On 1/13/21 6:36 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> --- arch/x86/kvm/svm/sev.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index c8ffdbc81709..0eeb6e1b803d 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1274,8 +1274,10 @@ 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);
Until that future change, you probably need to do sev_asid_bitmap = NULL here to avoid an issue in sev_hardware_teardown() when it tries to free it again.
Thanks, Tom
goto out; + }pr_info("SEV supported: %u ASIDs\n", max_sev_asid - min_sev_asid + 1);sev_supported = true;
