On 1/22/21 2:21 PM, Sean Christopherson wrote:
Free sev_asid_bitmap if the reclaim bitmap allocation fails, othwerise
KVM will unnecessarily keep the bitmap when SEV is not fully enabled.

Freeing the page is also necessary to avoid introducing a bug when a
future patch eliminates svm_sev_enabled() in favor of using the global
'sev' flag directly.  While sev_hardware_enabled() checks max_sev_asid,
which is true even if KVM setup fails, 'sev' will be true if and only
if KVM setup fully succeeds.

Fixes: 33af3a7ef9e6 ("KVM: SVM: Reduce WBINVD/DF_FLUSH invocations")
Cc: Tom Lendacky <thomas.lenda...@amd.com>
Signed-off-by: Sean Christopherson <sea...@google.com>

Reviewed-by: Tom Lendacky <thomas.lenda...@amd.com>

---
  arch/x86/kvm/svm/sev.c | 5 ++++-
  1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index c8ffdbc81709..ec742dabbd5b 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -1274,8 +1274,11 @@ void __init sev_hardware_setup(void)
                goto out;
sev_reclaim_asid_bitmap = bitmap_zalloc(max_sev_asid, GFP_KERNEL);
-       if (!sev_reclaim_asid_bitmap)
+       if (!sev_reclaim_asid_bitmap) {
+               bitmap_free(sev_asid_bitmap);
+               sev_asid_bitmap = NULL;
                goto out;
+       }
pr_info("SEV supported: %u ASIDs\n", max_sev_asid - min_sev_asid + 1);
        sev_supported = true;

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