FreeBSD-current, panic on UEFI boot after recent changes

[Subbsd]

Hi,

( I apologize if this is a duplicate - first I wrote this as reply-all
on https://lists.freebsd.org/pipermail/freebsd-current/2017-March/064971.html
thread )

After recent changes and fixes (
https://lists.freebsd.org/pipermail/freebsd-current/2017-March/065093.html
) I still had problems on host with increased EFI_STAGING_SIZE value.
I have custom FreeBSD distribution which has a sufficiently large
mfsroot which is loaded through UEFI mode.

To solve the problem, it was suggested to increase this variable and
rebuild /sys/boot:

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=209944

Also, it has to be increased periodically for some reason:

https://svnweb.freebsd.org/base/stable/11/sys/boot/efi/loader/copy.c?r1=305779&r2=305778&pathrev=305779

I've try to ask why than threatens to increase this parameter at once
large (or make it dependent on RAM):
https://lists.freebsd.org/pipermail/freebsd-hackers/2016-November/050142.html
but there are no answer options.

At the moment, on r315141 boot via UEFI is fine with default
EFI_STAGING_SIZE (64)

With EFI_STAGING_SIZE=768 i got panic after recent changes with follow message:

failed to allocate staging area:9
failed to allocate stating area
Failed to start image provided by ZFS (5)

http://pasteboard.co/IvbhU9Ffu.jpg

I believe that there mfsroot may be greater than 64MB soon or later.

Also there are no problems with loading big mfsroot images when MBR
method is used.

PS:  I have ZFS-on-root system. With EFI_STAGING_SIZE=768 I lived with
constant CURRENT svnup/rebuilds for about a year. So I will be glad if
you pay attention to this.

PPS: How to reproduce:

1) EFI_STAGING_SIZE=768 in /etc/make.conf
2) make -C /sys/boot clean
3) make -C /sys/boot
4) make -C /sys/boot install
5) reboot

Thanks!