1. 25 Feb, 2022 4 commits
  2. 09 Jan, 2022 6 commits
  3. 08 Jan, 2022 5 commits
  4. 07 Jan, 2022 11 commits
  5. 06 Jan, 2022 11 commits
  6. 05 Jan, 2022 3 commits
    • Naveen N. Rao's avatar
      tracing: Tag trace_percpu_buffer as a percpu pointer · f28439db
      Naveen N. Rao authored
      Tag trace_percpu_buffer as a percpu pointer to resolve warnings
      reported by sparse:
        /linux/kernel/trace/trace.c:3218:46: warning: incorrect type in initializer (different address spaces)
        /linux/kernel/trace/trace.c:3218:46:    expected void const [noderef] __percpu *__vpp_verify
        /linux/kernel/trace/trace.c:3218:46:    got struct trace_buffer_struct *
        /linux/kernel/trace/trace.c:3234:9: warning: incorrect type in initializer (different address spaces)
        /linux/kernel/trace/trace.c:3234:9:    expected void const [noderef] __percpu *__vpp_verify
        /linux/kernel/trace/trace.c:3234:9:    got int *
      
      Link: https://lkml.kernel.org/r/ebabd3f23101d89cb75671b68b6f819f5edc830b.1640255304.git.naveen.n.rao@linux.vnet.ibm.com
      
      Cc: stable@vger.kernel.org
      Reported-by: default avatarkernel test robot <lkp@intel.com>
      Fixes: 07d777fe ("tracing: Add percpu buffers for trace_printk()")
      Signed-off-by: default avatarNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      f28439db
    • Naveen N. Rao's avatar
      tracing: Fix check for trace_percpu_buffer validity in get_trace_buf() · 823e670f
      Naveen N. Rao authored
      With the new osnoise tracer, we are seeing the below splat:
          Kernel attempted to read user page (c7d880000) - exploit attempt? (uid: 0)
          BUG: Unable to handle kernel data access on read at 0xc7d880000
          Faulting instruction address: 0xc0000000002ffa10
          Oops: Kernel access of bad area, sig: 11 [#1]
          LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
          ...
          NIP [c0000000002ffa10] __trace_array_vprintk.part.0+0x70/0x2f0
          LR [c0000000002ff9fc] __trace_array_vprintk.part.0+0x5c/0x2f0
          Call Trace:
          [c0000008bdd73b80] [c0000000001c49cc] put_prev_task_fair+0x3c/0x60 (unreliable)
          [c0000008bdd73be0] [c000000000301430] trace_array_printk_buf+0x70/0x90
          [c0000008bdd73c00] [c0000000003178b0] trace_sched_switch_callback+0x250/0x290
          [c0000008bdd73c90] [c000000000e70d60] __schedule+0x410/0x710
          [c0000008bdd73d40] [c000000000e710c0] schedule+0x60/0x130
          [c0000008bdd73d70] [c000000000030614] interrupt_exit_user_prepare_main+0x264/0x270
          [c0000008bdd73de0] [c000000000030a70] syscall_exit_prepare+0x150/0x180
          [c0000008bdd73e10] [c00000000000c174] system_call_vectored_common+0xf4/0x278
      
      osnoise tracer on ppc64le is triggering osnoise_taint() for negative
      duration in get_int_safe_duration() called from
      trace_sched_switch_callback()->thread_exit().
      
      The problem though is that the check for a valid trace_percpu_buffer is
      incorrect in get_trace_buf(). The check is being done after calculating
      the pointer for the current cpu, rather than on the main percpu pointer.
      Fix the check to be against trace_percpu_buffer.
      
      Link: https://lkml.kernel.org/r/a920e4272e0b0635cf20c444707cbce1b2c8973d.1640255304.git.naveen.n.rao@linux.vnet.ibm.com
      
      Cc: stable@vger.kernel.org
      Fixes: e2ace001 ("tracing: Choose static tp_printk buffer by explicit nesting count")
      Signed-off-by: default avatarNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      823e670f
    • Jiri Olsa's avatar
      ftrace/samples: Add missing prototypes direct functions · 0daf5cb2
      Jiri Olsa authored
      There's another compilation fail (first here [1]) reported by kernel
      test robot for W=1 clang build:
      
        >> samples/ftrace/ftrace-direct-multi-modify.c:7:6: warning: no previous
        prototype for function 'my_direct_func1' [-Wmissing-prototypes]
           void my_direct_func1(unsigned long ip)
      
      Direct functions in ftrace direct sample modules need to have prototypes
      defined. They are already global in order to be visible for the inline
      assembly, so there's no problem.
      
      The kernel test robot reported just error for ftrace-direct-multi-modify,
      but I got same errors also for the rest of the modules touched by this patch.
      
      [1] 67d4f6e3 ftrace/samples: Add missing prototype for my_direct_func
      
      Link: https://lkml.kernel.org/r/20211219135317.212430-1-jolsa@kernel.orgReported-by: default avatarkernel test robot <lkp@intel.com>
      Fixes: e1067a07 ("ftrace/samples: Add module to test multi direct modify interface")
      Fixes: ae0cc3b7 ("ftrace/samples: Add a sample module that implements modify_ftrace_direct()")
      Fixes: 156473a0 ("ftrace: Add another example of register_ftrace_direct() use case")
      Fixes: b06457c8 ("ftrace: Add sample module that uses register_ftrace_direct()")
      Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      0daf5cb2