linux/drivers/net
Iyappan Subramanian ecf6ba83d7 drivers: net: xgene: fix: Out of order descriptor bytes read
This patch fixes the following kernel crash,

	WARNING: CPU: 2 PID: 0 at net/ipv4/tcp_input.c:3079 tcp_clean_rtx_queue+0x658/0x80c()
	Call trace:
	[<fffffe0000096b7c>] dump_backtrace+0x0/0x184
	[<fffffe0000096d10>] show_stack+0x10/0x1c
	[<fffffe0000685ea0>] dump_stack+0x74/0x98
	[<fffffe00000b44e0>] warn_slowpath_common+0x88/0xb0
	[<fffffe00000b461c>] warn_slowpath_null+0x14/0x20
	[<fffffe00005b5c1c>] tcp_clean_rtx_queue+0x654/0x80c
	[<fffffe00005b6228>] tcp_ack+0x454/0x688
	[<fffffe00005b6ca8>] tcp_rcv_established+0x4a4/0x62c
	[<fffffe00005bf4b4>] tcp_v4_do_rcv+0x16c/0x350
	[<fffffe00005c225c>] tcp_v4_rcv+0x8e8/0x904
	[<fffffe000059d470>] ip_local_deliver_finish+0x100/0x26c
	[<fffffe000059dad8>] ip_local_deliver+0xac/0xc4
	[<fffffe000059d6c4>] ip_rcv_finish+0xe8/0x328
	[<fffffe000059dd3c>] ip_rcv+0x24c/0x38c
	[<fffffe0000563950>] __netif_receive_skb_core+0x29c/0x7c8
	[<fffffe0000563ea4>] __netif_receive_skb+0x28/0x7c
	[<fffffe0000563f54>] netif_receive_skb_internal+0x5c/0xe0
	[<fffffe0000564810>] napi_gro_receive+0xb4/0x110
	[<fffffe0000482a2c>] xgene_enet_process_ring+0x144/0x338
	[<fffffe0000482d18>] xgene_enet_napi+0x1c/0x50
	[<fffffe0000565454>] net_rx_action+0x154/0x228
	[<fffffe00000b804c>] __do_softirq+0x110/0x28c
	[<fffffe00000b8424>] irq_exit+0x8c/0xc0
	[<fffffe0000093898>] handle_IRQ+0x44/0xa8
	[<fffffe000009032c>] gic_handle_irq+0x38/0x7c
	[...]

Software writes poison data into the descriptor bytes[15:8] and upon
receiving the interrupt, if those bytes are overwritten by the hardware with
the valid data, software also reads bytes[7:0] and executes receive/tx
completion logic.

If the CPU executes the above two reads in out of order fashion, then the
bytes[7:0] will have older data and causing the kernel panic.  We have to
force the order of the reads and thus this patch introduces read memory
barrier between these reads.

Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Signed-off-by: Keyur Chudgar <kchudgar@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-30 18:17:31 -08:00
..
appletalk net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
arcnet ARCNET: enable eae arcnet card support 2014-09-29 14:36:26 -04:00
bonding bonding: change error message to debug message in __bond_release_one() 2014-12-27 02:20:55 -05:00
caif caif: remove wrong dev_net_set() call 2015-01-29 14:20:02 -08:00
can can: kvaser_usb: Fix state handling upon BUS_ERROR events 2015-01-27 08:55:09 +01:00
cris
dsa net: dsa: bcm_sf2: always select FIXED_PHY 2014-12-16 00:57:07 -05:00
ethernet drivers: net: xgene: fix: Out of order descriptor bytes read 2015-01-30 18:17:31 -08:00
fddi defxx: Clean up DEFEA resource management 2014-11-21 16:37:13 -05:00
hamradio hamradio: 6pack: remove unnecessary check 2014-11-03 15:34:31 -05:00
hippi
hyperv hyperv: Fix some variable name typos in send-buffer init/revoke 2014-12-22 16:11:11 -05:00
ieee802154 Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
ipvlan ipvlan: fix incorrect usage of IS_ERR() macro in IPv6 code path. 2015-01-25 00:24:19 -08:00
irda Driver core patches for 3.19-rc1 2014-12-14 16:10:09 -08:00
phy net: phy: micrel: use generic config_init for KSZ8021/KSZ8031 2014-12-26 16:19:50 -05:00
plip
ppp ppp: deflate: never return len larger than output buffer 2015-01-29 14:50:01 -08:00
slip
team team: avoid possible underflow of count_pending value for notify_peers and mcast_rejoin 2015-01-14 16:53:57 -05:00
usb r8152: remove sram_read 2015-01-19 16:16:32 -05:00
vmxnet3 ethtool: Support for configurable RSS hash function 2014-12-08 21:07:10 -05:00
wan net: wan: add missing virt_to_bus dependencies 2015-01-29 15:08:21 -08:00
wimax kbuild: remove unnecessary "obj- := dummy.o" trick 2014-10-02 13:55:02 +02:00
wireless ath9k: fix race condition in irq processing during hardware reset 2015-01-19 14:32:29 +02:00
xen-netback xen-netback: fixing the propagation of the transmit shaper timeout 2015-01-06 14:17:37 -05:00
dummy.c dummy: use MODULE_VERSION 2014-12-09 21:51:06 -05:00
eql.c net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
ifb.c net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
Kconfig ipvlan: ipvlan depends on INET and IPV6 2014-11-29 20:53:05 -08:00
LICENSE.SRC
loopback.c net: better IFF_XMIT_DST_RELEASE support 2014-10-07 13:22:11 -04:00
macvlan.c macvlan: play well with ipvlan device 2014-12-09 16:10:06 -05:00
macvtap.c macvtap: drop broken IFF_VNET_LE 2014-12-16 11:19:42 -05:00
Makefile ipvlan: Initial check-in of the IPVLAN driver. 2014-11-24 15:29:18 -05:00
mdio.c
mii.c
netconsole.c
nlmon.c
ntb_netdev.c
rionet.c
sb1000.c
Space.c
sungem_phy.c
tun.c tun: drop broken IFF_VNET_LE 2014-12-16 11:19:41 -05:00
veth.c
virtio_net.c virtio_net: Fix napi poll list corruption 2014-12-22 16:10:12 -05:00
vxlan.c vxlan: setup the right link netns in newlink hdlr 2015-01-29 14:20:02 -08:00
xen-netfront.c xen-netfront: use different locks for Rx and Tx stats 2015-01-13 17:22:11 -05:00