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? > > Is that the only patch which needs to be tested? Ontop of which tree?
That should be the only one on top of plain 4.8-rc1. If it doesn't help, we need more work to do. :-) > CONFIG_RANDOMIZE_MEMORY blew up s2d on my laptop here so I'll run it > once I have the required info from you :) Thanks! Best, Rafael