Hi Steve/Colin/CluedInPeople, I have a query related to the FIx. Shouldn't the right fix for this bug if one wants to use secure boot and uefi to boot their system be the noefi boot param related fix added to linux kernels around 15th Feb i.e
commit 1de63d60cd5b0d33a812efa455d5933bf1564a51 upstream. Because if I understand correctly the issue is less to do with the samsung laptop module per se and more to do with the buggy Samsung EFI logic which craps it self out if one writes to the efi storage space sometimes (or is it always - not 100% sure currently). And in turn if linux kernel crashes or catches a mce for some reason or the other (like previously triggered by the samsung laptop module) and is in efi mode, then because it writes the crash log to efi storage space, this serious bug in samsung efi code gets triggered and potentially take the full laptop down with it. And if I get things correctly then passing noefi to linux kernel as a boot param will disable the use of efi runtime services by the kernel and its modules. And that is the 100% sure way of ensuring that under linux one cann't trigger this bug in the normal sense (Still is it 100% safe from a security perspective I am not sure if Samsung efi logic doesn't have any loop holes which allows one to call efi services even if one has already relinquished it - I am talking logically here, because I haven't looked into efi in detail so am making some/many assumptions). So if one wants to dual boot a system with win8 already installed in Secure boot UEFI mode and Linux THEN one should use a distro of linux which is using linux kernels later than Feb 15 with the above mentioned noefi bug fix included and in turn one should boot such a linux distro with noefi boot param to ensure that the Samsung laptops with this efi bug cann't be triggered from Linux during that boot. Is my above understanding correct and in turn does the new LTS live image use this new kernel, if not shouldn't this be the right solution to this EFI bug in Samsung if one doesn't want to disable secureboot/uefi. NOTE: I am not sure the linux kernel handles the transition from efi to no efi runtime mode gracefully if noefi is passed as a argument and the system is already in uefi boot mode. But I am assuming for now that the kernel handles this situation properly as well as that it is required to handle this in a specific manner, which it does. This is my assumption currently because I haven't looked into EFI specs at any level currently. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1040557 Title: UEFI boot live-usb bricks SAMSUNG 530U3C,np700z5c laptop To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-cdimage/+bug/1040557/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
