crashkernel=x@y or or =range1:size1[,range2:size2,...]@offset option may fail to reserve the required memory region if KASLR puts kernel into the region. To avoid this uncertainty, asking KASLR to skip the required region.
Signed-off-by: Pingfan Liu <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Baoquan He <[email protected]> Cc: Will Deacon <[email protected]> Cc: Nicolas Pitre <[email protected]> Cc: Vivek Goyal <[email protected]> Cc: Chao Fan <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Cc: Ard Biesheuvel <[email protected]> CC: Hari Bathini <[email protected]> Cc: [email protected] --- arch/x86/boot/compressed/kaslr.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 2e53c05..765a593 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -107,6 +107,7 @@ enum mem_avoid_index { MEM_AVOID_BOOTPARAMS, MEM_AVOID_MEMMAP_BEGIN, MEM_AVOID_MEMMAP_END = MEM_AVOID_MEMMAP_BEGIN + MAX_MEMMAP_REGIONS - 1, + MEM_AVOID_CRASHKERNEL, MEM_AVOID_MAX, }; @@ -131,6 +132,11 @@ char *skip_spaces(const char *str) } #include "../../../../lib/ctype.c" #include "../../../../lib/cmdline.c" +#ifdef CONFIG_CRASH_CORE +#define printk +#define _BOOT_KASLR +#include "../../../../lib/parse_crashkernel.c" +#endif static int parse_memmap(char *p, unsigned long long *start, unsigned long long *size) @@ -292,6 +298,39 @@ static void handle_mem_options(void) return; } +static u64 mem_ram_size(void) +{ + struct boot_e820_entry *entry; + u64 total_sz = 0; + int i; + + for (i = 0; i < boot_params->e820_entries; i++) { + entry = &boot_params->e820_table[i]; + /* Skip non-RAM entries. */ + if (entry->type != E820_TYPE_RAM) + continue; + total_sz += entry->size; + } + return total_sz; +} + +/* + * For crashkernel=size@offset or =range1:size1[,range2:size2,...]@offset + * options, recording mem_avoid for them. + */ +static void handle_crashkernel_options(void) +{ + unsigned long long crash_size, crash_base = 0; + char *cmdline = (char *)get_cmd_line_ptr(); + u64 total_sz = mem_ram_size(); + + parse_crashkernel(cmdline, total_sz, &crash_size, &crash_base); + if (crash_base) { + mem_avoid[MEM_AVOID_CRASHKERNEL].start = crash_base; + mem_avoid[MEM_AVOID_CRASHKERNEL].size = crash_size; + } +} + /* * In theory, KASLR can put the kernel anywhere in the range of [16M, 64T). * The mem_avoid array is used to store the ranges that need to be avoided @@ -414,6 +453,7 @@ static void mem_avoid_init(unsigned long input, unsigned long input_size, /* Mark the memmap regions we need to avoid */ handle_mem_options(); + handle_crashkernel_options(); /* Enumerate the immovable memory regions */ num_immovable_mem = count_immovable_mem_regions(); -- 2.7.4
