Messages in this thread | | | From | Ed Cashin <> | Date | Thu, 3 Jan 2013 12:15:35 -0600 | Subject | Re: Oops on aoe module removal |
| |
On Jan 3, 2013, at 10:34 AM, Jens Axboe wrote:
> On 2013-01-03 16:28, Ed Cashin wrote: >> On Jan 3, 2013, at 9:12 AM, Jens Axboe wrote: >> >>> On 2013-01-03 15:09, Jens Axboe wrote: >>>> On 2013-01-03 15:02, Ed Cashin wrote: >>>>> On Jan 3, 2013, at 8:25 AM, Josh Boyer wrote: >>>>> >>>>>> Hello, >>>>>> >>>>>> We have a user that has reported an oops when removing the aoe module. >>>>>> This seems to have been happening since the 3.4 kernel, as you can see >>>>>> in this bug: https://bugzilla.redhat.com/show_bug.cgi?id=853064 >>>>>> >>>>>> The recreate steps and oops output from a 3.6.11 kernel is below. Any >>>>>> thoughts on what could be causing this? >>>>>> >>>>>> josh >>>>>> >>>>>> >>>>>> I run the following commands sequentially >>>>>> >>>>>> - modprobe aoe >>>>>> - dmesg: >>>>>> [699170.611997] aoe: AoE v47 initialised. >>>>>> [699170.653980] aoe: e4.1: setting 8192 byte data frames on eth1:000423d36ac3 >>>>>> [699170.654106] aoe: e6.0: setting 8192 byte data frames on eth1:000423d36ac3 >>>>>> [699170.654961] aoe: e6.2: setting 8192 byte data frames on eth1:000423d36ac3 >>>>>> [699170.654961] aoe: e6.3: setting 8192 byte data frames on eth1:000423d36ac3 >>>>>> [699170.654961] aoe: e8.1: setting 8192 byte data frames on eth1:000423d36ac3 >>>>>> [699170.654961] aoe: e8.2: setting 8192 byte data frames on eth1:000423d36ac3 >>>>>> [699170.654961] aoe: e8.10: setting 8192 byte data frames on eth1:000423d36ac3 >>>>>> [699170.654961] aoe: e8.11: setting 8192 byte data frames on eth1:000423d36ac3 >>>>>> [699170.654961] aoe: 000423d36ac3 e4.1 v0100 has 33554432 sectors >>>>>> [699170.654961] aoe: 000423d36ac3 e6.0 v0100 has 12582912 sectors >>>>>> [699170.654961] aoe: 000423d36ac3 e6.2 v0100 has 16777216 sectors >>>>>> [699170.702143] aoe: 000423d36ac3 e6.3 v0100 has 104857600 sectors >>>>>> [699170.706391] aoe: 000423d36ac3 e8.1 v0100 has 272629760 sectors >>>>>> [699170.710623] aoe: 000423d36ac3 e8.2 v0100 has 67108864 sectors >>>>>> [699170.714851] aoe: 000423d36ac3 e8.10 v0100 has 33554432 sectors >>>>>> [699170.719056] aoe: 000423d36ac3 e8.11 v0100 has 67108864 sectors >>>>>> [699170.824774] etherd/e4.1: p1 >>>>>> [699170.829069] etherd/e6.0: p1 p2 >>>>>> [699170.833274] etherd/e8.1: p1 p2 >>>>>> [699170.837329] etherd/e8.2: p1 >>>>>> [699170.841204] etherd/e8.10: p1 >>>>>> [699170.845030] etherd/e8.11: p1 >>>>>> [699170.848706] etherd/e6.3: unknown partition table >>>>>> [699170.852384] etherd/e6.2: unknown partition table >>>>>> >>>>>> - lsmod |grep aoe >>>>>> aoe 32214 0 >>>>>> >>>>>> - modprobe -vr aoe >>>>>> - dmesg: >>>>>> [699231.304689] ------------[ cut here ]------------ >>>>>> [699231.308319] WARNING: at lib/list_debug.c:62 __list_del_entry+0x82/0xd0() >>>>>> [699231.312031] Hardware name: S5000VSA >>>>>> [699231.315658] list_del corruption. next->prev should be ffff880009fa37e8, but was ffffffff81c79c00 >>>>>> [699231.319352] Modules linked in: aoe(-) ip6table_filter ip6_tables ebtable_nat ebtables lockd sunrpc bridge 8021q garp stp llc vfat fat binfmt_misc iTCO_wdt iTCO_vendor_support vhost_net lpc_ich radeon tun macvtap mfd_core serio_raw coretemp i2c_algo_bit ttm i5000_edac macvlan drm_kms_helper e1000e edac_core microcode i5k_amb shpchp i2c_i801 drm kvm_intel i2c_core kvm ioatdma dca raid1 >>>>>> [699231.336259] Pid: 8584, comm: modprobe Not tainted 3.6.11-1.fc17.x86_64 #1 >>>>>> [699231.340561] Call Trace: >>>>>> [699231.344865] [<ffffffff8105c8ef>] warn_slowpath_common+0x7f/0xc0 >>>>>> [699231.349212] [<ffffffff8105c9e6>] warn_slowpath_fmt+0x46/0x50 >>>>>> [699231.353595] [<ffffffff812eee52>] __list_del_entry+0x82/0xd0 >>>>>> [699231.357954] [<ffffffff812eeeb1>] list_del+0x11/0x40 >>>>>> [699231.362319] [<ffffffff812f6458>] percpu_counter_destroy+0x28/0x50 >>>>>> [699231.366712] [<ffffffff8114c513>] bdi_destroy+0x43/0x140 >>>>>> [699231.371127] [<ffffffff812be20c>] blk_release_queue+0x8c/0xc0 >>>>>> [699231.375454] [<ffffffff812dc322>] kobject_cleanup+0x82/0x1b0 >>>>>> [699231.379675] [<ffffffff812dc1ab>] kobject_put+0x2b/0x60 >>>>>> [699231.383851] [<ffffffff812b80a5>] blk_put_queue+0x15/0x20 >>>>>> [699231.387899] [<ffffffff812bc659>] blk_cleanup_queue+0xc9/0xe0 >>>>>> [699231.391794] [<ffffffffa01f53f5>] aoedev_freedev+0x135/0x150 [aoe] >>>>>> [699231.395668] [<ffffffffa01f59a5>] aoedev_exit+0x65/0x80 [aoe] >>>>>> [699231.399493] [<ffffffffa01f5afe>] aoe_exit+0x2e/0x40 [aoe] >>>>>> [699231.403273] [<ffffffff810bdefe>] sys_delete_module+0x16e/0x2d0 >>>>>> [699231.407119] [<ffffffff8161db56>] ? __schedule+0x3c6/0x7a0 >>>>>> [699231.411050] [<ffffffff8119054a>] ? sys_write+0x4a/0x90 >>>>>> [699231.415033] [<ffffffff81627329>] system_call_fastpath+0x16/0x1b >>>>>> [699231.419117] ---[ end trace 9e1558af1964b569 ]--- >>>>>> [699231.423248] ------------[ cut here ]------------ >>>>> >>>>> Thanks for the report. The problem seems to be older than that (see >>>>> 2.6.32 below), and it seems to be related to changes that first >>>>> appeared in 2.6.24. I'm going to investigate the changes introduced >>>>> in the commit below to see whether the aoe driver needed updating when >>>>> they went in. I'm Cc-ing Peter Zijlstra in case this rings any bells. >>>> >>>> I highly doubt that has anything to do with it. Since it triggers >>>> immediately on rmmod after modprobe (and not having set a device up, >>>> presumably, being the key), it looks like a generic bug in aoeblk. >>>> >>>> Ed, can you reproduce the issue? >>> >>> Quick guess... >>> >>> >>> diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c >>> index 98f2965..e4473af 100644 >>> --- a/drivers/block/aoe/aoedev.c >>> +++ b/drivers/block/aoe/aoedev.c >>> @@ -280,8 +280,8 @@ freedev(struct aoedev *d) >>> if (d->gd) { >>> aoedisk_rm_sysfs(d); >>> del_gendisk(d->gd); >>> - put_disk(d->gd); >>> blk_cleanup_queue(d->blkq); >>> + put_disk(d->gd); >>> } >>> t = d->targets; >>> e = t + d->ntargets; >> >> Yes, I can reproduce it on 3.5.6. There are devices up, none down, >> when I do rmmod. If no aoe devices are present, the warnings do not >> appear. > > OK, that's good at least. I can try here too. > >> The suggestion above to move put_disk after blk_cleanup_queue doesn't >> affect the list_del warnings, but thanks for the quick guess---Is that >> something we need to change regardless of the issue at hand? > > No should not matter.
Argh. I tried to send the email in a hurry and vger rejected the message as spam because of the HTML subpart. I'll get a process set up for sending replies as clean emails. Meanwhile, my message said,
"Thanks. I think I see the problem. The blk_alloc_queue has already done a bdi_init, and there's no need for aoeblk.c to do it, so when it does, the bdi_stat lists get messed up.
If you think that makes sense and the patch below (corrupted by our MS Exchange email server) also makes sense as a proof of concept, I'll send akpm a proper patch without email corruption. The patch below eliminates the list_del corruption messages in my tests, and I think the mainline aoe driver needs (the cleaned up version of) it as well as older stable kernels."
... and the patch just ifdeffed out the call to bdi_init in aoeblk.c:aoeblk_gdalloc(), along with the associated error handling.
-- Ed Cashin ecashin@coraid.com
| |