On Mon, Aug 8, 2016 at 8:00 PM, Thomas Garnier <thgar...@google.com> wrote: > On Mon, Aug 8, 2016 at 6:54 AM, Rafael J. Wysocki <raf...@kernel.org> wrote: >> On Mon, Aug 8, 2016 at 3:40 PM, Borislav Petkov <b...@suse.de> wrote: >>> On Mon, Aug 08, 2016 at 03:31:31PM +0200, Rafael J. Wysocki wrote: >>>> From: Rafael J. Wysocki <rafael.j.wyso...@intel.com> >>>> >>>> The low-level resume-from-hibernation code on x86-64 uses >>>> kernel_ident_mapping_init() to create the temoprary identity mapping, >>>> but that function assumes that the offset between kernel virtual >>>> addresses and physical addresses is aligned on the PGD level. >>>> >>>> However, with a randomized identity mapping base, it may be aligned >>>> on the PUD level and if that happens, the temporary identity mapping >>>> created by set_up_temporary_mappings() will not reflect the actual >>>> kernel identity mapping and the image restoration will fail as a >>>> result (leading to a kernel panic most of the time). >>>> >>>> To fix this problem, rework kernel_ident_mapping_init() to support >>>> unaligned offsets between KVA and PA up to the PMD level and make >>>> set_up_temporary_mappings() use it as approprtiate. >>>> >>>> Reported-by: Thomas Garnier <thgar...@google.com> >>> >>> Reported-by: Borislav Petkov <b...@suse.de> >>> >>>> Suggested-by: Yinghai Lu <ying...@kernel.org> >>>> Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com> >>>> Acked-by: Yinghai Lu <ying...@kernel.org> >>>> --- >>>> >>>> This is sort of urgent, because hibernation doesn't work with KASLR on >>>> x86-64 >>>> in 4.8-rc1 AFAICS and this should make them work together again. >>>> >>>> Unless anyone sees any problems with it, I'll queue it up for 4.8-rc2. >>>> >>>> Thomas, would it be possible to test it with KASLR enabled, please? >>> > > I tested it on my setup couple times. Worked well.
Thanks!