On 04/11/2022 17:03, Li, Zhijian/李 智坚 wrote: > Hi folks, > > I'm trying to add pmem's metadata(located at pmem device) to > /proc/vmcore. To accomplish this, I think > > something i need to know is where the contents of /proc/vmcore come > from, and then append > > something into it. > > I have read > https://opensource.com/article/17/6/kdump-usage-and-internals, and knew > /proc/vmcore is a elf file. > > It mentioned that "Creates /proc/vmcore as per elfcorehdr information > received", but i don't get how it > > elfcorehdr(maybe elfcorehdr_addr) be assigned in 2nd kernel. I got it, elfcorehdr comes from 1st kernel's kexec-tools which passes elfcorehdr=xxx to 2nd kernel Thanks > > I tried to grep it in the kernel source, but still no answer. So i deep > hope you guys can give me some hints or answer. > > and thank you in advance :) > > [root@iaas-rpma linux]# git grep elfcorehdr_addr | grep -v -w -e ia64 -e > loongarch -e mips -e powerpc -e riscv > > arch/s390/kernel/setup.c: elfcorehdr_addr = ELFCORE_ADDR_MAX; > > drivers/of/fdt.c: if (memblock_is_region_reserved(elfcorehdr_addr, > elfcorehdr_size)) { > > drivers/of/fdt.c: memblock_reserve(elfcorehdr_addr, elfcorehdr_size); > > drivers/of/fdt.c: elfcorehdr_size >> 10, elfcorehdr_addr); > > drivers/of/fdt.c: elfcorehdr_addr = > dt_mem_next_cell(dt_root_addr_cells, &prop); > > drivers/of/fdt.c: elfcorehdr_addr, elfcorehdr_size); > > fs/proc/vmcore.c: addr = elfcorehdr_addr; > > fs/proc/vmcore.c: addr = elfcorehdr_addr; > > fs/proc/vmcore.c: addr = elfcorehdr_addr; > > fs/proc/vmcore.c: addr = elfcorehdr_addr; > > fs/proc/vmcore.c: addr = elfcorehdr_addr; > > fs/proc/vmcore.c: rc = elfcorehdr_alloc(&elfcorehdr_addr, > &elfcorehdr_size); > > fs/proc/vmcore.c: elfcorehdr_free(elfcorehdr_addr); > > fs/proc/vmcore.c: elfcorehdr_addr = ELFCORE_ADDR_ERR; > > include/linux/crash_dump.h:extern unsigned long long elfcorehdr_addr; > > include/linux/crash_dump.h: return elfcorehdr_addr != ELFCORE_ADDR_MAX; > > include/linux/crash_dump.h: return is_kdump_kernel() && > elfcorehdr_addr != ELFCORE_ADDR_ERR ? 1 : 0; > > include/linux/crash_dump.h: elfcorehdr_addr = ELFCORE_ADDR_ERR; > > kernel/crash_dump.c: * Note: elfcorehdr_addr is not just limited to > vmcore. It is also used by > > kernel/crash_dump.c:unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX; > > kernel/crash_dump.c:EXPORT_SYMBOL_GPL(elfcorehdr_addr); > > kernel/crash_dump.c: elfcorehdr_addr = memparse(arg, &end); > > kernel/crash_dump.c: elfcorehdr_size = elfcorehdr_addr; > > kernel/crash_dump.c: elfcorehdr_addr = memparse(end + 1, &end); > > Thanks > > Zhijian _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
