Commit Graph

769162 Commits

Author SHA1 Message Date
Felix Fietkau
461d8a6bb9 ath9k_hw: fix channel maximum power level test
The tx power applied by set_txpower is limited by the CTL (conformance
test limit) entries in the EEPROM. These can change based on the user
configured regulatory domain.
Depending on the EEPROM data this can cause the tx power to become too
limited, if the original regdomain CTLs impose lower limits than the CTLs
of the user configured regdomain.

To fix this issue, set the initial channel limits without any CTL
restrictions and only apply the CTL at run time when setting the channel
and the real tx power.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-31 10:52:25 +03:00
Felix Fietkau
1226f9e102 ath9k: fix block-ack window tracking issues
Ensure that a buffer gets tracked as part of the block-ack window as
soon as it's dequeued from the tid for the first time. Ensure that
double calls to ath_tx_addto_baw (e.g. on retransmission) don't cause
any issues.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-31 10:52:17 +03:00
Felix Fietkau
36e14a787d ath9k: report tx status on EOSP
Fixes missed indications of end of U-APSD service period to mac80211

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-31 10:52:08 +03:00
Felix Fietkau
e20c7c91ef ath9k: clear potentially stale EOSP status bit in intermediate queues
Prevents spurious ieee80211_sta_eosp calls.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-31 10:52:00 +03:00
Felix Fietkau
11f7f4f9c0 ath9k: fix moredata bit in PS buffered frame release
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-31 10:51:51 +03:00
Felix Fietkau
3a69dd3668 ath9k: don't run periodic and nf calibation at the same time
The checks already prevents periodic cal from being started while noise
floor calibration runs. It is missing checks for the other way around.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-31 10:51:43 +03:00
Felix Fietkau
a2a49e86b3 ath9k_hw: set spectral scan enable bit on trigger for AR9003+
AR9002 code and the QCA AR9003+ reference code do the same.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-31 10:51:35 +03:00
Jia-Ju Bai
bfc55fe659 ath6kl: replace GFP_ATOMIC with GFP_KERNEL in ath6kl_bmi_init()
ath6kl_bmi_init() is never called in atomic context.
It calls kzalloc() with GFP_ATOMIC, which is not necessary.
GFP_ATOMIC can be replaced with GFP_KERNEL.

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-31 10:48:45 +03:00
Sven Eckelmann
3f25911158 ath10k: prevent active scans on potential unusable channels
The QCA4019 hw1.0 firmware 10.4-3.2.1-00050 and 10.4-3.5.3-00053 (and most
likely all other) seem to ignore the WMI_CHAN_FLAG_DFS flag during the
scan. This results in transmission (probe requests) on channels which are
not "available" for transmissions.

Since the firmware is closed source and nothing can be done from our side
to fix the problem in it, the driver has to work around this problem. The
WMI_CHAN_FLAG_PASSIVE seems to be interpreted by the firmware to not
scan actively on a channel unless an AP was detected on it. Simple probe
requests will then be transmitted by the STA on the channel.

ath10k must therefore also use this flag when it queues a radar channel for
scanning. This should reduce the chance of an active scan when the channel
might be "unusable" for transmissions.

Fixes: e8a50f8ba4 ("ath10k: introduce DFS implementation")
Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-31 10:47:32 +03:00
Kalle Valo
ebfac1d0c1 ath10k: fix parenthesis alignment
These were recently introduced and found by checkpatch:

drivers/net/wireless/ath/ath10k/mac.c:6118: Alignment should match open parenthesis
drivers/net/wireless/ath/ath10k/mac.c:6121: Alignment should match open parenthesis
drivers/net/wireless/ath/ath10k/mac.c:6124: Alignment should match open parenthesis

Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-31 10:41:55 +03:00
Maharaja Kennadyrajan
db251d7df4 ath10k: add debugfs file warm_hw_reset
Debugfs support to do hardware warm reset with WMI command
WMI_PDEV_PARAM_PDEV_RESET for 10.4 and 10.2.4(if wmi
service is enabled in the firmware for backward compatibility).

This change is purely for debugging purpose when hardware hangs/mutes.

This hardware reset won't affect the connectivity but there will be small
pause in data traffic. Here we are doing BB/MAC level reset and hence
whenever the BB/MAC watchdog is triggered, it does a hardware_chip_reset.
So the target will be in the active state.

Below command used to warm reset the hardware.
echo 1 > /sys/kernel/debug/ieee80211/phyX/ath10k/warm_hw_reset

Tested in QCA988X with firmware ver 10.2.4.70.45
Tested in QCA4019 with firmware ver 10.4-3.2.1.1-00011

Signed-off-by: Maharaja Kennadyrajan <mkenna@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-30 20:59:32 +03:00
Nicholas Mc Guire
e82f57c8b9 ath10k: htt_tx: move lock into id_get function
This is only code refactoring as all call sites of
ath10k_htt_tx_alloc_msdu_id() take the same lock it can be moved into the
id_get function and the assertion dropped.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-30 20:58:44 +03:00
Colin Ian King
619c9700a8 ath6kl: remove redundant variables netlen, orig_buf, orig_len, dropped and stats
Variables netlen, orig_buf, orig_len, dropped and stats are assigned values
but are never used hence they are redundant and can be removed.

Cleans up clang warnings:
warning: variable 'netlen' set but not used [-Wunused-but-set-variable]
warning: variable 'orig_buf' set but not used [-Wunused-but-set-variable]
warning: variable 'orig_len' set but not used [-Wunused-but-set-variable]
warning: variable 'dropped' set but not used [-Wunused-but-set-variable]
warning: variable 'stats' set but not used [-Wunused-but-set-variable]

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-30 20:57:05 +03:00
Colin Ian King
e8c38062ef ath5k: remove redundant pointer rf
Pointer rf is being assigned but is never used hence it is redundant
and can be removed.

Cleans up two clang warnings:
warning: variable 'rf' set but not used [-Wunused-but-set-variable]

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-30 20:55:55 +03:00
Colin Ian King
e6712aa124 ath10k: remove redundant pointers 'dev' and 'noa'
Pointers dev and noa are being assigned but are never used hence they
are redundant and can be removed.

Cleans up clang warnings:
warning: variable 'dev' set but not used [-Wunused-but-set-variable]
warning: variable 'noa' set but not used [-Wunused-but-set-variable]

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-30 20:54:05 +03:00
Rakesh Pillai
dc405152bb ath10k: handle mgmt tx completion event
WCN3990 transmits management frames via WMI
with reference. Currently, with the management
tx completion not being handled, these frames are
not getting freed even after the transmission status
is returned by the firmware.

The transmitted management frames should be freed
when the firmware sends the over-the-air tx status of
the corresponding management frames.

Handle the wmi mgmt tx completion event and free
the corresponding management frame.

Tested HW: WCN3990
Tested FW: WLAN.HL.2.0-01188-QCAHLSWMTPLZ-1

Signed-off-by: Rakesh Pillai <pillair@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-30 20:51:47 +03:00
Surabhi Vishnoi
673bc519c5 ath10k: disable bundle mgmt tx completion event support
The tx completion of multiple mgmt frames can be bundled
in a single event and sent by the firmware to host, if this
capability is not disabled explicitly by the host. If the host
cannot handle the bundled mgmt tx completion, this capability
support needs to be disabled in the wmi init cmd, sent to the firmware.

Add the host capability indication flag in the wmi ready command,
to let firmware know the features supported by the host driver.
This field is ignored if it is not supported by firmware.

Set the host capability indication flag(i.e. host_capab) to zero,
for disabling the support of bundle mgmt tx completion. This will
indicate the firmware to send completion event for every mgmt tx
completion, instead of bundling them together and sending in a single
event.

Tested HW: WCN3990
Tested FW: WLAN.HL.2.0-01188-QCAHLSWMTPLZ-1

Signed-off-by: Surabhi Vishnoi <svishnoi@codeaurora.org>
Signed-off-by: Rakesh Pillai <pillair@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-30 20:51:38 +03:00
Pradeep Kumar Chitrapu
cd93b83ad9 ath10k: support for multicast rate control
Issues a wmi command to firmware when multicast rate change is received with the
new BSS_CHANGED_MCAST_RATE flag.  Also fixes the incorrect fixed_rate setting
for CCK rates which got introduced with addition of ath10k_rates_rev2 enum.

Tested on QCA9984 with firmware ver 10.4-3.6-00104

Signed-off-by: Pradeep Kumar Chitrapu <pradeepc@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-30 20:46:50 +03:00
Kalle Valo
1e3c43a7f1 ath10k: fix open brace location in ath10k_wmi_tlv_op_gen_dbglog_cfg()
Fixes a recently added checkpatch warning:

wmi-tlv.c:2703: open brace '{' following function definitions go on the next line

Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-07-30 20:45:22 +03:00
Kalle Valo
bf9b608e63 Merge ath-next from git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/ath.git
ath.git patches for 4.19. Major changes:

wcn36xx

* fix WEP in client mode

wil6210

* add support for Talyn-MB (Talyn ver 2.0) device

* add support for enhanced DMA firmware feature
2018-07-25 10:50:54 +03:00
Nishanth Devarajan
aea5f654e6 net/sched: add skbprio scheduler
Skbprio (SKB Priority Queue) is a queueing discipline that prioritizes packets
according to their skb->priority field. Under congestion, already-enqueued lower
priority packets will be dropped to make space available for higher priority
packets. Skbprio was conceived as a solution for denial-of-service defenses that
need to route packets with different priorities as a means to overcome DoS
attacks.

v5
*Do not reference qdisc_dev(sch)->tx_queue_len for setting limit. Instead set
default sch->limit to 64.

v4
*Drop Documentation/networking/sch_skbprio.txt doc file to move it to tc man
page for Skbprio, in iproute2.

v3
*Drop max_limit parameter in struct skbprio_sched_data and instead use
sch->limit.

*Reference qdisc_dev(sch)->tx_queue_len only once, during initialisation for
qdisc (previously being referenced every time qdisc changes).

*Move qdisc's detailed description from in-code to Documentation/networking.

*When qdisc is saturated, enqueue incoming packet first before dequeueing
lowest priority packet in queue - improves usage of call stack registers.

*Introduce and use overlimit stat to keep track of number of dropped packets.

v2
*Use skb->priority field rather than DS field. Rename queueing discipline as
SKB Priority Queue (previously Gatekeeper Priority Queue).

*Queueing discipline is made classful to expose Skbprio's internal priority
queues.

Signed-off-by: Nishanth Devarajan <ndev2021@gmail.com>
Reviewed-by: Sachin Paryani <sachin.paryani@gmail.com>
Reviewed-by: Cody Doucette <doucette@bu.edu>
Reviewed-by: Michel Machado <michel@digirati.com.br>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:44:00 -07:00
Heiner Kallweit
b8f8c8eb40 net: phy: add GBit master / slave error detection
Certain PHY's have issues when operating in GBit slave mode and can
be forced to master mode. Examples are RTL8211C, also the Micrel PHY
driver has a DT setting to force master mode.
If two such chips are link partners the autonegotiation will fail.
Standard defines a self-clearing on read, latched-high bit to
indicate this error. Check this bit to inform the user.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:41:08 -07:00
David S. Miller
7836899c34 Merge branch 'net-whitespace-cleanups'
Stephen Hemminger says:

====================
net whitespace cleanups

Ran script that I use to check for trailing whitespace and
blank lines at end of files across all files in net/ directory.
These are errors that checkpatch reports and git flags.

These are the resulting fixes broken up mostly by subsystem.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:43 -07:00
Stephen Hemminger
e446a2760f net: remove blank lines at end of file
Several files have extra line at end of file.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:43 -07:00
Stephen Hemminger
c2df560367 l2tp: remove trailing newline
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:43 -07:00
Stephen Hemminger
a17922def7 bpfilter: remove trailing newline
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
19c198d9c1 decnet: whitespace fixes
Remove trailing whitespace and extra lines at EOF

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
27782f403f x25: remove blank lines at EOF
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
9d82a1cdd3 ax25: remove blank line at EOF
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
543de8881d atm: remove blank lines at EOF
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
ed976ea730 ila: remove blank lines at EOF
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
aa46225235 sctp: whitespace fixes
Remove blank line at EOF and trailing whitespace.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
2e13b58069 xfrm: remove blank lines at EOF
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
04c6a3a40a mpls: remove trailing whitepace
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
a87e87dbf3 llc: fix whitespace issues
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
1cb1d977b4 rds: remove trailing whitespace and blank lines
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
bf9b5567da wimax: remove blank lines at EOF
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Stephen Hemminger
50f699b1f8 sched: fix trailing whitespace
Remove trailing whitespace and blank lines at EOF

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Tariq Toukan
8dd30201ce net: remove redundant input checks in SIOCSIFTXQLEN case of dev_ifsioc
The cited patch added a call to dev_change_tx_queue_len in
SIOCSIFTXQLEN case.
This obsoletes the new len comparison check done before the function call.
Remove it here.

For the desicion of keep/remove the negative value check, we examine the
range check in dev_change_tx_queue_len.
On 64-bit we will fail with -ERANGE.  The 32-bit int ifr_qlen will be sign
extended to 64-bits when it is passed into dev_change_tx_queue_len(). And
then for negative values this test triggers:

	if (new_len != (unsigned int)new_len)
		return -ERANGE;

because:
	if (0xffffffffWHATEVER != 0x00000000WHATEVER)

On 32-bit the signed value will be accepted, changing behavior.

Therefore, the negative value check is kept.

Fixes: 3f76df1982 ("net: use dev_change_tx_queue_len() for SIOCSIFTXQLEN")
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 11:36:15 -07:00
David S. Miller
c4ef85da78 Merge branch 'cxgb4-collect-free-Tx-Rx-pages-and-page-pointers'
Rahul Lakkireddy says:

====================
cxgb4: collect free Tx/Rx pages and page pointers

Patch 1 collects number of free PSTRUCT page pointers in context
memory.

Patch 2 moves the collection logic for Tx/Rx free pages to common
code, since this information needs to be collected in vmcore device
dump as well.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 10:12:22 -07:00
Rahul Lakkireddy
ae2a922fae cxgb4: move Tx/Rx free pages collection to common code
This information needs to be collected in vmcore device dump as well.
So, move to common code.

Fixes: fa145d5dfd ("cxgb4: display number of rx and tx pages free")
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 10:12:22 -07:00
Rahul Lakkireddy
9d0f180cd5 cxgb4: collect number of free PSTRUCT page pointers
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 10:12:21 -07:00
David S. Miller
6eb5e652bc Merge branch 'mlxsw-Add-extack-messages-for-tc-flower'
Ido Schimmel says:

====================
mlxsw: Add extack messages for tc flower

Nir says:

This patch set adds extack messages support to tc flower part of mlxsw.
The messages provide clear reasoning to failures, as some of the available
actions and keys are not supported in driver or HW and resources may get
exhausted.

The first patch deals with propagation of the extack pointer among the functions
dealing with key parsing and action sets handling.

Following patches 2-4 add appropriate messages across the different layers of
mlxsw tc flower implementation.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 10:10:33 -07:00
Nir Dotan
27c203cd14 mlxsw: spectrum_flower: Add extack messages
Return extack messages in order to explain failures
of unsupported actions, keys and invalid user input.

Signed-off-by: Nir Dotan <nird@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 10:10:33 -07:00
Nir Dotan
af1fe78643 mlxsw: spectrum_acl: Add extack messages
Return extack messages for failures in action set creation.
Messages provide reasons for not being able to implement
the action in HW.

Signed-off-by: Nir Dotan <nird@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 10:10:33 -07:00
Nir Dotan
9c10812afe mlxsw: core_acl_flex_actions: Add extack messages
Return extack messages for failures in action set creation.
Errors may occur when action is not currently supported or due
to lack of resources.

Signed-off-by: Nir Dotan <nird@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 10:10:33 -07:00
Nir Dotan
ad7769ca2d mlxsw: spectrum_acl: Propagate extack pointer
Propagate extack pointer in order to add extack messages for ACL.
In the follow-up patches, appropriate messages will be added
in various points.

Signed-off-by: Nir Dotan <nird@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 10:10:33 -07:00
Florian Westphal
3730cf4dd7 netlink: do not store start function in netlink_cb
->start() is called once when dump is being initialized, there is no
need to store it in netlink_cb.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 10:04:49 -07:00
David S. Miller
c93622b53e Merge tag 'mac80211-next-for-davem-2018-07-24' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
Johannes Berg says:

====================
Only a few things:
 * HE (802.11ax) support in HWSIM
 * bypass TXQ with NDP frames as they're special
 * convert ahash -> shash in lib80211 TKIP
 * avoid playing with tailroom counter defer unless
   needed to avoid issues in some cases
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 10:00:54 -07:00
Manikanta Pubbisetty
133bf90dbb mac80211: restrict delayed tailroom needed decrement
As explained in ieee80211_delayed_tailroom_dec(), during roam,
keys of the old AP will be destroyed and new keys will be
installed. Deletion of the old key causes
crypto_tx_tailroom_needed_cnt to go from 1 to 0 and the new key
installation causes a transition from 0 to 1.

Whenever crypto_tx_tailroom_needed_cnt transitions from 0 to 1,
we invoke synchronize_net(); the reason for doing this is to avoid
a race in the TX path as explained in increment_tailroom_need_count().
This synchronize_net() operation can be slow and can affect the station
roam time. To avoid this, decrementing the crypto_tx_tailroom_needed_cnt
is delayed for a while so that upon installation of new key the
transition would be from 1 to 2 instead of 0 to 1 and thereby
improving the roam time.

This is all correct for a STA iftype, but deferring the tailroom_needed
decrement for other iftypes may be unnecessary.

For example, let's consider the case of a 4-addr client connecting to
an AP for which AP_VLAN interface is also created, let the initial
value for tailroom_needed on the AP be 1.

* 4-addr client connects to the AP (AP: tailroom_needed = 1)
* AP will clear old keys, delay decrement of tailroom_needed count
* AP_VLAN is created, it takes the tailroom count from master
  (AP_VLAN: tailroom_needed = 1, AP: tailroom_needed = 1)
* Install new key for the station, assume key is plumbed in the HW,
  there won't be any change in tailroom_needed count on AP iface
* Delayed decrement of tailroom_needed count on AP
  (AP: tailroom_needed = 0, AP_VLAN: tailroom_needed = 1)

Because of the delayed decrement on AP iface, tailroom_needed count goes
out of sync between AP(master iface) and AP_VLAN(slave iface) and
there would be unnecessary tailroom created for the packets going
through AP_VLAN iface.

Also, WARN_ONs were observed while trying to bring down the AP_VLAN
interface:
(warn_slowpath_common) (warn_slowpath_null+0x18/0x20)
(warn_slowpath_null) (ieee80211_free_keys+0x114/0x1e4)
(ieee80211_free_keys) (ieee80211_del_virtual_monitor+0x51c/0x850)
(ieee80211_del_virtual_monitor) (ieee80211_stop+0x30/0x3c)
(ieee80211_stop) (__dev_close_many+0x94/0xb8)
(__dev_close_many) (dev_close_many+0x5c/0xc8)

Restricting delayed decrement to station interface alone fixes the problem
and it makes sense to do so because delayed decrement is done to improve
roam time which is applicable only for client devices.

Signed-off-by: Manikanta Pubbisetty <mpubbise@codeaurora.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2018-07-24 09:21:12 +02:00