]> git.baikalelectronics.ru Git - kernel.git/commit
perf annotate: Fix jump target outside of function address range
authorRavi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Mon, 5 Dec 2016 15:56:47 +0000 (21:26 +0530)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Thu, 15 Dec 2016 19:25:46 +0000 (16:25 -0300)
commit944aaf03d26d6d6ae4ee93d5eb880e626e7365f9
tree3a1b44e133677030fa4370460c43b0f8c88c9759
parent3eb3ebcbffbb5bb782ad0159d09a696e8d54cac3
perf annotate: Fix jump target outside of function address range

If jump target is outside of function range, perf is not handling it
correctly. Especially when target address is lesser than function start
address, target offset will be negative. But, target address declared to
be unsigned, converts negative number into 2's complement. See below
example. Here target of 'jumpq' instruction at 34cf8 is 34ac0 which is
lesser than function start address(34cf0).

        34ac0 - 34cf0 = -0x230 = 0xfffffffffffffdd0

Objdump output:

  0000000000034cf0 <__sigaction>:
  __GI___sigaction():
    34cf0: lea    -0x20(%rdi),%eax
    34cf3: cmp    -bashx1,%eax
    34cf6: jbe    34d00 <__sigaction+0x10>
    34cf8: jmpq   34ac0 <__GI___libc_sigaction>
    34cfd: nopl   (%rax)
    34d00: mov    0x386161(%rip),%rax        # 3bae68 <_DYNAMIC+0x2e8>
    34d07: movl   -bashx16,%fs:(%rax)
    34d0e: mov    -bashxffffffff,%eax
    34d13: retq

perf annotate before applying patch:

  __GI___sigaction  /usr/lib64/libc-2.22.so
           lea    -0x20(%rdi),%eax
           cmp    -bashx1,%eax
        v  jbe    10
        v  jmpq   fffffffffffffdd0
           nop
    10:    mov    _DYNAMIC+0x2e8,%rax
           movl   -bashx16,%fs:(%rax)
           mov    -bashxffffffff,%eax
           retq

perf annotate after applying patch:

  __GI___sigaction  /usr/lib64/libc-2.22.so
           lea    -0x20(%rdi),%eax
           cmp    -bashx1,%eax
        v  jbe    10
        ^  jmpq   34ac0 <__GI___libc_sigaction>
           nop
    10:    mov    _DYNAMIC+0x2e8,%rax
           movl   -bashx16,%fs:(%rax)
           mov    -bashxffffffff,%eax
           retq

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Chris Riyder <chris.ryder@arm.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1480953407-7605-3-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools/perf/ui/browsers/annotate.c
tools/perf/util/annotate.c
tools/perf/util/annotate.h