netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: netdev@vger.kernel.org
Cc: Divy Le Ray <divy@chelsio.com>, Vipul Pandya <vipul@chelsio.com>,
	Jay Hernandez <jay@chelsio.com>,
	Gavin Shan <shangw@linux.vnet.ibm.com>
Subject: [PATCH] cxgb3: Missing rtnl lock in error recovery
Date: Sun, 30 Jun 2013 14:37:11 +1000	[thread overview]
Message-ID: <1372567031.18612.94.camel@pasglop> (raw)

When exercising error injection on IBM pseries machine, I hit the
following warning:

[  251.450043] RTAS: event: 89, Type: Platform Error, Severity: 2
[  253.549822] cxgb3 0006:01:00.0: enabling device (0140 -> 0142)
[  253.713560] cxgb3 0006:01:00.0: adapter recovering, PEX ERR 0x100
[  254.895437] RTNL: assertion failed at net/core/dev.c (2031)
[  254.895467] CPU: 6 PID: 5449 Comm: eehd Tainted: G        W    3.10.0-rc7-00157-gea461ab #19
[  254.895474] Call Trace:
[  254.895483] [c000000fac56f7d0] [c000000000014dcc] .show_stack+0x7c/0x1f0 (unreliable)
[  254.895493] [c000000fac56f8a0] [c0000000007ba318] .dump_stack+0x28/0x3c
[  254.895500] [c000000fac56f910] [c0000000006c0384] .netif_set_real_num_tx_queues+0x224/0x230
[  254.895515] [c000000fac56f9b0] [d00000000ef35510] .cxgb_open+0x80/0x3f0 [cxgb3]
[  254.895525] [c000000fac56fa50] [d00000000ef35914] .t3_resume_ports+0x94/0x100 [cxgb3]
[  254.895533] [c000000fac56fae0] [c00000000005fc8c] .eeh_report_resume+0x8c/0xd0
[  254.895539] [c000000fac56fb60] [c00000000005e9fc] .eeh_pe_dev_traverse+0x9c/0x190
[  254.895545] [c000000fac56fc10] [c000000000060000] .eeh_handle_event+0x110/0x330
[  254.895551] [c000000fac56fca0] [c000000000060350] .eeh_event_handler+0x130/0x1a0
[  254.895558] [c000000fac56fd30] [c0000000000ad758] .kthread+0xe8/0xf0
[  254.895566] [c000000fac56fe30] [c00000000000a05c] .ret_from_kernel_thread+0x5c/0x80

It appears that t3_resume_ports() is called with the rtnl_lock held from
the fatal error task but not from the PCI error callbacks. This fixes it.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org>
---

diff --git a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
index 71497e8..b650951 100644
--- a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
@@ -3037,7 +3037,9 @@ static void t3_io_resume(struct pci_dev *pdev)
 	CH_ALERT(adapter, "adapter recovering, PEX ERR 0x%x\n",
 		 t3_read_reg(adapter, A_PCIE_PEX_ERR));
 
+	rtnl_lock();
 	t3_resume_ports(adapter);
+	rtnl_unlock();
 }
 
 static const struct pci_error_handlers t3_err_handler = {

             reply	other threads:[~2013-06-30  4:37 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-06-30  4:37 Benjamin Herrenschmidt [this message]
2013-07-02 19:38 ` [PATCH] cxgb3: Missing rtnl lock in error recovery 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=1372567031.18612.94.camel@pasglop \
    --to=benh@kernel.crashing.org \
    --cc=divy@chelsio.com \
    --cc=jay@chelsio.com \
    --cc=netdev@vger.kernel.org \
    --cc=shangw@linux.vnet.ibm.com \
    --cc=vipul@chelsio.com \
    /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).