github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-06-05 04:56:13 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

KVM: TDX: Avoid a double-KVM_BUG_ON() in tdx_sept_zap_private_spte()

Browse Source 
Return -EIO immediately from tdx_sept_zap_private_spte() if the number of
to-be-added pages underflows, so that the following "KVM_BUG_ON(err, kvm)"
isn't also triggered.  Isolating the check from the "is premap error"
if-statement will also allow adding a lockdep assertion that premap errors
are encountered if and only if slots_lock is held.

Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Yan Zhao <yan.y.zhao@intel.com>
Tested-by: Yan Zhao <yan.y.zhao@intel.com>
Tested-by: Kai Huang <kai.huang@intel.com>
Link: https://patch.msgid.link/20251030200951.3402865-14-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
This commit is contained in:
Sean Christopherson 2025-10-30 13:09:36 -07:00
parent b9d5cf6de0
commit 24adff3970
1 changed files with 4 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
arch/x86/kvm/vmx/tdx.c
View File

@ -1725,8 +1725,10 @@ static int tdx_sept_zap_private_spte(struct kvm *kvm, gfn_t gfn,
err = tdh_mem_range_block(&kvm_tdx->td, gpa, tdx_level, &entry, &level_state);
tdx_no_vcpus_enter_stop(kvm);
}
if (tdx_is_sept_zap_err_due_to_premap(kvm_tdx, err, entry, level) &&
!KVM_BUG_ON(!atomic64_read(&kvm_tdx->nr_premapped), kvm)) {
if (tdx_is_sept_zap_err_due_to_premap(kvm_tdx, err, entry, level)) {
if (KVM_BUG_ON(!atomic64_read(&kvm_tdx->nr_premapped), kvm))
return -EIO;
atomic64_dec(&kvm_tdx->nr_premapped);
return 0;
}