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![Greg Kroah-Hartman](/assets/img/avatar_default.png)
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
658 lines
16 KiB
C
658 lines
16 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* fs/proc/kcore.c kernel ELF core dumper
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*
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* Modelled on fs/exec.c:aout_core_dump()
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* Jeremy Fitzhardinge <jeremy@sw.oz.au>
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* ELF version written by David Howells <David.Howells@nexor.co.uk>
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* Modified and incorporated into 2.3.x by Tigran Aivazian <tigran@veritas.com>
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* Support to dump vmalloc'd areas (ELF only), Tigran Aivazian <tigran@veritas.com>
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* Safe accesses to vmalloc/direct-mapped discontiguous areas, Kanoj Sarcar <kanoj@sgi.com>
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*/
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#include <linux/mm.h>
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#include <linux/proc_fs.h>
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#include <linux/kcore.h>
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#include <linux/user.h>
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#include <linux/capability.h>
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#include <linux/elf.h>
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#include <linux/elfcore.h>
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#include <linux/notifier.h>
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#include <linux/vmalloc.h>
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#include <linux/highmem.h>
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#include <linux/printk.h>
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#include <linux/bootmem.h>
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/uaccess.h>
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#include <asm/io.h>
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#include <linux/list.h>
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#include <linux/ioport.h>
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#include <linux/memory.h>
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#include <linux/sched/task.h>
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#include <asm/sections.h>
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#include "internal.h"
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#define CORE_STR "CORE"
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#ifndef ELF_CORE_EFLAGS
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#define ELF_CORE_EFLAGS 0
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#endif
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static struct proc_dir_entry *proc_root_kcore;
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#ifndef kc_vaddr_to_offset
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#define kc_vaddr_to_offset(v) ((v) - PAGE_OFFSET)
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#endif
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#ifndef kc_offset_to_vaddr
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#define kc_offset_to_vaddr(o) ((o) + PAGE_OFFSET)
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#endif
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/* An ELF note in memory */
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struct memelfnote
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{
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const char *name;
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int type;
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unsigned int datasz;
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void *data;
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};
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static LIST_HEAD(kclist_head);
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static DEFINE_RWLOCK(kclist_lock);
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static int kcore_need_update = 1;
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void
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kclist_add(struct kcore_list *new, void *addr, size_t size, int type)
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{
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new->addr = (unsigned long)addr;
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new->size = size;
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new->type = type;
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write_lock(&kclist_lock);
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list_add_tail(&new->list, &kclist_head);
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write_unlock(&kclist_lock);
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}
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static size_t get_kcore_size(int *nphdr, size_t *elf_buflen)
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{
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size_t try, size;
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struct kcore_list *m;
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*nphdr = 1; /* PT_NOTE */
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size = 0;
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list_for_each_entry(m, &kclist_head, list) {
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try = kc_vaddr_to_offset((size_t)m->addr + m->size);
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if (try > size)
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size = try;
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*nphdr = *nphdr + 1;
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}
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*elf_buflen = sizeof(struct elfhdr) +
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(*nphdr + 2)*sizeof(struct elf_phdr) +
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3 * ((sizeof(struct elf_note)) +
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roundup(sizeof(CORE_STR), 4)) +
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roundup(sizeof(struct elf_prstatus), 4) +
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roundup(sizeof(struct elf_prpsinfo), 4) +
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roundup(arch_task_struct_size, 4);
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*elf_buflen = PAGE_ALIGN(*elf_buflen);
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return size + *elf_buflen;
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}
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static void free_kclist_ents(struct list_head *head)
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{
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struct kcore_list *tmp, *pos;
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list_for_each_entry_safe(pos, tmp, head, list) {
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list_del(&pos->list);
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kfree(pos);
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}
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}
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/*
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* Replace all KCORE_RAM/KCORE_VMEMMAP information with passed list.
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*/
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static void __kcore_update_ram(struct list_head *list)
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{
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int nphdr;
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size_t size;
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struct kcore_list *tmp, *pos;
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LIST_HEAD(garbage);
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write_lock(&kclist_lock);
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if (kcore_need_update) {
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list_for_each_entry_safe(pos, tmp, &kclist_head, list) {
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if (pos->type == KCORE_RAM
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|| pos->type == KCORE_VMEMMAP)
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list_move(&pos->list, &garbage);
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}
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list_splice_tail(list, &kclist_head);
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} else
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list_splice(list, &garbage);
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kcore_need_update = 0;
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proc_root_kcore->size = get_kcore_size(&nphdr, &size);
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write_unlock(&kclist_lock);
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free_kclist_ents(&garbage);
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}
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#ifdef CONFIG_HIGHMEM
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/*
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* If no highmem, we can assume [0...max_low_pfn) continuous range of memory
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* because memory hole is not as big as !HIGHMEM case.
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* (HIGHMEM is special because part of memory is _invisible_ from the kernel.)
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*/
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static int kcore_update_ram(void)
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{
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LIST_HEAD(head);
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struct kcore_list *ent;
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int ret = 0;
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ent = kmalloc(sizeof(*ent), GFP_KERNEL);
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if (!ent)
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return -ENOMEM;
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ent->addr = (unsigned long)__va(0);
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ent->size = max_low_pfn << PAGE_SHIFT;
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ent->type = KCORE_RAM;
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list_add(&ent->list, &head);
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__kcore_update_ram(&head);
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return ret;
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}
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#else /* !CONFIG_HIGHMEM */
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#ifdef CONFIG_SPARSEMEM_VMEMMAP
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/* calculate vmemmap's address from given system ram pfn and register it */
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static int
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get_sparsemem_vmemmap_info(struct kcore_list *ent, struct list_head *head)
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{
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unsigned long pfn = __pa(ent->addr) >> PAGE_SHIFT;
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unsigned long nr_pages = ent->size >> PAGE_SHIFT;
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unsigned long start, end;
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struct kcore_list *vmm, *tmp;
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start = ((unsigned long)pfn_to_page(pfn)) & PAGE_MASK;
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end = ((unsigned long)pfn_to_page(pfn + nr_pages)) - 1;
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end = PAGE_ALIGN(end);
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/* overlap check (because we have to align page */
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list_for_each_entry(tmp, head, list) {
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if (tmp->type != KCORE_VMEMMAP)
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continue;
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if (start < tmp->addr + tmp->size)
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if (end > tmp->addr)
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end = tmp->addr;
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}
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if (start < end) {
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vmm = kmalloc(sizeof(*vmm), GFP_KERNEL);
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if (!vmm)
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return 0;
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vmm->addr = start;
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vmm->size = end - start;
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vmm->type = KCORE_VMEMMAP;
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list_add_tail(&vmm->list, head);
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}
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return 1;
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}
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#else
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static int
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get_sparsemem_vmemmap_info(struct kcore_list *ent, struct list_head *head)
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{
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return 1;
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}
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#endif
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static int
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kclist_add_private(unsigned long pfn, unsigned long nr_pages, void *arg)
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{
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struct list_head *head = (struct list_head *)arg;
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struct kcore_list *ent;
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ent = kmalloc(sizeof(*ent), GFP_KERNEL);
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if (!ent)
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return -ENOMEM;
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ent->addr = (unsigned long)__va((pfn << PAGE_SHIFT));
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ent->size = nr_pages << PAGE_SHIFT;
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/* Sanity check: Can happen in 32bit arch...maybe */
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if (ent->addr < (unsigned long) __va(0))
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goto free_out;
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/* cut not-mapped area. ....from ppc-32 code. */
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if (ULONG_MAX - ent->addr < ent->size)
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ent->size = ULONG_MAX - ent->addr;
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/* cut when vmalloc() area is higher than direct-map area */
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if (VMALLOC_START > (unsigned long)__va(0)) {
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if (ent->addr > VMALLOC_START)
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goto free_out;
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if (VMALLOC_START - ent->addr < ent->size)
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ent->size = VMALLOC_START - ent->addr;
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}
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ent->type = KCORE_RAM;
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list_add_tail(&ent->list, head);
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if (!get_sparsemem_vmemmap_info(ent, head)) {
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list_del(&ent->list);
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goto free_out;
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}
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return 0;
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free_out:
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kfree(ent);
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return 1;
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}
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static int kcore_update_ram(void)
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{
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int nid, ret;
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unsigned long end_pfn;
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LIST_HEAD(head);
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/* Not inialized....update now */
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/* find out "max pfn" */
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end_pfn = 0;
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for_each_node_state(nid, N_MEMORY) {
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unsigned long node_end;
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node_end = node_end_pfn(nid);
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if (end_pfn < node_end)
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end_pfn = node_end;
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}
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/* scan 0 to max_pfn */
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ret = walk_system_ram_range(0, end_pfn, &head, kclist_add_private);
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if (ret) {
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free_kclist_ents(&head);
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return -ENOMEM;
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}
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__kcore_update_ram(&head);
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return ret;
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}
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#endif /* CONFIG_HIGHMEM */
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/*****************************************************************************/
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/*
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* determine size of ELF note
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*/
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static int notesize(struct memelfnote *en)
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{
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int sz;
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sz = sizeof(struct elf_note);
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sz += roundup((strlen(en->name) + 1), 4);
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sz += roundup(en->datasz, 4);
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return sz;
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} /* end notesize() */
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/*****************************************************************************/
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/*
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* store a note in the header buffer
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*/
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static char *storenote(struct memelfnote *men, char *bufp)
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{
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struct elf_note en;
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#define DUMP_WRITE(addr,nr) do { memcpy(bufp,addr,nr); bufp += nr; } while(0)
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en.n_namesz = strlen(men->name) + 1;
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en.n_descsz = men->datasz;
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en.n_type = men->type;
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DUMP_WRITE(&en, sizeof(en));
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DUMP_WRITE(men->name, en.n_namesz);
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/* XXX - cast from long long to long to avoid need for libgcc.a */
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bufp = (char*) roundup((unsigned long)bufp,4);
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DUMP_WRITE(men->data, men->datasz);
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bufp = (char*) roundup((unsigned long)bufp,4);
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#undef DUMP_WRITE
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return bufp;
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} /* end storenote() */
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/*
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* store an ELF coredump header in the supplied buffer
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* nphdr is the number of elf_phdr to insert
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*/
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static void elf_kcore_store_hdr(char *bufp, int nphdr, int dataoff)
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{
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struct elf_prstatus prstatus; /* NT_PRSTATUS */
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struct elf_prpsinfo prpsinfo; /* NT_PRPSINFO */
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struct elf_phdr *nhdr, *phdr;
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struct elfhdr *elf;
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struct memelfnote notes[3];
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off_t offset = 0;
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struct kcore_list *m;
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/* setup ELF header */
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elf = (struct elfhdr *) bufp;
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bufp += sizeof(struct elfhdr);
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offset += sizeof(struct elfhdr);
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memcpy(elf->e_ident, ELFMAG, SELFMAG);
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elf->e_ident[EI_CLASS] = ELF_CLASS;
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elf->e_ident[EI_DATA] = ELF_DATA;
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elf->e_ident[EI_VERSION]= EV_CURRENT;
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elf->e_ident[EI_OSABI] = ELF_OSABI;
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memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);
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elf->e_type = ET_CORE;
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elf->e_machine = ELF_ARCH;
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elf->e_version = EV_CURRENT;
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elf->e_entry = 0;
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elf->e_phoff = sizeof(struct elfhdr);
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elf->e_shoff = 0;
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elf->e_flags = ELF_CORE_EFLAGS;
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elf->e_ehsize = sizeof(struct elfhdr);
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elf->e_phentsize= sizeof(struct elf_phdr);
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elf->e_phnum = nphdr;
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elf->e_shentsize= 0;
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elf->e_shnum = 0;
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elf->e_shstrndx = 0;
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/* setup ELF PT_NOTE program header */
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nhdr = (struct elf_phdr *) bufp;
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bufp += sizeof(struct elf_phdr);
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offset += sizeof(struct elf_phdr);
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nhdr->p_type = PT_NOTE;
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nhdr->p_offset = 0;
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nhdr->p_vaddr = 0;
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nhdr->p_paddr = 0;
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nhdr->p_filesz = 0;
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nhdr->p_memsz = 0;
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nhdr->p_flags = 0;
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nhdr->p_align = 0;
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/* setup ELF PT_LOAD program header for every area */
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list_for_each_entry(m, &kclist_head, list) {
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phdr = (struct elf_phdr *) bufp;
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bufp += sizeof(struct elf_phdr);
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offset += sizeof(struct elf_phdr);
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phdr->p_type = PT_LOAD;
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phdr->p_flags = PF_R|PF_W|PF_X;
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phdr->p_offset = kc_vaddr_to_offset(m->addr) + dataoff;
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phdr->p_vaddr = (size_t)m->addr;
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if (m->type == KCORE_RAM || m->type == KCORE_TEXT)
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phdr->p_paddr = __pa(m->addr);
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else
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phdr->p_paddr = (elf_addr_t)-1;
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phdr->p_filesz = phdr->p_memsz = m->size;
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phdr->p_align = PAGE_SIZE;
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}
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/*
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* Set up the notes in similar form to SVR4 core dumps made
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* with info from their /proc.
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*/
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nhdr->p_offset = offset;
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/* set up the process status */
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notes[0].name = CORE_STR;
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notes[0].type = NT_PRSTATUS;
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notes[0].datasz = sizeof(struct elf_prstatus);
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notes[0].data = &prstatus;
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memset(&prstatus, 0, sizeof(struct elf_prstatus));
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nhdr->p_filesz = notesize(¬es[0]);
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bufp = storenote(¬es[0], bufp);
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/* set up the process info */
|
|
notes[1].name = CORE_STR;
|
|
notes[1].type = NT_PRPSINFO;
|
|
notes[1].datasz = sizeof(struct elf_prpsinfo);
|
|
notes[1].data = &prpsinfo;
|
|
|
|
memset(&prpsinfo, 0, sizeof(struct elf_prpsinfo));
|
|
prpsinfo.pr_state = 0;
|
|
prpsinfo.pr_sname = 'R';
|
|
prpsinfo.pr_zomb = 0;
|
|
|
|
strcpy(prpsinfo.pr_fname, "vmlinux");
|
|
strlcpy(prpsinfo.pr_psargs, saved_command_line, sizeof(prpsinfo.pr_psargs));
|
|
|
|
nhdr->p_filesz += notesize(¬es[1]);
|
|
bufp = storenote(¬es[1], bufp);
|
|
|
|
/* set up the task structure */
|
|
notes[2].name = CORE_STR;
|
|
notes[2].type = NT_TASKSTRUCT;
|
|
notes[2].datasz = arch_task_struct_size;
|
|
notes[2].data = current;
|
|
|
|
nhdr->p_filesz += notesize(¬es[2]);
|
|
bufp = storenote(¬es[2], bufp);
|
|
|
|
} /* end elf_kcore_store_hdr() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* read from the ELF header and then kernel memory
|
|
*/
|
|
static ssize_t
|
|
read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos)
|
|
{
|
|
char *buf = file->private_data;
|
|
ssize_t acc = 0;
|
|
size_t size, tsz;
|
|
size_t elf_buflen;
|
|
int nphdr;
|
|
unsigned long start;
|
|
|
|
read_lock(&kclist_lock);
|
|
size = get_kcore_size(&nphdr, &elf_buflen);
|
|
|
|
if (buflen == 0 || *fpos >= size) {
|
|
read_unlock(&kclist_lock);
|
|
return 0;
|
|
}
|
|
|
|
/* trim buflen to not go beyond EOF */
|
|
if (buflen > size - *fpos)
|
|
buflen = size - *fpos;
|
|
|
|
/* construct an ELF core header if we'll need some of it */
|
|
if (*fpos < elf_buflen) {
|
|
char * elf_buf;
|
|
|
|
tsz = elf_buflen - *fpos;
|
|
if (buflen < tsz)
|
|
tsz = buflen;
|
|
elf_buf = kzalloc(elf_buflen, GFP_ATOMIC);
|
|
if (!elf_buf) {
|
|
read_unlock(&kclist_lock);
|
|
return -ENOMEM;
|
|
}
|
|
elf_kcore_store_hdr(elf_buf, nphdr, elf_buflen);
|
|
read_unlock(&kclist_lock);
|
|
if (copy_to_user(buffer, elf_buf + *fpos, tsz)) {
|
|
kfree(elf_buf);
|
|
return -EFAULT;
|
|
}
|
|
kfree(elf_buf);
|
|
buflen -= tsz;
|
|
*fpos += tsz;
|
|
buffer += tsz;
|
|
acc += tsz;
|
|
|
|
/* leave now if filled buffer already */
|
|
if (buflen == 0)
|
|
return acc;
|
|
} else
|
|
read_unlock(&kclist_lock);
|
|
|
|
/*
|
|
* Check to see if our file offset matches with any of
|
|
* the addresses in the elf_phdr on our list.
|
|
*/
|
|
start = kc_offset_to_vaddr(*fpos - elf_buflen);
|
|
if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
|
|
tsz = buflen;
|
|
|
|
while (buflen) {
|
|
struct kcore_list *m;
|
|
|
|
read_lock(&kclist_lock);
|
|
list_for_each_entry(m, &kclist_head, list) {
|
|
if (start >= m->addr && start < (m->addr+m->size))
|
|
break;
|
|
}
|
|
read_unlock(&kclist_lock);
|
|
|
|
if (&m->list == &kclist_head) {
|
|
if (clear_user(buffer, tsz))
|
|
return -EFAULT;
|
|
} else if (m->type == KCORE_VMALLOC) {
|
|
vread(buf, (char *)start, tsz);
|
|
/* we have to zero-fill user buffer even if no read */
|
|
if (copy_to_user(buffer, buf, tsz))
|
|
return -EFAULT;
|
|
} else {
|
|
if (kern_addr_valid(start)) {
|
|
unsigned long n;
|
|
|
|
/*
|
|
* Using bounce buffer to bypass the
|
|
* hardened user copy kernel text checks.
|
|
*/
|
|
memcpy(buf, (char *) start, tsz);
|
|
n = copy_to_user(buffer, buf, tsz);
|
|
/*
|
|
* We cannot distinguish between fault on source
|
|
* and fault on destination. When this happens
|
|
* we clear too and hope it will trigger the
|
|
* EFAULT again.
|
|
*/
|
|
if (n) {
|
|
if (clear_user(buffer + tsz - n,
|
|
n))
|
|
return -EFAULT;
|
|
}
|
|
} else {
|
|
if (clear_user(buffer, tsz))
|
|
return -EFAULT;
|
|
}
|
|
}
|
|
buflen -= tsz;
|
|
*fpos += tsz;
|
|
buffer += tsz;
|
|
acc += tsz;
|
|
start += tsz;
|
|
tsz = (buflen > PAGE_SIZE ? PAGE_SIZE : buflen);
|
|
}
|
|
|
|
return acc;
|
|
}
|
|
|
|
|
|
static int open_kcore(struct inode *inode, struct file *filp)
|
|
{
|
|
if (!capable(CAP_SYS_RAWIO))
|
|
return -EPERM;
|
|
|
|
filp->private_data = kmalloc(PAGE_SIZE, GFP_KERNEL);
|
|
if (!filp->private_data)
|
|
return -ENOMEM;
|
|
|
|
if (kcore_need_update)
|
|
kcore_update_ram();
|
|
if (i_size_read(inode) != proc_root_kcore->size) {
|
|
inode_lock(inode);
|
|
i_size_write(inode, proc_root_kcore->size);
|
|
inode_unlock(inode);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int release_kcore(struct inode *inode, struct file *file)
|
|
{
|
|
kfree(file->private_data);
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations proc_kcore_operations = {
|
|
.read = read_kcore,
|
|
.open = open_kcore,
|
|
.release = release_kcore,
|
|
.llseek = default_llseek,
|
|
};
|
|
|
|
/* just remember that we have to update kcore */
|
|
static int __meminit kcore_callback(struct notifier_block *self,
|
|
unsigned long action, void *arg)
|
|
{
|
|
switch (action) {
|
|
case MEM_ONLINE:
|
|
case MEM_OFFLINE:
|
|
write_lock(&kclist_lock);
|
|
kcore_need_update = 1;
|
|
write_unlock(&kclist_lock);
|
|
}
|
|
return NOTIFY_OK;
|
|
}
|
|
|
|
static struct notifier_block kcore_callback_nb __meminitdata = {
|
|
.notifier_call = kcore_callback,
|
|
.priority = 0,
|
|
};
|
|
|
|
static struct kcore_list kcore_vmalloc;
|
|
|
|
#ifdef CONFIG_ARCH_PROC_KCORE_TEXT
|
|
static struct kcore_list kcore_text;
|
|
/*
|
|
* If defined, special segment is used for mapping kernel text instead of
|
|
* direct-map area. We need to create special TEXT section.
|
|
*/
|
|
static void __init proc_kcore_text_init(void)
|
|
{
|
|
kclist_add(&kcore_text, _text, _end - _text, KCORE_TEXT);
|
|
}
|
|
#else
|
|
static void __init proc_kcore_text_init(void)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
#if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
|
|
/*
|
|
* MODULES_VADDR has no intersection with VMALLOC_ADDR.
|
|
*/
|
|
struct kcore_list kcore_modules;
|
|
static void __init add_modules_range(void)
|
|
{
|
|
if (MODULES_VADDR != VMALLOC_START && MODULES_END != VMALLOC_END) {
|
|
kclist_add(&kcore_modules, (void *)MODULES_VADDR,
|
|
MODULES_END - MODULES_VADDR, KCORE_VMALLOC);
|
|
}
|
|
}
|
|
#else
|
|
static void __init add_modules_range(void)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
static int __init proc_kcore_init(void)
|
|
{
|
|
proc_root_kcore = proc_create("kcore", S_IRUSR, NULL,
|
|
&proc_kcore_operations);
|
|
if (!proc_root_kcore) {
|
|
pr_err("couldn't create /proc/kcore\n");
|
|
return 0; /* Always returns 0. */
|
|
}
|
|
/* Store text area if it's special */
|
|
proc_kcore_text_init();
|
|
/* Store vmalloc area */
|
|
kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
|
|
VMALLOC_END - VMALLOC_START, KCORE_VMALLOC);
|
|
add_modules_range();
|
|
/* Store direct-map area from physical memory map */
|
|
kcore_update_ram();
|
|
register_hotmemory_notifier(&kcore_callback_nb);
|
|
|
|
return 0;
|
|
}
|
|
fs_initcall(proc_kcore_init);
|