From 1f383de442a419719650d3ff4c0aa7542f301a92 Mon Sep 17 00:00:00 2001 From: Masanori ITOH Date: Tue, 26 Oct 2010 14:21:20 -0700 Subject: percpu: fix list_head init bug in __percpu_counter_init() commit 8474b591faf3bb0a1e08a60d21d6baac498f15e4 upstream. WARNING: at lib/list_debug.c:26 __list_add+0x3f/0x81() Hardware name: Express5800/B120a [N8400-085] list_add corruption. next->prev should be prev (ffffffff81a7ea00), but was dead000000200200. (next=ffff88080b872d58). Modules linked in: aoe ipt_MASQUERADE iptable_nat nf_nat autofs4 sunrpc bridge 8021q garp stp llc ipv6 cpufreq_ondemand acpi_cpufreq freq_table dm_round_robin dm_multipath kvm_intel kvm uinput lpfc scsi_transport_fc igb ioatdma scsi_tgt i2c_i801 i2c_core dca iTCO_wdt iTCO_vendor_support pcspkr shpchp megaraid_sas [last unloaded: aoe] Pid: 54, comm: events/3 Tainted: G W 2.6.34-vanilla1 #1 Call Trace: [] warn_slowpath_common+0x7c/0x94 [] warn_slowpath_fmt+0x41/0x43 [] __list_add+0x3f/0x81 [] __percpu_counter_init+0x59/0x6b [] bdi_init+0x118/0x17e [] blk_alloc_queue_node+0x79/0x143 [] blk_alloc_queue+0x11/0x13 [] aoeblk_gdalloc+0x8e/0x1c9 [aoe] [] aoecmd_sleepwork+0x25/0xa8 [aoe] [] worker_thread+0x1a9/0x237 [] ? aoecmd_sleepwork+0x0/0xa8 [aoe] [] ? autoremove_wake_function+0x0/0x39 [] ? worker_thread+0x0/0x237 [] kthread+0x7f/0x87 [] kernel_thread_helper+0x4/0x10 [] ? kthread+0x0/0x87 [] ? kernel_thread_helper+0x0/0x10 It's because there is no initialization code for a list_head contained in the struct backing_dev_info under CONFIG_HOTPLUG_CPU, and the bug comes up when block device drivers calling blk_alloc_queue() are used. In case of me, I got them by using aoe. Signed-off-by: Masanori Itoh Cc: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- lib/percpu_counter.c | 1 + 1 file changed, 1 insertion(+) diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c index aeaa6d73444..9d942128c15 100644 --- a/lib/percpu_counter.c +++ b/lib/percpu_counter.c @@ -76,6 +76,7 @@ int __percpu_counter_init(struct percpu_counter *fbc, s64 amount, if (!fbc->counters) return -ENOMEM; #ifdef CONFIG_HOTPLUG_CPU + INIT_LIST_HEAD(&fbc->list); mutex_lock(&percpu_counters_lock); list_add(&fbc->list, &percpu_counters); mutex_unlock(&percpu_counters_lock); -- cgit v1.2.3-18-g5258