Emit a DEBUG_ERROR message if there is not enough space left to write/update a variable. This condition is currently not logged appropriately in all cases, given that full variable store can easily render the system unbootable. This new message helps identifying this condition quickly.
Background: We had the case where an OVMF based VM ran out of flash space after a large number of reboots and hardware configuration changes. The MAC address of the NIC was changing a lot over the life time of the VM. The variable store was consumed entirely by networking related non-volatile variables, written for each network card/MAC address present during boot. Almost all of those were obsolete, of course, but the error that presented itself at first was a VM that failed to boot the firmware and ended up in an rather cryptic ASSERT message. The hope is that this new message makes it easier for non-experts to diagnose the situation. The root cause is of course not addressed by this, but it might also be hard to solve. One would have to identify obsolete network/hardware settings somehow, but there is no way to tell if a certain NIC/MAC might come back at a later point or not. Launching OVMF with a full variable store then looks like this (Debug Output): [...] CommonVariableSpace = 0x3FF9C - CommonVariableTotalSize = 0x3FF60 UpdateVariable failed: Out of variable space Select Item: 0xE Select Item: 0x19 RecordVarErrorFlag (0xEF) Timeout:8BE4DF61-93CA-11D2-AA0D-00E098032B8C - 0x00000007 - 0x4E CommonVariableSpace = 0x3FF9C - CommonVariableTotalSize = 0x3FF60 UpdateVariable failed: Out of variable space PlatformBootManagerBeforeConsole: SetVariable(Timeout, 3): Out of Resources RecordVarErrorFlag (0xEF) BootOrder:8BE4DF61-93CA-11D2-AA0D-00E098032B8C - 0x00000007 - 0x52 CommonVariableSpace = 0x3FF9C - CommonVariableTotalSize = 0x3FF60 UpdateVariable failed: Out of variable space ASSERT_EFI_ERROR (Status = Out of Resources) ASSERT OvmfPkg/Library/PlatformBootManagerLib/BdsPlatform.c(361): !(((INTN)(RETURN_STATUS)(Status)) < 0) PR: https://github.com/tianocore/edk2/pull/5435 Changes since v1: - Mention "variable space" instead of "flash space" - Emit DEBUG_ERROR instead of DEBUG_WARN Cc: Liming Gao <gaolim...@byosoft.com.cn> Cc: Michael D Kinney <michael.d.kin...@intel.com> Cc: Zhiguang Liu <zhiguang....@intel.com> Oliver Steffen (1): MdeModulePkg: Warn if out of space when writing variables MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c | 2 ++ 1 file changed, 2 insertions(+) -- 2.44.0 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#118819): https://edk2.groups.io/g/devel/message/118819 Mute This Topic: https://groups.io/mt/106017604/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
