[PATCH 0/4] Handle memmap and mem kernel options in boot stage kaslr

Baoquan He
2017-04-17T13:35:13Z

People reported kernel panic occurs during system boots up with mem boot option.
After checking code, several problems are found about memmap= and mem= in boot stage
kaslr.

*) In commit f28442497b5c ("x86/boot: Fix KASLR and memmap= collision"), only one memmap
entry is considered and only the last one if multiple memmap entries are specified.

*) mem= and memmap=nn[KMG] are not considered yet. They are used to limit max address
of system. Kernel can't be randomized to be above the limit.

*) kernel-parameters.txt doesn't tell the updated behaviour of memmap=.

This patchset tries to solve above issues.

Baoquan He (4):
param: Move function next_arg to lib/cmdline.c for later reuse
KASLR: Parse all memmap entries in cmdline
KASLR: Handle memory limit specified by memmap and mem option
doc: Update description about memmap option in kernel-parameter.txt

Documentation/admin-guide/kernel-parameters.txt | 9 ++
arch/x86/boot/compressed/cmdline.c | 2 +-
arch/x86/boot/compressed/kaslr.c | 161 ++++++++++++++----------
arch/x86/boot/string.c | 8 ++
include/linux/kernel.h | 1 +
kernel/params.c | 52 --------
lib/cmdline.c | 57 +++++++++
7 files changed, 172 insertions(+), 118 deletions(-)

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2.5.5