Hi Baoquan,
On 04/26/2017 06:16 AM, Baoquan He wrote: > 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. I confirmed that mem= works correctly. Tested-by: Yasuaki Ishimatsu <isimatu.yasu...@jp.fujitsu.com> Thanks, Yasuaki Ishimatsu > > *) kernel-parameters.txt doesn't tell the updated behaviour of memmap=. > > This patchset tries to solve above issues, and it sits on top of > tip:x86/boot branch. > > Changelog > > v2->v3: > No functionality change in this round. > a)Use local static variable insted of global variable > mem_avoid_memmap_index in patch 1/3. > b)Fix a typo in patch 3/3. > > v1->v2: > a)The original patch 1/4 has been put in tip:x86/boot and no update, > so it's not included in this post. > b)Use patch log Ingo reorganized. > c)lib/ctype.c and lib/cmdline.c are needed for kaslr.c, while those > EXPORT_SYMBOL(x) contained caused failure of build on 32-bit allmodconfig: > ...... > ld: -r and -shared may not be used together > scripts/Makefile.build:294: recipe for target > 'arch/x86/boot/compressed/kaslr.o' failed > ...... > Disabling the symbol exporting removes the build failure. > d)Use dynamic allocation to allocate memory to contain copied kernel cmdline > buffer, it's implemented in include/linux/decompress/mm.h. > > > > Baoquan He (3): > KASLR: Parse all memmap entries in cmdline > KASLR: Handle memory limit specified by memmap and mem option > Documentation/kernel-parameters.txt: Update 'memmap=' option > description > > Documentation/admin-guide/kernel-parameters.txt | 9 ++ > arch/x86/boot/compressed/cmdline.c | 2 +- > arch/x86/boot/compressed/kaslr.c | 183 > +++++++++++++++--------- > arch/x86/boot/string.c | 8 ++ > 4 files changed, 136 insertions(+), 66 deletions(-) >