[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <87368su7lb.fsf@dja-thinkpad.axtens.net>
Date: Sat, 25 Apr 2020 03:17:04 +1000
From: Daniel Axtens <dja@...ens.net>
To: Jason Yan <yanaijie@...wei.com>, mpe@...erman.id.au, linuxppc-dev@...ts.ozlabs.org, diana.craciun@....com, christophe.leroy@....fr, benh@...nel.crashing.org, paulus@...ba.org, npiggin@...il.com, keescook@...omium.org, kernel-hardening@...ts.openwall.com, oss@...error.net
Cc: linux-kernel@...r.kernel.org, zhaohongjiang@...wei.com, Jason Yan <yanaijie@...wei.com>
Subject: Re: [PATCH v5 0/6] implement KASLR for powerpc/fsl_booke/64
Hi Jason,
Apologies for the delay in testing.
I'm seeing this problem when I try to boot on a t4240rdb:
random: get_random_u64 called from .start_kernel+0x734/0x964 with crng_init=0 [8/973]
clocksource: timebase: mask: 0xffffffffffffffff max_cycles: 0xa9210e89c, max_idle_ns: 440795203878 ns
clocksource: timebase mult[15d17460] shift[24] registered
Console: colour dummy device 80x25
pid_max: default: 32768 minimum: 301
Mount-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
e6500 family performance monitor hardware support registered
rcu: Hierarchical SRCU implementation.
smp: Bringing up secondary CPUs ...
Processor 2 is stuck.
Processor 3 is stuck.
Processor 4 is stuck.
Processor 5 is stuck.
Processor 6 is stuck.
Processor 7 is stuck.
Processor 8 is stuck.
Processor 9 is stuck.
Processor 10 is stuck.
Processor 11 is stuck.
Processor 12 is stuck.
Processor 13 is stuck.
Processor 14 is stuck.
...
Processor 22 is stuck.
Processor 23 is stuck.
smp: Brought up 1 node, 2 CPUs
Using standard scheduler topology
devtmpfs: initialized
clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
futex hash table entries: 8192 (order: 7, 524288 bytes, linear)
NET: Registered protocol family 16
audit: initializing netlink subsys (disabled)
audit: type=2000 audit(108.032:1): state=initialized audit_enabled=0 res=1
Machine: fsl,T4240RDB
SoC family: QorIQ T4240
SoC ID: svr:0x82480020, Revision: 2.0
... boot continues ...
If I boot with nokaslr, all the CPUs come up with no issue.
This is on top of powerpc/merge at
8299da600ad05b8aa0f15ec0f5f03bd40e37d6f0. If you'd like me to test any
debug patches I can do that.
I've attached my .config.
Regards,
Daniel
Download attachment ".config" of type "application/octet-stream" (94743 bytes)
> 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.
>
> v4->v5:
> Fix "-Werror=maybe-uninitialized" compile error.
> Fix typo "similar as" -> "similar to".
> 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 | 91 +++++++++++++------
> 8 files changed, 147 insertions(+), 45 deletions(-)
> rename Documentation/powerpc/{kaslr-booke32.rst => kaslr-booke.rst} (59%)
>
> --
> 2.17.2
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
