Re: [PATCH 1/2] x86, KVM:SVM: Move sev specific parsing into arch/x86/virt/svm

["Paluri, PavanKumar" <papaluri@amd.com>]

Hi Boris,

On 8/29/2024 8:24 AM, Borislav Petkov wrote:
> On Thu, Aug 01, 2024 at 03:56:37PM -0500, Pavan Kumar Paluri wrote:
>> +#include <linux/memblock.h>
> 
> What's the idea of adding some random include here?
> 
> Does this file use memblock?
> 
> I don't think so.
> 
> You need to resolve include visibility by including the headers where you need
> them:
> 

Understood, will include *only* those headers that provide me with the
facilities as you mentioned.

> diff --git a/arch/x86/include/asm/sev-common.h b/arch/x86/include/asm/sev-common.h
> index dd302fe49f04..d3e7f97e2a4a 100644
> --- a/arch/x86/include/asm/sev-common.h
> +++ b/arch/x86/include/asm/sev-common.h
> @@ -8,6 +8,9 @@
>  #ifndef __ASM_X86_SEV_COMMON_H
>  #define __ASM_X86_SEV_COMMON_H
>  
> +#include <asm/cache.h>
> +#include <asm/pgtable_types.h>
> +
>  #define GHCB_MSR_INFO_POS		0
>  #define GHCB_DATA_LOW			12
>  #define GHCB_MSR_INFO_MASK		(BIT_ULL(GHCB_DATA_LOW) - 1)
> diff --git a/arch/x86/virt/svm/cmdline.c b/arch/x86/virt/svm/cmdline.c
> index 507549a9c793..f0a532108f49 100644
> --- a/arch/x86/virt/svm/cmdline.c
> +++ b/arch/x86/virt/svm/cmdline.c
> @@ -5,11 +5,8 @@
>   * Copyright (C) 2023 - 2024 Advanced Micro Devices, Inc.
>   *
>   * Author: Michael Roth <michael.roth@amd.com>
> - *
>   */
>  
> -#include <linux/memblock.h>
> -
>  #include <asm/sev.h>
>  
>  struct sev_config sev_cfg;
> 

With the above diff applied, I was observing the following compilation
errors relating to string header:

arch/x86/virt/svm/cmdline.c: In function ‘init_sev_config’:
arch/x86/virt/svm/cmdline.c:20:21: error: implicit declaration of
function ‘strsep’ [-Werror=implicit-function-declaration]
   20 |         while ((s = strsep(&str, ","))) {
      |                     ^~~~~~
arch/x86/virt/svm/cmdline.c:20:19: warning: assignment to ‘char *’ from
‘int’ makes pointer from integer without a cast [-Wint-conversion]
   20 |         while ((s = strsep(&str, ","))) {
      |                   ^
arch/x86/virt/svm/cmdline.c:21:22: error: implicit declaration of
function ‘strcmp’ [-Werror=implicit-function-declaration]
   21 |                 if (!strcmp(s, "debug")) {
      |                      ^~~~~~
arch/x86/virt/svm/cmdline.c:13:1: note: include ‘<string.h>’ or provide
a declaration of ‘strcmp’
   12 | #include <asm/sev.h>
  +++ |+#include <string.h>
   13 |
arch/x86/virt/svm/cmdline.c:26:17: error: implicit declaration of
function ‘pr_info’ [-Werror=implicit-function-declaration]
   26 |                 pr_info("SEV command-line option '%s' was not
recognized\n", s);
      |                 ^~~~~~~

So here's the updated diff (for patch #1) that is compile-tested:

diff --git a/arch/x86/include/asm/sev-common.h
b/arch/x86/include/asm/sev-common.h
index dd302fe49f04..d3e7f97e2a4a 100644
--- a/arch/x86/include/asm/sev-common.h
+++ b/arch/x86/include/asm/sev-common.h
@@ -8,6 +8,9 @@
 #ifndef __ASM_X86_SEV_COMMON_H
 #define __ASM_X86_SEV_COMMON_H

+#include <asm/cache.h>
+#include <asm/pgtable_types.h>
+
 #define GHCB_MSR_INFO_POS              0
 #define GHCB_DATA_LOW                  12
 #define GHCB_MSR_INFO_MASK             (BIT_ULL(GHCB_DATA_LOW) - 1)
diff --git a/arch/x86/virt/svm/cmdline.c b/arch/x86/virt/svm/cmdline.c
index 507549a9c793..be3504a601c0 100644
--- a/arch/x86/virt/svm/cmdline.c
+++ b/arch/x86/virt/svm/cmdline.c
@@ -5,10 +5,9 @@
  * Copyright (C) 2023 - 2024 Advanced Micro Devices, Inc.
  *
  * Author: Michael Roth <michael.roth@amd.com>
- *
  */

-#include <linux/memblock.h>
+#include <linux/string.h>

 #include <asm/sev.h>


And for Patch #2, here's the diff:

diff --git a/arch/x86/virt/svm/cmdline.c b/arch/x86/virt/svm/cmdline.c
index 9cec2c2fb67c..5880df8027e6 100644
--- a/arch/x86/virt/svm/cmdline.c
+++ b/arch/x86/virt/svm/cmdline.c
@@ -8,6 +8,7 @@
  */

 #include <linux/string.h>
+#include <asm/cpufeature.h>

 #include <asm/sev.h>

If these changes look good to you, I will send a v2 incorporating the
changes.

Thanks for the review,
Pavan