Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 17 Oct 2002 04:53:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 17 Oct 2002 04:53:13 -0400 Received: from mx1.elte.hu ([157.181.1.137]:47792 "HELO mx1.elte.hu") by vger.kernel.org with SMTP id ; Thu, 17 Oct 2002 04:52:54 -0400 Date: Thu, 17 Oct 2002 11:11:21 +0200 (CEST) From: Ingo Molnar Reply-To: Ingo Molnar To: Linus Torvalds Cc: Alexander Viro , S Vamsikrishna , Mark Gross , Ulrich Drepper , , NPT library mailing list Subject: [patch] thread-aware coredumps, 2.5.43-C3 In-Reply-To: <200210081627.g98GRZP18285@unix-os.sc.intel.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 31441 Lines: 1095 the attached patch is the second iteration of thread-aware coredumps, against BK-curr. I think this patch is now ready for inclusion into mainline. Changes: - Ulrich Drepper has reviewed the data structures and checked actual coredumps via readelf - everything looks fine and according to the spec. - a serious bug has been fixed in the thread-state dumping code - it was still based on the 2.4 assumption that the task struct points to the kernel stack - it's task->thread_info in 2.5. This bug caused bogus register info to be filled in for threads. - properly wait for all threads that share the same MM to serialize with the coredumping thread. This is CLONE_VM based, not tied to CLONE_THREAD and/or signal semantics, ie. old-style (or different-style) threaded apps will be properly stopped as well. The locking might look a bit complex, but i wanted to keep the __exit_mm() overhead as low as possible. It's not quite trivial to get these bits right, because 'sharing the MM' is detached from signals semantics, so we cannot rely on broadcast-kill catching all threads. So zap_threads() iterates through every thread and zaps those which were left out. (There's a minimal race left in where a newly forked child might escape the attention of zap_threads() - this race is fixed by the OOM fixes in the mmap-speedup patch.) - fill_psinfo() is now called with the thread group leader, for the coredump to get 'process' state. - initialize the elf_thread_status structure with zeroes. the IA64 ELF bits are not included, yet, to reduce complexity of the patch. The patch has been tested on x86 UP and SMP. Ingo --- linux/arch/i386/kernel/i387.c.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/arch/i386/kernel/i387.c 2002-10-17 09:48:55.000000000 +0200 @@ -528,3 +528,40 @@ return fpvalid; } + +int dump_task_fpu(struct task_struct *tsk, struct user_i387_struct *fpu) +{ + int fpvalid = tsk->used_math; + + if (fpvalid) { + if (tsk == current) + unlazy_fpu(tsk); + if (cpu_has_fxsr) + copy_fpu_fxsave(tsk, fpu); + else + copy_fpu_fsave(tsk, fpu); + } + return fpvalid; +} + +int dump_task_extended_fpu(struct task_struct *tsk, struct user_fxsr_struct *fpu) +{ + int fpvalid = tsk->used_math && cpu_has_fxsr; + + if (fpvalid) { + if (tsk == current) + unlazy_fpu(tsk); + memcpy(fpu, &tsk->thread.i387.fxsave, sizeof(*fpu)); + } + return fpvalid; +} + + +#ifdef CONFIG_SMP +void dump_smp_unlazy_fpu(void) +{ + unlazy_fpu(current); + return; +} +#endif + --- linux/arch/i386/kernel/process.c.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/arch/i386/kernel/process.c 2002-10-17 10:17:22.000000000 +0200 @@ -19,6 +19,7 @@ #include #include #include +#include #include #include #include @@ -373,6 +374,25 @@ dump->u_fpvalid = dump_fpu (regs, &dump->i387); } +/* + * Capture the user space registers if the task is not running (in user space) + */ +int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs) +{ + struct pt_regs ptregs; + + ptregs = *(struct pt_regs *) + ((unsigned long)tsk->thread_info+THREAD_SIZE - sizeof(ptregs)); + ptregs.xcs &= 0xffff; + ptregs.xds &= 0xffff; + ptregs.xes &= 0xffff; + ptregs.xss &= 0xffff; + + elf_core_copy_regs(regs, &ptregs); + + return 1; +} + /* * This special macro can be used to load a debugging register */ --- linux/arch/ia64/kernel/process.c.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/arch/ia64/kernel/process.c 2002-10-17 09:48:55.000000000 +0200 @@ -382,6 +382,31 @@ void do_copy_regs (struct unw_frame_info *info, void *arg) { + do_copy_task_regs(current, info, arg); +} + +void +do_dump_fpu (struct unw_frame_info *info, void *arg) +{ + do_dump_task_fpu(current, info, arg); +} + +void +ia64_elf_core_copy_regs (struct pt_regs *pt, elf_gregset_t dst) +{ + unw_init_running(do_copy_regs, dst); +} + +int +dump_fpu (struct pt_regs *pt, elf_fpregset_t dst) +{ + unw_init_running(do_dump_fpu, dst); + return 1; /* f0-f31 are always valid so we always return 1 */ +} + +static void +do_copy_task_regs (struct task_struct *task, struct unw_frame_info *info, void *arg) +{ unsigned long mask, sp, nat_bits = 0, ip, ar_rnat, urbs_end, cfm; elf_greg_t *dst = arg; struct pt_regs *pt; @@ -396,12 +421,12 @@ unw_get_sp(info, &sp); pt = (struct pt_regs *) (sp + 16); - urbs_end = ia64_get_user_rbs_end(current, pt, &cfm); + urbs_end = ia64_get_user_rbs_end(task, pt, &cfm); - if (ia64_sync_user_rbs(current, info->sw, pt->ar_bspstore, urbs_end) < 0) + if (ia64_sync_user_rbs(task, info->sw, pt->ar_bspstore, urbs_end) < 0) return; - ia64_peek(current, info->sw, urbs_end, (long) ia64_rse_rnat_addr((long *) urbs_end), + ia64_peek(task, info->sw, urbs_end, (long) ia64_rse_rnat_addr((long *) urbs_end), &ar_rnat); /* @@ -450,7 +475,7 @@ } void -do_dump_fpu (struct unw_frame_info *info, void *arg) +do_dump_task_fpu (struct task_struct *task, struct unw_frame_info *info, void *arg) { elf_fpreg_t *dst = arg; int i; @@ -465,22 +490,41 @@ for (i = 2; i < 32; ++i) unw_get_fr(info, i, dst + i); - ia64_flush_fph(current); - if ((current->thread.flags & IA64_THREAD_FPH_VALID) != 0) - memcpy(dst + 32, current->thread.fph, 96*16); + ia64_flush_fph(task); + if ((task->thread.flags & IA64_THREAD_FPH_VALID) != 0) + memcpy(dst + 32, task->thread.fph, 96*16); } -void -ia64_elf_core_copy_regs (struct pt_regs *pt, elf_gregset_t dst) +int dump_task_regs(struct task_struct *task, elf_gregset_t *regs) { - unw_init_running(do_copy_regs, dst); + struct unw_frame_info tcore_info; + + if(current == task) { + unw_init_running(do_copy_regs, regs); + } + else { + memset(&tcore_info, 0, sizeof(tcore_info)); + unw_init_from_blocked_task(&tcore_info, task); + do_copy_task_regs(task, &tcore_info, regs); + } + + return 1; } -int -dump_fpu (struct pt_regs *pt, elf_fpregset_t dst) +int dump_task_fpu (struct task_struct *task, elf_fpregset_t *dst) { - unw_init_running(do_dump_fpu, dst); - return 1; /* f0-f31 are always valid so we always return 1 */ + struct unw_frame_info tcore_info; + + if(current == task) { + unw_init_running(do_dump_fpu, dst); + } + else { + memset(&tcore_info, 0, sizeof(tcore_info)); + unw_init_from_blocked_task(&tcore_info, task); + do_dump_task_fpu(task, &tcore_info, dst); + } + + return 1; } asmlinkage long --- linux/fs/binfmt_elf.c.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/fs/binfmt_elf.c 2002-10-17 10:56:25.000000000 +0200 @@ -30,6 +30,7 @@ #include #include #include +#include #include #include #include @@ -534,9 +535,6 @@ if (strcmp(elf_interpreter,"/usr/lib/libc.so.1") == 0 || strcmp(elf_interpreter,"/usr/lib/ld.so.1") == 0) ibcs2_interpreter = 1; -#if 0 - printk("Using ELF interpreter %s\n", elf_interpreter); -#endif SET_PERSONALITY(elf_ex, ibcs2_interpreter); @@ -759,16 +757,6 @@ padzero(elf_bss); -#if 0 - printk("(start_brk) %lx\n" , (long) current->mm->start_brk); - printk("(end_code) %lx\n" , (long) current->mm->end_code); - printk("(start_code) %lx\n" , (long) current->mm->start_code); - printk("(start_data) %lx\n" , (long) current->mm->start_data); - printk("(end_data) %lx\n" , (long) current->mm->end_data); - printk("(start_stack) %lx\n" , (long) current->mm->start_stack); - printk("(brk) %lx\n" , (long) current->mm->brk); -#endif - if (current->personality & MMAP_PAGE_ZERO) { /* Why this, you ask??? Well SVr4 maps page 0 as read-only, and some applications "depend" upon this behavior. @@ -967,26 +955,6 @@ return sz; } -/* #define DEBUG */ - -#ifdef DEBUG -static void dump_regs(const char *str, elf_greg_t *r) -{ - int i; - static const char *regs[] = { "ebx", "ecx", "edx", "esi", "edi", "ebp", - "eax", "ds", "es", "fs", "gs", - "orig_eax", "eip", "cs", - "efl", "uesp", "ss"}; - printk("Registers: %s\n", str); - - for(i = 0; i < ELF_NGREG; i++) - { - unsigned long val = r[i]; - printk(" %-2d %-5s=%08lx %lu\n", i, regs[i], val, val); - } -} -#endif - #define DUMP_WRITE(addr, nr) \ do { if (!dump_write(file, (addr), (nr))) return 0; } while(0) #define DUMP_SEEK(off) \ @@ -1018,6 +986,164 @@ #define DUMP_SEEK(off) \ if (!dump_seek(file, (off))) \ goto end_coredump; + +static inline void fill_elf_header(struct elfhdr *elf, int segs) +{ + memcpy(elf->e_ident, ELFMAG, SELFMAG); + elf->e_ident[EI_CLASS] = ELF_CLASS; + elf->e_ident[EI_DATA] = ELF_DATA; + elf->e_ident[EI_VERSION] = EV_CURRENT; + memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD); + + elf->e_type = ET_CORE; + elf->e_machine = ELF_ARCH; + elf->e_version = EV_CURRENT; + elf->e_entry = 0; + elf->e_phoff = sizeof(struct elfhdr); + elf->e_shoff = 0; + elf->e_flags = 0; + elf->e_ehsize = sizeof(struct elfhdr); + elf->e_phentsize = sizeof(struct elf_phdr); + elf->e_phnum = segs; + elf->e_shentsize = 0; + elf->e_shnum = 0; + elf->e_shstrndx = 0; + return; +} + +static inline void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, off_t offset) +{ + phdr->p_type = PT_NOTE; + phdr->p_offset = offset; + phdr->p_vaddr = 0; + phdr->p_paddr = 0; + phdr->p_filesz = sz; + phdr->p_memsz = 0; + phdr->p_flags = 0; + phdr->p_align = 0; + return; +} + +static inline void fill_note(struct memelfnote *note, const char *name, int type, + unsigned int sz, void *data) +{ + note->name = name; + note->type = type; + note->datasz = sz; + note->data = data; + return; +} + +/* + * fill up all the fields in prstatus from the given task struct, except registers + * which need to be filled up seperately. + */ +static inline void fill_prstatus(struct elf_prstatus *prstatus, struct task_struct *p, long signr) +{ + prstatus->pr_info.si_signo = prstatus->pr_cursig = signr; + prstatus->pr_sigpend = p->pending.signal.sig[0]; + prstatus->pr_sighold = p->blocked.sig[0]; + prstatus->pr_pid = p->pid; + prstatus->pr_ppid = p->parent->pid; + prstatus->pr_pgrp = p->pgrp; + prstatus->pr_sid = p->session; + jiffies_to_timeval(p->utime, &prstatus->pr_utime); + jiffies_to_timeval(p->stime, &prstatus->pr_stime); + jiffies_to_timeval(p->cutime, &prstatus->pr_cutime); + jiffies_to_timeval(p->cstime, &prstatus->pr_cstime); +} + +static inline void fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p) +{ + int i, len; + + /* first copy the parameters from user space */ + memset(psinfo, 0, sizeof(struct elf_prpsinfo)); + + len = p->mm->arg_end - p->mm->arg_start; + if (len >= ELF_PRARGSZ) + len = ELF_PRARGSZ-1; + copy_from_user(&psinfo->pr_psargs, + (const char *)p->mm->arg_start, len); + for(i = 0; i < len; i++) + if (psinfo->pr_psargs[i] == 0) + psinfo->pr_psargs[i] = ' '; + psinfo->pr_psargs[len] = 0; + + psinfo->pr_pid = p->pid; + psinfo->pr_ppid = p->parent->pid; + psinfo->pr_pgrp = p->pgrp; + psinfo->pr_sid = p->session; + + i = p->state ? ffz(~p->state) + 1 : 0; + psinfo->pr_state = i; + psinfo->pr_sname = (i < 0 || i > 5) ? '.' : "RSDZTD"[i]; + psinfo->pr_zomb = psinfo->pr_sname == 'Z'; + psinfo->pr_nice = task_nice(p); + psinfo->pr_flag = p->flags; + psinfo->pr_uid = NEW_TO_OLD_UID(p->uid); + psinfo->pr_gid = NEW_TO_OLD_GID(p->gid); + strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname)); + + return; +} + +/* Here is the structure in which status of each thread is captured. */ +struct elf_thread_status +{ + struct list_head list; + struct elf_prstatus prstatus; /* NT_PRSTATUS */ + elf_fpregset_t fpu; /* NT_PRFPREG */ +#ifdef ELF_CORE_COPY_XFPREGS + elf_fpxregset_t xfpu; /* NT_PRXFPREG */ +#endif + struct memelfnote notes[3]; + int num_notes; +}; + +/* + * In order to add the specific thread information for the elf file format, + * we need to keep a linked list of every threads pr_status and then + * create a single section for them in the final core file. + */ +static int elf_dump_thread_status(long signr, struct task_struct * p, struct list_head * thread_list) +{ + + struct elf_thread_status *t; + int sz = 0; + + t = kmalloc(sizeof(*t), GFP_ATOMIC); + if (!t) + return 0; + memset(t, 0, sizeof(*t)); + + INIT_LIST_HEAD(&t->list); + t->num_notes = 0; + + fill_prstatus(&t->prstatus, p, signr); + elf_core_copy_task_regs(p, &t->prstatus.pr_reg); + + fill_note(&t->notes[0], "CORE", NT_PRSTATUS, sizeof(t->prstatus), &(t->prstatus)); + t->num_notes++; + sz += notesize(&t->notes[0]); + + if ((t->prstatus.pr_fpvalid = elf_core_copy_task_fpregs(p, &t->fpu))) { + fill_note(&t->notes[1], "CORE", NT_PRFPREG, sizeof(t->fpu), &(t->fpu)); + t->num_notes++; + sz += notesize(&t->notes[1]); + } + +#ifdef ELF_CORE_COPY_XFPREGS + if (elf_core_copy_task_xfpregs(p, &t->xfpu)) { + fill_note(&t->notes[2], "LINUX", NT_PRXFPREG, sizeof(t->xfpu), &t->xfpu); + t->num_notes++; + sz += notesize(&t->notes[2]); + } +#endif + list_add(&t->list, thread_list); + return sz; +} + /* * Actual dumper * @@ -1036,74 +1162,56 @@ struct elfhdr elf; off_t offset = 0, dataoff; unsigned long limit = current->rlim[RLIMIT_CORE].rlim_cur; - int numnote = 4; - struct memelfnote notes[4]; + int numnote = 5; + struct memelfnote notes[5]; struct elf_prstatus prstatus; /* NT_PRSTATUS */ - elf_fpregset_t fpu; /* NT_PRFPREG */ struct elf_prpsinfo psinfo; /* NT_PRPSINFO */ - - /* first copy the parameters from user space */ - memset(&psinfo, 0, sizeof(psinfo)); - { - int i, len; - - len = current->mm->arg_end - current->mm->arg_start; - if (len >= ELF_PRARGSZ) - len = ELF_PRARGSZ-1; - copy_from_user(&psinfo.pr_psargs, - (const char *)current->mm->arg_start, len); - for(i = 0; i < len; i++) - if (psinfo.pr_psargs[i] == 0) - psinfo.pr_psargs[i] = ' '; - psinfo.pr_psargs[len] = 0; - - } - - memset(&prstatus, 0, sizeof(prstatus)); - /* - * This transfers the registers from regs into the standard - * coredump arrangement, whatever that is. + struct task_struct *g, *p; + LIST_HEAD(thread_list); + struct list_head *t; + elf_fpregset_t fpu; +#ifdef ELF_CORE_COPY_XFPREGS + elf_fpxregset_t xfpu; +#endif + int thread_status_size = 0; + + /* We no longer stop all vm operations + * + * This because those proceses that could possibly + * change map_count or the mmap / vma pages are now blocked in do_exit on current finishing + * this core dump. + * + * Only ptrace can touch these memory addresses, but it doesn't change + * the map_count or the pages allocated. So no possibility of crashing exists while dumping + * the mm->vm_next areas to the core file. + * */ -#ifdef ELF_CORE_COPY_REGS - ELF_CORE_COPY_REGS(prstatus.pr_reg, regs) -#else - if (sizeof(elf_gregset_t) != sizeof(struct pt_regs)) - { - printk("sizeof(elf_gregset_t) (%ld) != sizeof(struct pt_regs) (%ld)\n", - (long)sizeof(elf_gregset_t), (long)sizeof(struct pt_regs)); + + /* capture the status of all other threads */ + if (signr) { + read_lock(&tasklist_lock); + do_each_thread(g,p) + if (current->mm == p->mm && current != p) { + int sz = elf_dump_thread_status(signr, p, &thread_list); + if (!sz) { + read_unlock(&tasklist_lock); + goto cleanup; + } else + thread_status_size += sz; + } + while_each_thread(g,p); + read_unlock(&tasklist_lock); } - else - *(struct pt_regs *)&prstatus.pr_reg = *regs; -#endif - /* now stop all vm operations */ - down_write(¤t->mm->mmap_sem); + /* now collect the dump for the current */ + memset(&prstatus, 0, sizeof(prstatus)); + fill_prstatus(&prstatus, current, signr); + elf_core_copy_regs(&prstatus.pr_reg, regs); + segs = current->mm->map_count; -#ifdef DEBUG - printk("elf_core_dump: %d segs %lu limit\n", segs, limit); -#endif - /* Set up header */ - memcpy(elf.e_ident, ELFMAG, SELFMAG); - elf.e_ident[EI_CLASS] = ELF_CLASS; - elf.e_ident[EI_DATA] = ELF_DATA; - elf.e_ident[EI_VERSION] = EV_CURRENT; - memset(elf.e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD); - - elf.e_type = ET_CORE; - elf.e_machine = ELF_ARCH; - elf.e_version = EV_CURRENT; - elf.e_entry = 0; - elf.e_phoff = sizeof(elf); - elf.e_shoff = 0; - elf.e_flags = 0; - elf.e_ehsize = sizeof(elf); - elf.e_phentsize = sizeof(struct elf_phdr); - elf.e_phnum = segs+1; /* Include notes */ - elf.e_shentsize = 0; - elf.e_shnum = 0; - elf.e_shstrndx = 0; + fill_elf_header(&elf, segs+1); /* including notes section*/ fs = get_fs(); set_fs(KERNEL_DS); @@ -1120,60 +1228,27 @@ * with info from their /proc. */ - notes[0].name = "CORE"; - notes[0].type = NT_PRSTATUS; - notes[0].datasz = sizeof(prstatus); - notes[0].data = &prstatus; - prstatus.pr_info.si_signo = prstatus.pr_cursig = signr; - prstatus.pr_sigpend = current->pending.signal.sig[0]; - prstatus.pr_sighold = current->blocked.sig[0]; - psinfo.pr_pid = prstatus.pr_pid = current->pid; - psinfo.pr_ppid = prstatus.pr_ppid = current->parent->pid; - psinfo.pr_pgrp = prstatus.pr_pgrp = current->pgrp; - psinfo.pr_sid = prstatus.pr_sid = current->session; - jiffies_to_timeval(current->utime, &prstatus.pr_utime); - jiffies_to_timeval(current->stime, &prstatus.pr_stime); - jiffies_to_timeval(current->cutime, &prstatus.pr_cutime); - jiffies_to_timeval(current->cstime, &prstatus.pr_cstime); - -#ifdef DEBUG - dump_regs("Passed in regs", (elf_greg_t *)regs); - dump_regs("prstatus regs", (elf_greg_t *)&prstatus.pr_reg); -#endif - - notes[1].name = "CORE"; - notes[1].type = NT_PRPSINFO; - notes[1].datasz = sizeof(psinfo); - notes[1].data = &psinfo; - i = current->state ? ffz(~current->state) + 1 : 0; - psinfo.pr_state = i; - psinfo.pr_sname = (i < 0 || i > 5) ? '.' : "RSDZTD"[i]; - psinfo.pr_zomb = psinfo.pr_sname == 'Z'; - psinfo.pr_nice = task_nice(current); - psinfo.pr_flag = current->flags; - psinfo.pr_uid = NEW_TO_OLD_UID(current->uid); - psinfo.pr_gid = NEW_TO_OLD_GID(current->gid); - strncpy(psinfo.pr_fname, current->comm, sizeof(psinfo.pr_fname)); - - notes[2].name = "CORE"; - notes[2].type = NT_TASKSTRUCT; - notes[2].datasz = sizeof(*current); - notes[2].data = current; - - /* Try to dump the FPU. */ - prstatus.pr_fpvalid = dump_fpu (regs, &fpu); - if (!prstatus.pr_fpvalid) - { - numnote--; - } - else - { - notes[3].name = "CORE"; - notes[3].type = NT_PRFPREG; - notes[3].datasz = sizeof(fpu); - notes[3].data = &fpu; - } + fill_note(¬es[0], "CORE", NT_PRSTATUS, sizeof(prstatus), &prstatus); + + fill_psinfo(&psinfo, current->group_leader); + fill_note(¬es[1], "CORE", NT_PRPSINFO, sizeof(psinfo), &psinfo); + fill_note(¬es[2], "CORE", NT_TASKSTRUCT, sizeof(*current), current); + + /* Try to dump the FPU. */ + if ((prstatus.pr_fpvalid = elf_core_copy_task_fpregs(current, &fpu))) + fill_note(¬es[3], "CORE", NT_PRFPREG, sizeof(fpu), &fpu); + else + --numnote; +#ifdef ELF_CORE_COPY_XFPREGS + if (elf_core_copy_task_xfpregs(current, &xfpu)) + fill_note(¬es[4], "LINUX", NT_PRXFPREG, sizeof(xfpu), &xfpu); + else + --numnote; +#else + numnote --; +#endif + /* Write notes phdr entry */ { struct elf_phdr phdr; @@ -1181,17 +1256,11 @@ for(i = 0; i < numnote; i++) sz += notesize(¬es[i]); + + sz += thread_status_size; - phdr.p_type = PT_NOTE; - phdr.p_offset = offset; - phdr.p_vaddr = 0; - phdr.p_paddr = 0; - phdr.p_filesz = sz; - phdr.p_memsz = 0; - phdr.p_flags = 0; - phdr.p_align = 0; - - offset += phdr.p_filesz; + fill_elf_note_phdr(&phdr, sz, offset); + offset += sz; DUMP_WRITE(&phdr, sizeof(phdr)); } @@ -1220,10 +1289,19 @@ DUMP_WRITE(&phdr, sizeof(phdr)); } + /* write out the notes section */ for(i = 0; i < numnote; i++) if (!writenote(¬es[i], file)) goto end_coredump; + /* write out the thread status notes section */ + list_for_each(t, &thread_list) { + struct elf_thread_status *tmp = list_entry(t, struct elf_thread_status, list); + for (i = 0; i < tmp->num_notes; i++) + if (!writenote(&tmp->notes[i], file)) + goto end_coredump; + } + DUMP_SEEK(dataoff); for(vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) { @@ -1232,10 +1310,6 @@ if (!maydump(vma)) continue; -#ifdef DEBUG - printk("elf_core_dump: writing %08lx-%08lx\n", vma->vm_start, vma->vm_end); -#endif - for (addr = vma->vm_start; addr < vma->vm_end; addr += PAGE_SIZE) { @@ -1267,11 +1341,19 @@ (off_t) file->f_pos, offset); } - end_coredump: +end_coredump: set_fs(fs); - up_write(¤t->mm->mmap_sem); + +cleanup: + while(!list_empty(&thread_list)) { + struct list_head *tmp = thread_list.next; + list_del(tmp); + kfree(list_entry(tmp, struct elf_thread_status, list)); + } + return has_dumped; } + #endif /* USE_ELF_CORE_DUMP */ static int __init init_elf_binfmt(void) --- linux/fs/exec.c.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/fs/exec.c 2002-10-17 10:18:17.000000000 +0200 @@ -1209,6 +1209,35 @@ *out_ptr = 0; } +static void zap_threads (struct mm_struct *mm) +{ + struct task_struct *g, *p; + + /* give other threads a chance to run: */ + yield(); + + read_lock(&tasklist_lock); + do_each_thread(g,p) + if (mm == p->mm && !p->core_waiter) + force_sig_specific(SIGKILL, p); + while_each_thread(g,p); + read_unlock(&tasklist_lock); +} + +static void coredump_wait(struct mm_struct *mm) +{ + DECLARE_WAITQUEUE(wait, current); + + atomic_inc(&mm->core_waiters); + add_wait_queue(&mm->core_wait, &wait); + zap_threads(mm); + current->state = TASK_UNINTERRUPTIBLE; + if (atomic_read(&mm->core_waiters) != atomic_read(&mm->mm_users)) + schedule(); + else + current->state = TASK_RUNNING; +} + int do_coredump(long signr, struct pt_regs * regs) { struct linux_binfmt * binfmt; @@ -1224,13 +1253,16 @@ if (!current->mm->dumpable) goto fail; current->mm->dumpable = 0; + if (down_trylock(¤t->mm->core_sem)) + BUG(); + coredump_wait(current->mm); if (current->rlim[RLIMIT_CORE].rlim_cur < binfmt->min_coredump) - goto fail; + goto fail_unlock; format_corename(corename, core_pattern, signr); file = filp_open(corename, O_CREAT | 2 | O_NOFOLLOW, 0600); if (IS_ERR(file)) - goto fail; + goto fail_unlock; inode = file->f_dentry->d_inode; if (inode->i_nlink > 1) goto close_fail; /* multiple links - don't dump */ @@ -1250,6 +1282,8 @@ close_fail: filp_close(file, NULL); +fail_unlock: + up(¤t->mm->core_sem); fail: unlock_kernel(); return retval; --- linux/include/linux/elf.h.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/include/linux/elf.h 2002-10-17 09:48:55.000000000 +0200 @@ -1,6 +1,7 @@ #ifndef _LINUX_ELF_H #define _LINUX_ELF_H +#include #include #include @@ -575,7 +576,8 @@ #define NT_PRFPREG 2 #define NT_PRPSINFO 3 #define NT_TASKSTRUCT 4 -#define NT_PRFPXREG 20 +#define NT_PRXFPREG 0x46e62b7f /* copied from gdb5.1/include/elf/common.h */ + /* Note header in a PT_NOTE section */ typedef struct elf32_note { --- linux/include/linux/elfcore.h.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/include/linux/elfcore.h 2002-10-17 09:48:55.000000000 +0200 @@ -85,4 +85,45 @@ #define PRARGSZ ELF_PRARGSZ #endif +#ifdef __KERNEL__ +static inline void elf_core_copy_regs(elf_gregset_t *elfregs, struct pt_regs *regs) +{ +#ifdef ELF_CORE_COPY_REGS + ELF_CORE_COPY_REGS((*elfregs), regs) +#else + BUG_ON(sizeof(*elfregs) != sizeof(*regs)); + *(struct pt_regs *)elfregs = *regs; +#endif +} + +static inline int elf_core_copy_task_regs(struct task_struct *t, elf_gregset_t* elfregs) +{ +#ifdef ELF_CORE_COPY_TASK_REGS + + return ELF_CORE_COPY_TASK_REGS(t, elfregs); +#endif + return 0; +} + +extern int dump_fpu (struct pt_regs *, elf_fpregset_t *); + +static inline int elf_core_copy_task_fpregs(struct task_struct *t, elf_fpregset_t *fpu) +{ +#ifdef ELF_CORE_COPY_FPREGS + return ELF_CORE_COPY_FPREGS(t, fpu); +#else + return dump_fpu(NULL, fpu); +#endif +} + +#ifdef ELF_CORE_COPY_XFPREGS +static inline int elf_core_copy_task_xfpregs(struct task_struct *t, elf_fpxregset_t *xfpu) +{ + return ELF_CORE_COPY_XFPREGS(t, xfpu); +} +#endif + +#endif /* __KERNEL__ */ + + #endif /* _LINUX_ELFCORE_H */ --- linux/include/linux/sched.h.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/include/linux/sched.h 2002-10-17 09:48:55.000000000 +0200 @@ -208,6 +208,11 @@ /* Architecture-specific MM context */ mm_context_t context; + /* coredumping support */ + struct semaphore core_sem; + atomic_t core_waiters; + wait_queue_head_t core_wait; + /* aio bits */ rwlock_t ioctx_list_lock; struct kioctx *ioctx_list; @@ -401,6 +406,8 @@ void *journal_info; struct dentry *proc_dentry; struct backing_dev_info *backing_dev_info; +/* threaded coredumping support */ + int core_waiter; }; extern void __put_task_struct(struct task_struct *tsk); @@ -540,6 +547,7 @@ extern void notify_parent(struct task_struct *, int); extern void do_notify_parent(struct task_struct *, int); extern void force_sig(int, struct task_struct *); +extern void force_sig_specific(int, struct task_struct *); extern int send_sig(int, struct task_struct *, int); extern int __broadcast_thread_group(struct task_struct *p, int sig); extern int kill_pg(pid_t, int, int); --- linux/include/asm-ia64/elf.h.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/include/asm-ia64/elf.h 2002-10-17 09:48:55.000000000 +0200 @@ -65,12 +65,16 @@ #define ELF_NGREG 128 /* we really need just 72 but let's leave some headroom... */ #define ELF_NFPREG 128 /* f0 and f1 could be omitted, but so what... */ +typedef unsigned long elf_fpxregset_t; + typedef unsigned long elf_greg_t; typedef elf_greg_t elf_gregset_t[ELF_NGREG]; typedef struct ia64_fpreg elf_fpreg_t; typedef elf_fpreg_t elf_fpregset_t[ELF_NFPREG]; + + struct pt_regs; /* forward declaration... */ extern void ia64_elf_core_copy_regs (struct pt_regs *src, elf_gregset_t dst); #define ELF_CORE_COPY_REGS(_dest,_regs) ia64_elf_core_copy_regs(_regs, _dest); @@ -88,6 +92,14 @@ struct elf64_hdr; extern void ia64_set_personality (struct elf64_hdr *elf_ex, int ibcs2_interpreter); #define SET_PERSONALITY(ex, ibcs2) ia64_set_personality(&(ex), ibcs2) + +extern int dump_task_regs(struct task_struct *, elf_gregset_t *); +extern int dump_task_fpu (struct task_struct *, elf_fpregset_t *); + +#define ELF_CORE_COPY_TASK_REGS(tsk, elf_gregs) dump_task_regs(tsk, elf_gregs) +#define ELF_CORE_COPY_FPREGS(tsk, elf_fpregs) dump_task_fpu(tsk, elf_fpregs) + + #endif #endif /* _ASM_IA64_ELF_H */ --- linux/include/asm-i386/elf.h.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/include/asm-i386/elf.h 2002-10-17 09:48:55.000000000 +0200 @@ -7,6 +7,7 @@ #include #include +#include #include @@ -59,6 +60,9 @@ /* Wow, the "main" arch needs arch dependent functions too.. :) */ +#define savesegment(seg,value) \ + asm volatile("movl %%" #seg ",%0":"=m" (*(int *)&(value))) + /* regs is struct pt_regs, pr_reg is elf_gregset_t (which is now struct_user_regs, they are different) */ @@ -72,9 +76,8 @@ pr_reg[6] = regs->eax; \ pr_reg[7] = regs->xds; \ pr_reg[8] = regs->xes; \ - /* fake once used fs and gs selectors? */ \ - pr_reg[9] = regs->xds; /* was fs and __fs */ \ - pr_reg[10] = regs->xds; /* was gs and __gs */ \ + savesegment(fs,pr_reg[9]); \ + savesegment(gs,pr_reg[10]); \ pr_reg[11] = regs->orig_eax; \ pr_reg[12] = regs->eip; \ pr_reg[13] = regs->xcs; \ @@ -99,6 +102,20 @@ #ifdef __KERNEL__ #define SET_PERSONALITY(ex, ibcs2) set_personality((ibcs2)?PER_SVR4:PER_LINUX) + +extern int dump_task_regs (struct task_struct *, elf_gregset_t *); +extern int dump_task_fpu (struct task_struct *, elf_fpregset_t *); +extern int dump_task_extended_fpu (struct task_struct *, struct user_fxsr_struct *); + +#define ELF_CORE_COPY_TASK_REGS(tsk, elf_regs) dump_task_regs(tsk, elf_regs) +#define ELF_CORE_COPY_FPREGS(tsk, elf_fpregs) dump_task_fpu(tsk, elf_fpregs) +#define ELF_CORE_COPY_XFPREGS(tsk, elf_xfpregs) dump_task_extended_fpu(tsk, elf_xfpregs) + +#ifdef CONFIG_SMP +extern void dump_smp_unlazy_fpu(void); +#define ELF_CORE_SYNC dump_smp_unlazy_fpu +#endif + #endif #endif --- linux/kernel/exit.c.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/kernel/exit.c 2002-10-17 09:48:55.000000000 +0200 @@ -416,19 +416,31 @@ */ static inline void __exit_mm(struct task_struct * tsk) { - struct mm_struct * mm = tsk->mm; + struct mm_struct *mm = tsk->mm; mm_release(); - if (mm) { - atomic_inc(&mm->mm_count); - if (mm != tsk->active_mm) BUG(); - /* more a memory barrier than a real lock */ - task_lock(tsk); - tsk->mm = NULL; - enter_lazy_tlb(mm, current, smp_processor_id()); - task_unlock(tsk); - mmput(mm); + if (!mm) + return; + /* + * Serialize with any possible pending coredump: + */ + if (!mm->dumpable) { + current->core_waiter = 1; + atomic_inc(&mm->core_waiters); + if (atomic_read(&mm->core_waiters) ==atomic_read(&mm->mm_users)) + wake_up(&mm->core_wait); + down(&mm->core_sem); + up(&mm->core_sem); + atomic_dec(&mm->core_waiters); } + atomic_inc(&mm->mm_count); + if (mm != tsk->active_mm) BUG(); + /* more a memory barrier than a real lock */ + task_lock(tsk); + tsk->mm = NULL; + enter_lazy_tlb(mm, current, smp_processor_id()); + task_unlock(tsk); + mmput(mm); } void exit_mm(struct task_struct *tsk) --- linux/kernel/fork.c.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/kernel/fork.c 2002-10-17 09:48:55.000000000 +0200 @@ -305,6 +305,9 @@ atomic_set(&mm->mm_users, 1); atomic_set(&mm->mm_count, 1); init_rwsem(&mm->mmap_sem); + init_MUTEX(&mm->core_sem); + init_waitqueue_head(&mm->core_wait); + atomic_set(&mm->core_waiters, 0); mm->page_table_lock = SPIN_LOCK_UNLOCKED; mm->ioctx_list_lock = RW_LOCK_UNLOCKED; mm->default_kioctx = (struct kioctx)INIT_KIOCTX(mm->default_kioctx, *mm); @@ -771,6 +774,8 @@ INIT_LIST_HEAD(&p->local_pages); + p->core_waiter = 0; + retval = -ENOMEM; if (security_ops->task_alloc_security(p)) goto bad_fork_cleanup; --- linux/kernel/signal.c.orig 2002-10-17 09:48:47.000000000 +0200 +++ linux/kernel/signal.c 2002-10-17 09:48:55.000000000 +0200 @@ -768,7 +768,7 @@ } static int -specific_force_sig_info(int sig, struct task_struct *t) +__specific_force_sig_info(int sig, struct task_struct *t) { if (!t->sig) return -ESRCH; @@ -781,6 +781,20 @@ return specific_send_sig_info(sig, (void *)2, t, 0); } +void +force_sig_specific(int sig, struct task_struct *t) +{ + unsigned long int flags; + + spin_lock_irqsave(&t->sig->siglock, flags); + if (t->sig->action[sig-1].sa.sa_handler == SIG_IGN) + t->sig->action[sig-1].sa.sa_handler = SIG_DFL; + sigdelset(&t->blocked, sig); + recalc_sigpending_tsk(t); + specific_send_sig_info(sig, (void *)2, t, 0); + spin_unlock_irqrestore(&t->sig->siglock, flags); +} + #define can_take_signal(p, sig) \ (((unsigned long) p->sig->action[sig-1].sa.sa_handler > 1) && \ !sigismember(&p->blocked, sig) && (task_curr(p) || !signal_pending(p))) @@ -846,7 +860,7 @@ int err = 0; for_each_task_pid(p->tgid, PIDTYPE_TGID, tmp, l, pid) - err = specific_force_sig_info(sig, tmp); + err = __specific_force_sig_info(sig, tmp); return err; } - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/