linux-kernel - [RFC PATCH 06/12] KVM: TDX: Return -EIO, not -EINVAL, on a KVM_BUG

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250827000522.4022426-7-seanjc@google.com>
Date: Tue, 26 Aug 2025 17:05:16 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Sean Christopherson <seanjc@...gle.com>, Paolo Bonzini <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	Michael Roth <michael.roth@....com>, Yan Zhao <yan.y.zhao@...el.com>, 
	Ira Weiny <ira.weiny@...el.com>, Vishal Annapurve <vannapurve@...gle.com>, 
	Rick Edgecombe <rick.p.edgecombe@...el.com>
Subject: [RFC PATCH 06/12] KVM: TDX: Return -EIO, not -EINVAL, on a
 KVM_BUG_ON() condition

Return -EIO when a KVM_BUG_ON() is tripped, as KVM's ABI is to return -EIO
when a VM has been killed due to a KVM bug, not -EINVAL.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/vmx/tdx.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 9fb6e5f02cc9..ef4ffcad131f 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1624,7 +1624,7 @@ static int tdx_mem_page_record_premap_cnt(struct kvm *kvm, gfn_t gfn,
 	struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
 
 	if (KVM_BUG_ON(kvm->arch.pre_fault_allowed, kvm))
-		return -EINVAL;
+		return -EIO;
 
 	/* nr_premapped will be decreased when tdh_mem_page_add() is called. */
 	atomic64_inc(&kvm_tdx->nr_premapped);
@@ -1638,7 +1638,7 @@ static int tdx_sept_set_private_spte(struct kvm *kvm, gfn_t gfn,
 
 	/* TODO: handle large pages. */
 	if (KVM_BUG_ON(level != PG_LEVEL_4K, kvm))
-		return -EINVAL;
+		return -EIO;
 
 	/*
 	 * Read 'pre_fault_allowed' before 'kvm_tdx->state'; see matching
@@ -1849,7 +1849,7 @@ static int tdx_sept_free_private_spt(struct kvm *kvm, gfn_t gfn,
 	 * and slot move/deletion.
 	 */
 	if (KVM_BUG_ON(is_hkid_assigned(kvm_tdx), kvm))
-		return -EINVAL;
+		return -EIO;
 
 	/*
 	 * The HKID assigned to this TD was already freed and cache was
@@ -1870,7 +1870,7 @@ static int tdx_sept_remove_private_spte(struct kvm *kvm, gfn_t gfn,
 	 * there can't be anything populated in the private EPT.
 	 */
 	if (KVM_BUG_ON(!is_hkid_assigned(to_kvm_tdx(kvm)), kvm))
-		return -EINVAL;
+		return -EIO;
 
 	ret = tdx_sept_zap_private_spte(kvm, gfn, level, page);
 	if (ret <= 0)
-- 
2.51.0.268.g9569e192d0-goog