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-and-tested-by: Thomas Garnier <thgarnie@google.com>
Reported-by: Borislav Petkov <bp@suse.de>
Suggested-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
It is simple version for kernel_physical_mapping_init.
it will work to build one page table that will be used later.
Use mapping_info to control
1. alloc_pg_page method
2. if PMD is EXEC,
3. if pgd is with kernel low mapping or ident mapping.
Will use to replace some local versions in kexec, hibernation and etc.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1359058816-7615-8-git-send-email-yinghai@kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Now init_memory_mapping is called two times, later will be called for every
ram ranges.
Could put all related init_mem calling together and out of setup.c.
Actually, it reverts commit 1bbbbe7
x86: Exclude E820_RESERVED regions and memory holes above 4 GB from direct mapping.
will address that later with complete solution include handling hole under 4g.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1353123563-3103-5-git-send-email-yinghai@kernel.org
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Now that zone_sizes_init() is identical on 32-bit and 64-bit,
move the code to arch/x86/mm/init.c and use it for both
architectures.
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Link: http://lkml.kernel.org/r/1320155902-10424-7-git-send-email-penberg@kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
e820_table_{start|end|top}, which are used to buffer page table
allocation during early boot, are now derived from memblock and don't
have much to do with e820. Change the names so that they reflect what
they're used for.
This patch doesn't introduce any behavior change.
-v2: Ingo found that earlier patch "x86: Use early pre-allocated page
table buffer top-down" caused crash on 32bit and needed to be
dropped. This patch was updated to reflect the change.
-tj: Updated commit description.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
