Currently for s390 we create the ELF core header in the 2nd kernel with a small trick. We relocate the addresses in the ELF header in a way that for the /proc/vmcore code it seems to be in the 1st kernel (old) memory and the read_from_oldmem() returns the correct data. This allows the /proc/vmcore code to use the ELF header in the 2nd kernel.
This patch now exchanges the old mechanism with the new and much cleaner ELFCORE_ADDR_NEWMEM feature that now offcially allows to create the ELF core header in the 2nd kernel. Signed-off-by: Michael Holzheu <[email protected]> --- arch/s390/kernel/crash_dump.c | 26 +++++++------------------- arch/s390/kernel/setup.c | 2 +- 2 files changed, 8 insertions(+), 20 deletions(-) diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index fb8d878..f1feaaa 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -325,14 +325,6 @@ static int get_mem_chunk_cnt(void) } /* - * Relocate pointer in order to allow vmcore code access the data - */ -static inline unsigned long relocate(unsigned long addr) -{ - return OLDMEM_BASE + addr; -} - -/* * Initialize ELF loads (new kernel) */ static int loads_init(Elf64_Phdr *phdr, u64 loads_offset) @@ -383,7 +375,7 @@ static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset) ptr = nt_vmcoreinfo(ptr); memset(phdr, 0, sizeof(*phdr)); phdr->p_type = PT_NOTE; - phdr->p_offset = relocate(notes_offset); + phdr->p_offset = notes_offset; phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start); phdr->p_memsz = phdr->p_filesz; return ptr; @@ -392,7 +384,7 @@ static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset) /* * Create ELF core header (new kernel) */ -static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz) +int arch_vmcore_get_elf_hdr(char **elfcorebuf, size_t *elfcorebuf_sz) { Elf64_Phdr *phdr_notes, *phdr_loads; int mem_chunk_cnt; @@ -414,13 +406,14 @@ static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz) ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr) * mem_chunk_cnt); /* Init notes */ hdr_off = PTR_DIFF(ptr, hdr); - ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off); + ptr = notes_init(phdr_notes, ptr, hdr_off); /* Init loads */ hdr_off = PTR_DIFF(ptr, hdr); - loads_init(phdr_loads, ((unsigned long) hdr) + hdr_off); + loads_init(phdr_loads, hdr_off); *elfcorebuf_sz = hdr_off; - *elfcorebuf = (void *) relocate((unsigned long) hdr); + *elfcorebuf = hdr; BUG_ON(*elfcorebuf_sz > alloc_size); + return 0; } /* @@ -429,14 +422,9 @@ static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz) */ static int setup_kdump_elfcorehdr(void) { - size_t elfcorebuf_sz; - char *elfcorebuf; - if (!OLDMEM_BASE || is_kdump_kernel()) return -EINVAL; - s390_elf_corehdr_create(&elfcorebuf, &elfcorebuf_sz); - elfcorehdr_addr = (unsigned long long) elfcorebuf; - elfcorehdr_size = elfcorebuf_sz; + elfcorehdr_addr = ELFCORE_ADDR_NEWMEM; return 0; } diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index 0f419c5..86f2ca1 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -889,7 +889,7 @@ static void __init setup_memory(void) reserve_bootmem(crashk_res.start, crashk_res.end - crashk_res.start + 1, BOOTMEM_DEFAULT); - if (is_kdump_kernel()) + if (is_kdump_kernel() && (elfcorehdr_addr != ELFCORE_ADDR_NEWMEM)) reserve_bootmem(elfcorehdr_addr - OLDMEM_BASE, PAGE_ALIGN(elfcorehdr_size), BOOTMEM_DEFAULT); #endif -- 1.8.1.6 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
