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| author | Halil Pasic <pasic@linux.ibm.com> | 2021-08-27 14:54:29 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-09-22 11:48:12 +0200 |
| commit | 3d95bdee23e92568710530f1eca161ccd63db39f (patch) | |
| tree | 4118dff73995290aa017c1a6e612f48f5c3350f5 | |
| parent | c48402015e02901ff8b1fac5c112b02546364bb6 (diff) | |
| download | linux-stable-3d95bdee23e92568710530f1eca161ccd63db39f.tar.gz linux-stable-3d95bdee23e92568710530f1eca161ccd63db39f.tar.bz2 linux-stable-3d95bdee23e92568710530f1eca161ccd63db39f.zip | |
KVM: s390: index kvm->arch.idle_mask by vcpu_idx
commit a3e03bc1368c1bc16e19b001fc96dc7430573cc8 upstream.
While in practice vcpu->vcpu_idx == vcpu->vcp_id is often true, it may
not always be, and we must not rely on this. Reason is that KVM decides
the vcpu_idx, userspace decides the vcpu_id, thus the two might not
match.
Currently kvm->arch.idle_mask is indexed by vcpu_id, which implies
that code like
for_each_set_bit(vcpu_id, kvm->arch.idle_mask, online_vcpus) {
vcpu = kvm_get_vcpu(kvm, vcpu_id);
do_stuff(vcpu);
}
is not legit. Reason is that kvm_get_vcpu expects an vcpu_idx, not an
vcpu_id. The trouble is, we do actually use kvm->arch.idle_mask like
this. To fix this problem we have two options. Either use
kvm_get_vcpu_by_id(vcpu_id), which would loop to find the right vcpu_id,
or switch to indexing via vcpu_idx. The latter is preferable for obvious
reasons.
Let us make switch from indexing kvm->arch.idle_mask by vcpu_id to
indexing it by vcpu_idx. To keep gisa_int.kicked_mask indexed by the
same index as idle_mask lets make the same change for it as well.
Fixes: 1ee0bc559dc3 ("KVM: s390: get rid of local_int array")
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Christian Bornträger <borntraeger@de.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: <stable@vger.kernel.org> # 3.15+
Link: https://lore.kernel.org/r/20210827125429.1912577-1-pasic@linux.ibm.com
[borntraeger@de.ibm.com]: change idle mask, remove kicked_mask
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/s390/kvm/interrupt.c | 4 | ||||
| -rw-r--r-- | arch/s390/kvm/kvm-s390.h | 2 |
2 files changed, 3 insertions, 3 deletions
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index 3515f2b55eb9..dc5ecaea30d7 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -318,13 +318,13 @@ static unsigned long deliverable_irqs(struct kvm_vcpu *vcpu) static void __set_cpu_idle(struct kvm_vcpu *vcpu) { kvm_s390_set_cpuflags(vcpu, CPUSTAT_WAIT); - set_bit(vcpu->vcpu_id, vcpu->kvm->arch.float_int.idle_mask); + set_bit(kvm_vcpu_get_idx(vcpu), vcpu->kvm->arch.float_int.idle_mask); } static void __unset_cpu_idle(struct kvm_vcpu *vcpu) { kvm_s390_clear_cpuflags(vcpu, CPUSTAT_WAIT); - clear_bit(vcpu->vcpu_id, vcpu->kvm->arch.float_int.idle_mask); + clear_bit(kvm_vcpu_get_idx(vcpu), vcpu->kvm->arch.float_int.idle_mask); } static void __reset_intercept_indicators(struct kvm_vcpu *vcpu) diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h index 981e3ba97461..0a2ffd5378be 100644 --- a/arch/s390/kvm/kvm-s390.h +++ b/arch/s390/kvm/kvm-s390.h @@ -67,7 +67,7 @@ static inline int is_vcpu_stopped(struct kvm_vcpu *vcpu) static inline int is_vcpu_idle(struct kvm_vcpu *vcpu) { - return test_bit(vcpu->vcpu_id, vcpu->kvm->arch.float_int.idle_mask); + return test_bit(kvm_vcpu_get_idx(vcpu), vcpu->kvm->arch.float_int.idle_mask); } static inline int kvm_is_ucontrol(struct kvm *kvm) |