在 2020/3/20 11:19, Daniel Axtens 写道:
Hi Jason,
I tried to compile this series and got the following error:
/home/dja/dev/linux/linux/arch/powerpc/mm/nohash/kaslr_booke.c: In function ‘kaslr_early_init’:
/home/dja/dev/linux/linux/arch/powerpc/mm/nohash/kaslr_booke.c:357:33: error: ‘linear_sz’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
357 | regions.pa_end = memstart_addr + linear_sz;
| ~~~~~~~~~~~~~~^~~~~~~~~~~
/home/dja/dev/linux/linux/arch/powerpc/mm/nohash/kaslr_booke.c:317:21: note: ‘linear_sz’ was declared here
317 | unsigned long ram, linear_sz;
| ^~~~~~~~~
/home/dja/dev/linux/linux/arch/powerpc/mm/nohash/kaslr_booke.c:187:8: error: ‘ram’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
187 | ret = parse_crashkernel(boot_command_line, size, &crash_size,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
188 | &crash_base);
| ~~~~~~~~~~~~
/home/dja/dev/linux/linux/arch/powerpc/mm/nohash/kaslr_booke.c:317:16: note: ‘ram’ was declared here
317 | unsigned long ram, linear_sz;
| ^~~
cc1: all warnings being treated as errors
make[4]: *** [/home/dja/dev/linux/linux/scripts/Makefile.build:268: arch/powerpc/mm/nohash/kaslr_booke.o] Error 1
make[3]: *** [/home/dja/dev/linux/linux/scripts/Makefile.build:505: arch/powerpc/mm/nohash] Error 2
make[2]: *** [/home/dja/dev/linux/linux/scripts/Makefile.build:505: arch/powerpc/mm] Error 2
make[2]: *** Waiting for unfinished jobs....
I have attached my .config file.
Thanks Daniel,
My config had CC_DISABLE_WARN_MAYBE_UNINITIALIZED=y enabled so I missed
this warning. I will fix it.
Thanks again.
Jason
I'm using
powerpc64-linux-gnu-gcc (Ubuntu 9.2.1-9ubuntu1) 9.2.1 20191008
Regards,
Daniel
This is a try to implement KASLR for Freescale BookE64 which is based on
my earlier implementation for Freescale BookE32:
https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=131718&state=*
The implementation for Freescale BookE64 is similar as BookE32. One
difference is that Freescale BookE64 set up a TLB mapping of 1G during
booting. Another difference is that ppc64 needs the kernel to be
64K-aligned. So we can randomize the kernel in this 1G mapping and make
it 64K-aligned. This can save some code to creat another TLB map at
early boot. The disadvantage is that we only have about 1G/64K = 16384
slots to put the kernel in.
KERNELBASE
64K |--> kernel <--|
| | |
+--+--+--+ +--+--+--+--+--+--+--+--+--+ +--+--+
| | | |....| | | | | | | | | |....| | |
+--+--+--+ +--+--+--+--+--+--+--+--+--+ +--+--+
| | 1G
|-----> offset <-----|
kernstart_virt_addr
I'm not sure if the slot numbers is enough or the design has any
defects. If you have some better ideas, I would be happy to hear that.
Thank you all.
v3->v4:
Do not define __kaslr_offset as a fixed symbol. Reference __run_at_load and
__kaslr_offset by symbol instead of magic offsets.
Use IS_ENABLED(CONFIG_PPC32) instead of #ifdef CONFIG_PPC32.
Change kaslr-booke32 to kaslr-booke in index.rst
Switch some instructions to 64-bit.
v2->v3:
Fix build error when KASLR is disabled.
v1->v2:
Add __kaslr_offset for the secondary cpu boot up.
Jason Yan (6):
powerpc/fsl_booke/kaslr: refactor kaslr_legal_offset() and
kaslr_early_init()
powerpc/fsl_booke/64: introduce reloc_kernel_entry() helper
powerpc/fsl_booke/64: implement KASLR for fsl_booke64
powerpc/fsl_booke/64: do not clear the BSS for the second pass
powerpc/fsl_booke/64: clear the original kernel if randomized
powerpc/fsl_booke/kaslr: rename kaslr-booke32.rst to kaslr-booke.rst
and add 64bit part
Documentation/powerpc/index.rst | 2 +-
.../{kaslr-booke32.rst => kaslr-booke.rst} | 35 +++++++-
arch/powerpc/Kconfig | 2 +-
arch/powerpc/kernel/exceptions-64e.S | 23 +++++
arch/powerpc/kernel/head_64.S | 13 +++
arch/powerpc/kernel/setup_64.c | 3 +
arch/powerpc/mm/mmu_decl.h | 23 ++---
arch/powerpc/mm/nohash/kaslr_booke.c | 88 +++++++++++++------
8 files changed, 144 insertions(+), 45 deletions(-)
rename Documentation/powerpc/{kaslr-booke32.rst => kaslr-booke.rst} (59%)
--
2.17.2
