Subject: Hang: 2.6.32.4 sky2/DMAR (was [PATCH] sky2: Fix WARNING: at lib/dma-debug.c:902 check_sync)

From: Michael Breuer <[email-masked]>
Date: Fri, 22 Jan 2010 13:01:15 -0500

Kernel 2.6.32.4 (git) with the following patches applied:

af_packet.c (tpacket_snd version 3)
sky2.c pskb_may_pull
sky2 fix WARNING at lib/dma-debug.c check_sync

Running with CONFIG_DMAR=n, system is stable.
Running with the exact same source but CONFIG_DMAR=y I get the WARNING 
(see below) after about 36 hours of uptime (has varied from about 24 to 
about 48):
Smolt profile: 
http://smolt.fedoraproject.org/show?uuid=pub_bb05c701-1e47-4b3c-9fab-54f520f39d79+
I'm also attaching dmesg.old (dmesg from the crash).

Subsequent to this the system watchdog reboots the system (it's hung).

Of interest: each and every time this has happened the system was under 
heavy RX load (win7 backup to a cifs share hosted on this server). Also, 
there is always a dhcp exchange of some sort preceding the event.

It is possible that the event is re creatable without DMAR enabled, but 
I have been unsuccessful in doing so.

Jan 22 05:38:36 mail dhcpd: DHCPREQUEST for 10.0.0.54 from 
00:1b:78:c8:2b:8e (HPC82B8D) via eth0
Jan 22 05:38:36 mail dhcpd: DHCPACK on 10.0.0.54 to 00:1b:78:c8:2b:8e 
(HPC82B8D) via eth0
Jan 22 05:38:41 mail kernel: DRHD: handling fault status reg 2
Jan 22 05:38:41 mail kernel: DMAR:[DMA Read] Request device [06:00.0] 
fault addr ffdfdd9fe000
Jan 22 05:38:41 mail kernel: DMAR:[fault reason 06] PTE Read access is 
not set
Jan 22 05:38:41 mail kernel: sky2 0000:06:00.0: error interrupt 
status=0xc0000000
Jan 22 05:38:41 mail kernel: sky2 0000:06:00.0: PCI hardware error (0x2010)
Jan 22 05:39:18 mail kernel: ------------[ cut here ]------------
Jan 22 05:39:18 mail kernel: WARNING: at net/sched/sch_generic.c:261 
dev_watchdog+0xf3/0x164()
Jan 22 05:39:18 mail kernel: Hardware name: System Product Name
Jan 22 05:39:18 mail kernel: NETDEV WATCHDOG: eth0 (sky2): transmit 
queue 0 timed out
Jan 22 05:39:18 mail kernel: Modules linked in: cpufreq_stats 
ip6table_mangle ip6table_filter ip6_tables ipt_MASQUERADE iptable_nat 
nf_nat iptable_mangle iptable_raw appletalk psnap llc nfsd lockd nfs_acl 
auth_rpcgss exportfs hwmon_vid coretemp sunrpc acpi_cpufreq sit tunnel4 
ipt_LOG nf_conntrack_netbios_ns nf_conntrack_ftp nf_conntrack_ipv6 
xt_multiport xt_DSCP xt_dscp xt_MARK ipv6 dm_multipath kvm_intel kvm 
snd_hda_codec_analog snd_ens1371 gameport snd_rawmidi snd_hda_intel 
snd_ac97_codec snd_hda_codec snd_hwdep ac97_bus snd_seq snd_seq_device 
firewire_ohci snd_pcm firewire_core crc_itu_t snd_timer snd 
gspca_spca505 gspca_main i2c_i801 videodev v4l1_compat sky2 soundcore 
v4l2_compat_ioctl32 wmi snd_page_alloc asus_atk0110 hwmon pcspkr 
iTCO_wdt iTCO_vendor_support fbcon tileblit font bitblit softcursor 
raid456 async_raid6_recov async_pq raid6_pq async_xor xor async_memcpy 
async_tx raid1 ata_generic pata_acpi pata_marvell nouveau ttm 
drm_kms_helper drm agpgart fb i2c_algo_bit cfbcopyarea i2c_core 
cfbimgblt cfb
Jan 22 05:39:18 mail kernel: fillrect [last unloaded: microcode]
Jan 22 05:39:18 mail kernel: Pid: 0, comm: swapper Tainted: G        W  
2.6.32.4MMAPDMARAF3SKY2PSKBMAYPULL-00912-g914160d-dirty #6
Jan 22 05:39:18 mail kernel: Call Trace:
Jan 22 05:39:18 mail kernel: <IRQ>  [<ffffffff810536ee>] 
warn_slowpath_common+0x7c/0x94
Jan 22 05:39:18 mail kernel: [<ffffffff8105375d>] 
warn_slowpath_fmt+0x41/0x43
Jan 22 05:39:18 mail kernel: [<ffffffff813e3b6b>] ? netif_tx_lock+0x44/0x6c
Jan 22 05:39:18 mail kernel: [<ffffffff813e3cd3>] dev_watchdog+0xf3/0x164
Jan 22 05:39:18 mail kernel: [<ffffffff8105f3f4>] ? cascade+0x6a/0x84
Jan 22 05:39:18 mail kernel: [<ffffffff8106323f>] 
run_timer_softirq+0x1c8/0x270
Jan 22 05:39:18 mail kernel: [<ffffffff8105af0f>] __do_softirq+0xf8/0x1cd
Jan 22 05:39:18 mail kernel: [<ffffffff8107f0ab>] ? 
tick_program_event+0x2a/0x2c
Jan 22 05:39:18 mail kernel: [<ffffffff81012e1c>] call_softirq+0x1c/0x30
Jan 22 05:39:18 mail kernel: [<ffffffff810143a3>] do_softirq+0x4b/0xa6
Jan 22 05:39:18 mail kernel: [<ffffffff8105aaef>] irq_exit+0x4a/0x8c
Jan 22 05:39:18 mail kernel: [<ffffffff81470612>] 
smp_apic_timer_interrupt+0x86/0x94
Jan 22 05:39:18 mail kernel: [<ffffffff810127e3>] 
apic_timer_interrupt+0x13/0x20
Jan 22 05:39:18 mail kernel: <EOI>  [<ffffffff812c729a>] ? 
acpi_idle_enter_bm+0x256/0x28a
Jan 22 05:39:18 mail kernel: [<ffffffff812c7293>] ? 
acpi_idle_enter_bm+0x24f/0x28a
Jan 22 05:39:18 mail kernel: [<ffffffff813a6c3c>] ? 
cpuidle_idle_call+0x9e/0xfa
Jan 22 05:39:18 mail kernel: [<ffffffff81010c90>] ? cpu_idle+0xb4/0xf6
Jan 22 05:39:18 mail kernel: [<ffffffff81465ba5>] ? 
start_secondary+0x201/0x242
Jan 22 05:39:18 mail kernel: ---[ end trace 57f7151f6a5def07 ]---
Jan 22 05:39:18 mail kernel: sky2 eth0: tx timeout
Jan 22 05:39:18 mail kernel: sky2 eth0: transmit ring 76 .. 35 report=76 
done=76
Jan 22 05:39:18 mail kernel: sky2 eth0: disabling interface
Jan 22 05:39:18 mail kernel: sky2 eth0: enabling interface
Jan 22 05:39:21 mail kernel: sky2 eth0: Link is up at 1000 Mbps, full 
duplex, flow control both
Jan 22 05:40:06 mail kernel: sky2 eth0: tx timeout
Jan 22 05:40:06 mail kernel: sky2 eth0: transmit ring 3 .. 90 report=3 
done=3
Jan 22 05:40:06 mail kernel: sky2 eth0: disabling interface
Jan 22 05:40:06 mail kernel: sky2 eth0: enabling interface
Jan 22 05:40:09 mail kernel: sky2 eth0: Link is up at 1000 Mbps, full 
duplex, flow control both
Jan 22 05:40:30 mail abrt: Kerneloops: Reported 1 kernel oopses to Abrt
Jan 22 05:40:30 mail abrtd: Directory 'kerneloops-1264156830-1' creation 
detected
Jan 22 05:40:30 mail abrtd: Can't open file 
'/var/cache/abrt/kerneloops-1264156830-1/cmdline'
Jan 22 05:40:30 mail abrtd: Corrupted or bad crash, deleting
Jan 22 05:40:33 mail dhcpd: DHCPINFORM from 10.0.0.11 via eth0
Jan 22 05:40:33 mail dhcpd: DHCPACK to 10.0.0.11 (00:1a:92:8d:30:81) via 
eth0
Jan 22 05:40:36 mail dhcpd: DHCPINFORM from 10.0.0.11 via eth0
Jan 22 05:40:36 mail dhcpd: DHCPACK to 10.0.0.11 (00:1a:92:8d:30:81) via 
eth0
Jan 22 05:40:50 mail named[11245]: error (connection refused) resolving 
'173-212-207-86.hostnoc.net/A/IN': 2607:f878:0:3::12#53
Jan 22 05:40:50 mail named[11245]: error (connection refused) resolving 
'NS1.HOSTNOC.NET/AAAA/IN': 2607:f878:0:3::10#53
<watchdog reboot>