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| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2020-06-10 19:55:31 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-06-11 12:35:19 -0400 |
| commit | 7863e346e1089b40cac1c7d9098314c405e2e1e3 (patch) | |
| tree | fa4c2c9d3b1d63d7d0ec19e60e02af9dcd7f477d /virt | |
| parent | cd18eaeaffa6e5291cdbcd591334d577c4e897df (diff) | |
| download | linux-stable-7863e346e1089b40cac1c7d9098314c405e2e1e3.tar.gz linux-stable-7863e346e1089b40cac1c7d9098314c405e2e1e3.tar.bz2 linux-stable-7863e346e1089b40cac1c7d9098314c405e2e1e3.zip | |
KVM: async_pf: Cleanup kvm_setup_async_pf()
schedule_work() returns 'false' only when the work is already on the queue
and this can't happen as kvm_setup_async_pf() always allocates a new one.
Also, to avoid potential race, it makes sense to to schedule_work() at the
very end after we've added it to the queue.
While on it, do some minor cleanup. gfn_to_pfn_async() mentioned in a
comment does not currently exist and, moreover, we can check
kvm_is_error_hva() at the very beginning, before we try to allocate work so
'retry_sync' label can go away completely.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200610175532.779793-1-vkuznets@redhat.com>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/async_pf.c | 19 |
1 files changed, 6 insertions, 13 deletions
diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c index f1e07fae84e9..ba080088da76 100644 --- a/virt/kvm/async_pf.c +++ b/virt/kvm/async_pf.c @@ -164,7 +164,9 @@ int kvm_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, if (vcpu->async_pf.queued >= ASYNC_PF_PER_VCPU) return 0; - /* setup delayed work */ + /* Arch specific code should not do async PF in this case */ + if (unlikely(kvm_is_error_hva(hva))) + return 0; /* * do alloc nowait since if we are going to sleep anyway we @@ -183,24 +185,15 @@ int kvm_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, mmget(work->mm); kvm_get_kvm(work->vcpu->kvm); - /* this can't really happen otherwise gfn_to_pfn_async - would succeed */ - if (unlikely(kvm_is_error_hva(work->addr))) - goto retry_sync; - INIT_WORK(&work->work, async_pf_execute); - if (!schedule_work(&work->work)) - goto retry_sync; list_add_tail(&work->queue, &vcpu->async_pf.queue); vcpu->async_pf.queued++; kvm_arch_async_page_not_present(vcpu, work); + + schedule_work(&work->work); + return 1; -retry_sync: - kvm_put_kvm(work->vcpu->kvm); - mmput(work->mm); - kmem_cache_free(async_pf_cache, work); - return 0; } int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu) |