Commit-ID: 4dae560f97fa438f373b53e14b30149c9e44a600 Gitweb: http://git.kernel.org/tip/4dae560f97fa438f373b53e14b30149c9e44a600 Author: Ananth N Mavinakayanahalli <ananth@xxxxxxxxxx> AuthorDate: Fri, 30 Oct 2009 19:23:10 +0530 Committer: Ingo Molnar <mingo@xxxxxxx> CommitDate: Mon, 2 Nov 2009 17:00:18 +0100 kprobes: Sanitize struct kretprobe_instance allocations For as long as kretprobes have existed, we've allocated NR_CPUS instances of kretprobe_instance structures. With the default value of CONFIG_NR_CPUS increasing on certain architectures, we are potentially wasting kernel memory. See http://sourceware.org/bugzilla/show_bug.cgi?id=10839#c3 for more details. Use a saner num_possible_cpus() instead of NR_CPUS for allocation. Signed-off-by: Ananth N Mavinakayanahalli <ananth@xxxxxxxxxx> Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx> Cc: Jim Keniston <jkenisto@xxxxxxxxxx> Cc: fweisbec@xxxxxxxxx LKML-Reference: <20091030135310.GA22230@xxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> --- kernel/kprobes.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 5240d75..1494e85 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1014,9 +1014,9 @@ int __kprobes register_kretprobe(struct kretprobe *rp) /* Pre-allocate memory for max kretprobe instances */ if (rp->maxactive <= 0) { #ifdef CONFIG_PREEMPT - rp->maxactive = max(10, 2 * NR_CPUS); + rp->maxactive = max(10, 2 * num_possible_cpus()); #else - rp->maxactive = NR_CPUS; + rp->maxactive = num_possible_cpus(); #endif } spin_lock_init(&rp->lock); -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html