June 2021 - kernelnewbies@kernelnewbies.org - Kernelnewbies Mailing Lists

trigger timestamp
by Muni Sekhar July 8, 2021

July 8, 2021

Hi all, >From the user space test application , Is it possible to get the trigger timestamp corresponding to SNDRV_PCM_TRIGGER_START & SNDRV_PCM_TRIGGER_STOP events for audio playback capture? -- Thanks, Sekhar

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kernel build error during ubuntu linux kernel build
by ckim＠etri.re.kr July 1, 2021

July 1, 2021

Hello, all I have a strange problem in building the linux kernel from ubuntu. (I want to replace the kernel in ubuntu to debug install failure on qemu virtual machine) I downloaded ubuntu source by "git clone git://kernel.ubuntu.com/ubuntu/ubuntu-focal.git". and because I wanted to use a specific version, I did "git checkout Ubuntu-5.4.0-42.46" (this version is the one used in a ubuntu installation .iso. And you can see related askubuntu question here : https://askubuntu.com/questions/1347390/what-ubuntu-source-version-should-i- use-to-add-some-debug-prints-for-ubuntu-bo ) After git-checkout, the `git log` shows this result : commit 98c4545e2d65ed35c31056f72c4da20f6b5ea0d0 (HEAD, tag: Ubuntu-5.4.0-42.46) Author: Khalid Elmously <khalid.elmously(a)canonical.com> Date: Thu Jul 9 19:50:26 2020 -0400 UBUNTU: Ubuntu-5.4.0-42.46 Signed-off-by: Khalid Elmously <khalid.elmously(a)canonical.com> To build the kernel, I did `ARCH=arm64 CROSS_COMPILE=aarch64-none-elf- make defconfig` and `ARCH=arm64 CROSS_COMPILE=aarch64-none-elf- make -j24 Image`. But this gives me a compile error below. What can be wrong? . . CC mm/interval_tree.o CC drivers/base/regmap/regcache.o CC kernel/time/posix-cpu-timers.o CC mm/list_lru.o CC block/blk-mq.o AS arch/arm64/lib/memchr.o CC fs/ext4/migrate.o security/security.c: In function 'security_add_hooks': security/security.c:477:25: error: 'struct security_hook_heads' has no member named 'socket_getpeersec_stream' 477 | &security_hook_heads.socket_getpeersec_stream) | ^ CC kernel/time/posix-clock.o AS arch/arm64/lib/memcmp.o security/security.c: In function 'security_setprocattr': CC arch/arm64/kvm/../../../virt/kvm/arm/vgic/vgic-v2.o security/security.c:2058:27: error: 'union security_list_options' has no member named 'socket_getpeersec_stream' 2058 | socket_getpeersec_stream.socket_getpeersec_stream = NULL; | ^ In file included from ./include/linux/timer.h:5, from ./include/linux/workqueue.h:9, from ./include/linux/bpf.h:9, from security/security.c:13: security/security.c:2060:25: error: 'struct security_hook_heads' has no member named 'socket_getpeersec_stream' 2060 | &security_hook_heads.socket_getpeersec_stream, | ^ ./include/linux/list.h:857:12: note: in definition of macro 'hlist_entry_safe' 857 | ({ typeof(ptr) ____ptr = (ptr); \ | ^~~ security/security.c:2059:3: note: in expansion of macro 'hlist_for_each_entry' 2059 | hlist_for_each_entry(hp, | ^~~~~~~~~~~~~~~~~~~~ security/security.c:2060:25: error: 'struct security_hook_heads' has no member named 'socket_getpeersec_stream' 2060 | &security_hook_heads.socket_getpeersec_stream, | ^ ./include/linux/list.h:857:28: note: in definition of macro 'hlist_entry_safe' 857 | ({ typeof(ptr) ____ptr = (ptr); \ | ^~~ security/security.c:2059:3: note: in expansion of macro 'hlist_for_each_entry' 2059 | hlist_for_each_entry(hp, | ^~~~~~~~~~~~~~~~~~~~ In file included from ./include/linux/list.h:9, from ./include/linux/timer.h:5, from ./include/linux/workqueue.h:9, from ./include/linux/bpf.h:9, from security/security.c:13: ./include/linux/kernel.h:993:17: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 993 | void *__mptr = (void *)(ptr); \ | ^ ./include/linux/list.h:847:40: note: in expansion of macro 'container_of' 847 | #define hlist_entry(ptr, type, member) container_of(ptr,type,member) | ^~~~~~~~~~~~ . . BTW, when I do the same with linux-5.4.21 vanila source, it compiles ok. Can anyone give me an advice? Could this Ubuntu-5.4.0-42.46 version have a bug and maybe I need a patch? Thank you! Chan Kim

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ssh connection problem
by Er Krishna June 30, 2021

June 30, 2021

Hi everyone, Though it may not be a direct kernel problem but since I am not sure about Ssh mailing list, so asking the question here. During the iperf run on X722 card if l create multiple ssh connection from different terminal to same VM in continuous manner, l see after 10 min new ssh connection starts giving authentication issue. After adding -vvv and strace, l can see that there is problem in parsing the password and so authentication failure happens and new connection is not possible. After 10 min, automatically this problem gets resolved and and new connection can be created. Authentication problem get resolved. What could be the problem here? If anyone can help me or give some pointer about it, it will be greatly appreciated and great help for me. Thanks, Krishna

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advice on a bisect
by jim.cromie＠gmail.com June 29, 2021

June 29, 2021

I have an old 686 machine, running fedora 30 (last fedora supporting 686) processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 23 model name : Intel(R) Core(TM)2 Duo CPU E7400 @ 2.80GHz stepping : 10 microcode : 0xa0b cpu MHz : 1614.044 cache size : 3072 KB I generally keep it with a fresh kernel at least, [jimc@popeye linux]$ uname -a Linux popeye 5.13.0-rc5-j1-00030-g4c8684fe555e #210 SMP Tue Jun 15 16:56:40 MDT 2021 i686 i686 i386 GNU/Linux recently, I found it wouldnt boot, so bisected. [jimc@popeye linux]$ git bisect log git bisect start # bad: [009c9aa5be652675a06d5211e1640e02bbb1c33d] Linux 5.13-rc6 git bisect bad 009c9aa5be652675a06d5211e1640e02bbb1c33d # good: [8124c8a6b35386f73523d27eacb71b5364a68c4c] Linux 5.13-rc4 git bisect good 8124c8a6b35386f73523d27eacb71b5364a68c4c # good: [bd7b12aa6081c3755b693755d608f58e13798a60] Merge tag 'powerpc-5.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux git bisect good bd7b12aa6081c3755b693755d608f58e13798a60 # bad: [fd2cd569a43635877771c00b8a2f4f26275e5562] Merge tag 'sound-5.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound git bisect bad fd2cd569a43635877771c00b8a2f4f26275e5562 # good: [9b1111fa80df22c8cb6f9f8634693812cb958f4f] Merge tag 'regulator-fix-v5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator git bisect good 9b1111fa80df22c8cb6f9f8634693812cb958f4f # bad: [cd1245d75ce93b8fd206f4b34eb58bcfe156d5e9] Merge tag 'platform-drivers-x86-v5.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86 git bisect bad cd1245d75ce93b8fd206f4b34eb58bcfe156d5e9 # bad: [2f673816b2db30ce6122fe0e5e6a00de20e8d99a] Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm git bisect bad 2f673816b2db30ce6122fe0e5e6a00de20e8d99a # bad: [368094df48e680fa51cedb68537408cfa64b788e] Merge tag 'for-linus-5.13b-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip git bisect bad 368094df48e680fa51cedb68537408cfa64b788e # good: [4c8684fe555e95100030bd330d0a2780ac27952e] Merge tag 'spi-fix-v5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi git bisect good 4c8684fe555e95100030bd330d0a2780ac27952e # good: [d4c6399900364facd84c9e35ce1540b6046c345f] vmlinux.lds.h: Avoid orphan section with !SMP git bisect good d4c6399900364facd84c9e35ce1540b6046c345f # good: [374aeb91db48bb52216bb9308d611c816fb6cacb] Merge tag 'orphans-v5.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux git bisect good 374aeb91db48bb52216bb9308d611c816fb6cacb # good: [107866a8eb0b664675a260f1ba0655010fac1e08] xen-netback: take a reference to the RX task thread git bisect good 107866a8eb0b664675a260f1ba0655010fac1e08 # first bad commit: [368094df48e680fa51cedb68537408cfa64b788e] Merge tag 'for-linus-5.13b-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip [jimc@popeye linux]$ after bisecting (long time, not much effort) I booted the "bad" kernel to single user (added 'S' to end of bootline - is this universal ?) and poked around, so failure is more subtle than total. by casual observation, boot hangs at dbus startup the bad-booting kernel does manage to log its progress, journalct -b-1 shows : Jun 17 03:06:11 popeye kernel: Run /init as init process Jun 17 03:06:11 popeye kernel: with arguments: Jun 17 03:06:11 popeye kernel: /init Jun 17 03:06:11 popeye kernel: rhgb Jun 17 03:06:11 popeye kernel: 2 Jun 17 03:06:11 popeye kernel: with environment: Jun 17 03:06:11 popeye kernel: HOME=/ Jun 17 03:06:11 popeye kernel: TERM=linux Jun 17 03:06:11 popeye kernel: BOOT_IMAGE=/vmlinuz-5.13.0-rc6-cln Jun 17 03:06:14 popeye systemd[1]: Started Plymouth switch root service. Jun 17 03:06:14 popeye audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=kernel msg='unit=plymouth-switch> Jun 17 03:06:14 popeye audit[1]: SERVICE_STOP pid=1 uid=0 auid=4294967295 ses=4294967295 subj=kernel msg='unit=plymouth-switch-> Jun 17 03:06:14 popeye systemd[1]: Starting Switch Root... Jun 17 03:06:14 popeye systemd[1]: Switching root. Jun 17 03:06:14 popeye systemd-journald[131]: Journal stopped Jun 17 09:06:22 popeye systemd-journald[131]: Received SIGTERM from PID 1 (systemd). Jun 17 09:06:22 popeye kernel: printk: systemd: 18 output lines suppressed due to ratelimiting Jun 17 09:06:22 popeye kernel: kauditd_printk_skb: 21 callbacks suppressed Jun 17 09:06:22 popeye kernel: audit: type=1404 audit(1623920776.499:32): enforcing=1 old_enforcing=0 auid=4294967295 ses=42949> Jun 17 09:06:22 popeye kernel: SELinux: Permission watch in class filesystem not defined in policy. Jun 17 09:06:22 popeye kernel: SELinux: Permission watch in class file not defined in policy. (at end) Jun 17 09:06:33 popeye systemd-logind[617]: Watching system buttons on /dev/input/event0 (Power Button) Jun 17 09:06:33 popeye systemd-logind[617]: Watching system buttons on /dev/input/event2 (USB USB Keykoard) Jun 17 09:06:33 popeye systemd-logind[617]: Watching system buttons on /dev/input/event3 (USB USB Keykoard Consumer Control) Jun 17 09:06:33 popeye systemd-logind[617]: Watching system buttons on /dev/input/event4 (USB USB Keykoard System Control) Jun 17 09:06:33 popeye rsyslogd[604]: [origin software="rsyslogd" swVersion="8.2002.0" x-pid="604" x-info="https://www.rsyslog.> Jun 17 09:06:33 popeye systemd[1]: Started System Logging Service. Jun 17 09:06:33 popeye audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg=> Jun 17 09:06:33 popeye ModemManager[605]: <info> ModemManager (version 1.10.2-1.fc30) starting in system bus... Jun 17 09:06:33 popeye rsyslogd[604]: imjournal: fscanf on state file `/var/lib/rsyslog/imjournal.state' failed [v8.2002.0 try> Jun 17 09:06:33 popeye rsyslogd[604]: imjournal: ignoring invalid state file /var/lib/rsyslog/imjournal.state [v8.2002.0] Jun 17 09:06:33 popeye chronyd[625]: Frequency -3.051 +/- 0.183 ppm read from /var/lib/chrony/drift Jun 17 09:06:33 popeye chronyd[625]: Using right/UTC timezone to obtain leap second data Jun 17 09:06:34 popeye systemd[1]: Started NTP client/server. Jun 17 09:06:34 popeye audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg=> Jun 17 09:06:34 popeye smartd[612]: smartd 7.1 2019-12-30 r5022 [i686-linux-5.13.0-rc6-cln] (local build) Jun 17 09:06:34 popeye smartd[612]: Copyright (C) 2002-19, Bruce Allen, Christian Franke, www.smartmontools.org Jun 17 09:06:34 popeye smartd[612]: Opened configuration file /etc/smartmontools/smartd.conf Jun 17 09:06:34 popeye smartd[612]: Configuration file /etc/smartmontools/smartd.conf was parsed, found DEVICESCAN, scanning de> Jun 17 09:06:34 popeye smartd[612]: Device: /dev/sda, type changed from 'scsi' to 'sat' Jun 17 09:06:34 popeye smartd[612]: Device: /dev/sda [SAT], opened Jun 17 09:06:34 popeye smartd[612]: Device: /dev/sda [SAT], ST3160318AS, S/N:9VY1J685, WWN:5-000c50-0159dbd9f, FW:CC44, 160 GB Jun 17 09:06:34 popeye smartd[612]: Device: /dev/sda [SAT], found in smartd database: Seagate Barracuda 7200.12 Jun 17 09:06:34 popeye smartd[612]: Device: /dev/sda [SAT], WARNING: A firmware update for this drive may be available, Jun 17 09:06:34 popeye smartd[612]: see the following Seagate web pages: Jun 17 09:06:34 popeye smartd[612]: http://knowledge.seagate.com/articles/en_US/FAQ/207931en Jun 17 09:06:34 popeye smartd[612]: http://knowledge.seagate.com/articles/en_US/FAQ/213891en Jun 17 09:06:34 popeye smartd[612]: Device: /dev/sda [SAT], is SMART capable. Adding to "monitor" list. Jun 17 09:06:34 popeye smartd[612]: Monitoring 1 ATA/SATA, 0 SCSI/SAS and 0 NVMe devices Jun 17 09:06:35 popeye systemd[1]: Started Self Monitoring and Reporting Technology (SMART) Daemon. Jun 17 09:06:35 popeye audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg=> Jun 17 09:06:36 popeye systemd[1]: Started D-Bus System Message Bus. Jun 17 09:06:36 popeye audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 msg=> Jun 17 09:06:36 popeye dbus-broker-launch[623]: ERROR proc_get_seclabel @ ../src/util/proc.c +31: Permission denied Jun 17 09:06:36 popeye dbus-broker-launch[623]: broker_new @ ../src/broker/broker.c +105 Jun 17 09:06:36 popeye dbus-broker-launch[623]: run @ ../src/broker/main.c +244 Jun 17 09:06:36 popeye dbus-broker-launch[623]: main @ ../src/broker/main.c +270 Jun 17 09:06:36 popeye dbus-broker-launch[623]: ERROR service_add @ ../src/launch/service.c +545: Connection reset by peer Jun 17 09:06:36 popeye dbus-broker-launch[623]: launcher_add_services @ ../src/launch/launcher.c +809 Jun 17 09:06:36 popeye dbus-broker-launch[623]: launcher_run @ ../src/launch/launcher.c +1385 Jun 17 09:06:36 popeye dbus-broker-launch[623]: run @ ../src/launch/main.c +153 Jun 17 09:06:36 popeye dbus-broker-launch[623]: main @ ../src/launch/main.c +181 Jun 17 09:06:36 popeye dbus-broker-launch[623]: Exiting due to fatal error: -104 Jun 17 09:06:42 popeye rsyslogd[604]: imjournal from <popeye:dhclient>: begin to drop messages due to rate-limiting lines 1430-1473/1473 (END) at this point, things hung & I powercycled to reboot. I cant quite explain the logging around 9:06, it looks more orderly than the powercycle I recall. Im gonna have to repeat this test, noting times etc. separately Ive been wanting to find another distro which supports 686 and older hardware, thats now arriving sooner, since box doesnt well serve its most common use. any good distro reqs ?

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Kernel Compile Issue
by Aruna Hewapathirane June 29, 2021

June 29, 2021

Hello everyone, I am trying to compile a old kernel and it compiles fine. I used: time make -j$(nproc) and this is a-ok and works. make modules_install works fine. Now when I try to install the newly compiled kernel I get this error below. Error! Bad return status for module build on kernel: 3.18.2-testing (x86_64) it says Consult /var/lib/dkms/open-vm-tools/9.4.6/build/make.log for more information. and this file shows me what is below: ============================================================== DKMS make.log for open-vm-tools-9.4.6 for kernel 3.18.2-testing (x86_64) Tue Jun 22 22:30:14 EDT 2021 /bin/sh: 1: test: -I./arch/x86/include: unexpected operator Using standalone build system. Makefile:167: Makefile.normal: No such file or directory make[2]: *** No rule to make target 'Makefile.normal'. Stop. /bin/sh: 1: test: -I./arch/x86/include: unexpected operator Using standalone build system. Makefile:167: Makefile.normal: No such file or directory make[2]: *** No rule to make target 'Makefile.normal'. Stop. =============================================================== I can use all the help I can get right now. Anyone ever experience this ? If so is is there a fix or workaround ? What causes this error ? I have multiple kernels on this ancient box and would really prefer not to have to wipe everything and reinstall from scratch. The only thing I did recently was install Virtualbox and Wireshark. Both work no issues. If anyone has any pointers would be most welcome and much appreciated. Thanks - Aruna

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Query: UBIFS: How to detect empty volumes
by Pintu Agarwal June 27, 2021

June 27, 2021

Hi, I have one basic query related to UBIFS volumes on a system with NAND partition. In short, how to detect a particular empty volume inside a system partition while flashing the partition image? Suppose I have one big system partition that consists of 4-5 ubi volumes inside it with varying sizes. Lets say: -- System Partition (ubi image) - rootfs volume (ro, squashfs) - data volume (rw, ubifs) - firmware volume (ro, ubifs) - some-other volume (ro, squashfs) Consider that all these could be flashed together as part of system.ubi image in a single shot from the bootloader. Now, suppose, one of the volume image (say firmware) is missing or remains empty (as you know we can have empty volumes). So, during system image flashing, we wanted to detect if one of the volume (firmware) is empty. Since this is an important volume, so we wanted to detect if this volume is empty/missing we will abort flashing the system partition. As there is no point in booting the system without this partition. So, I am exploring options, how can this be detected ? I mean is there any kind of magic number or header information which we can read to detect a particular empty volume ? Can we get any information from just "system.ubi" image to indicate about the volume information ? Also it could be possible that 2 or more volumes are empty, but we are only concerned about one particular volume (firmware), so how to detect particular volume ? If anyone has any thoughts about this requirement, please share your opinion. Thanks, Pintu

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Wikibook Linux kernel
by Constantine Shulyupin June 25, 2021

June 25, 2021

Dear Linux kernel documentation writers and readers: Writing Linux documentation is a huge complex collaborative process. To make it better I invite you to contribute to https://en.wikibooks.org/wiki/The_Linux_Kernel . Main benefits of the book: - Readers friendly architecture - Matrix table of contents - Convenient common wikimedia format - Hosted on wikibooks.org - Updateable by everyone. I've designed the front page matrix table of contents and composed draft articles with outline, links to kernel documentation, sources and other resources. Sometimes visitors of the book contribute to it. My vision is to have a complete updated wikibook about Linux kernel written by many experienced developers. Please vist page https://en.wikibooks.org/wiki/The_Linux_Kernel/About for the book desripton. Welcome to contribute to https://en.wikibooks.org/wiki/The_Linux_Kernel! Sincerely yours Constantine Shulyupin -- Constantine Shulyupin

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Adding a custom layer 3 protocol driver
by Cedric Velandres June 25, 2021

June 25, 2021

Hi everyone, We're currently developing a new communication using custom layer 2 and 3 that we'll be using in a cubesat and I'm looking on how to create the layer 3 driver for linux (similar to af_inet.c but the headers are completely different). I've read something similar in a thread about a previously asked question here, but it didn't really answer my questions. And so, my questions are: 1. Will it suffice to patch linux/socket.h and insert the PF_xxxx before PF_MAX then use the added PF_xxxx as family in struct net_proto_family? 2. Is there another way to do the above without patching and only in an out-of-tree module? 3. How do I expose the new AF_xxxx to userspace? It seems like macros for AF_xxxx are placed in bits/socket.h, but I haven't found a way to patch it. Thanks, Cedric

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why does an in-tree loadable module taint the kernel
by jim.cromie＠gmail.com June 16, 2021

June 16, 2021

serio_raw is apparently tainting the kernel when its modprobed. why ? other modules load properly, no code changes to this module bash-5.1# dmesg | grep -i taint [ 6.517150] serio_raw: module verification failed: signature and/or required key missing - tainting kernel [ 7.449072] CPU: 0 PID: 203 Comm: systemd-udevd Tainted: G E 5.13.0-rc6-lm1-00004-g28dc6f490a7f #106

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USB sound card issues
by Muni Sekhar June 15, 2021

June 15, 2021

Hi all, I am using a USB sound card(snd-usb-audio), and it fails while doing the audio recording "arecord: pcm_read:2032: read error: Input/output error". What could be the problem? and is there a workaround for this? $ arecord -l **** List of CAPTURE Hardware Devices **** card 1: BT_AG [BT_002], device 0: USB Audio [USB Audio] Subdevices: 1/1 Subdevice #0: subdevice #0 $ arecord --device hw:1,0 --channels 1 --format S16_LE --rate 32000_Hz x.wav Recording WAVE 'x.wav' : Signed 16 bit Little Endian, Rate 32000 Hz, Mono arecord: pcm_read:2032: read error: Input/output error -- Thanks, Sekhar

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