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authorWanpeng Li <wanpengli@tencent.com>2018-03-25 07:17:24 +0300
committerRadim Krčmář <rkrcmar@redhat.com>2018-03-28 23:47:06 +0300
commit34226b6b70980a8f81fff3c09a2c889f77edeeff (patch)
tree7cfc7a30d9fb250150ec97697cfab186f8fb5f5e /arch/x86/kernel/kvm.c
parent1f97e01a385703c18ceb853c894ea09736161233 (diff)
downloadlinux-34226b6b70980a8f81fff3c09a2c889f77edeeff.tar.xz
KVM: X86: Fix setup the virt_spin_lock_key before static key get initialized
static_key_disable_cpuslocked(): static key 'virt_spin_lock_key+0x0/0x20' used before call to jump_label_init() WARNING: CPU: 0 PID: 0 at kernel/jump_label.c:161 static_key_disable_cpuslocked+0x61/0x80 RIP: 0010:static_key_disable_cpuslocked+0x61/0x80 Call Trace: static_key_disable+0x16/0x20 start_kernel+0x192/0x4b3 secondary_startup_64+0xa5/0xb0 Qspinlock will be choosed when dedicated pCPUs are available, however, the static virt_spin_lock_key is set in kvm_spinlock_init() before jump_label_init() has been called, which will result in a WARN(). This patch fixes it by delaying the virt_spin_lock_key setup to .smp_prepare_cpus(). Reported-by: Davidlohr Bueso <dbueso@suse.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Fixes: b2798ba0b876 ("KVM: X86: Choose qspinlock when dedicated physical CPUs are available") Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Diffstat (limited to 'arch/x86/kernel/kvm.c')
-rw-r--r--arch/x86/kernel/kvm.c12
1 files changed, 9 insertions, 3 deletions
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 4ccbff63cb86..747c61be0f51 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -454,6 +454,13 @@ static void __init sev_map_percpu_data(void)
}
#ifdef CONFIG_SMP
+static void __init kvm_smp_prepare_cpus(unsigned int max_cpus)
+{
+ native_smp_prepare_cpus(max_cpus);
+ if (kvm_para_has_hint(KVM_HINTS_DEDICATED))
+ static_branch_disable(&virt_spin_lock_key);
+}
+
static void __init kvm_smp_prepare_boot_cpu(void)
{
/*
@@ -557,6 +564,7 @@ static void __init kvm_guest_init(void)
kvm_setup_vsyscall_timeinfo();
#ifdef CONFIG_SMP
+ smp_ops.smp_prepare_cpus = kvm_smp_prepare_cpus;
smp_ops.smp_prepare_boot_cpu = kvm_smp_prepare_boot_cpu;
if (cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/kvm:online",
kvm_cpu_online, kvm_cpu_down_prepare) < 0)
@@ -737,10 +745,8 @@ void __init kvm_spinlock_init(void)
if (!kvm_para_has_feature(KVM_FEATURE_PV_UNHALT))
return;
- if (kvm_para_has_hint(KVM_HINTS_DEDICATED)) {
- static_branch_disable(&virt_spin_lock_key);
+ if (kvm_para_has_hint(KVM_HINTS_DEDICATED))
return;
- }
__pv_init_lock_hash();
pv_lock_ops.queued_spin_lock_slowpath = __pv_queued_spin_lock_slowpath;