1. 24 Jun, 2016 2 commits
  2. 20 Jun, 2016 1 commit
  3. 06 Jun, 2016 4 commits
  4. 27 May, 2016 3 commits
    • Wang Nan's avatar
      perf ctf: Convert invalid chars in a string before set value · 5ea5888b
      Wang Nan authored
      We observed some crazy apps on Android set their comm to unprintable
      string. For example:
      
        # cat /proc/10607/task/*/comm
        tencent.qqmusic
        ...
        Binder_2
        日志输出线  <-- Chinese word 'log output thread'
        WifiManager
        ...
      
      'perf data convert' fails to convert perf.data with such string to CTF format.
      
      For example:
      
        # cat << EOF > ./badguy.c
        #include <sys/prctl.h>
        int main(int argc, char *argv[])
        {
               prctl(PR_SET_NAME, "\xe6\x97\xa5\xe5\xbf\x97\xe8\xbe\x93\xe5\x87\xba\xe7\xba\xbf");
               while(1)
                       sleep(1);
               return 0;
        }
        EOF
        # gcc ./badguy.c
        # perf record -e sched:* ./a.out
        # perf data convert --to-ctf ./bad.ctf
        CTF stream 4 flush failed
        [ perf data convert: Converted 'perf.data' into CTF data './bad.ctf' ]
        [ perf data convert: Converted and wrote 0.008 MB (78 samples)  ]
        # babeltrace ./bad.ctf/
        [error] Packet size (18446744073709551615 bits) is larger than remaining file size (262144 bits).
        [error] Stream index creation error.
        [error] Open file stream error.
        [warning] [Context] Cannot open_trace of format ctf at path ./bad.ctf.
        [warning] [Context] cannot open trace "./bad.ctf" from ./bad.ctf/ for reading.
        [error] Cannot open any trace for reading.
      
        [error] opening trace "./bad.ctf/" for reading.
      
        [error] none of the specified trace paths could be opened.
      
      This patch converts unprintable characters to hexadecimal word.
      
      After applying this patch the above test works correctly:
      
        # ~/perf data convert --to-ctf ./good.ctf
        [ perf data convert: Converted 'perf.data' into CTF data './good.ctf' ]
        [ perf data convert: Converted and wrote 0.008 MB (78 samples) ]
        # babeltrace ./good.ctf
        ..
        [23:14:35.491665268] (+0.000001100) sched:sched_wakeup: { cpu_id = 4 }, { perf_ip = 0xFFFFFFFF810AEF33, perf_tid = 0, perf_pid = 0, perf_id = 5123, perf_period = 1, common_type = 270, common_flags = 45, common_preempt_count = 4, common_pid = 0, comm = "\xe6\x97\xa5\xe5\xbf\x97\xe8\xbe\x93\xe5\x87\xba\xe7\xba\xbf", pid = 1057, prio = 120, success = 1, target_cpu = 4 }
        [23:14:35.491666230] (+0.000000962) sched:sched_wakeup: { cpu_id = 4 }, { perf_ip = 0xFFFFFFFF810AEF33, perf_tid = 0, perf_pid = 0, perf_id = 5122, perf_period = 1, common_type = 270, common_flags = 45, common_preempt_count = 4, common_pid = 0, comm = "\xe6\x97\xa5\xe5\xbf\x97\xe8\xbe\x93\xe5\x87\xba\xe7\xba\xbf", pid = 1057, prio = 120, success = 1, target_cpu = 4 }
        ..
      
      Committer note:
      
      To build perf with libabeltrace, use:
      
        $ mkdir -p /tmp/build/perf
        $ make LIBBABELTRACE=1 LIBBABELTRACE_DIR=/usr/local O=/tmp/build/perf -C tools/perf install-bin
      
      Or equivalent (no O=, fixup LIBBABELTRACE_DIR, etc).
      Signed-off-by: default avatarWang Nan <wangnan0@huawei.com>
      Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: pi3orama@163.com
      Link: http://lkml.kernel.org/r/1464348951-179595-1-git-send-email-wangnan0@huawei.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      5ea5888b
    • Wang Nan's avatar
      perf record: Fix crash when kptr is restricted · 3dc6c1d5
      Wang Nan authored
      Before this patch, a simple 'perf record' could fail if kptr_restrict is
      set to 1 (for normal user) or 2 (for root):
      
        # perf record ls
        WARNING: Kernel address maps (/proc/{kallsyms,modules}) are restricted,
        check /proc/sys/kernel/kptr_restrict.
      
        Samples in kernel functions may not be resolved if a suitable vmlinux
        file is not found in the buildid cache or in the vmlinux path.
      
        Samples in kernel modules won't be resolved at all.
      
        If some relocation was applied (e.g. kexec) symbols may be misresolved
        even with a suitable vmlinux or kallsyms file.
      
        Segmentation fault (core dumped)
      
      This patch skips perf_event__synthesize_kernel_mmap() when kptr is not
      available.
      Signed-off-by: default avatarWang Nan <wangnan0@huawei.com>
      Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Fixes: 45e90056 ("perf machine: Do not bail out if not managing to read ref reloc symbol")
      Cc: Zefan Li <lizefan@huawei.com>
      Cc: pi3orama@163.com
      Link: http://lkml.kernel.org/r/1464081688-167940-2-git-send-email-wangnan0@huawei.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      3dc6c1d5
    • Wang Nan's avatar
      perf symbols: Check kptr_restrict for root · 38272dc4
      Wang Nan authored
      If kptr_restrict is set to 2, even root is not allowed to see pointers.
      This patch checks kptr_restrict even if euid == 0. For root, report
      error if kptr_restrict is 2.
      Signed-off-by: default avatarWang Nan <wangnan0@huawei.com>
      Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Zefan Li <lizefan@huawei.com>
      Cc: pi3orama@163.com
      Link: http://lkml.kernel.org/r/1464081688-167940-1-git-send-email-wangnan0@huawei.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      38272dc4
  5. 25 May, 2016 5 commits
  6. 23 May, 2016 8 commits
  7. 22 May, 2016 4 commits
  8. 20 May, 2016 13 commits