1. 16 Oct, 2017 8 commits
  2. 13 Oct, 2017 3 commits
  3. 10 Oct, 2017 1 commit
  4. 06 Oct, 2017 7 commits
  5. 05 Oct, 2017 2 commits
    • Naveen N. Rao's avatar
      powerpc/jprobes: Validate break handler invocation as being due to a jprobe_return() · 3368f569
      Naveen N. Rao authored
      Fix a circa 2005 FIXME by implementing a check to ensure that we
      actually got into the jprobe break handler() due to the trap in
      jprobe_return().
      Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
      Signed-off-by: default avatarNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      3368f569
    • Naveen N. Rao's avatar
      powerpc/jprobes: Disable preemption when triggered through ftrace · 6baea433
      Naveen N. Rao authored
      KPROBES_SANITY_TEST throws the below splat when CONFIG_PREEMPT is
      enabled:
      
        Kprobe smoke test: started
        DEBUG_LOCKS_WARN_ON(val > preempt_count())
        ------------[ cut here ]------------
        WARNING: CPU: 19 PID: 1 at kernel/sched/core.c:3094 preempt_count_sub+0xcc/0x140
        Modules linked in:
        CPU: 19 PID: 1 Comm: swapper/0 Not tainted 4.13.0-rc7-nnr+ #97
        task: c0000000fea80000 task.stack: c0000000feb00000
        NIP:  c00000000011d3dc LR: c00000000011d3d8 CTR: c000000000a090d0
        REGS: c0000000feb03400 TRAP: 0700   Not tainted  (4.13.0-rc7-nnr+)
        MSR:  8000000000021033 <SF,ME,IR,DR,RI,LE>  CR: 28000282  XER: 00000000
        CFAR: c00000000015aa18 SOFTE: 0
        <snip>
        NIP preempt_count_sub+0xcc/0x140
        LR  preempt_count_sub+0xc8/0x140
        Call Trace:
          preempt_count_sub+0xc8/0x140 (unreliable)
          kprobe_handler+0x228/0x4b0
          program_check_exception+0x58/0x3b0
          program_check_common+0x16c/0x170
          --- interrupt: 0 at kprobe_target+0x8/0x20
                           LR = init_test_probes+0x248/0x7d0
          kp+0x0/0x80 (unreliable)
          livepatch_handler+0x38/0x74
          init_kprobes+0x1d8/0x208
          do_one_initcall+0x68/0x1d0
          kernel_init_freeable+0x298/0x374
          kernel_init+0x24/0x160
          ret_from_kernel_thread+0x5c/0x70
        Instruction dump:
        419effdc 3d22001b 39299240 81290000 2f890000 409effc8 3c82ffcb 3c62ffcb
        3884bc68 3863bc18 4803d5fd 60000000 <0fe00000> 4bffffa8 60000000 60000000
        ---[ end trace 432dd46b4ce3d29f ]---
        Kprobe smoke test: passed successfully
      
      The issue is that we aren't disabling preemption in
      kprobe_ftrace_handler(). Disable it.
      
      Fixes: ead514d5 ("powerpc/kprobes: Add support for KPROBES_ON_FTRACE")
      Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
      Signed-off-by: default avatarNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      [mpe: Trim oops a little for formatting]
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      6baea433
  6. 04 Oct, 2017 18 commits
  7. 03 Oct, 2017 1 commit