New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
FS#1905 - Kernel bug: brcm47xx/mips74k reboots after: bgmac_bcma bcma0:1 eth0: Found oversized packet... #6626
Comments
xback: Does this also occur on the latest 18.06 or master states? Thanks. |
DmitryErshov: Sorry, I'm afraid to brick the router and check only the stable release 18.06.1 now. |
yarda: I am not sure whether I am also affected by this, because I have different crashlog, but the reproducer is the same - just running speedtest.net and the router reboots. I have 18.06.1 @ Asus Wl-500gp. The reboot can happen dozen of times per day which is really annoying. I will try downgrading to 17 release. My crashlog: <1>[ 665.717726] Data bus error, epc == 8000cb10, ra == 80005ff4 |
yarda: I downgraded to 17.01.6 and it seems it works, i.e. it no more reboots when running speedtest.net. |
yarda: Sorry for noise in my case it's https://dev.archive.openwrt.org/ticket/11091 |
DmitryErshov: Jaroslav Škarvada, thank you for the info and ticket. I just attach another two more crashlogs for comparison. |
yarda: Hmm, I don't see the 'Found oversized packet at slot' in the log. It's probably because your device uses BGMAC_BCMA and mine b44 driver. Maybe it's related (e.g. the core of the problem lies somewhere higher and is common for BRCM SoCs) and maybe it is completely unrelated problem (I cannot judge at the moment). The fact is that mine device starts rebooting under heavy network load on the WAN which even the speedtest.net can trigger (the 17.01.6 seems a bit more stable for me, but the problem still occurs). I temporally workaround the problem by shaping the WAN speed to 20 MBit. I am going to bisect, because it worked OK with the ancient 2.4 kernels and I have some reports that it also worked with some 2.6 kernels. I will probably open another bug report for it (because the archived ticket 11091 seems no longer valid). |
kizmoo: I have a similar problem with OpenWrt 18.06.2 on brcm47xx. 100% Reboot after iperf3 with simultaneous connections. For example:
The effect is immediate in my case. On router wgt634u [[https://bugs.openwrt.org/index.php?do=details&task_id=126|ticket ID 126]] |
DmitryErshov:
==== Device ====
==== OpenWrt version ====
Stable Release OpenWrt 18.06.1
# cat /etc/openwrt_release DISTRIB_ID='OpenWrt' DISTRIB_RELEASE='18.06.1' DISTRIB_REVISION='r7258-5eb055306f' DISTRIB_TARGET='brcm47xx/mips74k' DISTRIB_ARCH='mipsel_74kc' DISTRIB_DESCRIPTION='OpenWrt 18.06.1 r7258-5eb055306f' DISTRIB_TAINTS=''
Linux OpenWrt 4.14.63 #0 Wed Aug 15 20:42:39 2018 mips GNU/Linux
==== What does it do that it should not do ====
Sometimes the router hangup and reboots.
This can happen several times a day.
The log contains entries:
Oct 22 12:50:50 OpenWrt kernel: [249137.210802] bgmac_bcma bcma0:1 eth0: Found oversized packet at slot 56, DMA issue! Oct 22 12:50:50 OpenWrt kernel: [249137.254221] bgmac_bcma bcma0:1 eth0: Found oversized packet at slot 121, DMA issue! Oct 22 12:50:50 OpenWrt kernel: [249137.295788] bgmac_bcma bcma0:1 eth0: Found oversized packet at slot 314, DMA issue! Oct 22 12:50:50 OpenWrt kernel: [249137.320500] bgmac_bcma bcma0:1 eth0: Found oversized packet at slot 509, DMA issue!
Few entries from crashlog:
<3>[249137.254221] bgmac_bcma bcma0:1 eth0: Found oversized packet at slot 121, DMA issue!
<3>[249137.295788] bgmac_bcma bcma0:1 eth0: Found oversized packet at slot 314, DMA issue!
<3>[249137.320500] bgmac_bcma bcma0:1 eth0: Found oversized packet at slot 509, DMA issue!
<0>[249137.334933] skbuff: skb_over_panic: text:80238000 len:1753 put:1753 head:86862a80 data:86862a80 tail:0x86863159 end:0x868630e0 dev:
<4>[249137.347856] Kernel bug detected[#1]:
<4>[249137.351653] CPU: 0 PID: 7 Comm: ksoftirqd/0 Tainted: G W 4.14.63 #0
Full crashlog attached.
==== Steps to reproduce ====
To reproduce the bug I try to fill the nf_conntrack table with thousands of connections.
Several seconds it was kept filled:
net.netfilter.nf_conntrack_max = 16384
net.netfilter.nf_conntrack_count = 16383
log:
nf_conntrack: nf_conntrack: table full, dropping packet
nf_conntrack: nf_conntrack: table full, dropping packet
...
then several messages:
bgmac_bcma bcma0:1 eth0: Found oversized packet at slot 262, DMA issue!
...
and the router rebooted.
==== Another way to reproduce... ====
...same error messages in the log - run bandwidth test [[http://www.speedtest.net]]
...
Oct 22 14:46:08 OpenWrt kernel: [ 6908.757065] bgmac_bcma bcma0:1 eth0: Found oversized packet at slot 118, DMA issue!
Oct 22 14:46:08 OpenWrt kernel: [ 6908.770969] bgmac_bcma bcma0:1 eth0: Found oversized packet at slot 183, DMA issue!
Oct 22 14:46:08 OpenWrt kernel: [ 6908.800488] bgmac_bcma bcma0:1 eth0: Found oversized packet at slot 442, DMA issue!
==== What I have already done to workaround/fix the problem ====
I try to decrease value of the nf_conntrack_tcp_timeout_established
from
net.netfilter.nf_conntrack_tcp_timeout_established = 7440
to
net.netfilter.nf_conntrack_tcp_timeout_established = 900
typical value:
net.netfilter.nf_conntrack_count = 5130 (...7000)
but it still reboots sometimes.
==== Additional info ====
The text was updated successfully, but these errors were encountered: