[PATCH v2 1/1] OvmfPkg/QemuFwCfgLib: Suppress GCC49 IA32 build failure

[PATCH v2 1/1] OvmfPkg/QemuFwCfgLib: Suppress GCC49 IA32 build failure

[Brijesh Singh]

NumPages variable was introduced in commit 66c548be509d. In this commit
we allocate an intermediate buffer when SEV is enabled. The 'BounceBuffer'
variable points to the intermediate buffer pointer and NumPages variables
stores the number of pages. Later in the code, 'BounceBuffer' variable is
checked to see if we need to free the intermediate buffers. The code looks
correct, suppress the warning.

Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Reported-by: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---
Changes since v1:
 - add comments and move the local variable initialization to new line

 OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
index dbebd36b1853..0310d2872dae 100644
--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
@@ -83,6 +83,11 @@ InternalQemuFwCfgDmaBytes (
   }
 
   //
+  // set NumPages to suppress incorrect compiler/analyzer warnigns
+  //
+  NumPages = 0;
+
+  //
   // When SEV is enabled then allocate DMA bounce buffer
   //
   if (InternalQemuFwCfgSevIsEnabled ()) {
-- 
2.7.4

Re: [PATCH v2 1/1] OvmfPkg/QemuFwCfgLib: Suppress GCC49 IA32 build failure

[Laszlo Ersek]

On 07/11/17 20:38, Brijesh Singh wrote:
> NumPages variable was introduced in commit 66c548be509d. In this commit
> we allocate an intermediate buffer when SEV is enabled. The 'BounceBuffer'
> variable points to the intermediate buffer pointer and NumPages variables
> stores the number of pages. Later in the code, 'BounceBuffer' variable is
> checked to see if we need to free the intermediate buffers. The code looks
> correct, suppress the warning.
> 
> Cc: Jordan Justen <jordan.l.justen@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Reported-by: Laszlo Ersek <lersek@redhat.com>
> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
> ---
> Changes since v1:
>  - add comments and move the local variable initialization to new line
> 
>  OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
> index dbebd36b1853..0310d2872dae 100644
> --- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
> +++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
> @@ -83,6 +83,11 @@ InternalQemuFwCfgDmaBytes (
>    }
>  
>    //
> +  // set NumPages to suppress incorrect compiler/analyzer warnigns
> +  //
> +  NumPages = 0;
> +
> +  //
>    // When SEV is enabled then allocate DMA bounce buffer
>    //
>    if (InternalQemuFwCfgSevIsEnabled ()) {
> 

Reported-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
[lersek@redhat.com: s/warnigns/warnings/ in the code comment]
[lersek@redhat.com: add Gerd's Reported-by]
Signed-off-by: Laszlo Ersek <lersek@redhat.com>

Pushed as commit e508e069a809.

I also fixed up the typo in
<https://bugzilla.tianocore.org/show_bug.cgi?id=607#c3>.

Thanks!
Laszlo