This is a note to let you know that I've just added the patch titled
kvm: avoid unused variable warning for UP builds
to the 4.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-avoid-unused-variable-warning-for-up-builds.patch
and it can be found in the queue-4.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From b49defe83659cefbb1763d541e779da32594ab10 Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Date: Fri, 30 Jun 2017 13:25:45 +0200
Subject: kvm: avoid unused variable warning for UP builds
From: Paolo Bonzini <pbonzini@xxxxxxxxxx>
commit b49defe83659cefbb1763d541e779da32594ab10 upstream.
The uniprocessor version of smp_call_function_many does not evaluate
all of its argument, and the compiler emits a warning about "wait"
being unused. This breaks the build on architectures for which
"-Werror" is enabled by default.
Work around it by moving the invocation of smp_call_function_many to
its own inline function.
Reported-by: Paul Mackerras <paulus@xxxxxxxxxx>
Fixes: 7a97cec26b94c909f4cbad2dc3186af3e457a522
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
virt/kvm/kvm_main.c | 24 +++++++++++++++---------
1 file changed, 15 insertions(+), 9 deletions(-)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -187,12 +187,23 @@ static void ack_flush(void *_completed)
{
}
+static inline bool kvm_kick_many_cpus(const struct cpumask *cpus, bool wait)
+{
+ if (unlikely(!cpus))
+ cpus = cpu_online_mask;
+
+ if (cpumask_empty(cpus))
+ return false;
+
+ smp_call_function_many(cpus, ack_flush, NULL, wait);
+ return true;
+}
+
bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
{
int i, cpu, me;
cpumask_var_t cpus;
- bool called = true;
- bool wait = req & KVM_REQUEST_WAIT;
+ bool called;
struct kvm_vcpu *vcpu;
zalloc_cpumask_var(&cpus, GFP_ATOMIC);
@@ -207,14 +218,9 @@ bool kvm_make_all_cpus_request(struct kv
if (cpus != NULL && cpu != -1 && cpu != me &&
kvm_request_needs_ipi(vcpu, req))
- cpumask_set_cpu(cpu, cpus);
+ __cpumask_set_cpu(cpu, cpus);
}
- if (unlikely(cpus == NULL))
- smp_call_function_many(cpu_online_mask, ack_flush, NULL, wait);
- else if (!cpumask_empty(cpus))
- smp_call_function_many(cpus, ack_flush, NULL, wait);
- else
- called = false;
+ called = kvm_kick_many_cpus(cpus, !!(req & KVM_REQUEST_WAIT));
put_cpu();
free_cpumask_var(cpus);
return called;
Patches currently in stable-queue which might be from pbonzini@xxxxxxxxxx are
queue-4.12/kvm-avoid-unused-variable-warning-for-up-builds.patch
queue-4.12/kvm-vfio-decouple-only-when-we-match-a-group.patch