Matthew Garrett f8b8404337 Modify UEFI anti-bricking code ... This patch reworks the UEFI anti-bricking code, including an effective reversion of cc5a080c and 31ff2f20. It turns out that calling QueryVariableInfo() from boot services results in some firmware implementations jumping to physical addresses even after entering virtual mode, so until we have 1:1 mappings for UEFI runtime space this isn't going to work so well. Reverting these gets us back to the situation where we'd refuse to create variables on some systems because they classify deleted variables as "used" until the firmware triggers a garbage collection run, which they won't do until they reach a lower threshold. This results in it being impossible to install a bootloader, which is unhelpful. Feedback from Samsung indicates that the firmware doesn't need more than 5KB of storage space for its own purposes, so that seems like a reasonable threshold. However, there's still no guarantee that a platform will attempt garbage collection merely because it drops below this threshold. It seems that this is often only triggered if an attempt to write generates a genuine EFI_OUT_OF_RESOURCES error. We can force that by attempting to create a variable larger than the remaining space. This should fail, but if it somehow succeeds we can then immediately delete it. I've tested this on the UEFI machines I have available, but I don't have a Samsung and so can't verify that it avoids the bricking problem. Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com> Signed-off-by: Lee, Chun-Y <jlee@suse.com> [ dummy variable cleanup ] Cc: <stable@vger.kernel.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>		2013-06-10 21:59:37 +01:00
..
a.out.h
auxvec.h
bitsperlong.h
boot.h
bootparam.h	Modify UEFI anti-bricking code	2013-06-10 21:59:37 +01:00
byteorder.h
debugreg.h
e820.h
errno.h
fcntl.h
hw_breakpoint.h	create non-empty arch/x86/include/uapi/asm/ files	2012-12-17 17:15:11 -08:00
hyperv.h
ioctl.h
ioctls.h
ipcbuf.h
ist.h
Kbuild
kvm_para.h
kvm.h	kvm: Allow build-time configuration of KVM device assignment	2013-04-28 12:58:56 +03:00
ldt.h
mce.h	x86, MCE: Retract most UAPI exports	2013-01-09 14:49:02 +01:00
mman.h
msgbuf.h
msr-index.h	Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux	2013-05-11 15:23:17 -07:00
msr.h
mtrr.h
param.h
perf_regs.h
poll.h
posix_types_32.h
posix_types_64.h
posix_types_x32.h
posix_types.h
prctl.h
processor-flags.h
ptrace-abi.h
ptrace.h
resource.h
sembuf.h
setup.h	create non-empty arch/x86/include/uapi/asm/ files	2012-12-17 17:15:11 -08:00
shmbuf.h
sigcontext32.h
sigcontext.h
siginfo.h
signal.h	consolidate kernel-side struct sigaction declarations	2013-02-03 15:09:22 -05:00
socket.h
sockios.h
stat.h
statfs.h
svm.h
swab.h
termbits.h
termios.h
types.h
ucontext.h
unistd.h
vm86.h
vmx.h	KVM: nVMX: Add preemption timer support	2013-03-14 10:01:21 +02:00
vsyscall.h