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

Kernel 4.14: Using dm-verity with squashfs rootfs - mounting issue
by Pintu Agarwal July 20, 2021

July 20, 2021

Hi, Our ARM32 Linux embedded system consists of these: * Linux Kernel: 4.14 * Processor: Qualcomm Arm32 Cortex-A7 * Storage: NAND 512MB * Platform: Simple busybox * Filesystem: UBIFS, Squashfs * Consists of nand raw partitions, squashfs ubi volumes. My requirement: We wanted to use dm-verity at boot time to check the integrity of squashfs-rootfs before mounting. Problem: dm-0 is not able to locate and mount the squash fs rootfs block. The same approach is working when emulating with ext4 but fails with squashfs. Logs: [....] [ 0.000000] Kernel command line: [...] verity="96160 12020 d7b8a7d0c01b9aec888930841313a81603a50a2a7be44631c4c813197a50d681 0 " rootfstype=squashfs root=/dev/mtdblock34 ubi.mtd=30,0,30 [...] root=/dev/dm-0 dm="system none ro,0 96160 verity 1 /dev/mtdblock34 /dev/mtdblock39 4096 4096 12020 8 sha256 d7b8a7d0c01b9aec888930841313a81603a50a2a7be44631c4c813197a50d681 aee087a5be3b982978c923f566a94613496b417f2af592639bc80d141e34dfe7" [....] [ 4.693620] vreg_conn_pa: disa▒[ 4.700662] md: Skipping autodetection of RAID arrays. (raid=autodetect will force) [ 4.700713] device-mapper: init: attempting early device configuration. [ 4.708224] device-mapper: init: adding target '0 96160 verity 1 /dev/mtdblock34 /dev/mtdblock39 4096 4096 12020 8 sha256 d7b8a7d0c01b9aec888930841313a81603a50a2a7be44631c4c813197a50d681 aee087a5be3b982978c923f566a94613496b417f2af592639bc80d141e34dfe7' [ 4.714979] device-mapper: verity: sha256 using implementation "sha256-generic" [ 4.737808] device-mapper: init: dm-0 is ready [....] [ 5.278103] No filesystem could mount root, tried: [ 5.278107] squashfs [ 5.280477] [ 5.287627] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(253,0) [...] Not sure, why is it still locating block "253" here which seems like a MAJOR number ? Working logs on ext4: [....] [ 4.529822] v▒[ 4.534035] md: Skipping autodetection of RAID arrays. (raid=autodetect will force) [ 4.534087] device-mapper: init: attempting early device configuration. [ 4.550316] device-mapper: init: adding target '0 384440 verity 1 /dev/ubiblock0_0 /dev/ubiblock0_0 4096 4096 48055 48063 sha256 a02e0c13afb31e99b999c64aae6f4644c24addbc58db5689902cc5ba0be2d15b aee087a5be3b982978c923f566a94613496b417f2af592639bc80d141e34dfe7 10 restart_on_corruption ignore_zero_blocks use_fec_from_device /dev/ubiblock0_0 fec_roots 2 fec_blocks 48443 fec_start 48443' [ 4.572215] device-mapper: verity: sha256 using implementation "sha256-generic" [ 4.610692] device-mapper: init: dm-0 is ready [ 4.720174] EXT4-fs (dm-0): mounted filesystem with ordered data mode. Opts: (null) [ 4.720438] VFS: Mounted root (ext4 filesystem) readonly on device 253:0. [ 4.737256] devtmpfs: mounted [....] Questions: a) Is dm-verity supposed to work on squashfs block devices ? b) Are there any known issues with dm-verity on Kernel 4.14 ? c) Are there any patches that we are missing ? Thanks, Pintu

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How to comment or reply to others?
by abdalrhman masalkhi July 19, 2021

July 19, 2021

Hello everyone, I am having some trouble replying to other comments, I have submitted some patches and then I have received some comments from reviews, I tried to reply to them by just prefixing the subject line Re: instead of replying, I have posted a new thread.. I looked into the FAQ, I have not find the answer, I have google it, and I have not find any answer.. could someone please direct me to the correct article which talking about replying and comment in the lkml, or give me some tips! I would appreciate it. Kind regards, Abdalrhman Masalkhi

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Not getting serial console prints
by Ramanagouda Patil July 16, 2021

July 16, 2021

Hello Greeting!! Sorry this could be a silly question, as i am new to this. Trying to port linux kernel to my new rcar arm 64bit soc board. I got binaries to start with after flashing them don't see any serial output. How do I configure my serial console in kernel? Thanks Ramana

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Intel i40e driver call centos 4.14.44 kernel crash!
by Oracle July 13, 2021

July 13, 2021

 With centos kernel 4.14.44! Jul 12 00:49:25 cdm-storage kernel: ---[ end trace 81d5684fa78a43bb ]--- Jul 12 00:49:25 cdm-storage kernel: i40e 0000:1a:00.1 eth1: tx_timeout: VSI_seid: 397, Q 34, NTC: 0x5e, HWB: 0x71, NTU: 0x71, TAIL: 0x71, INT: 0x0 Jul 12 00:49:25 cdm-storage kernel: i40e 0000:1a:00.1 eth1: tx_timeout recovery level 1, hung_queue 34 Jul 12 00:49:25 cdm-storage kernel: bond0: link status definitely down for interface eth1, disabling it Jul 12 00:49:25 cdm-storage kernel: i40e 0000:1a:00.1: DCBX offload is not supported or is disabled for this PF. Jul 12 00:49:25 cdm-storage kernel: i40iw_deinit_device: state = 11 Jul 12 00:49:25 cdm-storage kernel: i40iw_manage_apbvt: CQP-OP Manage APBVT entry fail Jul 12 00:49:25 cdm-storage kernel: i40iw_manage_apbvt: CQP-OP Manage APBVT entry fail Jul 12 00:49:25 cdm-storage kernel: workqueue: WQ_MEM_RECLAIM i40e:i40e_service_task [i40e] is flushing !WQ_MEM_RECLAIM infiniband:          (null) Jul 12 00:49:25 cdm-storage kernel: ------------[ cut here ]------------ Jul 12 00:49:25 cdm-storage kernel: WARNING: CPU: 8 PID: 411 at kernel/workqueue.c:2440 check_flush_dependency+0xb1/0x100 Jul 12 00:49:25 cdm-storage kernel: Modules linked in: iptable_raw xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 tun bridge stp llc ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter devlink qla2x00tgt(OE) scst_vdisk(OE) isert_scst(OE) iscsi_scst(OE) scst(OE) dlm libcrc32c rpcrdma bonding ib_iser libiscsi scsi_transport_iscsi ib_srp scsi_transport_srp ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm intel_rapl zfs(POE) skx_edac zunicode(POE) x86_pkg_temp_thermal zlua(POE) vfat fat coretemp crct10dif_pclmul crc32_pclmul zcommon(POE) znvpair(POE) zavl(POE) ghash_clmulni_intel pcbc i40iw icp(POE) aesni_intel spl(OE) ses enclosure crypto_simd glue_helper scsi_transport_sas Jul 12 00:49:25 cdm-storage kernel: iTCO_wdt qla2xxx_scst(OE) mei_me cryptd ib_core iTCO_vendor_support shannon(OE) sg scsi_transport_fc joydev mei pcspkr ioatdma shpchp i2c_i801 lpc_ich wmi ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter nfsd auth_rpcgss nfs_acl lockd sch_fq binfmt_misc grace sunrpc ip_tables sd_mod ast i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm ixgbe i40e ahci mdio libahci crc32c_intel megaraid_sas libata ptp dca i2c_core pps_core dm_mirror dm_region_hash dm_log dm_mod Jul 12 00:49:25 cdm-storage kernel: i40e 0000:1a:00.1: HMC error interrupt Jul 12 00:49:25 cdm-storage kernel: i40e 0000:1a:00.1: HMC error info 0x80160601, HMC error data 0x17f200 Jul 12 00:49:25 cdm-storage kernel: CPU: 8 PID: 411 Comm: kworker/8:1 Tainted: P        W  OE   4.14.44 #1 Jul 12 00:49:25 cdm-storage kernel: Hardware name: eCloudTech eCloudTech/Curry, BIOS 4.1.8 06/20/2019 Jul 12 00:49:25 cdm-storage kernel: Workqueue: i40e i40e_service_task [i40e] Jul 12 00:49:25 cdm-storage kernel: task: ffffa04bbe4c0000 task.stack: ffffc0568d684000 Jul 12 00:49:25 cdm-storage kernel: RIP: 0010:check_flush_dependency+0xb1/0x100 Jul 12 00:49:25 cdm-storage kernel: RSP: 0018:ffffc0568d687c50 EFLAGS: 00010246 Jul 12 00:49:25 cdm-storage kernel: RAX: 000000000000006f RBX: ffffa04ba920fe00 RCX: 0000000000000000 Jul 12 00:49:25 cdm-storage iscsi-scstd: Initiator iqn.1994-05.com.redhat:7b788ca34e34 not allowed to connect to target iqn.2016-07.com.ecloudtech:cdm-storage.stor Jul 12 00:49:25 cdm-storage kernel: RDX: 0000000000000000 RSI: ffffa04bbec169b8 RDI: ffffa04bbec169b8 Jul 12 00:49:25 cdm-storage kernel: RBP: ffffa00ddabd0000 R08: 0000000000000000 R09: 0000000000004351 Jul 12 00:49:25 cdm-storage kernel: R10: 00000000000003ff R11: 0000000000aaaaaa R12: 0000000000000000 Jul 12 00:49:25 cdm-storage kernel: R13: ffffa04a38e3785c R14: 0000000000000001 R15: ffffc0568d687c80 Jul 12 00:49:25 cdm-storage kernel: FS:  0000000000000000(0000) GS:ffffa04bbec00000(0000) knlGS:0000000000000000 Jul 12 00:49:25 cdm-storage kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Jul 12 00:49:25 cdm-storage kernel: CR2: 00007fb4a723f000 CR3: 0000003921e0a003 CR4: 00000000007606e0 Jul 12 00:49:25 cdm-storage kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 Jul 12 00:49:25 cdm-storage kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Jul 12 00:49:25 cdm-storage kernel: PKRU: 55555554 Jul 12 00:49:25 cdm-storage kernel: Call Trace: Jul 12 00:49:25 cdm-storage kernel: flush_workqueue+0x132/0x460 Jul 12 00:49:25 cdm-storage kernel: ib_cache_cleanup_one+0x21/0x30 [ib_core] Jul 12 00:49:25 cdm-storage kernel: ib_unregister_device+0x107/0x180 [ib_core] Jul 12 00:49:25 cdm-storage kernel: i40iw_destroy_rdma_device+0x61/0x170 [i40iw] Jul 12 00:49:25 cdm-storage kernel: ? ib_dispatch_event+0x3f/0x70 [ib_core] Jul 12 00:49:25 cdm-storage kernel: ? i40iw_port_ibevent+0x3f/0x60 [i40iw] Jul 12 00:49:25 cdm-storage kernel: i40iw_deinit_device+0x7e/0x370 [i40iw] Jul 12 00:49:25 cdm-storage kernel: i40e_notify_client_of_netdev_close+0x47/0x90 [i40e] Jul 12 00:49:25 cdm-storage kernel: i40e_service_task+0xb78/0x12f0 [i40e] Jul 12 00:49:25 cdm-storage kernel: ? __switch_to_asm+0x40/0x70 Jul 12 00:49:25 cdm-storage kernel: ? __switch_to_asm+0x34/0x70 Jul 12 00:49:25 cdm-storage kernel: ? __switch_to_asm+0x40/0x70 Jul 12 00:49:25 cdm-storage kernel: process_one_work+0x155/0x370 Jul 12 00:49:25 cdm-storage kernel: worker_thread+0x47/0x3e0 Jul 12 00:49:25 cdm-storage kernel: kthread+0xff/0x140 Jul 12 00:49:25 cdm-storage kernel: ? max_active_store+0x80/0x80 Jul 12 00:49:25 cdm-storage kernel: ? __kthread_parkme+0x70/0x70 Jul 12 00:49:25 cdm-storage kernel: ret_from_fork+0x35/0x40 Jul 12 00:49:25 cdm-storage kernel: Code: 9b 48 8b 55 18 48 8d 8b b0 00 00 00 48 81 c6 b0 00 00 00 4d 89 e0 48 c7 c7 90 f7 c6 89 31 c0 c6 05 22 43 35 01 01 e8 cc e6 03 00 <0f> 0b e9 6a ff ff ff 45 31 e4 e9 59 ff ff ff 31 ed eb 8e 80 3d  Jul 12 00:49:25 cdm-storage kernel: ---[ end trace 81d5684fa78a43bc ]--- Jul 12 00:49:25 cdm-storage kernel: i40iw_initialize_dev: DCB is set/clear = 0 Jul 12 00:49:25 cdm-storage kernel: i40iw_wait_pe_ready: [1261] fm load status[x0703] Jul 12 00:49:25 cdm-storage kernel: i40iw_wait_pe_ready: [1263] CSR_CQP status[x0080] Jul 12 00:49:25 cdm-storage kernel: i40iw_wait_pe_ready: [1266] I40E_GLPE_CPUSTATUS1 status[x0080] Jul 12 00:49:25 cdm-storage kernel: i40iw_wait_pe_ready: [1269] I40E_GLPE_CPUSTATUS2 status[x0080] Jul 12 00:49:25 cdm-storage kernel: bond0: link status definitely up for interface eth1, 1000 Mbps full duplex Jul 12 00:49:25 cdm-storage kernel: bond0: first active interface up!

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Kernel first task
by Anton Baltser July 12, 2021

July 12, 2021

Hello, I'm trying to get involved into Kernel Devolopment and confused about where I can take the first task to complete. AFAIK this is usually a code cleanup task, but what kind of code cleanup is available to do. Thanks! Regards,Anton Baltser.

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Hi All, I noticed soft lockup in fb_flashcursor(). What could be the problem? and how to resolve this?
by Oracle July 12, 2021

July 12, 2021

Linux kernel with centos(4.14.44 x86) ! The system log is as follows! Jul 12 05:00:18 cdm-storage kernel: [18578]: iscsi-scst: Freeing conn ffffa0447fb04440 (sess=ffffa03d40d4b300, 0x97fc0100003d0200 0, initiator iqn.1994-05.com.redhat:221930adcc15) Jul 12 05:00:18 cdm-storage kernel: [18578]: iscsi-scst: Freeing session ffffa03d40d4b300 (SID 97fc0100003d0200) Jul 12 05:00:18 cdm-storage kernel: [8032]: scst: Using security group "g-7bcce7ae" for initiator "iqn.1994-05.com.redhat:221930adcc15" (target iqn.2016-07.com.ecloudtech:cdm-storage.stor) Jul 12 05:00:18 cdm-storage kernel: watchdog: BUG: soft lockup - CPU#51 stuck for 22s! [kworker/51:1:24566] Jul 12 05:00:18 cdm-storage kernel: Modules linked in: iptable_raw xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 tun bridge stp llc ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter devlink qla2x00tgt(OE) scst_vdisk(OE) isert_scst(OE) iscsi_scst(OE) scst(OE) dlm libcrc32c rpcrdma bonding ib_iser libiscsi scsi_transport_iscsi ib_srp scsi_transport_srp ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm intel_rapl zfs(POE) skx_edac zunicode(POE) x86_pkg_temp_thermal zlua(POE) vfat fat coretemp crct10dif_pclmul crc32_pclmul zcommon(POE) znvpair(POE) zavl(POE) ghash_clmulni_intel pcbc i40iw icp(POE) aesni_intel spl(OE) ses enclosure crypto_simd glue_helper scsi_transport_sas Jul 12 05:00:18 cdm-storage kernel: iTCO_wdt qla2xxx_scst(OE) mei_me cryptd ib_core iTCO_vendor_support shannon(OE) sg scsi_transport_fc joydev mei pcspkr ioatdma shpchp i2c_i801 lpc_ich wmi ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter nfsd auth_rpcgss nfs_acl lockd sch_fq binfmt_misc grace sunrpc ip_tables sd_mod ast i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm ixgbe i40e ahci mdio libahci crc32c_intel megaraid_sas libata ptp dca i2c_core pps_core dm_mirror dm_region_hash dm_log dm_mod Jul 12 05:00:18 cdm-storage kernel: CPU: 51 PID: 24566 Comm: kworker/51:1 Tainted: P W OEL 4.14.44 #1 Jul 12 05:00:18 cdm-storage kernel: Hardware name: eCloudTech eCloudTech/Curry, BIOS 4.1.8 06/20/2019 Jul 12 05:00:18 cdm-storage kernel: Workqueue: events_power_efficient fb_flashcursor Jul 12 05:00:18 cdm-storage kernel: task: ffffa047ddec5a00 task.stack: ffffc0580c95c000 Jul 12 05:00:18 cdm-storage kernel: RIP: 0010:console_unlock+0x24e/0x4d0 Jul 12 05:00:18 cdm-storage kernel: RSP: 0018:ffffc0580c95fe38 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10 Jul 12 05:00:18 cdm-storage kernel: RAX: 0000000000000000 RBX: 00000000000000b1 RCX: 00000000ffffffff Jul 12 05:00:18 cdm-storage kernel: RDX: ffffc0580c95fde8 RSI: 0000000000000004 RDI: 0000000000000246 Jul 12 05:00:18 cdm-storage kernel: RBP: 0000000000000400 R08: 0000000000000000 R09: 0000000000000001 Jul 12 05:00:18 cdm-storage kernel: R10: 00000000000003ff R11: 0000000000aaaaaa R12: 0000000000000246 Jul 12 05:00:18 cdm-storage kernel: R13: 0000000000000000 R14: 00000000000000b1 R15: 0000000000000000 Jul 12 05:00:18 cdm-storage kernel: FS: 0000000000000000(0000) GS:ffffa04bbf6c0000(0000) knlGS:0000000000000000 Jul 12 05:00:18 cdm-storage kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Jul 12 05:00:18 cdm-storage kernel: CR2: 00007f8279c81000 CR3: 0000003921e0a003 CR4: 00000000007606e0 Jul 12 05:00:18 cdm-storage kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 Jul 12 05:00:18 cdm-storage kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Jul 12 05:00:18 cdm-storage kernel: PKRU: 55555554 Jul 12 05:00:18 cdm-storage kernel: Call Trace: Jul 12 05:00:18 cdm-storage kernel: process_one_work+0x155/0x370 Jul 12 05:00:18 cdm-storage kernel: worker_thread+0x47/0x3e0 Jul 12 05:00:18 cdm-storage kernel: kthread+0xff/0x140 Jul 12 05:00:18 cdm-storage kernel: ? max_active_store+0x80/0x80 Jul 12 05:00:18 cdm-storage kernel: ? __kthread_parkme+0x70/0x70 Jul 12 05:00:18 cdm-storage kernel: ret_from_fork+0x35/0x40 Jul 12 05:00:18 cdm-storage kernel: Code: 0f 84 b3 01 00 00 4c 89 ef 44 89 fa 48 c7 c6 80 d3 61 8a e8 45 3a b2 00 4d 8b 6d 50 4d 85 ed 75 a3 e8 37 17 00 00 4c 89 e7 57 9d <0f> 1f 44 00 00 8b 54 24 0c 85 d2 0f 84 23 fe ff ff e8 0c 07 73 Jul 12 05:00:18 cdm-storage kernel: [8032]: iscsi-scst: Session ffffa0448bbd3300 created: target ffffa04bb6de6600, tid 1, sid 0x97fe0100003d0200, initiator iqn.1994-05.com.redhat:221930adcc15 Jul 12 05:00:18 cdm-storage kernel: [8032]: iscsi-scst: Negotiated parameters: InitialR2T No, ImmediateData Yes, MaxConnections 1, MaxRecvDataSegmentLength 1048576, MaxXmitDataSegmentLength 262144,

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ioremap and page table
by ckim＠etri.re.kr July 12, 2021

July 12, 2021

Hello all, I'm almost sure but want to check if my understanding is correct. To use a memory mapped IO, we use functions like request_mem_region and ioremap, iounmap functions. I guess when we call ioremap function, the kernel sets up page table for the region so that the region becomes non-cacheable, and I don't also have to worry about reordering problem. Is my understanding correct? Thanks! Chan Kim

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KVM syscalls
by Simon Connah July 11, 2021

July 11, 2021

Hi, I hope this is an appropriate place to post this question. I want to make a very simple frontend to KVM, but I have no idea what syscalls the Linux kernel exposes to allow userspace programs to work with KVM virtual machines. Can someone point me in the right direction, please? I have no idea where to look for this information. Simon.

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Re: Kernel first task
by Anton Baltser July 10, 2021

July 10, 2021

Thanks Cláudio Maia, Extremely useful. I'd like to ask a question regarding Kernel bugzilla https://bugzilla.kernel.org/ . There are plenty of bugs there some of them are from more or less familar subsytems to me. Is it generally useful to pick a random bug from there and try to make up a patch? Regards,Anton Baltser. суббота, 10 июля 2021 г., 14:30:33 GMT+3, Cláudio Maia <clrrm(a)isep.ipp.pt> написал(-а): On 10/07/21 12:22, Anton Baltser wrote: > Hello, > > I'm trying to get involved into Kernel Devolopment and confused about where I can take the first task to complete. AFAIK this is usually a code cleanup task, but what kind of code cleanup is available to do. > > Thanks! > > Regards, > Anton Baltser. For an easy to follow introduction on how to submit your first patch, you can watch this talk (https://www.youtube.com/watch?v=LLBrBBImJt4) by Greg Kroah-Hartman at FOSDEM 2010 entitled "Write and Submit your first Linux kernel Patch". I believe this is a good starting point to guide through the process. Regards, Cláudio Maia

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laptop iwlwifi suddenly not working
by jim.cromie＠gmail.com July 8, 2021

July 8, 2021

while fumbling to pause grub during boot, I think I managed to disable the wifi. its affecting distro kernel, and my own booting with iwlwifi.debug=0xff on command line shows me iwl_pcie_apm_init Init card's basic functions reporting RF_KILL (radio disabled) It is reading that from somewhere, but where ? F12 has radio-beacon icon, pressing it causes WM to show Airplane mode, so that appears to be the rfr-kill switch dmesg -w shows me bluetooth going on and off, but no try to do so on iwlwifi are there other rf-switches ? I also tried reboot, F2 - (uefi bios) reset factory, reboot that obviously didnt help FWIW this laptop exhibits pcie correctable errors, I have pci=noaer in my boot line to ignore it. too long ? iirc, it was on same pcie port removing it doesnt help now,

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