.

blocked_vcpu_on_cpu_lock is taken from hard interrupt context
(pi_wakeup_handler), therefore it cannot sleep.

Switch it to a raw spinlock.

Fixes:

[41297.066254] BUG: scheduling while atomic: CPU 0/KVM/635218/0x00010001
[41297.066323] Preemption disabled at:
[41297.066324] [<ffffffff902ee47f>] irq_enter_rcu+0xf/0x60
[41297.066339] Call Trace:
[41297.066342]  <IRQ>
[41297.066346]  dump_stack_lvl+0x34/0x44
[41297.066353]  ? irq_enter_rcu+0xf/0x60
[41297.066356]  __schedule_bug.cold+0x7d/0x8b
[41297.066361]  __schedule+0x439/0x5b0
[41297.066365]  ? task_blocks_on_rt_mutex.constprop.0.isra.0+0x1b0/0x440
[41297.066369]  schedule_rtlock+0x1e/0x40
[41297.066371]  rtlock_slowlock_locked+0xf1/0x260
[41297.066374]  rt_spin_lock+0x3b/0x60
[41297.066378]  pi_wakeup_handler+0x31/0x90 [kvm_intel]
[41297.066388]  sysvec_kvm_posted_intr_wakeup_ipi+0x9d/0xd0
[41297.066392]  </IRQ>
[41297.066392]  asm_sysvec_kvm_posted_intr_wakeup_ipi+0x12/0x20
...

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Marcelo Tosatti 2022-01-18 04:34:43 -05:00 committed by Greg Kroah-Hartman
parent a88ebc49c6
commit 91b7cbea9e
1 changed files with 8 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

16
arch/x86/kvm/vmx/posted_intr.c
View file

@ -15,7 +15,7 @@
* can find which vCPU should be waken up. * can find which vCPU should be waken up.
*/ */
static DEFINE_PER_CPU(struct list_head, blocked_vcpu_on_cpu); static DEFINE_PER_CPU(struct list_head, blocked_vcpu_on_cpu);
static DEFINE_PER_CPU(spinlock_t, blocked_vcpu_on_cpu_lock); static DEFINE_PER_CPU(raw_spinlock_t, blocked_vcpu_on_cpu_lock);
static inline struct pi_desc *vcpu_to_pi_desc(struct kvm_vcpu *vcpu) static inline struct pi_desc *vcpu_to_pi_desc(struct kvm_vcpu *vcpu)
{ {
@ -121,9 +121,9 @@ static void __pi_post_block(struct kvm_vcpu *vcpu)
new.control) != old.control); new.control) != old.control);
if (!WARN_ON_ONCE(vcpu->pre_pcpu == -1)) { if (!WARN_ON_ONCE(vcpu->pre_pcpu == -1)) {
spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); raw_spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu));
list_del(&vcpu->blocked_vcpu_list); list_del(&vcpu->blocked_vcpu_list);
spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); raw_spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu));
vcpu->pre_pcpu = -1; vcpu->pre_pcpu = -1;
} }
} }
@ -154,11 +154,11 @@ int pi_pre_block(struct kvm_vcpu *vcpu)
local_irq_disable(); local_irq_disable();
if (!WARN_ON_ONCE(vcpu->pre_pcpu != -1)) { if (!WARN_ON_ONCE(vcpu->pre_pcpu != -1)) {
vcpu->pre_pcpu = vcpu->cpu; vcpu->pre_pcpu = vcpu->cpu;
spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); raw_spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu));
list_add_tail(&vcpu->blocked_vcpu_list, list_add_tail(&vcpu->blocked_vcpu_list,
&per_cpu(blocked_vcpu_on_cpu, &per_cpu(blocked_vcpu_on_cpu,
vcpu->pre_pcpu)); vcpu->pre_pcpu));
spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu)); raw_spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, vcpu->pre_pcpu));
} }
do { do {
@ -215,7 +215,7 @@ void pi_wakeup_handler(void)
struct kvm_vcpu *vcpu; struct kvm_vcpu *vcpu;
int cpu = smp_processor_id(); int cpu = smp_processor_id();
spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, cpu)); raw_spin_lock(&per_cpu(blocked_vcpu_on_cpu_lock, cpu));
list_for_each_entry(vcpu, &per_cpu(blocked_vcpu_on_cpu, cpu), list_for_each_entry(vcpu, &per_cpu(blocked_vcpu_on_cpu, cpu),
blocked_vcpu_list) { blocked_vcpu_list) {
struct pi_desc *pi_desc = vcpu_to_pi_desc(vcpu); struct pi_desc *pi_desc = vcpu_to_pi_desc(vcpu);
@ -223,13 +223,13 @@ void pi_wakeup_handler(void)
if (pi_test_on(pi_desc) == 1) if (pi_test_on(pi_desc) == 1)
kvm_vcpu_kick(vcpu); kvm_vcpu_kick(vcpu);
} }
spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, cpu)); raw_spin_unlock(&per_cpu(blocked_vcpu_on_cpu_lock, cpu));
} }
void __init pi_init_cpu(int cpu) void __init pi_init_cpu(int cpu)
{ {
INIT_LIST_HEAD(&per_cpu(blocked_vcpu_on_cpu, cpu)); INIT_LIST_HEAD(&per_cpu(blocked_vcpu_on_cpu, cpu));
spin_lock_init(&per_cpu(blocked_vcpu_on_cpu_lock, cpu)); raw_spin_lock_init(&per_cpu(blocked_vcpu_on_cpu_lock, cpu));
} }
bool pi_has_pending_interrupt(struct kvm_vcpu *vcpu) bool pi_has_pending_interrupt(struct kvm_vcpu *vcpu)