netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: <sean.wang@mediatek.com>
To: <john@phrozen.org>, <davem@davemloft.net>
Cc: <nbd@openwrt.org>, <netdev@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>,
	<linux-mediatek@lists.infradead.org>, <keyhaede@gmail.com>,
	Sean Wang <sean.wang@mediatek.com>
Subject: [PATCH v2 net 0/2] Fix crash caused by reporting inconsistent skb->len to BQL
Date: Fri, 14 Apr 2017 11:19:10 +0800	[thread overview]
Message-ID: <1492139952-8104-1-git-send-email-sean.wang@mediatek.com> (raw)

From: Sean Wang <sean.wang@mediatek.com>

Changes since v1:
- fix inconsistent enumeration which easily causes the potential bug

The series fixes kernel BUG caused by inconsistent SKB length reported
into BQL. The reason for inconsistent length comes from hardware BUG which
results in different port number carried on the TXD within the lifecycle of
SKB. So patch 2) is proposed for use a software way to track which port
the SKB involving instead of hardware way. And patch 1) is given for another
issue I found which causes TXD and SKB inconsistency that is not expected
in the initial logic, so it is also being corrected it in the series.

The log for the kernel BUG caused by the issue is posted as below.

[  120.825955] kernel BUG at ... lib/dynamic_queue_limits.c:26!
[  120.837684] Internal error: Oops - BUG: 0 [#1] SMP ARM
[  120.842778] Modules linked in:
[  120.845811] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.11.0-rc1-191576-gdbcef47 #35
[  120.853488] Hardware name: Mediatek Cortex-A7 (Device Tree)
[  120.859012] task: c1007480 task.stack: c1000000
[  120.863510] PC is at dql_completed+0x108/0x17c
[  120.867915] LR is at 0x46
[  120.870512] pc : [<c03c19c8>]    lr : [<00000046>]    psr: 80000113
[  120.870512] sp : c1001d58  ip : c1001d80  fp : c1001d7c
[  120.881895] r10: 0000003e  r9 : df6b3400  r8 : 0ed86506
[  120.887075] r7 : 00000001  r6 : 00000001  r5 : 0ed8654c  r4 : df0135d8
[  120.893546] r3 : 00000001  r2 : df016800  r1 : 0000fece  r0 : df6b3480
[  120.900018] Flags: Nzcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
[  120.907093] Control: 10c5387d  Table: 9e27806a  DAC: 00000051
[  120.912789] Process swapper/0 (pid: 0, stack limit = 0xc1000218)
[  120.918744] Stack: (0xc1001d58 to 0xc1002000)

....

121.085331] 1fc0: 00000000 c0a52a28 00000000 c10855d4 c1003c58 c0a52a24 c100885c 8000406a
[  121.093444] 1fe0: 410fc073 00000000 00000000 c1001ff8 8000807c c0a009cc 00000000 00000000
[  121.101575] [<c03c19c8>] (dql_completed) from [<c04cb010>] (mtk_napi_tx+0x1d0/0x37c)
[  121.109263] [<c04cb010>] (mtk_napi_tx) from [<c05e28cc>] (net_rx_action+0x24c/0x3b8)
[  121.116951] [<c05e28cc>] (net_rx_action) from [<c010152c>] (__do_softirq+0xe4/0x35c)
[  121.124638] [<c010152c>] (__do_softirq) from [<c012a624>] (irq_exit+0xe8/0x150)
[  121.131895] [<c012a624>] (irq_exit) from [<c017750c>] (__handle_domain_irq+0x70/0xc4)
[  121.139666] [<c017750c>] (__handle_domain_irq) from [<c0101404>] (gic_handle_irq+0x58/0x9c)
[  121.147953] [<c0101404>] (gic_handle_irq) from [<c010e18c>] (__irq_svc+0x6c/0x90)
[  121.155373] Exception stack(0xc1001ef8 to 0xc1001f40)

Sean Wang (2):
  net: ethernet: mediatek: fix inconsistency between TXD and the used
    buffer
  net: ethernet: mediatek: fix inconsistency of port number carried in
    TXD

 drivers/net/ethernet/mediatek/mtk_eth_soc.c | 31 ++++++++++++++++-------------
 drivers/net/ethernet/mediatek/mtk_eth_soc.h | 12 ++++++++---
 2 files changed, 26 insertions(+), 17 deletions(-)

-- 
1.9.1

             reply	other threads:[~2017-04-14  3:19 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-04-14  3:19 sean.wang [this message]
2017-04-14  3:19 ` [PATCH v2 net 1/2] net: ethernet: mediatek: fix inconsistency between TXD and the used buffer sean.wang
2017-04-14  3:19 ` [PATCH v2 net 2/2] net: ethernet: mediatek: fix inconsistency of port number carried in TXD sean.wang
2017-04-17 17:34 ` [PATCH v2 net 0/2] Fix crash caused by reporting inconsistent skb->len to BQL David Miller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1492139952-8104-1-git-send-email-sean.wang@mediatek.com \
    --to=sean.wang@mediatek.com \
    --cc=davem@davemloft.net \
    --cc=john@phrozen.org \
    --cc=keyhaede@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mediatek@lists.infradead.org \
    --cc=nbd@openwrt.org \
    --cc=netdev@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).