From 4893fc8856a81d2037c1c976cb320be6f00e84a0 Mon Sep 17 00:00:00 2001 From: Corey Minyard Date: Tue, 12 Feb 2013 19:41:48 +0000 Subject: [PATCH] mips: reserve elfcorehdr /proc/vmcore wasn't showing up in kdump kernels. It turns that that for Octeon, the memory used by elfcorehdr wasn't being set aside properly and it was getting clobbered before /proc/vmcore could get it. So reserve the memory if it shows up in a memory area managed by the kernel. Signed-off-by: Corey Minyard Acked-by: David Daney Cc: Ralf Baechle Patchwork: http://patchwork.linux-mips.org/patch/4936/ --- arch/mips/kernel/setup.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index 53462500c3cd..795f4379c0b6 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -480,6 +480,37 @@ static int __init early_parse_mem(char *p) } early_param("mem", early_parse_mem); +#ifdef CONFIG_PROC_VMCORE +unsigned long setup_elfcorehdr, setup_elfcorehdr_size; +static int __init early_parse_elfcorehdr(char *p) +{ + int i; + + setup_elfcorehdr = memparse(p, &p); + + for (i = 0; i < boot_mem_map.nr_map; i++) { + unsigned long start = boot_mem_map.map[i].addr; + unsigned long end = (boot_mem_map.map[i].addr + + boot_mem_map.map[i].size); + if (setup_elfcorehdr >= start && setup_elfcorehdr < end) { + /* + * Reserve from the elf core header to the end of + * the memory segment, that should all be kdump + * reserved memory. + */ + setup_elfcorehdr_size = end - setup_elfcorehdr; + break; + } + } + /* + * If we don't find it in the memory map, then we shouldn't + * have to worry about it, as the new kernel won't use it. + */ + return 0; +} +early_param("elfcorehdr", early_parse_elfcorehdr); +#endif + static void __init arch_mem_addpart(phys_t mem, phys_t end, int type) { phys_t size; @@ -547,6 +578,14 @@ static void __init arch_mem_init(char **cmdline_p) } bootmem_init(); +#ifdef CONFIG_PROC_VMCORE + if (setup_elfcorehdr && setup_elfcorehdr_size) { + printk(KERN_INFO "kdump reserved memory at %lx-%lx\n", + setup_elfcorehdr, setup_elfcorehdr_size); + reserve_bootmem(setup_elfcorehdr, setup_elfcorehdr_size, + BOOTMEM_DEFAULT); + } +#endif #ifdef CONFIG_KEXEC if (crashk_res.start != crashk_res.end) reserve_bootmem(crashk_res.start, -- 2.39.5