Hi, A bug was opened for this just a few days ago - 7133122.
I'll add your patch to the CR. David Holmes ------------ On 31/01/2012 8:32 PM, Yasumasa Suenaga wrote: > Hi, > > I've tried attach a corefile with jstack. However, I couldn't. > > I guess that this problem is caused by incorrect address mapping of > libsaproc.so . > I've made a patch which is attached this email. And I've been able to get > correct thread stack with jstack. > > So, I'd like to contribute this patch, and I'd like to backport to JDK6/7 . > Could you help me? > > > ------ details ------ > > I got these messages then I ran jstack with LIBSAPROC_DEBUG environment > variable: > > /*************************/ > > : > > libsaproc DEBUG: reading library > /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.1.x86_64/jre/lib/amd64/server/libjvm.so > @ 0x7f53b455a000 [ 0x7f53b455a000 ] > libsaproc DEBUG: ---- sorted virtual address map ---- > > : > > libsaproc DEBUG: base = 0x7f53b455a000 size = 9993772 > libsaproc DEBUG: base = 0x7f53b455a000 size = 4096 > > : > > libsaproc DEBUG: can't locate map_info at 0x7f53b4dbe000 > libsaproc DEBUG: core read failed for 4096 byte(s) @ 0x7f53b4dbe000 (4096 > more bytes) > > : > > /*************************/ > > libsaproc.so tries to read libjvm.so library address, and it is duplicated. > I read Linux kernel source code of function of core dump, and I found these > comment: > > source code: kernel-3.2.1-3.fc16.src.rpm (Fedora16 x86_64) > in fs/binfmt_elf.c: static unsigned long vma_dump_size(struct vm_area_struct > *vma, unsigned long mm_flags) > ---------------------- > /* > * If this looks like the beginning of a DSO or executable mapping, > * check for an ELF header. If we find one, dump the first page to > * aid in determining what was mapped here. > */ > ---------------------- > > In fact, core image has executable load section which size is 1 page(0x1000) > ---------------------- > LOAD 0x0000000005173000 0x00007f53b455a000 0x0000000000000000 > 0x0000000000001000 0x0000000000988000 R E 1000 > ---------------------- > > So, we must think these case when we attach core image. > I modified "read_lib_segments()" in hotspot/agent/src/os/linux/ps_core.c to > overwrite > correct address in shared library . > > > Please check it. > > Thanks, > Yasumasa >
