#include #include #include #include #include #include "debug.h" #include "unwind.h" #include "unwind-libdw.h" #include "machine.h" #include "thread.h" #include #include "event.h" #include "perf_regs.h" #include "callchain.h" static char *debuginfo_path; static const Dwfl_Callbacks offline_callbacks = { .find_debuginfo = dwfl_standard_find_debuginfo, .debuginfo_path = &debuginfo_path, .section_address = dwfl_offline_section_address, }; static int __report_module(struct addr_location *al, u64 ip, struct unwind_info *ui) { Dwfl_Module *mod; struct dso *dso = NULL; thread__find_addr_location(ui->thread, PERF_RECORD_MISC_USER, MAP__FUNCTION, ip, al); if (al->map) dso = al->map->dso; if (!dso) return 0; mod = dwfl_addrmodule(ui->dwfl, ip); if (!mod) mod = dwfl_report_elf(ui->dwfl, dso->short_name, dso->long_name, -1, al->map->start, false); return mod && dwfl_addrmodule(ui->dwfl, ip) == mod ? 0 : -1; } static int report_module(u64 ip, struct unwind_info *ui) { struct addr_location al; return __report_module(&al, ip, ui); } /* * Store all entries within entries array, * we will process it after we finish unwind. */ static int entry(u64 ip, struct unwind_info *ui) { struct unwind_entry *e = &ui->entries[ui->idx++]; struct addr_location al; if (__report_module(&al, ip, ui)) return -1; e->ip = al.addr; e->map = al.map; e->sym = al.sym; pr_debug("unwind: %s:ip = 0x%" PRIx64 " (0x%" PRIx64 ")\n", al.sym ? al.sym->name : "''", ip, al.map ? al.map->map_ip(al.map, ip) : (u64) 0); return 0; } static pid_t next_thread(Dwfl *dwfl, void *arg, void **thread_argp) { /* We want only single thread to be processed. */ if (*thread_argp != NULL) return 0; *thread_argp = arg; return dwfl_pid(dwfl); } static int access_dso_mem(struct unwind_info *ui, Dwarf_Addr addr, Dwarf_Word *data) { struct addr_location al; ssize_t size; thread__find_addr_map(ui->thread, PERF_RECORD_MISC_USER, MAP__FUNCTION, addr, &al); if (!al.map) { /* * We've seen cases (softice) where DWARF unwinder went * through non executable mmaps, which we need to lookup * in MAP__VARIABLE tree. */ thread__find_addr_map(ui->thread, PERF_RECORD_MISC_USER, MAP__VARIABLE, addr, &al); } if (!al.map) { pr_debug("unwind: no map for %lx\n", (unsigned long)addr); return -1; } if (!al.map->dso) return -1; size = dso__data_read_addr(al.map->dso, al.map, ui->machine, addr, (u8 *) data, sizeof(*data)); return !(size == sizeof(*data)); } static bool memory_read(Dwfl *dwfl __maybe_unused, Dwarf_Addr addr, Dwarf_Word *result, void *arg) { struct unwind_info *ui = arg; struct stack_dump *stack = &ui->sample->user_stack; u64 start, end; int offset; int ret; ret = perf_reg_value(&start, &ui->sample->user_regs, PERF_REG_SP); if (ret) return false; end = start + stack->size; /* Check overflow. */ if (addr + sizeof(Dwarf_Word) < addr) return false; if (addr < start || addr + sizeof(Dwarf_Word) > end) { ret = access_dso_mem(ui, addr, result); if (ret) { pr_debug("unwind: access_mem 0x%" PRIx64 " not inside range" " 0x%" PRIx64 "-0x%" PRIx64 "\n", addr, start, end); return false; } return true; } offset = addr - start; *result = *(Dwarf_Word *)&stack->data[offset]; pr_debug("unwind: access_mem addr 0x%" PRIx64 ", val %lx, offset %d\n", addr, (unsigned long)*result, offset); return true; } static const Dwfl_Thread_Callbacks callbacks = { .next_thread = next_thread, .memory_read = memory_read, .set_initial_registers = libdw__arch_set_initial_registers, }; static int frame_callback(Dwfl_Frame *state, void *arg) { struct unwind_info *ui = arg; Dwarf_Addr pc; if (!dwfl_frame_pc(state, &pc, NULL)) { pr_err("%s", dwfl_errmsg(-1)); return DWARF_CB_ABORT; } return entry(pc, ui) || !(--ui->max_stack) ? DWARF_CB_ABORT : DWARF_CB_OK; } int unwind__get_entries(unwind_entry_cb_t cb, void *arg, struct thread *thread, struct perf_sample *data, int max_stack) { struct unwind_info *ui, ui_buf = { .sample = data, .thread = thread, .machine = thread->mg->machine, .cb = cb, .arg = arg, .max_stack = max_stack, }; Dwarf_Word ip; int err = -EINVAL, i; if (!data->user_regs.regs) return -EINVAL; ui = zalloc(sizeof(ui_buf) + sizeof(ui_buf.entries[0]) * max_stack); if (!ui) return -ENOMEM; *ui = ui_buf; ui->dwfl = dwfl_begin(&offline_callbacks); if (!ui->dwfl) goto out; err = perf_reg_value(&ip, &data->user_regs, PERF_REG_IP); if (err) goto out; err = report_module(ip, ui); if (err) goto out; if (!dwfl_attach_state(ui->dwfl, EM_NONE, thread->tid, &callbacks, ui)) goto out; err = dwfl_getthread_frames(ui->dwfl, thread->tid, frame_callback, ui); if (err && !ui->max_stack) err = 0; /* * Display what we got based on the order setup. */ for (i = 0; i < ui->idx && !err; i++) { int j = i; if (callchain_param.order == ORDER_CALLER) j = ui->idx - i - 1; err = ui->entries[j].ip ? ui->cb(&ui->entries[j], ui->arg) : 0; } out: if (err) pr_debug("unwind: failed with '%s'\n", dwfl_errmsg(-1)); dwfl_end(ui->dwfl); free(ui); return 0; } firewire/amdtp-am824.c?h=nds-private-remove&id=54791b276b4000b307339f269d3bf7db877d536f'>54791b276b4000b307339f269d3bf7db877d536f (patch) tree1c2616bd373ce5ea28aac2a53e32f5b5834901ce /sound/firewire/amdtp-am824.c parent5d0e7705774dd412a465896d08d59a81a345c1e4 (diff)parent047487241ff59374fded8c477f21453681f5995c (diff)
Merge branch 'sparc64-non-resumable-user-error-recovery'
Liam R. Howlett says: ==================== sparc64: Recover from userspace non-resumable PIO & MEM errors A non-resumable error from userspace is able to cause a kernel panic or trap loop due to the setup and handling of the queued traps once in the kernel. This patch series addresses both of these issues. The queues are fixed by simply zeroing the memory before use. PIO errors from userspace will result in a SIGBUS being sent to the user process. The MEM errors form userspace will result in a SIGKILL and also cause the offending pages to be claimed so they are no longer used in future tasks. SIGKILL is used to ensure that the process does not try to coredump and result in an attempt to read the memory again from within kernel space. Although there is a HV call to scrub the memory (mem_scrub), there is no easy way to guarantee that the real memory address(es) are not used by other tasks. Clearing the error with mem_scrub would zero the memory and cause the other processes to proceed with bad data. The handling of other non-resumable errors remain unchanged and will cause a panic. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'sound/firewire/amdtp-am824.c')