[edk2-devel] [PATCH v2 2/2] MdeModulePkg/Bus/Pci/PciHostBridgeDxe: Fix MISSING_BREAK Coverity issue

Ranbir Singh posted 2 patches 2 years, 3 months ago
There is a newer version of this series
[edk2-devel] [PATCH v2 2/2] MdeModulePkg/Bus/Pci/PciHostBridgeDxe: Fix MISSING_BREAK Coverity issue
Posted by Ranbir Singh 2 years, 3 months ago
From: Ranbir Singh <Ranbir.Singh3@Dell.com>

The function SubmitResources has a switch-case code in which the
case ACPI_ADDRESS_SPACE_TYPE_MEM: which falls through to
case ACPI_ADDRESS_SPACE_TYPE_IO: if there is no scenario of
return EFI_INVALID_PARAMETER;

While this may be intentional, it is not evident to any general code
reader why there is no break; in between. Adding

    // No break; here as this is an intentional fallthrough.

as comment in between makes it explicit. Incidentally, the comment
satisfies Coverity as well.

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4212

Cc: Ray Ni <ray.ni@intel.com>
Co-authored-by: Veeresh Sangolli <veeresh.sangolli@dellteam.com>
Signed-off-by: Ranbir Singh <Ranbir.Singh3@Dell.com>
Signed-off-by: Ranbir Singh <rsingh@ventanamicro.com>
---
 MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
index 519e1369f85e..3bd91e2787fd 100644
--- a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
+++ b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
@@ -1531,6 +1531,10 @@ SubmitResources (
               return EFI_INVALID_PARAMETER;
             }
 
+            //
+            // No break; here as this is an intentional fall through.
+            //
+
           case ACPI_ADDRESS_SPACE_TYPE_IO:
             //
             // Check aligment, it should be of the form 2^n-1
-- 
2.34.1



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Re: [edk2-devel] [PATCH v2 2/2] MdeModulePkg/Bus/Pci/PciHostBridgeDxe: Fix MISSING_BREAK Coverity issue
Posted by Laszlo Ersek 2 years, 3 months ago
On 11/7/23 06:06, Ranbir Singh wrote:
> From: Ranbir Singh <Ranbir.Singh3@Dell.com>
> 
> The function SubmitResources has a switch-case code in which the
> case ACPI_ADDRESS_SPACE_TYPE_MEM: which falls through to
> case ACPI_ADDRESS_SPACE_TYPE_IO: if there is no scenario of
> return EFI_INVALID_PARAMETER;
> 
> While this may be intentional, it is not evident to any general code
> reader why there is no break; in between. Adding
> 
>     // No break; here as this is an intentional fallthrough.
> 
> as comment in between makes it explicit. Incidentally, the comment
> satisfies Coverity as well.
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4212
> 
> Cc: Ray Ni <ray.ni@intel.com>
> Co-authored-by: Veeresh Sangolli <veeresh.sangolli@dellteam.com>
> Signed-off-by: Ranbir Singh <Ranbir.Singh3@Dell.com>
> Signed-off-by: Ranbir Singh <rsingh@ventanamicro.com>
> ---
>  MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
> index 519e1369f85e..3bd91e2787fd 100644
> --- a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
> +++ b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridge.c
> @@ -1531,6 +1531,10 @@ SubmitResources (
>                return EFI_INVALID_PARAMETER;
>              }
>  
> +            //
> +            // No break; here as this is an intentional fall through.
> +            //
> +
>            case ACPI_ADDRESS_SPACE_TYPE_IO:
>              //
>              // Check aligment, it should be of the form 2^n-1

I agree with adding the comment (I agree it's a fallthrough), but the
semicolon is weird. I think we should say:

  No break here, as this is an intentional fall through.

Laszlo



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