public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Adrian Hunter <adrian.hunter@intel.com>
To: pbonzini@redhat.com, seanjc@google.com
Cc: kvm@vger.kernel.org, rick.p.edgecombe@intel.com,
	kirill.shutemov@linux.intel.com, kai.huang@intel.com,
	reinette.chatre@intel.com, xiaoyao.li@intel.com,
	tony.lindgren@linux.intel.com, binbin.wu@linux.intel.com,
	isaku.yamahata@intel.com, linux-kernel@vger.kernel.org,
	yan.y.zhao@intel.com, chao.gao@intel.com
Subject: [PATCH 2/2] KVM: x86: Do not use kvm_rip_read() unconditionally for KVM_PROFILING
Date: Tue, 15 Apr 2025 13:48:21 +0300	[thread overview]
Message-ID: <20250415104821.247234-3-adrian.hunter@intel.com> (raw)
In-Reply-To: <20250415104821.247234-1-adrian.hunter@intel.com>

Not all VMs allow access to RIP.  Check guest_state_protected before
calling kvm_rip_read().

This avoids, for example, hitting WARN_ON_ONCE in vt_cache_reg() for
TDX VMs.

Fixes: 81bf912b2c15 ("KVM: TDX: Implement TDX vcpu enter/exit path")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 arch/x86/kvm/x86.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 844e81ee1d96..8758f8cba488 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -11130,7 +11130,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 	/*
 	 * Profile KVM exit RIPs:
 	 */
-	if (unlikely(prof_on == KVM_PROFILING)) {
+	if (unlikely(prof_on == KVM_PROFILING &&
+		     !vcpu->arch.guest_state_protected)) {
 		unsigned long rip = kvm_rip_read(vcpu);
 		profile_hit(KVM_PROFILING, (void *)rip);
 	}
-- 
2.43.0


  parent reply	other threads:[~2025-04-15 10:49 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-15 10:48 [PATCH 0/2] KVM: x86: Correct use of kvm_rip_read() Adrian Hunter
2025-04-15 10:48 ` [PATCH 1/2] KVM: x86: Do not use kvm_rip_read() unconditionally in KVM tracepoints Adrian Hunter
2025-04-15 10:48 ` Adrian Hunter [this message]
2025-04-15 11:31 ` [PATCH 0/2] KVM: x86: Correct use of kvm_rip_read() Paolo Bonzini

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20250415104821.247234-3-adrian.hunter@intel.com \
    --to=adrian.hunter@intel.com \
    --cc=binbin.wu@linux.intel.com \
    --cc=chao.gao@intel.com \
    --cc=isaku.yamahata@intel.com \
    --cc=kai.huang@intel.com \
    --cc=kirill.shutemov@linux.intel.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pbonzini@redhat.com \
    --cc=reinette.chatre@intel.com \
    --cc=rick.p.edgecombe@intel.com \
    --cc=seanjc@google.com \
    --cc=tony.lindgren@linux.intel.com \
    --cc=xiaoyao.li@intel.com \
    --cc=yan.y.zhao@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox