[edk2-devel] [PATCH v2 1/1] ArmPkg: Fix uninitialised variable in ArmMmuStandaloneMmLib

[Sughosh Ganu]

On Thu, 25 Feb 2021 at 22:41, Sami Mujawar <sami.mujawar at arm.com> wrote:

> The following patches added support for StandaloneMM using FF-A:
> 9da5ee116a28 ArmPkg: Allow FF-A calls to set memory region's attributes
> 0e43e02b9bd8 ArmPkg: Allow FF-A calls to get memory region's attributes
>
> However, in the error handling logic for the Get/Set Memory attributes,
> the CLANG compiler reports that a status variable could be used without
> initialisation. This issue is a false positive and is not seen with GCC.
>
> The Get/Set Memory attributes operation is atomic and therefore an
> FFA_INTERRUPT or FFA_SUCCESS response is not expected in response
> to FFA_MSG_SEND_DIRECT_REQ. So the remaining cases that could occur
> are:
>  - the target sends FFA_MSG_SEND_DIRECT_RESP with a success or
>    failure code.
>  or
>  - FFA_MSG_SEND_DIRECT_REQ transmission failure.
>
> Therefore,
>  - reorder the error handling conditions such that it prevents the
>    uninitialised variable issue being flagged by CLANG.
>  - move the repetitive code to a static helper function and add
>    documentation at the appropriate places.
>  - fix error handling in functions that invoke GetMemoryPermissions().
>
> Signed-off-by: Sami Mujawar <sami.mujawar at arm.com>
> ---
> The changes can be seen at:
> https://github.com/samimujawar/edk2/tree/1657_stmm_ffa_fix_unused_var_v2


 Tested the changes on the StandaloneMm image on the Qemu platform.

Tested-by: Sughosh Ganu <sughosh.ganu at linaro.org>
Reviewed-by: Sughosh Ganu <sughosh.ganu at linaro.org>

-sughosh


-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#72230): https://edk2.groups.io/g/devel/message/72230
Mute This Topic: https://groups.io/mt/80906907/1813853
Group Owner: devel+owner at edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [edk2-devel-archive at redhat.com]
-=-=-=-=-=-=-=-=-=-=-=-


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/edk2-devel-archive/attachments/20210226/6f338261/attachment.htm>