On 29 January 2018 at 08:55, Huangming (Mark) <[email protected]> wrote: > > > On 2018/1/27 18:37, Ard Biesheuvel wrote: >> On 27 January 2018 at 01:47, Huangming (Mark) <[email protected]> wrote: >>> >>> >>> On 2018/1/23 18:23, Leif Lindholm wrote: >>>> On Thu, Jan 18, 2018 at 11:01:42PM +0800, Ming Huang wrote: >>>>> OsBootLib can create OS option after upgrade firmware. >>>> >>>> I will respond more strongly that Ard did: >>>> >>>> I have seen functionality like this implemented in publicly available >>>> systems - laptops, desktops. >>>> Without exception, they end up in bug reports saying "my system >>>> refuses to boot after installation/upgrade". >>>> Without exception, they add to existing negative perceptions of UEFI >>>> in general in certain market spaces. >>>> >>>> Presumably this is trying to address a real problem you have faced. >>>> Please bring this issue to the table for discussion, so that we can >>>> agree on an appropriate way of resolving it. >>>> >>>> Regardless, this code will not be included in 18.02. >>>> >>>> / >>>> Leif >>>> >>>> . >>>> >>> >>> The problem is that OS boot option is lost after upgrade firmware. >> >> Why is that? There is no need to clear the variable store if you >> upgrade the executable image. If you fix this issue, you don't need >> this patch. >> > > Ok, retaining the variable store can solve the problem also. > But retaining the variable store have some issues, like,if the struct stored > in > variable is different between new firmware and old firmware, this situation > may cause > a problem. >
Yes. That means you have to design it with forward compatibility in mind, i.e., add reserved fields that default to zero, and use zero as a reasonable default when you add new fields. > If OsBootLib is not needed for community, It will use for internal project in > hisilicon. > Well, that is up to you to decide. But I highly recommend not hardcoding this kind of knowledge into the firmware to begin with. > >>> It is inconvenient for using. OsBootLib can help this. >>> >>> OsBootLib retain the options installed by OS, and create OS boot option >>> after upgrade firmware if grub file is existed in EFI partition and in >>> mUefiOsBootFiles, >>> and delete redundant options in the same GPT. >>> >> >> . >> > > -- > Best Regards, > > Ming > _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
