| /* |
| * Copyright (c) 2012, 2013 SAP SE. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "asm/assembler.hpp" |
| #include "compiler/disassembler.hpp" |
| #include "loadlib_aix.hpp" |
| #include "memory/allocation.hpp" |
| #include "memory/allocation.inline.hpp" |
| #include "misc_aix.hpp" |
| #include "porting_aix.hpp" |
| #include "runtime/os.hpp" |
| #include "runtime/thread.hpp" |
| #include "utilities/align.hpp" |
| #include "utilities/debug.hpp" |
| |
| #include <demangle.h> |
| #include <sys/debug.h> |
| #include <pthread.h> |
| #include <ucontext.h> |
| |
| ////////////////////////////////// |
| // Provide implementation for dladdr based on LoadedLibraries pool and |
| // traceback table scan |
| |
| // Search traceback table in stack, |
| // return procedure name from trace back table. |
| #define MAX_FUNC_SEARCH_LEN 0x10000 |
| |
| #define PTRDIFF_BYTES(p1,p2) (((ptrdiff_t)p1) - ((ptrdiff_t)p2)) |
| |
| // Typedefs for stackslots, stack pointers, pointers to op codes. |
| typedef unsigned long stackslot_t; |
| typedef stackslot_t* stackptr_t; |
| typedef unsigned int* codeptr_t; |
| |
| // Unfortunately, the interface of dladdr makes the implementator |
| // responsible for maintaining memory for function name/library |
| // name. I guess this is because most OS's keep those values as part |
| // of the mapped executable image ready to use. On AIX, this doesn't |
| // work, so I have to keep the returned strings. For now, I do this in |
| // a primitive string map. Should this turn out to be a performance |
| // problem, a better hashmap has to be used. |
| class fixed_strings { |
| struct node : public CHeapObj<mtInternal> { |
| char* v; |
| node* next; |
| }; |
| |
| node* first; |
| |
| public: |
| |
| fixed_strings() : first(0) {} |
| ~fixed_strings() { |
| node* n = first; |
| while (n) { |
| node* p = n; |
| n = n->next; |
| os::free(p->v); |
| delete p; |
| } |
| } |
| |
| char* intern(const char* s) { |
| for (node* n = first; n; n = n->next) { |
| if (strcmp(n->v, s) == 0) { |
| return n->v; |
| } |
| } |
| node* p = new node; |
| p->v = os::strdup_check_oom(s); |
| p->next = first; |
| first = p; |
| return p->v; |
| } |
| }; |
| |
| static fixed_strings dladdr_fixed_strings; |
| |
| bool AixSymbols::get_function_name ( |
| address pc0, // [in] program counter |
| char* p_name, size_t namelen, // [out] optional: function name ("" if not available) |
| int* p_displacement, // [out] optional: displacement (-1 if not available) |
| const struct tbtable** p_tb, // [out] optional: ptr to traceback table to get further |
| // information (NULL if not available) |
| bool demangle // [in] whether to demangle the name |
| ) { |
| struct tbtable* tb = 0; |
| unsigned int searchcount = 0; |
| |
| // initialize output parameters |
| if (p_name && namelen > 0) { |
| *p_name = '\0'; |
| } |
| if (p_displacement) { |
| *p_displacement = -1; |
| } |
| if (p_tb) { |
| *p_tb = NULL; |
| } |
| |
| codeptr_t pc = (codeptr_t)pc0; |
| |
| // weed out obvious bogus states |
| if (pc < (codeptr_t)0x1000) { |
| trcVerbose("invalid program counter"); |
| return false; |
| } |
| |
| // We see random but frequent crashes in this function since some months mainly on shutdown |
| // (-XX:+DumpInfoAtExit). It appears the page we are reading is randomly disappearing while |
| // we read it (?). |
| // As the pc cannot be trusted to be anything sensible lets make all reads via SafeFetch. Also |
| // bail if this is not a text address right now. |
| if (!LoadedLibraries::find_for_text_address(pc, NULL)) { |
| trcVerbose("not a text address"); |
| return false; |
| } |
| |
| // .. (Note that is_readable_pointer returns true if safefetch stubs are not there yet; |
| // in that case I try reading the traceback table unsafe - I rather risk secondary crashes in |
| // error files than not having a callstack.) |
| #define CHECK_POINTER_READABLE(p) \ |
| if (!MiscUtils::is_readable_pointer(p)) { \ |
| trcVerbose("pc not readable"); \ |
| return false; \ |
| } |
| |
| codeptr_t pc2 = (codeptr_t) pc; |
| |
| // Make sure the pointer is word aligned. |
| pc2 = (codeptr_t) align_up((char*)pc2, 4); |
| CHECK_POINTER_READABLE(pc2) |
| |
| // Find start of traceback table. |
| // (starts after code, is marked by word-aligned (32bit) zeros) |
| while ((*pc2 != NULL) && (searchcount++ < MAX_FUNC_SEARCH_LEN)) { |
| CHECK_POINTER_READABLE(pc2) |
| pc2++; |
| } |
| if (*pc2 != 0) { |
| trcVerbose("no traceback table found"); |
| return false; |
| } |
| // |
| // Set up addressability to the traceback table |
| // |
| tb = (struct tbtable*) (pc2 + 1); |
| |
| // Is this really a traceback table? No way to be sure but |
| // some indicators we can check. |
| if (tb->tb.lang >= 0xf && tb->tb.lang <= 0xfb) { |
| // Language specifiers, go from 0 (C) to 14 (Objective C). |
| // According to spec, 0xf-0xfa reserved, 0xfb-0xff reserved for ibm. |
| trcVerbose("no traceback table found"); |
| return false; |
| } |
| |
| // Existence of fields in the tbtable extension are contingent upon |
| // specific fields in the base table. Check for their existence so |
| // that we can address the function name if it exists. |
| pc2 = (codeptr_t) tb + |
| sizeof(struct tbtable_short)/sizeof(int); |
| if (tb->tb.fixedparms != 0 || tb->tb.floatparms != 0) |
| pc2++; |
| |
| CHECK_POINTER_READABLE(pc2) |
| |
| if (tb->tb.has_tboff == TRUE) { |
| |
| // I want to know the displacement |
| const unsigned int tb_offset = *pc2; |
| codeptr_t start_of_procedure = |
| (codeptr_t)(((char*)tb) - 4 - tb_offset); // (-4 to omit leading 0000) |
| |
| // Weed out the cases where we did find the wrong traceback table. |
| if (pc < start_of_procedure) { |
| trcVerbose("no traceback table found"); |
| return false; |
| } |
| |
| // return the displacement |
| if (p_displacement) { |
| (*p_displacement) = (int) PTRDIFF_BYTES(pc, start_of_procedure); |
| } |
| |
| pc2++; |
| } else { |
| // return -1 for displacement |
| if (p_displacement) { |
| (*p_displacement) = -1; |
| } |
| } |
| |
| if (tb->tb.int_hndl == TRUE) |
| pc2++; |
| |
| if (tb->tb.has_ctl == TRUE) |
| pc2 += (*pc2) + 1; // don't care |
| |
| CHECK_POINTER_READABLE(pc2) |
| |
| // |
| // return function name if it exists. |
| // |
| if (p_name && namelen > 0) { |
| if (tb->tb.name_present) { |
| // Copy name from text because it may not be zero terminated. |
| const short l = MIN2<short>(*((short*)pc2), namelen - 1); |
| // Be very careful. |
| int i = 0; char* const p = (char*)pc2 + sizeof(short); |
| while (i < l && MiscUtils::is_readable_pointer(p + i)) { |
| p_name[i] = p[i]; |
| i++; |
| } |
| p_name[i] = '\0'; |
| |
| // If it is a C++ name, try and demangle it using the Demangle interface (see demangle.h). |
| if (demangle) { |
| char* rest; |
| Name* const name = Demangle(p_name, rest); |
| if (name) { |
| const char* const demangled_name = name->Text(); |
| if (demangled_name) { |
| strncpy(p_name, demangled_name, namelen-1); |
| p_name[namelen-1] = '\0'; |
| } |
| delete name; |
| } |
| } |
| } else { |
| strncpy(p_name, "<nameless function>", namelen-1); |
| p_name[namelen-1] = '\0'; |
| } |
| } |
| |
| // Return traceback table, if user wants it. |
| if (p_tb) { |
| (*p_tb) = tb; |
| } |
| |
| return true; |
| |
| } |
| |
| bool AixSymbols::get_module_name(address pc, |
| char* p_name, size_t namelen) { |
| |
| if (p_name && namelen > 0) { |
| p_name[0] = '\0'; |
| loaded_module_t lm; |
| if (LoadedLibraries::find_for_text_address(pc, &lm) != NULL) { |
| strncpy(p_name, lm.shortname, namelen); |
| p_name[namelen - 1] = '\0'; |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| // Special implementation of dladdr for Aix based on LoadedLibraries |
| // Note: dladdr returns non-zero for ok, 0 for error! |
| // Note: dladdr is not posix, but a non-standard GNU extension. So this tries to |
| // fulfill the contract of dladdr on Linux (see http://linux.die.net/man/3/dladdr) |
| // Note: addr may be both an AIX function descriptor or a real code pointer |
| // to the entry of a function. |
| extern "C" |
| int dladdr(void* addr, Dl_info* info) { |
| |
| if (!addr) { |
| return 0; |
| } |
| |
| assert(info, ""); |
| |
| int rc = 0; |
| |
| const char* const ZEROSTRING = ""; |
| |
| // Always return a string, even if a "" one. Linux dladdr manpage |
| // does not say anything about returning NULL |
| info->dli_fname = ZEROSTRING; |
| info->dli_sname = ZEROSTRING; |
| info->dli_saddr = NULL; |
| |
| address p = (address) addr; |
| loaded_module_t lm; |
| bool found = false; |
| |
| enum { noclue, code, data } type = noclue; |
| |
| trcVerbose("dladdr(%p)...", p); |
| |
| // Note: input address may be a function. I accept both a pointer to |
| // the entry of a function and a pointer to the function decriptor. |
| // (see ppc64 ABI) |
| found = LoadedLibraries::find_for_text_address(p, &lm); |
| if (found) { |
| type = code; |
| } |
| |
| if (!found) { |
| // Not a pointer into any text segment. Is it a function descriptor? |
| const FunctionDescriptor* const pfd = (const FunctionDescriptor*) p; |
| p = pfd->entry(); |
| if (p) { |
| found = LoadedLibraries::find_for_text_address(p, &lm); |
| if (found) { |
| type = code; |
| } |
| } |
| } |
| |
| if (!found) { |
| // Neither direct code pointer nor function descriptor. A data ptr? |
| p = (address)addr; |
| found = LoadedLibraries::find_for_data_address(p, &lm); |
| if (found) { |
| type = data; |
| } |
| } |
| |
| // If we did find the shared library this address belongs to (either |
| // code or data segment) resolve library path and, if possible, the |
| // symbol name. |
| if (found) { |
| |
| // No need to intern the libpath, that one is already interned one layer below. |
| info->dli_fname = lm.path; |
| |
| if (type == code) { |
| |
| // For code symbols resolve function name and displacement. Use |
| // displacement to calc start of function. |
| char funcname[256] = ""; |
| int displacement = 0; |
| |
| if (AixSymbols::get_function_name(p, funcname, sizeof(funcname), |
| &displacement, NULL, true)) { |
| if (funcname[0] != '\0') { |
| const char* const interned = dladdr_fixed_strings.intern(funcname); |
| info->dli_sname = interned; |
| trcVerbose("... function name: %s ...", interned); |
| } |
| |
| // From the displacement calculate the start of the function. |
| if (displacement != -1) { |
| info->dli_saddr = p - displacement; |
| } else { |
| info->dli_saddr = p; |
| } |
| } else { |
| |
| // No traceback table found. Just assume the pointer is it. |
| info->dli_saddr = p; |
| |
| } |
| |
| } else if (type == data) { |
| |
| // For data symbols. |
| info->dli_saddr = p; |
| |
| } else { |
| ShouldNotReachHere(); |
| } |
| |
| rc = 1; // success: return 1 [sic] |
| |
| } |
| |
| // sanity checks. |
| if (rc) { |
| assert(info->dli_fname, ""); |
| assert(info->dli_sname, ""); |
| assert(info->dli_saddr, ""); |
| } |
| |
| return rc; // error: return 0 [sic] |
| |
| } |
| |
| ///////////////////////////////////////////////////////////////////////////// |
| // Native callstack dumping |
| |
| // Print the traceback table for one stack frame. |
| static void print_tbtable (outputStream* st, const struct tbtable* p_tb) { |
| |
| if (p_tb == NULL) { |
| st->print("<null>"); |
| return; |
| } |
| |
| switch(p_tb->tb.lang) { |
| case TB_C: st->print("C"); break; |
| case TB_FORTRAN: st->print("FORTRAN"); break; |
| case TB_PASCAL: st->print("PASCAL"); break; |
| case TB_ADA: st->print("ADA"); break; |
| case TB_PL1: st->print("PL1"); break; |
| case TB_BASIC: st->print("BASIC"); break; |
| case TB_LISP: st->print("LISP"); break; |
| case TB_COBOL: st->print("COBOL"); break; |
| case TB_MODULA2: st->print("MODULA2"); break; |
| case TB_CPLUSPLUS: st->print("C++"); break; |
| case TB_RPG: st->print("RPG"); break; |
| case TB_PL8: st->print("PL8"); break; |
| case TB_ASM: st->print("ASM"); break; |
| case TB_HPJ: st->print("HPJ"); break; |
| default: st->print("unknown"); |
| } |
| st->print(" "); |
| |
| if (p_tb->tb.globallink) { |
| st->print("globallink "); |
| } |
| if (p_tb->tb.is_eprol) { |
| st->print("eprol "); |
| } |
| if (p_tb->tb.int_proc) { |
| st->print("int_proc "); |
| } |
| if (p_tb->tb.tocless) { |
| st->print("tocless "); |
| } |
| if (p_tb->tb.fp_present) { |
| st->print("fp_present "); |
| } |
| if (p_tb->tb.int_hndl) { |
| st->print("interrupt_handler "); |
| } |
| if (p_tb->tb.uses_alloca) { |
| st->print("uses_alloca "); |
| } |
| if (p_tb->tb.saves_cr) { |
| st->print("saves_cr "); |
| } |
| if (p_tb->tb.saves_lr) { |
| st->print("saves_lr "); |
| } |
| if (p_tb->tb.stores_bc) { |
| st->print("stores_bc "); |
| } |
| if (p_tb->tb.fixup) { |
| st->print("fixup "); |
| } |
| if (p_tb->tb.fpr_saved > 0) { |
| st->print("fpr_saved:%d ", p_tb->tb.fpr_saved); |
| } |
| if (p_tb->tb.gpr_saved > 0) { |
| st->print("gpr_saved:%d ", p_tb->tb.gpr_saved); |
| } |
| if (p_tb->tb.fixedparms > 0) { |
| st->print("fixedparms:%d ", p_tb->tb.fixedparms); |
| } |
| if (p_tb->tb.floatparms > 0) { |
| st->print("floatparms:%d ", p_tb->tb.floatparms); |
| } |
| if (p_tb->tb.parmsonstk > 0) { |
| st->print("parmsonstk:%d", p_tb->tb.parmsonstk); |
| } |
| } |
| |
| // Print information for pc (module, function, displacement, traceback table) |
| // on one line. |
| static void print_info_for_pc (outputStream* st, codeptr_t pc, char* buf, |
| size_t buf_size, bool demangle) { |
| const struct tbtable* tb = NULL; |
| int displacement = -1; |
| |
| if (!MiscUtils::is_readable_pointer(pc)) { |
| st->print("(invalid)"); |
| return; |
| } |
| |
| if (AixSymbols::get_module_name((address)pc, buf, buf_size)) { |
| st->print("%s", buf); |
| } else { |
| st->print("(unknown module)"); |
| } |
| st->print("::"); |
| if (AixSymbols::get_function_name((address)pc, buf, buf_size, |
| &displacement, &tb, demangle)) { |
| st->print("%s", buf); |
| } else { |
| st->print("(unknown function)"); |
| } |
| if (displacement == -1) { |
| st->print("+?"); |
| } else { |
| st->print("+0x%x", displacement); |
| } |
| if (tb) { |
| st->fill_to(64); |
| st->print(" ("); |
| print_tbtable(st, tb); |
| st->print(")"); |
| } |
| } |
| |
| static void print_stackframe(outputStream* st, stackptr_t sp, char* buf, |
| size_t buf_size, bool demangle) { |
| |
| stackptr_t sp2 = sp; |
| |
| // skip backchain |
| |
| sp2++; |
| |
| // skip crsave |
| |
| sp2++; |
| |
| // retrieve lrsave. That is the only info I need to get the function/displacement |
| |
| codeptr_t lrsave = (codeptr_t) *(sp2); |
| st->print (PTR64_FORMAT " - " PTR64_FORMAT " ", sp2, lrsave); |
| |
| if (lrsave != NULL) { |
| print_info_for_pc(st, lrsave, buf, buf_size, demangle); |
| } |
| |
| } |
| |
| // Function to check a given stack pointer against given stack limits. |
| static bool is_valid_stackpointer(stackptr_t sp, stackptr_t stack_base, size_t stack_size) { |
| if (((uintptr_t)sp) & 0x7) { |
| return false; |
| } |
| if (sp > stack_base) { |
| return false; |
| } |
| if (sp < (stackptr_t) ((address)stack_base - stack_size)) { |
| return false; |
| } |
| return true; |
| } |
| |
| // Returns true if function is a valid codepointer. |
| static bool is_valid_codepointer(codeptr_t p) { |
| if (!p) { |
| return false; |
| } |
| if (((uintptr_t)p) & 0x3) { |
| return false; |
| } |
| if (LoadedLibraries::find_for_text_address(p, NULL) == NULL) { |
| return false; |
| } |
| return true; |
| } |
| |
| // Function tries to guess if the given combination of stack pointer, stack base |
| // and stack size is a valid stack frame. |
| static bool is_valid_frame (stackptr_t p, stackptr_t stack_base, size_t stack_size) { |
| |
| if (!is_valid_stackpointer(p, stack_base, stack_size)) { |
| return false; |
| } |
| |
| // First check - the occurrence of a valid backchain pointer up the stack, followed by a |
| // valid codeptr, counts as a good candidate. |
| stackptr_t sp2 = (stackptr_t) *p; |
| if (is_valid_stackpointer(sp2, stack_base, stack_size) && // found a valid stack pointer in the stack... |
| ((sp2 - p) > 6) && // ... pointing upwards and not into my frame... |
| is_valid_codepointer((codeptr_t)(*(sp2 + 2)))) // ... followed by a code pointer after two slots... |
| { |
| return true; |
| } |
| |
| return false; |
| } |
| |
| // Try to relocate a stack back chain in a given stack. |
| // Used in callstack dumping, when the backchain is broken by an overwriter |
| static stackptr_t try_find_backchain (stackptr_t last_known_good_frame, |
| stackptr_t stack_base, size_t stack_size) |
| { |
| if (!is_valid_stackpointer(last_known_good_frame, stack_base, stack_size)) { |
| return NULL; |
| } |
| |
| stackptr_t sp = last_known_good_frame; |
| |
| sp += 6; // Omit next fixed frame slots. |
| while (sp < stack_base) { |
| if (is_valid_frame(sp, stack_base, stack_size)) { |
| return sp; |
| } |
| sp ++; |
| } |
| |
| return NULL; |
| } |
| |
| static void decode_instructions_at_pc(const char* header, |
| codeptr_t pc, int num_before, |
| int num_after, outputStream* st) { |
| // TODO: PPC port Disassembler::decode(pc, 16, 16, st); |
| } |
| |
| |
| void AixNativeCallstack::print_callstack_for_context(outputStream* st, const ucontext_t* context, |
| bool demangle, char* buf, size_t buf_size) { |
| |
| #define MAX_CALLSTACK_DEPTH 50 |
| |
| unsigned long* sp; |
| unsigned long* sp_last; |
| int frame; |
| |
| // To print the first frame, use the current value of iar: |
| // current entry indicated by iar (the current pc) |
| codeptr_t cur_iar = 0; |
| stackptr_t cur_sp = 0; |
| codeptr_t cur_rtoc = 0; |
| codeptr_t cur_lr = 0; |
| |
| const ucontext_t* uc = (const ucontext_t*) context; |
| |
| // fallback: use the current context |
| ucontext_t local_context; |
| if (!uc) { |
| st->print_cr("No context given, using current context."); |
| if (getcontext(&local_context) == 0) { |
| uc = &local_context; |
| } else { |
| st->print_cr("No context given and getcontext failed. "); |
| return; |
| } |
| } |
| |
| cur_iar = (codeptr_t)uc->uc_mcontext.jmp_context.iar; |
| cur_sp = (stackptr_t)uc->uc_mcontext.jmp_context.gpr[1]; |
| cur_rtoc = (codeptr_t)uc->uc_mcontext.jmp_context.gpr[2]; |
| cur_lr = (codeptr_t)uc->uc_mcontext.jmp_context.lr; |
| |
| // syntax used here: |
| // n -------------- <-- stack_base, stack_to |
| // n-1 | | |
| // ... | older | |
| // ... | frames | | |
| // | | | stack grows downward |
| // ... | younger | | |
| // ... | frames | V |
| // | | |
| // |------------| <-- cur_sp, current stack ptr |
| // | | |
| // | unsused | |
| // | stack | |
| // | | |
| // . . |
| // . . |
| // . . |
| // . . |
| // | | |
| // 0 -------------- <-- stack_from |
| // |
| |
| // Retrieve current stack base, size from the current thread. If there is none, |
| // retrieve it from the OS. |
| stackptr_t stack_base = NULL; |
| size_t stack_size = NULL; |
| { |
| AixMisc::stackbounds_t stackbounds; |
| if (!AixMisc::query_stack_bounds_for_current_thread(&stackbounds)) { |
| st->print_cr("Cannot retrieve stack bounds."); |
| return; |
| } |
| stack_base = (stackptr_t)stackbounds.base; |
| stack_size = stackbounds.size; |
| } |
| |
| st->print_cr("------ current frame:"); |
| st->print("iar: " PTR64_FORMAT " ", p2i(cur_iar)); |
| print_info_for_pc(st, cur_iar, buf, buf_size, demangle); |
| st->cr(); |
| |
| if (cur_iar && MiscUtils::is_readable_pointer(cur_iar)) { |
| decode_instructions_at_pc( |
| "Decoded instructions at iar:", |
| cur_iar, 32, 16, st); |
| } |
| |
| // Print out lr too, which may be interesting if we did jump to some bogus location; |
| // in those cases the new frame is not built up yet and the caller location is only |
| // preserved via lr register. |
| st->print("lr: " PTR64_FORMAT " ", p2i(cur_lr)); |
| print_info_for_pc(st, cur_lr, buf, buf_size, demangle); |
| st->cr(); |
| |
| if (cur_lr && MiscUtils::is_readable_pointer(cur_lr)) { |
| decode_instructions_at_pc( |
| "Decoded instructions at lr:", |
| cur_lr, 32, 16, st); |
| } |
| |
| // Check and print sp. |
| st->print("sp: " PTR64_FORMAT " ", p2i(cur_sp)); |
| if (!is_valid_stackpointer(cur_sp, stack_base, stack_size)) { |
| st->print("(invalid) "); |
| goto cleanup; |
| } else { |
| st->print("(base - 0x%X) ", PTRDIFF_BYTES(stack_base, cur_sp)); |
| } |
| st->cr(); |
| |
| // Check and print rtoc. |
| st->print("rtoc: " PTR64_FORMAT " ", p2i(cur_rtoc)); |
| if (cur_rtoc == NULL || cur_rtoc == (codeptr_t)-1 || |
| !MiscUtils::is_readable_pointer(cur_rtoc)) { |
| st->print("(invalid)"); |
| } else if (((uintptr_t)cur_rtoc) & 0x7) { |
| st->print("(unaligned)"); |
| } |
| st->cr(); |
| |
| st->print_cr("|---stackaddr----| |----lrsave------|: <function name>"); |
| |
| /// |
| // Walk callstack. |
| // |
| // (if no context was given, use the current stack) |
| sp = (unsigned long*)(*(unsigned long*)cur_sp); // Stack pointer |
| sp_last = cur_sp; |
| |
| frame = 0; |
| |
| while (frame < MAX_CALLSTACK_DEPTH) { |
| |
| // Check sp. |
| bool retry = false; |
| if (sp == NULL) { |
| // The backchain pointer was NULL. This normally means the end of the chain. But the |
| // stack might be corrupted, and it may be worth looking for the stack chain. |
| if (is_valid_stackpointer(sp_last, stack_base, stack_size) && (stack_base - 0x10) > sp_last) { |
| // If we are not within <guess> 0x10 stackslots of the stack base, we assume that this |
| // is indeed not the end of the chain but that the stack was corrupted. So lets try to |
| // find the end of the chain. |
| st->print_cr("*** back chain pointer is NULL - end of stack or broken backchain ? ***"); |
| retry = true; |
| } else { |
| st->print_cr("*** end of backchain ***"); |
| goto end_walk_callstack; |
| } |
| } else if (!is_valid_stackpointer(sp, stack_base, stack_size)) { |
| st->print_cr("*** stack pointer invalid - backchain corrupted (" PTR_FORMAT ") ***", p2i(sp)); |
| retry = true; |
| } else if (sp < sp_last) { |
| st->print_cr("invalid stack pointer: " PTR_FORMAT " (not monotone raising)", p2i(sp)); |
| retry = true; |
| } |
| |
| // If backchain is broken, try to recover, by manually scanning the stack for a pattern |
| // which looks like a valid stack. |
| if (retry) { |
| st->print_cr("trying to recover and find backchain..."); |
| sp = try_find_backchain(sp_last, stack_base, stack_size); |
| if (sp) { |
| st->print_cr("found something which looks like a backchain at " PTR64_FORMAT ", after 0x%x bytes... ", |
| p2i(sp), PTRDIFF_BYTES(sp, sp_last)); |
| } else { |
| st->print_cr("did not find a backchain, giving up."); |
| goto end_walk_callstack; |
| } |
| } |
| |
| // Print stackframe. |
| print_stackframe(st, sp, buf, buf_size, demangle); |
| st->cr(); |
| frame ++; |
| |
| // Next stack frame and link area. |
| sp_last = sp; |
| sp = (unsigned long*)(*sp); |
| } |
| |
| // Prevent endless loops in case of invalid callstacks. |
| if (frame == MAX_CALLSTACK_DEPTH) { |
| st->print_cr("...(stopping after %d frames.", MAX_CALLSTACK_DEPTH); |
| } |
| |
| end_walk_callstack: |
| |
| st->print_cr("-----------------------"); |
| |
| cleanup: |
| |
| return; |
| |
| } |
| |
| |
| bool AixMisc::query_stack_bounds_for_current_thread(stackbounds_t* out) { |
| |
| // Information about this api can be found (a) in the pthread.h header and |
| // (b) in http://publib.boulder.ibm.com/infocenter/pseries/v5r3/index.jsp?topic=/com.ibm.aix.basetechref/doc/basetrf1/pthread_getthrds_np.htm |
| // |
| // The use of this API to find out the current stack is kind of undefined. |
| // But after a lot of tries and asking IBM about it, I concluded that it is safe |
| // enough for cases where I let the pthread library create its stacks. For cases |
| // where I create an own stack and pass this to pthread_create, it seems not to |
| // work (the returned stack size in that case is 0). |
| |
| pthread_t tid = pthread_self(); |
| struct __pthrdsinfo pinfo; |
| char dummy[1]; // Just needed to satisfy pthread_getthrds_np. |
| int dummy_size = sizeof(dummy); |
| |
| memset(&pinfo, 0, sizeof(pinfo)); |
| |
| const int rc = pthread_getthrds_np(&tid, PTHRDSINFO_QUERY_ALL, &pinfo, |
| sizeof(pinfo), dummy, &dummy_size); |
| |
| if (rc != 0) { |
| fprintf(stderr, "pthread_getthrds_np failed (%d)\n", rc); |
| fflush(stdout); |
| return false; |
| } |
| |
| // The following may happen when invoking pthread_getthrds_np on a pthread |
| // running on a user provided stack (when handing down a stack to pthread |
| // create, see pthread_attr_setstackaddr). |
| // Not sure what to do then. |
| if (pinfo.__pi_stackend == NULL || pinfo.__pi_stackaddr == NULL) { |
| fprintf(stderr, "pthread_getthrds_np - invalid values\n"); |
| fflush(stdout); |
| return false; |
| } |
| |
| // Note: we get three values from pthread_getthrds_np: |
| // __pi_stackaddr, __pi_stacksize, __pi_stackend |
| // |
| // high addr --------------------- base, high |
| // |
| // | pthread internal data, like ~2K |
| // | |
| // | --------------------- __pi_stackend (usually not page aligned, (xxxxF890)) |
| // | |
| // | |
| // | |
| // | |
| // | |
| // | |
| // | --------------------- (__pi_stackend - __pi_stacksize) |
| // | |
| // | padding to align the following AIX guard pages, if enabled. |
| // | |
| // V --------------------- __pi_stackaddr low, base - size |
| // |
| // low addr AIX guard pages, if enabled (AIXTHREAD_GUARDPAGES > 0) |
| // |
| |
| out->base = (address)pinfo.__pi_stackend; |
| address low = (address)pinfo.__pi_stackaddr; |
| out->size = out->base - low; |
| return true; |
| |
| } |
| |
| |
| |
| |