Re: [PATCH v5 0/6] implement KASLR for powerpc/fsl_booke/64

[Daniel Axtens]

Hi Jason,

> Thanks for the test. Can you send me the full log which may contain the 
> system info such as the following:

It's attached.

Regards,
Daniel

Attachment: fail-log
Description: Binary data

>
> -----------------------------------------------------
> phys_mem_size     = 0x200000000
> dcache_bsize      = 0x20
> icache_bsize      = 0x20
> cpu_features      = 0x00000003008003b6
>    possible        = 0x00000003009003b6
>    always          = 0x00000003008003b4
> cpu_user_features = 0xdc008000 0x08000000
> mmu_features      = 0x000a0010
> firmware_features = 0x0000000000000000
> physical_start    = 0x20000000
> -----------------------------------------------------
> barrier-nospec: using isync; sync as speculation barrier
> Zone ranges:
>    DMA      [mem 0x0000000000000000-0x000000007fffffff]
>    Normal   [mem 0x0000000080000000-0x00000001ffffffff]
> Movable zone start for each node
> Early memory node ranges
>    node   0: [mem 0x0000000000000000-0x00000001ffffffff]
> Initmem setup node 0 [mem 0x0000000000000000-0x00000001ffffffff]
> MMU: Allocated 2112 bytes of context maps for 255 contexts
> percpu: Embedded 32 pages/cpu s91736 r0 d39336 u131072
> Built 1 zonelists, mobility grouping on.  Total pages: 2064384
> Kernel command line: console=ttyS0 root=/dev/ram0
> printk: log_buf_len individual max cpu contribution: 16384 bytes
> printk: log_buf_len total cpu_extra contributions: 376832 bytes
> printk: log_buf_len min size: 131072 bytes
> printk: log_buf_len: 524288 bytes
> printk: early log buf free: 127460(97%)
> Dentry cache hash table entries: 1048576 (order: 11, 8388608 bytes, linear)
> Inode-cache hash table entries: 524288 (order: 10, 4194304 bytes, linear)
> mem auto-init: stack:off, heap alloc:off, heap free:off
> Memory: 8135632K/8388608K available (10572K kernel code, 2000K rwdata, 
> 3396K rodata, 4124K init, 358K bss, 252976K reserved, 0K cma-reserved)
> rcu: Hierarchical RCU implementation.
> rcu:    RCU event tracing is enabled.
> rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
> NR_IRQS: 512, nr_irqs: 512, preallocated irqs: 16
> mpic: Setting up MPIC " OpenPIC  " version 1.2 at fe0040000, max 24 CPUs
> mpic: ISU size: 256, shift: 8, mask: ff
> mpic: Initializing for 256 sources
> random: get_random_u64 called from .start_kernel+0x724/0x954 with 
> crng_init=0
> clocksource: timebase: mask: 0xffffffffffffffff max_cycles: 
> 0x5c4093a7d1, max_idle_ns: 440795210635 ns
> clocksource: timebase mult[2800000] 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 ...
> smp: Brought up 1 node, 24 CPUs
>
>
>
> å 2020/4/25 1:17, Daniel Axtens åé:
>> 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
>> 
>> 
>> 
>>> 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