Kernel Log: Coming in 3.10 (Part 3)
For Linux 3.10, the kernel developers have modified code designed to protect Samsung laptops from faults caused by a problem with garbage collection in the UEFI firmware. The changes mean that the previously sometimes over-eager protection feature, which had occasionally blocked machines from other manufacturers from setting or modifying UEFI variables, will swing into action less frequently. A recent test by c't magazine, for example, found that several test machines were missing UEFI entries for booting the installed Linux OS following UEFI Linux installation, due to UEFI entry creation having been blocked by this feature. Users can solve situations like this by using efibootmgr on a LiveCD Linux, such as Fedora 18 or Ubuntu 12.10, that doesn't contain the code to protect Samsung notebooks and manually create a UEFI boot entry; obviously this option should not be used with a Samsung device. Details of the approach adopted by the revised protection feature can be found in a blog entry by kernel developer Matthew Garrett.
Linux can now slow the timer interrupt for individual CPU cores, which normally fires 100, 250 or 1000 times per second, to just one interrupt per second.