linux_dsm_epyc7002/drivers/net
Johannes Berg c7df1f4bda iwlwifi: pcie: rework RX buffer list init and freeing
The PCIe code has an array of buffer descriptors (RXBs) that have pages
and DMA mappings attached. In regular use, the array isn't used and the
buffers are either on the hardware receive queue or the rx_free/rx_used
lists for recycling.

Occasionally, during module unload, we'd see a warning from this:

WARNING: at lib/list_debug.c:32 __list_add+0x91/0xa0()
list_add corruption. prev->next should be next (c31c98cc), but was c31c80bc. (prev=c31c80bc).
Pid: 519, comm: rmmod Tainted: G        W  O 3.4.24-dev #3
Call Trace:
 [<c10335b2>] warn_slowpath_common+0x72/0xa0
 [<c1033683>] warn_slowpath_fmt+0x33/0x40
 [<c12e31d1>] __list_add+0x91/0xa0
 [<fdf2083c>] iwl_pcie_rxq_free_rbs+0xcc/0xe0 [iwlwifi]
 [<fdf21b3f>] iwl_pcie_rx_free+0x3f/0x210 [iwlwifi]
 [<fdf2dd7a>] iwl_trans_pcie_free+0x2a/0x90 [iwlwifi]

The reason for this seems to be that in iwl_pcie_rxq_free_rbs() we use
the array to free all buffers (the hardware receive queue isn't in use
any more at this point). The function also adds all buffers to rx_used
because it's also used during initialisation (when no freeing happens.)
This can cause the warning because it may add entries to the list that
are already on it. Luckily, this is harmless because it can only happen
when the entire data structure is freed anyway, since during init both
lists are initialized from scratch.

Disentangle this code and treat init and free separately. During init
we just need to put them onto the list after freeing all buffers (for
switching between 4k/8k buffers); during free no list manipulations
are necessary at all.

Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-06-25 12:13:54 +02:00
..
appletalk
arcnet
bonding Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-05-01 17:51:54 -07:00
caif Lots of virtio work which wasn't quite ready for last merge window. Plus 2013-05-02 14:14:04 -07:00
can Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-05-01 14:08:52 -07:00
cris
dsa
ethernet Merge branch 'stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile 2013-05-09 14:34:58 -07:00
fddi
hamradio drivers/net: rename random32() to prandom_u32() 2013-05-07 18:38:27 -07:00
hippi
hyperv hyperv: Fix a compiler warning in netvsc_send() 2013-04-29 14:06:32 -04:00
ieee802154 at86rf230: change irq handling to prevent lockups with edge type irq 2013-04-16 16:34:08 -04:00
irda net/irda: fix error return code in bfin_sir_open() 2013-05-08 13:13:29 -07:00
phy Removal of GENERIC_GPIO for v3.10 2013-05-09 09:59:16 -07:00
plip net: add ETH_P_802_3_MIN 2013-03-28 01:20:42 -04:00
ppp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-05-01 14:08:52 -07:00
slip
team drivers/net: rename random32() to prandom_u32() 2013-05-07 18:38:27 -07:00
usb sierra_net: keep status interrupt URB active 2013-05-08 13:13:29 -07:00
vmxnet3 net: vlan: add protocol argument to packet tagging functions 2013-04-19 14:46:06 -04:00
wan
wimax
wireless iwlwifi: pcie: rework RX buffer list init and freeing 2013-06-25 12:13:54 +02:00
xen-netback xen-netback: better names for thresholds 2013-05-02 16:50:08 -04:00
dummy.c
eql.c
ifb.c net: vlan: announce STAG offload capability in some drivers 2013-04-19 14:46:06 -04:00
Kconfig VXLAN: Fix vxlan stats handling. 2013-03-26 12:27:18 -04:00
LICENSE.SRC
loopback.c
macvlan.c net: vlan: announce STAG offload capability in some drivers 2013-04-19 14:46:06 -04:00
macvtap.c net: switch to use skb_probe_transport_header() 2013-03-27 12:48:31 -04:00
Makefile
mdio.c
mii.c
netconsole.c
ntb_netdev.c
rionet.c
sb1000.c
Space.c
sungem_phy.c
tun.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-30 03:55:20 -04:00
veth.c net: vlan: announce STAG offload capability in some drivers 2013-04-19 14:46:06 -04:00
virtio_net.c Lots of virtio work which wasn't quite ready for last merge window. Plus 2013-05-02 14:14:04 -07:00
vxlan.c vxlan: do not set SKB_GSO_UDP 2013-04-29 15:27:47 -04:00
xen-netfront.c xen-netfront: reduce gso_max_size to account for max TCP header 2013-04-22 15:37:01 -04:00