[v2][PATCH 2/2] x86/virt/tdx: Fix sparse warnings from using 0 for NULL

Dave Hansen posted 2 patches 1 month, 1 week ago
[v2][PATCH 2/2] x86/virt/tdx: Fix sparse warnings from using 0 for NULL
Posted by Dave Hansen 1 month, 1 week ago

From: Dave Hansen <dave.hansen@linux.intel.com>

Stop using 0 for NULL.

sparse moans:

	... arch/x86/kvm/vmx/tdx.c:859:38: warning: Using plain integer as NULL pointer

for several TDX pointer initializations. While I love a good ptr=0
now and then, it's good to have quiet sparse builds.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Fixes: a50f673f25e0 ("KVM: TDX: Do TDX specific vcpu initialization")
Fixes: 8d032b683c29 ("KVM: TDX: create/destroy VM structure")
Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Xiaoyao Li <xiaoyao.li@intel.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Kirill A. Shutemov" <kas@kernel.org>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---

 b/arch/x86/kvm/vmx/tdx.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff -puN arch/x86/kvm/vmx/tdx.c~tdx-sparse-fix-1 arch/x86/kvm/vmx/tdx.c
--- a/arch/x86/kvm/vmx/tdx.c~tdx-sparse-fix-1	2025-11-03 15:11:28.177643833 -0800
+++ b/arch/x86/kvm/vmx/tdx.c	2025-11-03 15:11:28.185644508 -0800
@@ -856,7 +856,7 @@ void tdx_vcpu_free(struct kvm_vcpu *vcpu
 	}
 	if (tdx->vp.tdvpr_page) {
 		tdx_reclaim_control_page(tdx->vp.tdvpr_page);
-		tdx->vp.tdvpr_page = 0;
+		tdx->vp.tdvpr_page = NULL;
 		tdx->vp.tdvpr_pa = 0;
 	}
 
@@ -2642,7 +2642,7 @@ free_tdcs:
 free_tdr:
 	if (tdr_page)
 		__free_page(tdr_page);
-	kvm_tdx->td.tdr_page = 0;
+	kvm_tdx->td.tdr_page = NULL;
 
 free_hkid:
 	tdx_hkid_free(kvm_tdx);
@@ -3016,7 +3016,7 @@ free_tdcx:
 free_tdvpr:
 	if (tdx->vp.tdvpr_page)
 		__free_page(tdx->vp.tdvpr_page);
-	tdx->vp.tdvpr_page = 0;
+	tdx->vp.tdvpr_page = NULL;
 	tdx->vp.tdvpr_pa = 0;
 
 	return ret;
_
Re: [v2][PATCH 2/2] x86/virt/tdx: Fix sparse warnings from using 0 for NULL
Posted by Xiaoyao Li 1 month, 1 week ago
On 11/4/2025 7:44 AM, Dave Hansen wrote:
> 
> From: Dave Hansen <dave.hansen@linux.intel.com>
> 
> Stop using 0 for NULL.
> 
> sparse moans:
> 
> 	... arch/x86/kvm/vmx/tdx.c:859:38: warning: Using plain integer as NULL pointer
> 
> for several TDX pointer initializations. While I love a good ptr=0
> now and then, it's good to have quiet sparse builds.
> 
> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
> Fixes: a50f673f25e0 ("KVM: TDX: Do TDX specific vcpu initialization")
> Fixes: 8d032b683c29 ("KVM: TDX: create/destroy VM structure")
> Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>

Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>

> Cc: Xiaoyao Li <xiaoyao.li@intel.com>
> Cc: Sean Christopherson <seanjc@google.com>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: x86@kernel.org
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: "Kirill A. Shutemov" <kas@kernel.org>
> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
> Cc: kvm@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> ---
> 
>   b/arch/x86/kvm/vmx/tdx.c |    6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff -puN arch/x86/kvm/vmx/tdx.c~tdx-sparse-fix-1 arch/x86/kvm/vmx/tdx.c
> --- a/arch/x86/kvm/vmx/tdx.c~tdx-sparse-fix-1	2025-11-03 15:11:28.177643833 -0800
> +++ b/arch/x86/kvm/vmx/tdx.c	2025-11-03 15:11:28.185644508 -0800
> @@ -856,7 +856,7 @@ void tdx_vcpu_free(struct kvm_vcpu *vcpu
>   	}
>   	if (tdx->vp.tdvpr_page) {
>   		tdx_reclaim_control_page(tdx->vp.tdvpr_page);
> -		tdx->vp.tdvpr_page = 0;
> +		tdx->vp.tdvpr_page = NULL;
>   		tdx->vp.tdvpr_pa = 0;
>   	}
>   
> @@ -2642,7 +2642,7 @@ free_tdcs:
>   free_tdr:
>   	if (tdr_page)
>   		__free_page(tdr_page);
> -	kvm_tdx->td.tdr_page = 0;
> +	kvm_tdx->td.tdr_page = NULL;
>   
>   free_hkid:
>   	tdx_hkid_free(kvm_tdx);
> @@ -3016,7 +3016,7 @@ free_tdcx:
>   free_tdvpr:
>   	if (tdx->vp.tdvpr_page)
>   		__free_page(tdx->vp.tdvpr_page);
> -	tdx->vp.tdvpr_page = 0;
> +	tdx->vp.tdvpr_page = NULL;
>   	tdx->vp.tdvpr_pa = 0;
>   
>   	return ret;
> _
Re: [v2][PATCH 2/2] x86/virt/tdx: Fix sparse warnings from using 0 for NULL
Posted by Kiryl Shutsemau 1 month, 1 week ago
On Mon, Nov 03, 2025 at 03:44:39PM -0800, Dave Hansen wrote:
> 
> From: Dave Hansen <dave.hansen@linux.intel.com>
> 
> Stop using 0 for NULL.
> 
> sparse moans:
> 
> 	... arch/x86/kvm/vmx/tdx.c:859:38: warning: Using plain integer as NULL pointer
> 
> for several TDX pointer initializations. While I love a good ptr=0
> now and then, it's good to have quiet sparse builds.
> 
> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
> Fixes: a50f673f25e0 ("KVM: TDX: Do TDX specific vcpu initialization")
> Fixes: 8d032b683c29 ("KVM: TDX: create/destroy VM structure")
> Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
> Cc: Xiaoyao Li <xiaoyao.li@intel.com>
> Cc: Sean Christopherson <seanjc@google.com>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: x86@kernel.org
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: "Kirill A. Shutemov" <kas@kernel.org>
> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
> Cc: kvm@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org

Acked-by: Kiryl Shutsemau <kas@kernel.org>

-- 
  Kiryl Shutsemau / Kirill A. Shutemov