From: Govindarajulu Varadarajan <_govind@gmx.com>
To: ssujith@cisco.com, netdev@vger.kernel.org, davem@davemloft.net
Cc: Govindarajulu Varadarajan <_govind@gmx.com>
Subject: [PATCH net 2/2] enic: update desc properly in rx_copybreak
Date: Thu, 6 Nov 2014 15:21:39 +0530 [thread overview]
Message-ID: <1415267499-25955-2-git-send-email-_govind@gmx.com> (raw)
In-Reply-To: <1415267499-25955-1-git-send-email-_govind@gmx.com>
When we reuse the rx buffer, we need to update the desc. If not hardware sees
stale value.
In the following crash, when mtu is changed, hardware sees old rx buffer value
and crashes on skb_put.
Fix this by using enic_queue_rq_desc helper function which updates the necessary
desc.
[ 64.657376] skbuff: skb_over_panic: text:ffffffffa041f55d len:9010 put:9010 head:ffff8800d3ca9fc0 data:ffff8800d3caa000 tail:0x2372 end:0x640 dev:enp0s3
[ 64.659965] ------------[ cut here ]------------
[ 64.661322] kernel BUG at net/core/skbuff.c:100!
[ 64.662644] invalid opcode: 0000 [#1] PREEMPT SMP
[ 64.664001] Modules linked in: rpcsec_gss_krb5 auth_rpcgss oid_registry nfsv4 cirrus ttm drm_kms_helper drm enic psmouse microcode evdev serio_raw syscopyarea sysfillrect sysimgblt i2c_piix4 i2c_core pcspkr nfs lockd grace sunrpc fscache ext4 crc16 mbcache jbd2 sd_mod ata_generic virtio_balloon ata_piix libata uhci_hcd virtio_pci virtio_ring usbcore usb_common virtio scsi_mod
[ 64.664834] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 3.17.0-netnext-10335-g942396b-dirty #273
[ 64.664834] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 64.664834] task: ffffffff81a1d580 ti: ffffffff81a00000 task.ti: ffffffff81a00000
[ 64.664834] RIP: 0010:[<ffffffff81392cf1>] [<ffffffff81392cf1>] skb_panic+0x61/0x70
[ 64.664834] RSP: 0018:ffff880210603d48 EFLAGS: 00010292
[ 64.664834] RAX: 000000000000008c RBX: ffff88020b0f6930 RCX: 0000000000000000
[ 64.664834] RDX: 000000000000008c RSI: ffffffff8178b288 RDI: 00000000ffffffff
[ 64.664834] RBP: ffff880210603d68 R08: 0000000000000001 R09: 0000000000000001
[ 64.664834] R10: 00000000000005ce R11: 0000000000000001 R12: ffff88020b1f0b40
[ 64.664834] R13: 000000000000a332 R14: ffff880209a1a000 R15: 0000000000000001
[ 64.664834] FS: 0000000000000000(0000) GS:ffff880210600000(0000) knlGS:0000000000000000
[ 64.664834] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 64.664834] CR2: 00007f6752935e48 CR3: 0000000035743000 CR4: 00000000000006f0
[ 64.664834] Stack:
[ 64.664834] ffff8800d3caa000 0000000000002372 0000000000000640 ffff88020b1f0000
[ 64.664834] ffff880210603d78 ffffffff81392d54 ffff880210603e08 ffffffffa041f55d
[ 64.664834] 0000000000000296 ffffffff00000000 00008e7e00008e7e ffff880200002332
[ 64.664834] Call Trace:
[ 64.664834] <IRQ>
[ 64.664834]
[ 64.664834] [<ffffffff81392d54>] skb_put+0x54/0x60
[ 64.664834] [<ffffffffa041f55d>] enic_rq_service.constprop.47+0x3ad/0x730 [enic]
[ 64.664834] [<ffffffffa041fa79>] enic_poll_msix_rq+0x199/0x370 [enic]
[ 64.664834] [<ffffffff813a5499>] net_rx_action+0x139/0x210
[ 64.664834] [<ffffffff81290db3>] ? __this_cpu_preempt_check+0x13/0x20
[ 64.664834] [<ffffffff8106110e>] __do_softirq+0x14e/0x280
[ 64.664834] [<ffffffff8106152e>] irq_exit+0x8e/0xb0
[ 64.664834] [<ffffffff8100fd21>] do_IRQ+0x61/0x100
[ 64.664834] [<ffffffff814a2bf2>] common_interrupt+0x72/0x72
fixes: a03bb56e67c357980dae886683733dab5583dc14 ("enic: implement rx_copybreak")
Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com>
---
drivers/net/ethernet/cisco/enic/enic_main.c | 14 ++------------
1 file changed, 2 insertions(+), 12 deletions(-)
diff --git a/drivers/net/ethernet/cisco/enic/enic_main.c b/drivers/net/ethernet/cisco/enic/enic_main.c
index cd254d1..73cf165 100644
--- a/drivers/net/ethernet/cisco/enic/enic_main.c
+++ b/drivers/net/ethernet/cisco/enic/enic_main.c
@@ -940,18 +940,8 @@ static int enic_rq_alloc_buf(struct vnic_rq *rq)
struct vnic_rq_buf *buf = rq->to_use;
if (buf->os_buf) {
- buf = buf->next;
- rq->to_use = buf;
- rq->ring.desc_avail--;
- if ((buf->index & VNIC_RQ_RETURN_RATE) == 0) {
- /* Adding write memory barrier prevents compiler and/or
- * CPU reordering, thus avoiding descriptor posting
- * before descriptor is initialized. Otherwise, hardware
- * can read stale descriptor fields.
- */
- wmb();
- iowrite32(buf->index, &rq->ctrl->posted_index);
- }
+ enic_queue_rq_desc(rq, buf->os_buf, os_buf_index, buf->dma_addr,
+ buf->len);
return 0;
}
--
2.1.0
next prev parent reply other threads:[~2014-11-06 9:52 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-06 9:51 [PATCH net 1/2] enic: handle error condition properly in enic_rq_indicate_buf Govindarajulu Varadarajan
2014-11-06 9:51 ` Govindarajulu Varadarajan [this message]
2014-11-06 21:42 ` [PATCH net 2/2] enic: update desc properly in rx_copybreak David Miller
2014-11-06 21:42 ` [PATCH net 1/2] enic: handle error condition properly in enic_rq_indicate_buf 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=1415267499-25955-2-git-send-email-_govind@gmx.com \
--to=_govind@gmx.com \
--cc=davem@davemloft.net \
--cc=netdev@vger.kernel.org \
--cc=ssujith@cisco.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).