| Message ID | 20210122202144.2756381-3-seanjc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: SVM: Misc SEV cleanups | expand |
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.lendacky@amd.com> > Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Tom Lendacky <thomas.lendacky@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; >
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;
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.lendacky@amd.com> Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/x86/kvm/svm/sev.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)