spectral scan control interface is exposed through debugfs eentry.
Relayfs is used to collect the spectral data. These interfaces are
similar to ath10k spectral.
spectral debugfs interfaces are below,
echo background > /sys/kernel/debug/ieee80211/phy0/ath11k/spectral_scan_ctl
echo trigger > /sys/kernel/debug/ieee80211/phy0/ath11k/spectral_scan_ctl
iw dev wlan0 scan
echo disable > /sys/kernel/debug/ieee80211/phy0/ath11k/spectral_scan_ctl
cat /sys/kernel/debug/ieee80211/phy0/ath11k/spectral_scan0 > fft_samples.dump
Tested-on: IPQ8074 WLAN.HK.2.1.0.1-01228-QCAHKSWPL_SILICONZ-1
Signed-off-by: Karthikeyan Periyasamy <periyasa@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1591688014-26441-2-git-send-email-periyasa@codeaurora.org
Add direct buffer ring (dbring) with helper API, which is used by the
spectral scan. Initialise the direct buffer ring based on the dma ring
capability, which get announced in the wmi service ready extended event.
This ring is slightly changed from data path rings. Compare to data path
ring this ring shares the hp and tp address to firmware though WMI commands.
Also the replenish buffer size is derived from firmware announcement.
driver receive indication through WMI event
WMI_PDEV_DMA_RING_BUF_RELEASE_EVENTID.
Tested-on: IPQ8074 WLAN.HK.2.1.0.1-01228-QCAHKSWPL_SILICONZ-1
Signed-off-by: Karthikeyan Periyasamy <periyasa@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1591688014-26441-1-git-send-email-periyasa@codeaurora.org
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.
This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.
There are a variety of indentation styles found.
a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'
In order to convert all of them to 1 tab + 'help', I ran the
following commend:
$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This adds support required for configuring min_data_rate of 6GHz oper IE
and peer_he_caps_6ghz in peer assoc command. The Minimum Rate field
indicates the minimum rate, in units of 1 Mb/s, that the non-AP STA is
allowed to use for sending PPDUs as defined in IEEE P802.11ax™/D6.0.
Signed-off-by: Pradeep Kumar Chitrapu <pradeepc@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200603001724.12161-5-pradeepc@codeaurora.org
Pull networking updates from David Miller:
1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
Augusto von Dentz.
2) Add GSO partial support to igc, from Sasha Neftin.
3) Several cleanups and improvements to r8169 from Heiner Kallweit.
4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
device self-test. From Andrew Lunn.
5) Start moving away from custom driver versions, use the globally
defined kernel version instead, from Leon Romanovsky.
6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.
7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.
8) Add sriov and vf support to hinic, from Luo bin.
9) Support Media Redundancy Protocol (MRP) in the bridging code, from
Horatiu Vultur.
10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.
11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
Dubroca. Also add ipv6 support for espintcp.
12) Lots of ReST conversions of the networking documentation, from Mauro
Carvalho Chehab.
13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
from Doug Berger.
14) Allow to dump cgroup id and filter by it in inet_diag code, from
Dmitry Yakunin.
15) Add infrastructure to export netlink attribute policies to
userspace, from Johannes Berg.
16) Several optimizations to sch_fq scheduler, from Eric Dumazet.
17) Fallback to the default qdisc if qdisc init fails because otherwise
a packet scheduler init failure will make a device inoperative. From
Jesper Dangaard Brouer.
18) Several RISCV bpf jit optimizations, from Luke Nelson.
19) Correct the return type of the ->ndo_start_xmit() method in several
drivers, it's netdev_tx_t but many drivers were using
'int'. From Yunjian Wang.
20) Add an ethtool interface for PHY master/slave config, from Oleksij
Rempel.
21) Add BPF iterators, from Yonghang Song.
22) Add cable test infrastructure, including ethool interfaces, from
Andrew Lunn. Marvell PHY driver is the first to support this
facility.
23) Remove zero-length arrays all over, from Gustavo A. R. Silva.
24) Calculate and maintain an explicit frame size in XDP, from Jesper
Dangaard Brouer.
25) Add CAP_BPF, from Alexei Starovoitov.
26) Support terse dumps in the packet scheduler, from Vlad Buslov.
27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.
28) Add devm_register_netdev(), from Bartosz Golaszewski.
29) Minimize qdisc resets, from Cong Wang.
30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
eliminate set_fs/get_fs calls. From Christoph Hellwig.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
selftests: net: ip_defrag: ignore EPERM
net_failover: fixed rollback in net_failover_open()
Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
vmxnet3: allow rx flow hash ops only when rss is enabled
hinic: add set_channels ethtool_ops support
selftests/bpf: Add a default $(CXX) value
tools/bpf: Don't use $(COMPILE.c)
bpf, selftests: Use bpf_probe_read_kernel
s390/bpf: Use bcr 0,%0 as tail call nop filler
s390/bpf: Maintain 8-byte stack alignment
selftests/bpf: Fix verifier test
selftests/bpf: Fix sample_cnt shared between two threads
bpf, selftests: Adapt cls_redirect to call csum_level helper
bpf: Add csum_level helper for fixing up csum levels
bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
crypto/chtls: IPv6 support for inline TLS
Crypto/chcr: Fixes a coccinile check error
Crypto/chcr: Fixes compilations warnings
...
Advertise support for multicast frame registration and update the RX
filter based on the recently added FIF_MCAST_ACTION to allow broadcast
Action frames to be received. This is needed for Device Provisioning
Protocol (DPP) use cases that use broadcast Public Action frames.
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200426084733.7889-2-jouni@codeaurora.org
Advertise support for multicast frame registration and update the RX
filter based on the recently added FIF_MCAST_ACTION to allow broadcast
Action frames to be received. This is needed for Device Provisioning
Protocol (DPP) use cases that use broadcast Public Action frames.
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200426084733.7889-1-jouni@codeaurora.org
Johannes Berg says:
====================
One batch of changes, containing:
* hwsim improvements from Jouni and myself, to be able to
test more scenarios easily
* some more HE (802.11ax) support
* some initial S1G (sub 1 GHz) work for fractional MHz channels
* some (action) frame registration updates to help DPP support
* along with other various improvements/fixes
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
If 'thermal_cooling_device_register()' fails, we must undo what has been
allocated so far. So we must go to 'err_thermal_destroy' instead of
returning directly
In case of error in 'ath11k_thermal_register()', the previous
'thermal_cooling_device_register()' call must also be undone. Move the
'ar->thermal.cdev = cdev' a few lines above in order for this to be done
in 'ath11k_thermal_unregister()' which is called in the error handling
path.
Fixes: 2a63bbca06 ("ath11k: add thermal cooling device support")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200513201454.258111-1-christophe.jaillet@wanadoo.fr
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200507151758.GA4962@embeddedor
HTT EXT stats comes in stream of TLVs spanning over multiple
messages. Currently completion is being sent for each message
which is creating a race where stats_req is being accessed
for filling in second message after the memory is already
freed in release operation. Fix this by issuing completion
once all the messages are received and processed. Driver
knows this info from DONE bit set in htt msg.
Also fix locking required for htt stats.
Co-developed-by: Miles Hu <milehu@codeaurora.org>
Signed-off-by: Miles Hu <milehu@codeaurora.org>
Signed-off-by: Pradeep Kumar Chitrapu <pradeepc@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1589221074-28778-1-git-send-email-pradeepc@codeaurora.org
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200507151120.GA4469@embeddedor
gcc-10 correctly points out a bug with a zero-length array in
struct ath10k_pci:
drivers/net/wireless/ath/ath10k/ahb.c: In function 'ath10k_ahb_remove':
drivers/net/wireless/ath/ath10k/ahb.c:30:9: error: array subscript 0 is outside the bounds of an interior zero-length array 'struct ath10k_ahb[0]' [-Werror=zero-length-bounds]
30 | return &((struct ath10k_pci *)ar->drv_priv)->ahb[0];
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/net/wireless/ath/ath10k/ahb.c:13:
drivers/net/wireless/ath/ath10k/pci.h:185:20: note: while referencing 'ahb'
185 | struct ath10k_ahb ahb[0];
| ^~~
The last addition to the struct ignored the comments and added
new members behind the array that must remain last.
Change it to a flexible-array member and move it last again to
make it work correctly, prevent the same thing from happening
again (all compilers warn about flexible-array members in the
middle of a struct) and get it to build without warnings.
Fixes: 521fc37be3 ("ath10k: Avoid override CE5 configuration for QCA99X0 chipsets")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200509120707.188595-2-arnd@arndb.de
gcc-10 started warning about out-of-bounds access for zero-length
arrays:
In file included from drivers/net/wireless/ath/ath10k/core.h:18,
from drivers/net/wireless/ath/ath10k/htt_rx.c:8:
drivers/net/wireless/ath/ath10k/htt_rx.c: In function 'ath10k_htt_rx_tx_fetch_ind':
drivers/net/wireless/ath/ath10k/htt.h:1683:17: warning: array subscript 65535 is outside the bounds of an interior zero-length array 'struct htt_tx_fetch_record[0]' [-Wzero-length-bounds]
1683 | return (void *)&ind->records[le16_to_cpu(ind->num_records)];
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/wireless/ath/ath10k/htt.h:1676:29: note: while referencing 'records'
1676 | struct htt_tx_fetch_record records[0];
| ^~~~~~~
Make records[] a flexible array member to allow this, moving it behind
the other zero-length member that is not accessed in a way that gcc
warns about.
Fixes: 22e6b3bc5d ("ath10k: add new htt definitions")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200509120707.188595-1-arnd@arndb.de
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200507151921.GA5083@embeddedor
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200507041127.GA31587@embeddedor
Sparse warned:
drivers/net/wireless/ath/ath10k/wmi-tlv.c:3013:34: warning: incorrect
type in assignment (different base types)
drivers/net/wireless/ath/ath10k/wmi-tlv.c:3013:34: expected
restricted __le32 [usertype] reset_after_request
drivers/net/wireless/ath/ath10k/wmi-tlv.c:3013:34: got unsigned int
[usertype] reset
Tested with QCA6174 SDIO with firmware WLAN.RMH.4.4.1-00042.
Fixes: 0f7cb26830 ("ath10k: add rx bitrate report for SDIO")
Signed-off-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1588747649-18051-1-git-send-email-kvalo@codeaurora.org
gcc-10 warns about accesses inside of a zero-length array:
drivers/net/wireless/ath/wil6210/cfg80211.c: In function 'wil_cfg80211_scan':
drivers/net/wireless/ath/wil6210/cfg80211.c:970:23: error: array subscript 255 is outside the bounds of an interior zero-length array 'struct <anonymous>[0]' [-Werror=zero-length-bounds]
970 | cmd.cmd.channel_list[cmd.cmd.num_channels++].channel = ch - 1;
| ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/net/wireless/ath/wil6210/wil6210.h:17,
from drivers/net/wireless/ath/wil6210/cfg80211.c:11:
drivers/net/wireless/ath/wil6210/wmi.h:477:4: note: while referencing 'channel_list'
477 | } channel_list[0];
| ^~~~~~~~~~~~
Turn this into a flexible array to avoid the warning.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200505143332.1398524-1-arnd@arndb.de
Currently when the sending of any management pkt
via wmi command fails, the packet is being unmapped
freed in the error handling. But the idr entry added,
which is used to track these packet is not getting removed.
Hence, during unload, in wmi cleanup, all the entries
in IDR are removed and the corresponding buffer is
attempted to be freed. This can cause a situation where
one packet is attempted to be freed twice.
Fix this error by rmeoving the msdu from the idr
list when the sending of a management packet over
wmi fails.
Tested HW: WCN3990
Tested FW: WLAN.HL.3.1-01040-QCAHLSWMTPLZ-1
Fixes: 1807da4973 ("ath10k: wmi: add management tx by reference support over wmi")
Signed-off-by: Rakesh Pillai <pillair@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1588667015-25490-1-git-send-email-pillair@codeaurora.org
The qmi infrastructure sends the client a del_server
event when the client releases its qmi handle. This
is not the msg indicating the actual qmi server exiting.
In such cases the del_server msg should not be processed,
since the wifi firmware does not reset its qmi state.
Hence skip the processing of del_server event when the
driver is unloading.
Tested HW: WCN3990
Tested FW: WLAN.HL.3.1-01040-QCAHLSWMTPLZ-1
Fixes: ba94c753cc ("ath10k: add QMI message handshake for wcn3990 client")
Signed-off-by: Rakesh Pillai <pillair@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1588663061-12138-1-git-send-email-pillair@codeaurora.org
Kalle Valo says:
====================
wireless-drivers-next patches for v5.8
First set of patches for v5.8. Changes all over, ath10k apparently
seeing most new features this time. rtw88 also had lots of changes due
to preparation for new hardware support.
In this pull request there's also a new macro to include/linux/iopoll:
read_poll_timeout_atomic(). This is needed by rtw88 for atomic
polling.
Major changes:
ath11k
* add debugfs file for testing ADDBA and DELBA
* add 802.11 encapsulation offload on hardware support
* add htt_peer_stats_reset debugfs file
ath10k
* enable VHT160 and VHT80+80 modes
* enable radar detection in secondary segment
* sdio: disable TX complete indication to improve throughput
* sdio: decrease power consumption
* sdio: add HTT TX bundle support to increase throughput
* sdio: add rx bitrate reporting
ath9k
* improvements to AR9002 calibration logic
carl9170
* remove buggy P2P_GO support
p54usb
* add support for AirVasT USB stick
rtw88
* add support for antenna configuration
ti wlcore
* add support for AES_CMAC cipher
iwlwifi
* support for a few new FW API versions
* new hw configs
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200504201224.GA32282@embeddedor
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200504200838.GA31974@embeddedor
