2015-08-21 08:03:08

by Varka Bhadram

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Subject: Fwd: Memory leak issue in ath9k

---------- Forwarded message ----------
From: Raghavendra Rao <[email protected]>
Date: Fri, Aug 21, 2015 at 1:05 PM
Subject: Memory leak issue in ath9k
To: [email protected]
Cc: [email protected], Varka Bhadram <[email protected]>


Hello,

Currently we are facing a memory leak problem while receiving the
packets over ath9k.

Here is the setup:
Board : Gateworks-54xx
SoC : imx6q, 900MHz
RAM : 1GB
WiFi Module : ath9k (AR5BHB112)

The board is currently receiving packets at the rate of 1 packet for
every 1 ms. At this rate, after some time, the kernel panics and
throws the following error:
ath: skbuff alloc of size 1974 failed

We have checked the same issue using kmemleak utility, and found the
following as its output for every received packet:

unreferenced object 0xa2bf1b40 (size 192):
comm "softirq", pid 0, jiffies 70621 (age 4074.356s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 0c e4 1c 27 43 65 fc 13 ...........'Ce..
00 00 00 00 00 a0 ae bd 00 00 00 00 00 00 00 00 ................
backtrace:
[<80823bac>] kmemleak_alloc+0x68/0xcc
[<8013ce5c>] kmem_cache_alloc+0x1b4/0x2d4
[<8064f878>] build_skb+0x34/0xbc
[<80652a34>] __alloc_rx_skb+0x90/0xfc
[<80652b1c>] __netdev_alloc_skb+0x28/0x50
[<80525cf8>] ath_rxbuf_alloc+0x30/0x88
[<804f15b8>] ath_rx_tasklet+0x394/0xac0
[<804ef378>] ath9k_tasklet+0xf8/0x214
[<800316e8>] tasklet_action+0x8c/0x13c
[<80030900>] __do_softirq+0x114/0x454
[<80030fc4>] irq_exit+0xcc/0x140
[<8007b780>] __handle_domain_irq+0x7c/0xe8
[<800087e4>] gic_handle_irq+0x30/0x70
[<800140a4>] __irq_svc+0x44/0x5c
[<80010494>] arch_cpu_idle+0x30/0x4c
[<80065cc4>] cpu_startup_entry+0x17c/0x2f0

and also the following in the dmesg :
kmemleak: 104107 new suspected memory leaks (see /sys/kernel/debug/kmemleak)

Kindly address this issue, and provide the cause and solution to this.

Thanks and Regards,
Raghavendra



--
Thanks and Regards,
Varka Bhadram.


2015-08-21 09:27:25

by Bastian Bittorf

[permalink] [raw]
Subject: Re: Fwd: Memory leak issue in ath9k

* Varka Bhadram <[email protected]> [21.08.2015 10:52]:
> ath: skbuff alloc of size 1974 failed

i have seen this issue some month ago:
https://dev.openwrt.org/ticket/14782

how old - or better: which exact version
(kernel/ath9k) you are running?

bye, bastian