Re: [edk2-devel] EFI Timeout variable is ignored (initialized to default on every boot)

["Laszlo Ersek" <lersek@redhat.com>]

Hi,

On 07/11/20 15:12, Andrei Borzenkov wrote:
> Using 202005 version I am not able to change "Boot Maintenance Manager"
> - "Auto Boot Time-out" or set Timeout variable from within Linux with
> efibootmgr - value is overwritten with default (normally 0) on every
> boot. The only possibility is to use -boot menu=on QEMU option. Looking
> at code, PlatformBootManagerBeforeConsole() unconditionally sets Timeout
> to value obtained from GetFrontPageTimeoutFromQemu() which in turn
> returns PcdPlatformBootTimeOut (default 0) if nothing was present on
> command line (or in general passed via fw_cfg).
> 
> I'd expect that default should be current value of Timeout unless
> overridden by command line/fw_cfg. It is OK to initialize it for the
> first time to PcdPlatformBootTimeOut if Timeout was not defined, but
> certainly not every time on every boot.

BdsDxe overwrites the Timeout non-volatile variable with
PcdPlatformBootTimeOut, before calling PlatformBootManagerBeforeConsole().

OvmfPkg platform code does not write to the Timeout non-volatile
variable. OvmfPkg platform code only sets PcdPlatformBootTimeOut (from
fw_cfg), but that happens only after BdsDxe has overwritten Timeout with
PcdPlatformBootTimeOut.

https://bugzilla.tianocore.org/show_bug.cgi?id=2488#c1

Laszlo