kernel/drivers/net/wireless/ath/ath9k/debug.c, branch linux-rolling-stable

wifi: ath9k: Add RX inactivity detection and reset chip when it occurs

2024-11-19T15:32:16Z

Some ath9k chips can, seemingly at random, end up in a state which can be described as "deaf". No or nearly no interrupts are generated anymore for incoming packets. Existing links either break down after a while and new links will not be established. The circumstances leading to this "deafness" is still unclear, but some particular chips (especially 2-stream 11n SoCs, but also others) can go 'deaf' when running AP or mesh (or both) after some time. It's probably a hardware issue, and doing a channel scan to trigger a chip reset (which one normally can't do on an AP interface) recovers the hardware. The only way the driver can detect this state, is by detecting if there has been no RX activity for a while. In this case we can proactively reset the chip (which only takes a small number of milliseconds, so shouldn't interrupt things too much if it has been idle for several seconds), which functions as a workaround. OpenWrt, and various derivatives, have been carrying versions of this workaround for years, that were never upstreamed. One version[0], written by Felix Fietkau, used a simple counter and only reset if there was precisely zero RX activity for a long period of time. This had the problem that in some cases a small number of interrupts would appear even if the device was otherwise not responsive. For this reason, another version[1], written by Simon Wunderlich and Sven Eckelmann, used a time-based approach to calculate the average number of RX interrupts over a longer (four-second) interval, and reset the chip when seeing less than one interrupt per second over this period. However, that version relied on debugfs counters to keep track of the number of interrupts, which means it didn't work at all if debugfs was not enabled. This patch unifies the two versions: it uses the same approach as Felix' patch to count the number of RX handler invocations, but uses the same time-based windowing approach as Simon and Sven's patch to still handle the case where occasional interrupts appear but the device is otherwise deaf. Since this is based on ideas by all three people, but not actually directly derived from any of the patches, I'm including Suggested-by tags from Simon, Sven and Felix below, which should hopefully serve as proper credit. [0] https://patchwork.kernel.org/project/linux-wireless/patch/20170125163654.66431-3-nbd@nbd.name/ [1] https://patchwork.kernel.org/project/linux-wireless/patch/20161117083614.19188-2-sven.eckelmann@open-mesh.com/ Suggested-by: Simon Wunderlich Suggested-by: Sven Eckelmann Suggested-by: Felix Fietkau Signed-off-by: Toke Høiland-Jørgensen Tested-by: Sven Eckelmann Reviewed-by: Sven Eckelmann Tested-by: Issam Hamdi Acked-by: Simon Wunderlich Link: https://patch.msgid.link/20241106-ath9k-deaf-detection-v1-1-736a150d2425@redhat.com Signed-off-by: Jeff Johnson

move asm/unaligned.h to linux/unaligned.h

2024-10-02T21:23:23Z

asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h

wifi: ath9k: Remove error checks when creating debugfs entries

2024-08-07T08:09:11Z

We should not be checking the return values from debugfs creation at all: the debugfs functions are designed to handle errors of previously called functions and just transparently abort the creation of debugfs entries when debugfs is disabled. If we check the return value and abort driver initialisation, we break the driver if debugfs is disabled (such as when booting with debugfs=off). Earlier versions of ath9k accidentally did the right thing by checking the return value, but only for NULL, not for IS_ERR(). This was "fixed" by the two commits referenced below, breaking ath9k with debugfs=off starting from the 6.6 kernel (as reported in the Bugzilla linked below). Restore functionality by just getting rid of the return value check entirely. Link: https://bugzilla.kernel.org/show_bug.cgi?id=219122 Fixes: 1e4134610d93 ("wifi: ath9k: use IS_ERR() with debugfs_create_dir()") Fixes: 6edb4ba6fb5b ("wifi: ath9k: fix parameter check in ath9k_init_debug()") Reported-by: Daniel Tobias Tested-by: Daniel Tobias Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Kalle Valo Link: https://patch.msgid.link/20240805110225.19690-1-toke@toke.dk

wifi: ath9k: fix possible integer overflow in ath9k_get_et_stats()

2024-08-01T14:59:42Z

In 'ath9k_get_et_stats()', promote TX stats counters to 'u64' to avoid possible integer overflow. Compile tested only. Found by Linux Verification Center (linuxtesting.org) with SVACE. Signed-off-by: Dmitry Kandybka Acked-by: Toke Høiland-Jørgensen Signed-off-by: Kalle Valo Link: https://patch.msgid.link/20240725111743.14422-1-d.kandybka@gmail.com

wifi: ath9k: Remove unnecessary (void*) conversions

2023-11-29T11:28:05Z

No need cast (void *) to (struct owl_ctx *), (struct ath_hw *), (struct cmd_buf *) or other types. Signed-off-by: Wu Yunchuan Reviewed-by: Jeff Johnson Acked-by: Toke Høiland-Jørgensen Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20230919045226.524544-1-yunchuan@nfschina.com

wifi: ath9k: fix clang-specific fortify warnings

2023-09-20T13:16:53Z

When compiling with clang 16.0.6 and CONFIG_FORTIFY_SOURCE=y, I've noticed the following (somewhat confusing due to absence of an actual source code location): In file included from drivers/net/wireless/ath/ath9k/debug.c:17: In file included from ./include/linux/slab.h:16: In file included from ./include/linux/gfp.h:7: In file included from ./include/linux/mmzone.h:8: In file included from ./include/linux/spinlock.h:56: In file included from ./include/linux/preempt.h:79: In file included from ./arch/x86/include/asm/preempt.h:9: In file included from ./include/linux/thread_info.h:60: In file included from ./arch/x86/include/asm/thread_info.h:53: In file included from ./arch/x86/include/asm/cpufeature.h:5: In file included from ./arch/x86/include/asm/processor.h:23: In file included from ./arch/x86/include/asm/msr.h:11: In file included from ./arch/x86/include/asm/cpumask.h:5: In file included from ./include/linux/cpumask.h:12: In file included from ./include/linux/bitmap.h:11: In file included from ./include/linux/string.h:254: ./include/linux/fortify-string.h:592:4: warning: call to '__read_overflow2_field' declared with 'warning' attribute: detected read beyond size of field (2nd parameter); maybe use struct_group()? [-Wattribute-warning] __read_overflow2_field(q_size_field, size); In file included from drivers/net/wireless/ath/ath9k/htc_drv_debug.c:17: In file included from drivers/net/wireless/ath/ath9k/htc.h:20: In file included from ./include/linux/module.h:13: In file included from ./include/linux/stat.h:19: In file included from ./include/linux/time.h:60: In file included from ./include/linux/time32.h:13: In file included from ./include/linux/timex.h:67: In file included from ./arch/x86/include/asm/timex.h:5: In file included from ./arch/x86/include/asm/processor.h:23: In file included from ./arch/x86/include/asm/msr.h:11: In file included from ./arch/x86/include/asm/cpumask.h:5: In file included from ./include/linux/cpumask.h:12: In file included from ./include/linux/bitmap.h:11: In file included from ./include/linux/string.h:254: ./include/linux/fortify-string.h:592:4: warning: call to '__read_overflow2_field' declared with 'warning' attribute: detected read beyond size of field (2nd parameter); maybe use struct_group()? [-Wattribute-warning] __read_overflow2_field(q_size_field, size); The compiler actually complains on 'ath9k_get_et_strings()' and 'ath9k_htc_get_et_strings()' due to the same reason: fortification logic inteprets call to 'memcpy()' as an attempt to copy the whole array from it's first member and so issues an overread warning. These warnings may be silenced by passing an address of the whole array and not the first member to 'memcpy()'. Signed-off-by: Dmitry Antipov Acked-by: Toke Høiland-Jørgensen Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20230829093856.234584-1-dmantipov@yandex.ru

wifi: ath9k: consistently use kstrtoX_from_user() functions

2023-08-22T13:37:53Z

Use 'kstrtoul_from_user()' and 'kstrtobool_from_user()' where appropriate and thus avoid some code duplication. Signed-off-by: Dmitry Antipov Acked-by: Toke Høiland-Jørgensen Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20230726185046.188225-1-dmantipov@yandex.ru

wifi: ath9k: fix parameter check in ath9k_init_debug()

2023-08-22T13:36:08Z

Make IS_ERR() judge the debugfs_create_dir() function return in ath9k_init_debug() Signed-off-by: Minjie Du Acked-by: Toke Høiland-Jørgensen Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20230712114740.13226-1-duminjie@vivo.com

ath9k: add option to reset the wifi chip via debugfs

2021-10-05T14:27:31Z

Sometimes, in yet unknown cases the wifi chip stops working. To allow a watchdog in userspace to easily and quickly reset the wifi chip, add the according functionality to userspace. A reset can then be triggered via: $ echo 1 > /sys/kernel/debug/ieee80211/phy0/ath9k/reset The number of user resets can further be tracked in the row "User reset" in the same file. So far people usually used "iw scan" to fix ath9k chip hangs from userspace. Which triggers the ath9k_queue_reset(), too. The reset file however has the advantage of less overhead, which makes debugging bugs within ath9k_queue_reset() easier. Signed-off-by: Linus Lüssing Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20210914192515.9273-2-linus.luessing@c0d3.blue

ath9k: fix data bus crash when setting nf_override via debugfs

2021-02-11T06:49:45Z

When trying to set the noise floor via debugfs, a "data bus error" crash like the following can happen: [ 88.433133] Data bus error, epc == 80221c28, ra == 83314e60 [ 88.438895] Oops[#1]: [ 88.441246] CPU: 0 PID: 7263 Comm: sh Not tainted 4.14.195 #0 [ 88.447174] task: 838a1c20 task.stack: 82d5e000 [ 88.451847] $ 0 : 00000000 00000030 deadc0de 83141de4 [ 88.457248] $ 4 : b810a2c4 0000a2c4 83230fd4 00000000 [ 88.462652] $ 8 : 0000000a 00000000 00000001 00000000 [ 88.468055] $12 : 7f8ef318 00000000 00000000 77f802a0 [ 88.473457] $16 : 83230080 00000002 0000001b 83230080 [ 88.478861] $20 : 83a1c3f8 00841000 77f7adb0 ffffff92 [ 88.484263] $24 : 00000fa4 77edd860 [ 88.489665] $28 : 82d5e000 82d5fda8 00000000 83314e60 [ 88.495070] Hi : 00000000 [ 88.498044] Lo : 00000000 [ 88.501040] epc : 80221c28 ioread32+0x8/0x10 [ 88.505671] ra : 83314e60 ath9k_hw_loadnf+0x88/0x520 [ath9k_hw] [ 88.512049] Status: 1000fc03 KERNEL EXL IE [ 88.516369] Cause : 5080801c (ExcCode 07) [ 88.520508] PrId : 00019374 (MIPS 24Kc) [ 88.524556] Modules linked in: ath9k ath9k_common pppoe ppp_async l2tp_ppp cdc_mbim batman_adv ath9k_hw ath sr9700 smsc95xx sierra_net rndis_host qmi_wwan pppox ppp_generic pl2303 nf_conntrack_ipv6 mcs7830 mac80211 kalmia iptable_nat ipt_REJECT ipt_MASQUERADE huawei_cdc_ncm ftdi_sio dm9601 cfg80211 cdc_subset cdc_ncm cdc_ether cdc_eem ax88179_178a asix xt_time xt_tcpudp xt_tcpmss xt_statistic xt_state xt_nat xt_multiport xt_mark xt_mac xt_limit xt_length xt_hl xt_ecn xt_dscp xt_conntrack xt_comment xt_TCPMSS xt_REDIRECT xt_NETMAP xt_LOG xt_HL xt_FLOWOFFLOAD xt_DSCP xt_CLASSIFY usbserial usbnet usbhid slhc rtl8150 r8152 pegasus nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_flow_table_hw nf_flow_table nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack [ 88.597894] libcrc32c kaweth iptable_mangle iptable_filter ipt_ECN ipheth ip_tables hso hid_generic crc_ccitt compat cdc_wdm cdc_acm br_netfilter hid evdev input_core nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables ip6t_REJECT x_tables nf_reject_ipv6 l2tp_netlink l2tp_core udp_tunnel ip6_udp_tunnel xfrm6_mode_tunnel xfrm6_mode_transport xfrm6_mode_beet ipcomp6 xfrm6_tunnel esp6 ah6 xfrm4_tunnel xfrm4_mode_tunnel xfrm4_mode_transport xfrm4_mode_beet ipcomp esp4 ah4 tunnel6 tunnel4 tun xfrm_user xfrm_ipcomp af_key xfrm_algo sha256_generic sha1_generic jitterentropy_rng drbg md5 hmac echainiv des_generic deflate zlib_inflate zlib_deflate cbc authenc crypto_acompress ehci_platform ehci_hcd gpio_button_hotplug usbcore nls_base usb_common crc16 mii aead crypto_null cryptomgr crc32c_generic [ 88.671671] crypto_hash [ 88.674292] Process sh (pid: 7263, threadinfo=82d5e000, task=838a1c20, tls=77f81efc) [ 88.682279] Stack : 00008060 00000008 00000200 00000000 00000000 00000000 00000000 00000002 [ 88.690916] 80500000 83230080 82d5fe22 00841000 77f7adb0 00000000 00000000 83156858 [ 88.699553] 00000000 8352fa00 83ad62b0 835302a8 00000000 300a00f8 00000003 82d5fe38 [ 88.708190] 82d5fef4 00000001 77f54dc4 77f80000 77f7adb0 c79fe901 00000000 00000000 [ 88.716828] 80510000 00000002 00841000 77f54dc4 77f80000 801ce4cc 0000000b 41824292 [ 88.725465] ... [ 88.727994] Call Trace: [ 88.730532] [<80221c28>] ioread32+0x8/0x10 [ 88.734765] Code: 00000000 8c820000 0000000f <03e00008> 00000000 08088708 00000000 aca40000 03e00008 [ 88.744846] [ 88.746464] ---[ end trace db226b2de1b69b9e ]--- [ 88.753477] Kernel panic - not syncing: Fatal exception [ 88.759981] Rebooting in 3 seconds.. The "REG_READ(ah, AR_PHY_AGC_CONTROL)" in ath9k_hw_loadnf() does not like being called when the hardware is asleep, leading to this crash. The easiest way to reproduce this is trying to set nf_override while the hardware is down: $ ip link set down dev wlan0 $ echo "-85" > /sys/kernel/debug/ieee80211/phy0/ath9k/nf_override Fixing this crash by waking the hardware up before trying to set the noise floor. Similar to what other ath9k debugfs files do. Tested on a Lima board from 8devices, which has a QCA 4531 chipset. Fixes: b90189759a7f ("ath9k: add noise floor override option") Cc: Simon Wunderlich Signed-off-by: Linus Lüssing Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20210209184352.4272-1-linus.luessing@c0d3.blue