* [PATCH 0/2] Fix the allocation of pv cpu mask
@ 2020-09-14 9:11 lihaiwei.kernel
2020-09-14 9:11 ` [PATCH 1/2] KVM: Fix the build error lihaiwei.kernel
2020-09-14 9:11 ` [PATCH 2/2] KVM: Check if __pv_cpu_mask was allocated instead of assigning ops too late lihaiwei.kernel
0 siblings, 2 replies; 6+ messages in thread
From: lihaiwei.kernel @ 2020-09-14 9:11 UTC (permalink / raw)
To: linux-kernel, kvm, x86
Cc: pbonzini, sean.j.christopherson, vkuznets, wanpengli, jmattson,
joro, tglx, mingo, bp, hpa, lihaiwei
From: Haiwei Li <lihaiwei@tencent.com>
Hi,
There is a old version patch of 'KVM: Check the allocation of pv cpu mask'
in upstream. The v2 and what is discussed is in url:
https://lore.kernel.org/kvm/87o8mlooki.fsf@vitty.brq.redhat.com/
In this patch, i fix the build error and make changes as suggested.
Haiwei Li (2):
KVM: Fix the build error
KVM: Check if __pv_cpu_mask was allocated instead of assigning ops too
late
arch/x86/kernel/kvm.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
--
2.18.4
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/2] KVM: Fix the build error
2020-09-14 9:11 [PATCH 0/2] Fix the allocation of pv cpu mask lihaiwei.kernel
@ 2020-09-14 9:11 ` lihaiwei.kernel
2020-09-20 13:09 ` Paolo Bonzini
2020-09-14 9:11 ` [PATCH 2/2] KVM: Check if __pv_cpu_mask was allocated instead of assigning ops too late lihaiwei.kernel
1 sibling, 1 reply; 6+ messages in thread
From: lihaiwei.kernel @ 2020-09-14 9:11 UTC (permalink / raw)
To: linux-kernel, kvm, x86
Cc: pbonzini, sean.j.christopherson, vkuznets, wanpengli, jmattson,
joro, tglx, mingo, bp, hpa, lihaiwei, kernel test robot
From: Haiwei Li <lihaiwei@tencent.com>
When CONFIG_SMP is not set, an build error occurs with message "error:
use of undeclared identifier 'kvm_send_ipi_mask_allbutself'"
Fixes: 0f990222108d ("KVM: Check the allocation of pv cpu mask", 2020-09-01)
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Haiwei Li <lihaiwei@tencent.com>
---
arch/x86/kernel/kvm.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 1b51b727b140..7e8be0421720 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -797,7 +797,9 @@ static __init int kvm_alloc_cpumask(void)
}
}
+#if defined(CONFIG_SMP)
apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
+#endif
pv_ops.mmu.flush_tlb_others = kvm_flush_tlb_others;
return 0;
--
2.18.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/2] KVM: Check if __pv_cpu_mask was allocated instead of assigning ops too late
2020-09-14 9:11 [PATCH 0/2] Fix the allocation of pv cpu mask lihaiwei.kernel
2020-09-14 9:11 ` [PATCH 1/2] KVM: Fix the build error lihaiwei.kernel
@ 2020-09-14 9:11 ` lihaiwei.kernel
1 sibling, 0 replies; 6+ messages in thread
From: lihaiwei.kernel @ 2020-09-14 9:11 UTC (permalink / raw)
To: linux-kernel, kvm, x86
Cc: pbonzini, sean.j.christopherson, vkuznets, wanpengli, jmattson,
joro, tglx, mingo, bp, hpa, lihaiwei
From: Haiwei Li <lihaiwei@tencent.com>
Without this patch, kvm_flush_tlb_others is not called. We can always check
if __pv_cpu_mask was allocated and revert back to the architectural path if
not.
Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Haiwei Li <lihaiwei@tencent.com>
---
arch/x86/kernel/kvm.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 7e8be0421720..3c6c516d9828 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -553,7 +553,6 @@ static void kvm_send_ipi_mask_allbutself(const struct cpumask *mask, int vector)
static void kvm_setup_pv_ipi(void)
{
apic->send_IPI_mask = kvm_send_ipi_mask;
- apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
pr_info("setup PV IPIs\n");
}
@@ -619,6 +618,11 @@ static void kvm_flush_tlb_others(const struct cpumask *cpumask,
struct kvm_steal_time *src;
struct cpumask *flushmask = this_cpu_cpumask_var_ptr(__pv_cpu_mask);
+ if (unlikely(!flushmask)) {
+ native_flush_tlb_others(cpumask, info);
+ return;
+ }
+
cpumask_copy(flushmask, cpumask);
/*
* We have to call flush only on online vCPUs. And
@@ -652,6 +656,7 @@ static void __init kvm_guest_init(void)
}
if (pv_tlb_flush_supported()) {
+ pv_ops.mmu.flush_tlb_others = kvm_flush_tlb_others;
pv_ops.mmu.tlb_remove_table = tlb_remove_table;
pr_info("KVM setup pv remote TLB flush\n");
}
@@ -800,7 +805,6 @@ static __init int kvm_alloc_cpumask(void)
#if defined(CONFIG_SMP)
apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
#endif
- pv_ops.mmu.flush_tlb_others = kvm_flush_tlb_others;
return 0;
zalloc_cpumask_fail:
--
2.18.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] KVM: Fix the build error
2020-09-14 9:11 ` [PATCH 1/2] KVM: Fix the build error lihaiwei.kernel
@ 2020-09-20 13:09 ` Paolo Bonzini
2020-09-21 0:23 ` Haiwei Li
2020-09-23 5:02 ` Haiwei Li
0 siblings, 2 replies; 6+ messages in thread
From: Paolo Bonzini @ 2020-09-20 13:09 UTC (permalink / raw)
To: lihaiwei.kernel, linux-kernel, kvm, x86
Cc: sean.j.christopherson, vkuznets, wanpengli, jmattson, joro, tglx,
mingo, bp, hpa, lihaiwei, kernel test robot
On 14/09/20 11:11, lihaiwei.kernel@gmail.com wrote:
> From: Haiwei Li <lihaiwei@tencent.com>
>
> When CONFIG_SMP is not set, an build error occurs with message "error:
> use of undeclared identifier 'kvm_send_ipi_mask_allbutself'"
>
> Fixes: 0f990222108d ("KVM: Check the allocation of pv cpu mask", 2020-09-01)
> Reported-by: kernel test robot <lkp@intel.com>
> Signed-off-by: Haiwei Li <lihaiwei@tencent.com>
> ---
> arch/x86/kernel/kvm.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
> index 1b51b727b140..7e8be0421720 100644
> --- a/arch/x86/kernel/kvm.c
> +++ b/arch/x86/kernel/kvm.c
> @@ -797,7 +797,9 @@ static __init int kvm_alloc_cpumask(void)
> }
> }
>
> +#if defined(CONFIG_SMP)
> apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
> +#endif
> pv_ops.mmu.flush_tlb_others = kvm_flush_tlb_others;
> return 0;
>
>
If CONFIG_SMP is not set you don't need kvm_alloc_cpumask or
pv_ops.mmu.flush_tlb_others at all. Can you squash these two into the
original patch and re-submit for 5.10?
Paolo
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] KVM: Fix the build error
2020-09-20 13:09 ` Paolo Bonzini
@ 2020-09-21 0:23 ` Haiwei Li
2020-09-23 5:02 ` Haiwei Li
1 sibling, 0 replies; 6+ messages in thread
From: Haiwei Li @ 2020-09-21 0:23 UTC (permalink / raw)
To: Paolo Bonzini, linux-kernel, kvm, x86
Cc: sean.j.christopherson, vkuznets, wanpengli, jmattson, joro, tglx,
mingo, bp, hpa, lihaiwei, kernel test robot
On 20/9/20 21:09, Paolo Bonzini wrote:
> On 14/09/20 11:11, lihaiwei.kernel@gmail.com wrote:
>> From: Haiwei Li <lihaiwei@tencent.com>
>>
>> When CONFIG_SMP is not set, an build error occurs with message "error:
>> use of undeclared identifier 'kvm_send_ipi_mask_allbutself'"
>>
>> Fixes: 0f990222108d ("KVM: Check the allocation of pv cpu mask", 2020-09-01)
>> Reported-by: kernel test robot <lkp@intel.com>
>> Signed-off-by: Haiwei Li <lihaiwei@tencent.com>
>> ---
>> arch/x86/kernel/kvm.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
>> index 1b51b727b140..7e8be0421720 100644
>> --- a/arch/x86/kernel/kvm.c
>> +++ b/arch/x86/kernel/kvm.c
>> @@ -797,7 +797,9 @@ static __init int kvm_alloc_cpumask(void)
>> }
>> }
>>
>> +#if defined(CONFIG_SMP)
>> apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
>> +#endif
>> pv_ops.mmu.flush_tlb_others = kvm_flush_tlb_others;
>> return 0;
>>
>>
>
> If CONFIG_SMP is not set you don't need kvm_alloc_cpumask or
> pv_ops.mmu.flush_tlb_others at all. Can you squash these two into the
> original patch and re-submit for 5.10?
I will, thanks.
Haiwei Li
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 1/2] KVM: Fix the build error
2020-09-20 13:09 ` Paolo Bonzini
2020-09-21 0:23 ` Haiwei Li
@ 2020-09-23 5:02 ` Haiwei Li
1 sibling, 0 replies; 6+ messages in thread
From: Haiwei Li @ 2020-09-23 5:02 UTC (permalink / raw)
To: Paolo Bonzini, linux-kernel, kvm, x86
Cc: sean.j.christopherson, vkuznets, wanpengli, jmattson, joro, tglx,
mingo, bp, hpa, lihaiwei, kernel test robot
On 20/9/20 21:09, Paolo Bonzini wrote:
> On 14/09/20 11:11, lihaiwei.kernel@gmail.com wrote:
>> From: Haiwei Li <lihaiwei@tencent.com>
>>
>> When CONFIG_SMP is not set, an build error occurs with message "error:
>> use of undeclared identifier 'kvm_send_ipi_mask_allbutself'"
>>
>> Fixes: 0f990222108d ("KVM: Check the allocation of pv cpu mask", 2020-09-01)
>> Reported-by: kernel test robot <lkp@intel.com>
>> Signed-off-by: Haiwei Li <lihaiwei@tencent.com>
>> ---
>> arch/x86/kernel/kvm.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
>> index 1b51b727b140..7e8be0421720 100644
>> --- a/arch/x86/kernel/kvm.c
>> +++ b/arch/x86/kernel/kvm.c
>> @@ -797,7 +797,9 @@ static __init int kvm_alloc_cpumask(void)
>> }
>> }
>>
>> +#if defined(CONFIG_SMP)
>> apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
>> +#endif
>> pv_ops.mmu.flush_tlb_others = kvm_flush_tlb_others;
>> return 0;
>>
>>
>
> If CONFIG_SMP is not set you don't need kvm_alloc_cpumask or
> pv_ops.mmu.flush_tlb_others at all. Can you squash these two into the
> original patch and re-submit for 5.10?
Hi, Paolo
I'm a little confused. Function kvm_flush_tlb_others doesn't seem to be
related to CONFIG_SMP.
And my patch like:
---
arch/x86/kernel/kvm.c | 27 ++++++++++++++++++++++++---
1 file changed, 24 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 9663ba31347c..1e5da6db519c 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -553,7 +553,6 @@ static void kvm_send_ipi_mask_allbutself(const
struct cpumask *mask, int vector)
static void kvm_setup_pv_ipi(void)
{
apic->send_IPI_mask = kvm_send_ipi_mask;
- apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
pr_info("setup PV IPIs\n");
}
@@ -619,6 +618,11 @@ static void kvm_flush_tlb_others(const struct
cpumask *cpumask,
struct kvm_steal_time *src;
struct cpumask *flushmask = this_cpu_cpumask_var_ptr(__pv_cpu_mask);
+ if (unlikely(!flushmask)) {
+ native_flush_tlb_others(cpumask, info);
+ return;
+ }
+
cpumask_copy(flushmask, cpumask);
/*
* We have to call flush only on online vCPUs. And
@@ -765,6 +769,14 @@ static __init int activate_jump_labels(void)
}
arch_initcall(activate_jump_labels);
+static void kvm_free_cpumask(void)
+{
+ unsigned int cpu;
+
+ for_each_possible_cpu(cpu)
+ free_cpumask_var(per_cpu(__pv_cpu_mask, cpu));
+}
+
static __init int kvm_alloc_cpumask(void)
{
int cpu;
@@ -783,11 +795,20 @@ static __init int kvm_alloc_cpumask(void)
if (alloc)
for_each_possible_cpu(cpu) {
- zalloc_cpumask_var_node(per_cpu_ptr(&__pv_cpu_mask, cpu),
- GFP_KERNEL, cpu_to_node(cpu));
+ if (!zalloc_cpumask_var_node(
+ per_cpu_ptr(&__pv_cpu_mask, cpu),
+ GFP_KERNEL, cpu_to_node(cpu)))
+ goto zalloc_cpumask_fail;
}
+#if defined(CONFIG_SMP)
+ apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
+#endif
return 0;
+
+zalloc_cpumask_fail:
+ kvm_free_cpumask();
+ return -ENOMEM;
}
arch_initcall(kvm_alloc_cpumask);
--
2.18.4
Do you have any suggestion? Thanks.
Haiwei
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-09-23 5:02 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-09-14 9:11 [PATCH 0/2] Fix the allocation of pv cpu mask lihaiwei.kernel
2020-09-14 9:11 ` [PATCH 1/2] KVM: Fix the build error lihaiwei.kernel
2020-09-20 13:09 ` Paolo Bonzini
2020-09-21 0:23 ` Haiwei Li
2020-09-23 5:02 ` Haiwei Li
2020-09-14 9:11 ` [PATCH 2/2] KVM: Check if __pv_cpu_mask was allocated instead of assigning ops too late lihaiwei.kernel
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