diff options
Diffstat (limited to 'fs/proc')
-rw-r--r-- | fs/proc/vmcore.c | 61 |
1 files changed, 51 insertions, 10 deletions
diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c index a1a16eb97c7b..02cb3ff108bc 100644 --- a/fs/proc/vmcore.c +++ b/fs/proc/vmcore.c @@ -123,6 +123,36 @@ static ssize_t read_from_oldmem(char *buf, size_t count, return read; } +/* + * Architectures may override this function to allocate ELF header in 2nd kernel + */ +int __weak elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size) +{ + return 0; +} + +/* + * Architectures may override this function to free header + */ +void __weak elfcorehdr_free(unsigned long long addr) +{} + +/* + * Architectures may override this function to read from ELF header + */ +ssize_t __weak elfcorehdr_read(char *buf, size_t count, u64 *ppos) +{ + return read_from_oldmem(buf, count, ppos, 0); +} + +/* + * Architectures may override this function to read from notes sections + */ +ssize_t __weak elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos) +{ + return read_from_oldmem(buf, count, ppos, 0); +} + /* Read from the ELF header and then the crash dump. On error, negative value is * returned otherwise number of bytes read are returned. */ @@ -357,7 +387,7 @@ static int __init update_note_header_size_elf64(const Elf64_Ehdr *ehdr_ptr) notes_section = kmalloc(max_sz, GFP_KERNEL); if (!notes_section) return -ENOMEM; - rc = read_from_oldmem(notes_section, max_sz, &offset, 0); + rc = elfcorehdr_read_notes(notes_section, max_sz, &offset); if (rc < 0) { kfree(notes_section); return rc; @@ -444,7 +474,8 @@ static int __init copy_notes_elf64(const Elf64_Ehdr *ehdr_ptr, char *notes_buf) if (phdr_ptr->p_type != PT_NOTE) continue; offset = phdr_ptr->p_offset; - rc = read_from_oldmem(notes_buf, phdr_ptr->p_memsz, &offset, 0); + rc = elfcorehdr_read_notes(notes_buf, phdr_ptr->p_memsz, + &offset); if (rc < 0) return rc; notes_buf += phdr_ptr->p_memsz; @@ -536,7 +567,7 @@ static int __init update_note_header_size_elf32(const Elf32_Ehdr *ehdr_ptr) notes_section = kmalloc(max_sz, GFP_KERNEL); if (!notes_section) return -ENOMEM; - rc = read_from_oldmem(notes_section, max_sz, &offset, 0); + rc = elfcorehdr_read_notes(notes_section, max_sz, &offset); if (rc < 0) { kfree(notes_section); return rc; @@ -623,7 +654,8 @@ static int __init copy_notes_elf32(const Elf32_Ehdr *ehdr_ptr, char *notes_buf) if (phdr_ptr->p_type != PT_NOTE) continue; offset = phdr_ptr->p_offset; - rc = read_from_oldmem(notes_buf, phdr_ptr->p_memsz, &offset, 0); + rc = elfcorehdr_read_notes(notes_buf, phdr_ptr->p_memsz, + &offset); if (rc < 0) return rc; notes_buf += phdr_ptr->p_memsz; @@ -810,7 +842,7 @@ static int __init parse_crash_elf64_headers(void) addr = elfcorehdr_addr; /* Read Elf header */ - rc = read_from_oldmem((char*)&ehdr, sizeof(Elf64_Ehdr), &addr, 0); + rc = elfcorehdr_read((char *)&ehdr, sizeof(Elf64_Ehdr), &addr); if (rc < 0) return rc; @@ -837,7 +869,7 @@ static int __init parse_crash_elf64_headers(void) if (!elfcorebuf) return -ENOMEM; addr = elfcorehdr_addr; - rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz_orig, &addr, 0); + rc = elfcorehdr_read(elfcorebuf, elfcorebuf_sz_orig, &addr); if (rc < 0) goto fail; @@ -866,7 +898,7 @@ static int __init parse_crash_elf32_headers(void) addr = elfcorehdr_addr; /* Read Elf header */ - rc = read_from_oldmem((char*)&ehdr, sizeof(Elf32_Ehdr), &addr, 0); + rc = elfcorehdr_read((char *)&ehdr, sizeof(Elf32_Ehdr), &addr); if (rc < 0) return rc; @@ -892,7 +924,7 @@ static int __init parse_crash_elf32_headers(void) if (!elfcorebuf) return -ENOMEM; addr = elfcorehdr_addr; - rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz_orig, &addr, 0); + rc = elfcorehdr_read(elfcorebuf, elfcorebuf_sz_orig, &addr); if (rc < 0) goto fail; @@ -919,7 +951,7 @@ static int __init parse_crash_elf_headers(void) int rc=0; addr = elfcorehdr_addr; - rc = read_from_oldmem(e_ident, EI_NIDENT, &addr, 0); + rc = elfcorehdr_read(e_ident, EI_NIDENT, &addr); if (rc < 0) return rc; if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) { @@ -952,7 +984,14 @@ static int __init vmcore_init(void) { int rc = 0; - /* If elfcorehdr= has been passed in cmdline, then capture the dump.*/ + /* Allow architectures to allocate ELF header in 2nd kernel */ + rc = elfcorehdr_alloc(&elfcorehdr_addr, &elfcorehdr_size); + if (rc) + return rc; + /* + * If elfcorehdr= has been passed in cmdline or created in 2nd kernel, + * then capture the dump. + */ if (!(is_vmcore_usable())) return rc; rc = parse_crash_elf_headers(); @@ -960,6 +999,8 @@ static int __init vmcore_init(void) pr_warn("Kdump: vmcore not initialized\n"); return rc; } + elfcorehdr_free(elfcorehdr_addr); + elfcorehdr_addr = ELFCORE_ADDR_ERR; proc_vmcore = proc_create("vmcore", S_IRUSR, NULL, &proc_vmcore_operations); if (proc_vmcore) |