From: Yinghai Lu Date: Fri, 21 Mar 2008 06:58:33 +0000 (-0700) Subject: x86: early memtest to find bad ram X-Git-Tag: v2.6.26-rc1~1154^2~297 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=272b9cad6e7a2f61b13cfcd7dde0010e02e9376e;p=linux-2.6 x86: early memtest to find bad ram do simple memtest after init_memory_mapping use find_e820_area_size to find all ram range that is not reserved. and do some simple bits test to find some bad ram. if find some bad ram, use reserve_early to exclude that range. Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/kernel/e820_64.c b/arch/x86/kernel/e820_64.c index 4a0953857c..4509757844 100644 --- a/arch/x86/kernel/e820_64.c +++ b/arch/x86/kernel/e820_64.c @@ -114,6 +114,40 @@ again: return changed; } +/* Check for already reserved areas */ +static inline int +bad_addr_size(unsigned long *addrp, unsigned long *sizep, unsigned long align) +{ + int i; + unsigned long addr = *addrp, last; + unsigned long size = *sizep; + int changed = 0; +again: + last = addr + size; + for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) { + struct early_res *r = &early_res[i]; + if (last > r->start && addr < r->start) { + size = r->start - addr; + changed = 1; + goto again; + } + if (last > r->end && addr < r->end) { + addr = round_up(r->end, align); + size = last - addr; + changed = 1; + goto again; + } + if (last <= r->end && addr >= r->start) { + (*sizep)++; + return 0; + } + } + if (changed) { + *addrp = addr; + *sizep = size; + } + return changed; +} /* * This function checks if any part of the range is mapped * with type. @@ -190,7 +224,7 @@ unsigned long __init find_e820_area(unsigned long start, unsigned long end, ei_last = ei->addr + ei->size; if (addr < start) addr = round_up(start, align); - if (addr > ei_last) + if (addr >= ei_last) continue; while (bad_addr(&addr, size, align) && addr+size <= ei_last) ; @@ -204,6 +238,40 @@ unsigned long __init find_e820_area(unsigned long start, unsigned long end, return -1UL; } +/* + * Find next free range after *start + */ +unsigned long __init find_e820_area_size(unsigned long start, unsigned long *sizep, unsigned long align) +{ + int i; + + for (i = 0; i < e820.nr_map; i++) { + struct e820entry *ei = &e820.map[i]; + unsigned long addr, last; + unsigned long ei_last; + + if (ei->type != E820_RAM) + continue; + addr = round_up(ei->addr, align); + ei_last = ei->addr + ei->size; +// printk(KERN_DEBUG "find_e820_area_size : e820 %d [%llx, %lx]\n", i, ei->addr, ei_last); + if (addr < start) + addr = round_up(start, align); +// printk(KERN_DEBUG "find_e820_area_size : 0 [%lx, %lx]\n", addr, ei_last); + if (addr >= ei_last) + continue; + *sizep = ei_last - addr; + while (bad_addr_size(&addr, sizep, align) && addr+ *sizep <= ei_last) + ; + last = addr + *sizep; +// printk(KERN_DEBUG "find_e820_area_size : 1 [%lx, %lx]\n", addr, last); + if (last > ei_last) + continue; + return addr; + } + return -1UL; + +} /* * Find the highest page frame number we have available */ diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 255e51feb1..52f54ee455 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -427,6 +427,106 @@ static void __init init_gbpages(void) direct_gbpages = 0; } +static void __init memtest(unsigned long start_phys, unsigned long size, unsigned pattern) +{ + unsigned long i; + unsigned long *start; + unsigned long start_bad; + unsigned long last_bad; + unsigned long val; + unsigned long start_phys_aligned; + unsigned long count; + unsigned long incr; + + switch (pattern) { + case 0: + val = 0UL; + break; + case 1: + val = -1UL; + break; + case 2: + val = 0x5555555555555555UL; + break; + case 3: + val = 0xaaaaaaaaaaaaaaaaUL; + break; + default: + return; + } + + incr = sizeof(unsigned long); + start_phys_aligned = ALIGN(start_phys, incr); + count = (size - (start_phys_aligned - start_phys))/incr; + start = __va(start_phys_aligned); + start_bad = 0; + last_bad = 0; + + for (i = 0; i < count; i++) + start[i] = val; + for (i = 0; i < count; i++, start++, start_phys_aligned += incr) { + if (*start != val) { + if (start_phys_aligned == last_bad + incr) { + last_bad += incr; + } else { + if (start_bad) { + printk(KERN_INFO " %016lxx bad mem addr %016lx - %016lx reserved\n", + val, start_bad, last_bad + incr); + reserve_early(start_bad, last_bad - start_bad, "BAD RAM"); + } + start_bad = last_bad = start_phys_aligned; + } + } + } + if (start_bad) { + printk(KERN_INFO " %016lx bad mem addr %016lx - %016lx reserved\n", + val, start_bad, last_bad + incr); + reserve_early(start_bad, last_bad - start_bad, "BAD RAM"); + } + +} + +static int __initdata memtest_pattern; +static int __init parse_memtest(char *arg) +{ + if (arg) + memtest_pattern = simple_strtoul(arg, NULL, 0) + 1; + return 0; +} + +early_param("memtest", parse_memtest); + +static void __init early_memtest(unsigned long start, unsigned long end) +{ + unsigned long t_start, t_size; + unsigned pattern; + + if (memtest_pattern) + printk(KERN_INFO "early_memtest: pattern num %d", memtest_pattern); + for (pattern = 0; pattern < memtest_pattern; pattern++) { + t_start = start; + t_size = 0; + while (t_start < end) { + t_start = find_e820_area_size(t_start, &t_size, 1); + + /* done ? */ + if (t_start >= end) + break; + if (t_start + t_size > end) + t_size = end - t_start; + + printk(KERN_CONT "\n %016lx - %016lx pattern %d", + t_start, t_start + t_size, pattern); + + memtest(t_start, t_size, pattern); + + t_start += t_size; + } + } + if (memtest_pattern) + printk(KERN_CONT "\n"); +} + /* * Setup the direct mapping of the physical memory at PAGE_OFFSET. * This runs before bootmem is initialized and gets pages directly from @@ -435,8 +535,9 @@ static void __init init_gbpages(void) void __init_refok init_memory_mapping(unsigned long start, unsigned long end) { unsigned long next; + unsigned long start_phys = start, end_phys = end; - pr_debug("init_memory_mapping\n"); + printk(KERN_INFO "init_memory_mapping\n"); /* * Find space for the kernel direct mapping tables. @@ -479,6 +580,9 @@ void __init_refok init_memory_mapping(unsigned long start, unsigned long end) if (!after_bootmem) reserve_early(table_start << PAGE_SHIFT, table_end << PAGE_SHIFT, "PGTABLE"); + + if (!after_bootmem) + early_memtest(start_phys, end_phys); } #ifndef CONFIG_NUMA diff --git a/include/asm-x86/e820_64.h b/include/asm-x86/e820_64.h index ef653a403e..d38820b31c 100644 --- a/include/asm-x86/e820_64.h +++ b/include/asm-x86/e820_64.h @@ -16,6 +16,9 @@ #ifndef __ASSEMBLY__ extern unsigned long find_e820_area(unsigned long start, unsigned long end, unsigned long size, unsigned long align); +extern unsigned long find_e820_area_size(unsigned long start, + unsigned long *sizep, + unsigned long align); extern void add_memory_region(unsigned long start, unsigned long size, int type); extern void update_memory_range(u64 start, u64 size, unsigned old_type,