All of lore.kernel.org
 help / color / mirror / Atom feed
From: Nikunj A Dadhania <nikunj@amd.com>
To: <kvm@vger.kernel.org>, <seanjc@google.com>, <pbonzini@redhat.com>
Cc: <thomas.lendacky@amd.com>, <bp@alien8.de>,
	<joao.m.martins@oracle.com>, <nikunj@amd.com>,
	<kai.huang@intel.com>, <yosry@kernel.org>,
	Pankaj Gupta <pankaj.gupta@amd.com>
Subject: [PATCH v8 4/8] KVM: VMX: Use cpu_dirty_log_size instead of enable_pml for PML checks
Date: Mon, 7 Sep 2026 06:39:02 +0000	[thread overview]
Message-ID: <20260907063906.1964557-5-nikunj@amd.com> (raw)
In-Reply-To: <20260907063906.1964557-1-nikunj@amd.com>

Replace the enable_pml check with cpu_dirty_log_size in VMX PML code
to determine whether PML is enabled on a per-VM basis. The enable_pml
module parameter is a global setting that doesn't reflect per-VM
capabilities, whereas cpu_dirty_log_size accurately indicates whether
a specific VM has PML enabled.

For example, TDX VMs don't yet support PML. Using cpu_dirty_log_size
ensures the check correctly reflects this, while enable_pml would
incorrectly indicate PML is available.

This also improves consistency with kvm_mmu_update_cpu_dirty_logging(),
which already uses cpu_dirty_log_size to determine PML enablement.

Suggested-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com>
Signed-off-by: Nikunj A Dadhania <nikunj@amd.com>
---
 arch/x86/kvm/vmx/vmx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 8baf570dd456..d944ea9ed273 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -8422,7 +8422,7 @@ void vmx_update_cpu_dirty_logging(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_vmx *vmx = to_vmx(vcpu);
 
-	if (WARN_ON_ONCE(!enable_pml))
+	if (WARN_ON_ONCE(!vcpu->kvm->arch.cpu_dirty_log_size))
 		return;
 
 	guard(vmx_vmcs01)(vcpu);
-- 
2.48.1


  parent reply	other threads:[~2026-09-07  6:39 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-09-07  6:38 [PATCH v8 0/8] KVM: SVM: Add Page Modification Logging (PML) support Nikunj A Dadhania
2026-09-07  6:38 ` [PATCH v8 1/8] KVM: VMX: Pass @vcpu, not @vmx to init_vmcs() Nikunj A Dadhania
2026-09-07  6:39 ` [PATCH v8 2/8] KVM: x86: Move PML page to common vcpu arch structure Nikunj A Dadhania
2026-09-07  6:39 ` [PATCH v8 3/8] KVM: x86: Carve out PML flush routine Nikunj A Dadhania
2026-09-07  6:39 ` Nikunj A Dadhania [this message]
2026-09-07  6:39 ` [PATCH v8 5/8] KVM: x86: Carve out common dirty logging update Nikunj A Dadhania
2026-09-07  6:39 ` [PATCH v8 6/8] x86/cpufeatures: Add Page modification logging Nikunj A Dadhania
2026-09-07  6:47   ` sashiko-bot
2026-09-07  9:49     ` Nikunj A. Dadhania
2026-09-07  6:39 ` [PATCH v8 7/8] KVM: SVM: Use BIT_ULL for 64-bit misc_ctl bit definitions Nikunj A Dadhania
2026-09-07  6:39 ` [PATCH v8 8/8] KVM: SVM: Add Page modification logging support Nikunj A Dadhania
2026-09-07  7:00   ` sashiko-bot
2026-09-08  4:08     ` Nikunj A. Dadhania
2026-09-10  0:22       ` Sean Christopherson

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=20260907063906.1964557-5-nikunj@amd.com \
    --to=nikunj@amd.com \
    --cc=bp@alien8.de \
    --cc=joao.m.martins@oracle.com \
    --cc=kai.huang@intel.com \
    --cc=kvm@vger.kernel.org \
    --cc=pankaj.gupta@amd.com \
    --cc=pbonzini@redhat.com \
    --cc=seanjc@google.com \
    --cc=thomas.lendacky@amd.com \
    --cc=yosry@kernel.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.