[PATCH] x86/tdx: Explicitly include <linux/errno.h> in <asm/tdx.h>

[PATCH] x86/tdx: Explicitly include <linux/errno.h> in <asm/tdx.h>

[Kai Huang]

Currently, in <asm/tdx.h> tdx_kvm_hypercall() simply returns -ENODEV
when TDX guest isn't enabled in the Kconfig w/o having <linux/errno.h>
header explicitly included.  Although the current code doesn't have
build error, in general it is a good practice to explicitly include the
header to make sure any future patch which uses <asm/tdx.h> won't get
build error due to error code not being defined.

Fixes: cfb8ec7a31f2 ("x86/tdx: Wire up KVM hypercalls")
Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Kai Huang <kai.huang@intel.com>
---
 arch/x86/include/asm/tdx.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 28d889c9aa16..0f303c9abee8 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -5,6 +5,7 @@
 
 #include <linux/init.h>
 #include <linux/bits.h>
+#include <linux/errno.h>
 #include <asm/ptrace.h>
 #include <asm/shared/tdx.h>
 

base-commit: 122333d6bd229af279cdb35d1b874b71b3b9ccfb
-- 
2.40.1

Re: [PATCH] x86/tdx: Explicitly include <linux/errno.h> in <asm/tdx.h>

[Kirill A. Shutemov]

On Tue, Jun 06, 2023 at 03:40:00PM +1200, Kai Huang wrote:
> Currently, in <asm/tdx.h> tdx_kvm_hypercall() simply returns -ENODEV
> when TDX guest isn't enabled in the Kconfig w/o having <linux/errno.h>
> header explicitly included.  Although the current code doesn't have
> build error, in general it is a good practice to explicitly include the
> header to make sure any future patch which uses <asm/tdx.h> won't get
> build error due to error code not being defined.
> 
> Fixes: cfb8ec7a31f2 ("x86/tdx: Wire up KVM hypercalls")
> Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
> Cc: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Cc: Dave Hansen <dave.hansen@linux.intel.com>
> Cc: Isaku Yamahata <isaku.yamahata@intel.com>
> Signed-off-by: Kai Huang <kai.huang@intel.com>

Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>

-- 
  Kiryl Shutsemau / Kirill A. Shutemov

Re: [PATCH] x86/tdx: Explicitly include <linux/errno.h> in <asm/tdx.h>

[Sathyanarayanan Kuppuswamy]

On 6/5/23 8:40 PM, Kai Huang wrote:
> Currently, in <asm/tdx.h> tdx_kvm_hypercall() simply returns -ENODEV
> when TDX guest isn't enabled in the Kconfig w/o having <linux/errno.h>

Maybe you can explicitly say "CONFIG_INTEL_TDX_GUEST is not enabled"


> header explicitly included.  Although the current code doesn't have
> build error, in general it is a good practice to explicitly include the
> header to make sure any future patch which uses <asm/tdx.h> won't get
> build error due to error code not being defined.

Otherwise, it looks fine.

Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>

> 
> Fixes: cfb8ec7a31f2 ("x86/tdx: Wire up KVM hypercalls")
> Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
> Cc: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Cc: Dave Hansen <dave.hansen@linux.intel.com>
> Cc: Isaku Yamahata <isaku.yamahata@intel.com>
> Signed-off-by: Kai Huang <kai.huang@intel.com>
> ---
>  arch/x86/include/asm/tdx.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
> index 28d889c9aa16..0f303c9abee8 100644
> --- a/arch/x86/include/asm/tdx.h
> +++ b/arch/x86/include/asm/tdx.h
> @@ -5,6 +5,7 @@
>  
>  #include <linux/init.h>
>  #include <linux/bits.h>
> +#include <linux/errno.h>
>  #include <asm/ptrace.h>
>  #include <asm/shared/tdx.h>
>  
> 
> base-commit: 122333d6bd229af279cdb35d1b874b71b3b9ccfb

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer

Re: [PATCH] x86/tdx: Explicitly include <linux/errno.h> in <asm/tdx.h>

[Huang, Kai]

On Tue, 2023-06-06 at 06:10 -0700, Sathyanarayanan Kuppuswamy wrote:
> 
> On 6/5/23 8:40 PM, Kai Huang wrote:
> > Currently, in <asm/tdx.h> tdx_kvm_hypercall() simply returns -ENODEV
> > when TDX guest isn't enabled in the Kconfig w/o having <linux/errno.h>
> 
> Maybe you can explicitly say "CONFIG_INTEL_TDX_GUEST is not enabled"

It also can be disabled by !CONFIG_KVM_GUEST.

Re: [PATCH] x86/tdx: Explicitly include <linux/errno.h> in <asm/tdx.h>

[Kirill A. Shutemov]

On Tue, Jun 06, 2023 at 10:17:53PM +0000, Huang, Kai wrote:
> On Tue, 2023-06-06 at 06:10 -0700, Sathyanarayanan Kuppuswamy wrote:
> > 
> > On 6/5/23 8:40 PM, Kai Huang wrote:
> > > Currently, in <asm/tdx.h> tdx_kvm_hypercall() simply returns -ENODEV
> > > when TDX guest isn't enabled in the Kconfig w/o having <linux/errno.h>
> > 
> > Maybe you can explicitly say "CONFIG_INTEL_TDX_GUEST is not enabled"
> 
> It also can be disabled by !CONFIG_KVM_GUEST.

Borislav has already fixed it during unaccepted memory patchset
application. He used <asm/errno.h>, not <linux/errno.h>.

See [1] and [2].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=75d090fd167acab4d7eda7e2b65729e877c0fd64
[2] https://lore.kernel.org/all/20230606161606.GDZH9bxhrGnFkaLl2A@fat_crate.local

-- 
  Kiryl Shutsemau / Kirill A. Shutemov

Re: [PATCH] x86/tdx: Explicitly include <linux/errno.h> in <asm/tdx.h>

[Huang, Kai]

On Wed, 2023-06-07 at 01:45 +0300, Kirill A. Shutemov wrote:
> On Tue, Jun 06, 2023 at 10:17:53PM +0000, Huang, Kai wrote:
> > On Tue, 2023-06-06 at 06:10 -0700, Sathyanarayanan Kuppuswamy wrote:
> > > 
> > > On 6/5/23 8:40 PM, Kai Huang wrote:
> > > > Currently, in <asm/tdx.h> tdx_kvm_hypercall() simply returns -ENODEV
> > > > when TDX guest isn't enabled in the Kconfig w/o having <linux/errno.h>
> > > 
> > > Maybe you can explicitly say "CONFIG_INTEL_TDX_GUEST is not enabled"
> > 
> > It also can be disabled by !CONFIG_KVM_GUEST.
> 
> Borislav has already fixed it during unaccepted memory patchset
> application. He used <asm/errno.h>, not <linux/errno.h>.
> 
> See [1] and [2].
> 
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=75d090fd167acab4d7eda7e2b65729e877c0fd64
> [2] https://lore.kernel.org/all/20230606161606.GDZH9bxhrGnFkaLl2A@fat_crate.local
> 

Wonderful, then we can drop this one :)