linux-stable/arch/arm64
Mark Rutland bd00cd5f8c arm64: place initial page tables above the kernel
Currently we place swapper_pg_dir and idmap_pg_dir below the kernel
image, between PHYS_OFFSET and (PHYS_OFFSET + TEXT_OFFSET). However,
bootloaders may use portions of this memory below the kernel and we do
not parse the memory reservation list until after the MMU has been
enabled. As such we may clobber some memory a bootloader wishes to have
preserved.

To enable the use of all of this memory by bootloaders (when the
required memory reservations are communicated to the kernel) it is
necessary to move our initial page tables elsewhere. As we currently
have an effectively unbound requirement for memory at the end of the
kernel image for .bss, we can place the page tables here.

This patch moves the initial page table to the end of the kernel image,
after the BSS. As they do not consist of any initialised data they will
be stripped from the kernel Image as with the BSS. The BSS clearing
routine is updated to stop at __bss_stop rather than _end so as to not
clobber the page tables, and memory reservations made redundant by the
new organisation are removed.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-07-10 12:36:12 +01:00
..
boot arm64: dts: Add more serial port nodes in APM X-Gene device tree 2014-06-18 12:41:55 +01:00
configs arm64: defconfig update for LTP 2014-06-18 12:40:52 +01:00
crypto arm64/crypto: improve performance of GHASH algorithm 2014-06-18 12:40:54 +01:00
include arm64: place initial page tables above the kernel 2014-07-10 12:36:12 +01:00
kernel arm64: place initial page tables above the kernel 2014-07-10 12:36:12 +01:00
kvm - Optimised assembly string/memory routines (based on the AArch64 Cortex 2014-06-06 10:43:28 -07:00
lib arm64: lib: Implement optimized string length routines 2014-05-23 15:17:12 +01:00
mm arm64: place initial page tables above the kernel 2014-07-10 12:36:12 +01:00
xen arm: xen: implement multicall hypercall support. 2014-04-24 13:09:46 +01:00
Kconfig arm64: Add audit support 2014-07-10 11:06:00 +01:00
Kconfig.debug arm64: remove arch specific earlyprintk 2014-04-24 16:32:27 -07:00
Makefile arm64/crypto: SHA-1 using ARMv8 Crypto Extensions 2014-05-14 10:03:17 -07:00