...but only if you provide BOOTMEM_EXCLUSIVE, which should guarantee that you're actually checking the return value. In that case, just return an error code if the memory you tried to get is invalid. This lets callers safely probe around for a valid memory range. If you don't use BOOTMEM_EXCLUSIVE and the memory address is invalid, just crash as before, since the caller is probably not bothering to check the return value. Signed-off-by: Avery Pennarun <apenwarr@xxxxxxxxx> --- mm/bootmem.c | 7 +++++-- 1 files changed, 5 insertions(+), 2 deletions(-) diff --git a/mm/bootmem.c b/mm/bootmem.c index 7a9f505..d397dae 100644 --- a/mm/bootmem.c +++ b/mm/bootmem.c @@ -351,7 +351,10 @@ static int __init mark_bootmem(unsigned long start, unsigned long end, return 0; pos = bdata->node_low_pfn; } - BUG(); + /* people who don't use BOOTMEM_EXCLUSIVE don't check the return + * value, so BUG() if it goes wrong. */ + BUG_ON(!(reserve && (flags & BOOTMEM_EXCLUSIVE)); + return -ENOENT; } /** @@ -421,7 +424,7 @@ int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr, } /** - * reserve_bootmem - mark a page range as usable + * reserve_bootmem - mark a page range as reserved * @addr: starting address of the range * @size: size of the range in bytes * @flags: reservation flags (see linux/bootmem.h) -- 1.7.7.3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>