Matthew Garrett, one of the authors of Linux kernel, conducted a study of Samsung notebooks that met a problem with UEFI-firmware. Security expert published results stating that firmware got blocked only when the UEFI variable store became 50% full. That, in turn, caused to the malfunction of the device.
Garrett said that the problem was discovered only in Samsung 300E5C, NP700Z5C, NP700Z7C, and 530U3C notebooks. He also stated that the block occurred when downloading Linux, using UEFI.
The researcher found a solution: users have to execute “mount -t pstore /sys/fs/pstore /sys/fs/pstore” command. He recommends removing all unnecessary files and rebooting machine. After that, according to Matthew, the machine should work normally.
“UEFI implementations generally handle variable deletion by flagging the space as reclaimable rather than immediately making it available again. You need to reboot in order for the firmware to garbage collect it. Some firmware seems to require two reboot cycles to do this properly”, stated Garrett.
Security expert also created a patch for the bug. You may find it here.
