Re: [v2][PATCH 1/2] x86/virt/tdx: Remove __user annotation from kernel pointer

[Kiryl Shutsemau]

On Mon, Nov 03, 2025 at 03:44:37PM -0800, Dave Hansen wrote:
> 
> From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> 
> Separate __user pointer variable declaration from kernel one.
> 
> There are two 'kvm_cpuid2' pointers involved here. There's an "input"
> side: 'td_cpuid' which is a normal kernel pointer and an 'output'
> side. The output here is userspace and there is an attempt at properly
> annotating the variable with __user:
> 
> 	struct kvm_cpuid2 __user *output, *td_cpuid;
> 
> But, alas, this is wrong. The __user in the definition applies to both
> 'output' and 'td_cpuid'. Sparse notices the address space mismatch and
> will complain about it.
> 
> Fix it up by completely separating the two definitions so that it is
> obviously correct without even having to know what the C syntax rules
> even are.
> 
> Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> Fixes: 488808e682e7 ("KVM: x86: Introduce KVM_TDX_GET_CPUID")
> Reviewed-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
> Cc: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
> Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> Cc: Borislav Petkov <bp@xxxxxxxxx>
> Cc: x86@xxxxxxxxxx
> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
> Cc: "Kirill A. Shutemov" <kas@xxxxxxxxxx>
> Cc: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
> Cc: kvm@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx

Acked-by: Kiryl Shutsemau <kas@xxxxxxxxxx>

-- 
 Kiryl Shutsemau / Kirill A. Shutemov