Mercurial > jdk8-mips64-public > hotspot / changeset

     1.1 --- a/agent/src/os/linux/ps_core.c	Tue Jun 18 09:33:34 2019 -0400
     1.2 +++ b/agent/src/os/linux/ps_core.c	Wed Jun 19 09:42:12 2019 +0900
     1.3 @@ -865,8 +865,51 @@
     1.4  #define LD_BASE_OFFSET        offsetof(struct r_debug,  r_ldbase)
     1.5  #define LINK_MAP_ADDR_OFFSET  offsetof(struct link_map, l_addr)
     1.6  #define LINK_MAP_NAME_OFFSET  offsetof(struct link_map, l_name)
     1.7 +#define LINK_MAP_LD_OFFSET    offsetof(struct link_map, l_ld)
     1.8  #define LINK_MAP_NEXT_OFFSET  offsetof(struct link_map, l_next)
     1.9  
    1.10 +// Calculate the load address of shared library
    1.11 +// on prelink-enabled environment.
    1.12 +//
    1.13 +// In case of GDB, it would be calculated by offset of link_map.l_ld
    1.14 +// and the address of .dynamic section.
    1.15 +// See GDB implementation: lm_addr_check @ solib-svr4.c
    1.16 +static uintptr_t calc_prelinked_load_address(struct ps_prochandle* ph, int lib_fd, ELF_EHDR* elf_ehdr, uintptr_t link_map_addr) {
    1.17 +  ELF_PHDR *phbuf;
    1.18 +  uintptr_t lib_ld;
    1.19 +  uintptr_t lib_dyn_addr = 0L;
    1.20 +  uintptr_t load_addr;
    1.21 +  int i;
    1.22 +
    1.23 +  phbuf = read_program_header_table(lib_fd, elf_ehdr);
    1.24 +  if (phbuf == NULL) {
    1.25 +    print_debug("can't read program header of shared object\n");
    1.26 +    return 0L;
    1.27 +  }
    1.28 +
    1.29 +  // Get the address of .dynamic section from shared library.
    1.30 +  for (i = 0; i < elf_ehdr->e_phnum; i++) {
    1.31 +    if (phbuf[i].p_type == PT_DYNAMIC) {
    1.32 +      lib_dyn_addr = phbuf[i].p_vaddr;
    1.33 +      break;
    1.34 +    }
    1.35 +  }
    1.36 +
    1.37 +  free(phbuf);
    1.38 +
    1.39 +  if (ps_pdread(ph, (psaddr_t)link_map_addr + LINK_MAP_LD_OFFSET,
    1.40 +               &lib_ld, sizeof(uintptr_t)) != PS_OK) {
    1.41 +    print_debug("can't read address of dynamic section in shared object\n");
    1.42 +    return 0L;
    1.43 +  }
    1.44 +
    1.45 +  // Return the load address which is calculated by the address of .dynamic
    1.46 +  // and link_map.l_ld .
    1.47 +  load_addr = lib_ld - lib_dyn_addr;
    1.48 +  print_debug("lib_ld = 0x%lx, lib_dyn_addr = 0x%lx -> lib_base_diff = 0x%lx\n", lib_ld, lib_dyn_addr, load_addr);
    1.49 +  return load_addr;
    1.50 +}
    1.51 +
    1.52  // read shared library info from runtime linker's data structures.
    1.53  // This work is done by librtlb_db in Solaris
    1.54  static bool read_shared_lib_info(struct ps_prochandle* ph) {
    1.55 @@ -968,6 +1011,14 @@
    1.56              // continue with other libraries...
    1.57           } else {
    1.58              if (read_elf_header(lib_fd, &elf_ehdr)) {
    1.59 +               if (lib_base_diff == 0x0L) {
    1.60 +                 lib_base_diff = calc_prelinked_load_address(ph, lib_fd, &elf_ehdr, link_map_addr);
    1.61 +                 if (lib_base_diff == 0x0L) {
    1.62 +                   close(lib_fd);
    1.63 +                   return false;
    1.64 +                 }
    1.65 +               }
    1.66 +
    1.67                 lib_base = lib_base_diff + find_base_address(lib_fd, &elf_ehdr);
    1.68                 print_debug("reading library %s @ 0x%lx [ 0x%lx ]\n",
    1.69                             lib_name, lib_base, lib_base_diff);