Re: [PATCH 01/13] KVM: SVM: Free sev_asid_bitmap during init if SEV setup fails

[Tom Lendacky]

On 1/8/21 6:47 PM, Sean Christopherson wrote:
Free sev_asid_bitmap if the reclaim bitmap allocation fails, othwerise
it will be leaked as sev_hardware_teardown() frees the bitmaps if and
only if SEV is fully enabled (which obviously isn't the case if SEV
setup fails).

The svm_sev_enabled() function is only based on CONFIG_KVM_AMD_SEV and 
max_sev_asid. So sev_hardware_teardown() should still free everything if 
it was allocated since we never change max_sev_asid, no?

Thanks,
Tom


Fixes: 33af3a7ef9e6 ("KVM: SVM: Reduce WBINVD/DF_FLUSH invocations")
Cc: Tom Lendacky <thomas.lenda...@amd.com>
Cc: sta...@vger.kernel.org
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);
                goto out;
+       }
  
  	pr_info("SEV supported: %u ASIDs\n", max_sev_asid - min_sev_asid + 1);
        sev_supported = true;