This bug is awaiting verification that the linux- gkeop-5.15/5.15.0-1003.5~20.04.2 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-focal' to 'verification-done-focal'. If the problem still exists, change the tag 'verification-needed-focal' to 'verification-failed-focal'.
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you! -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1980951 Title: [UBUNTU 22.04] Kernel oops while removing device from cio_ignore list Status in Ubuntu on IBM z Systems: Fix Released Status in linux package in Ubuntu: Invalid Status in linux source package in Jammy: Fix Released Bug description: SRU Justification: ================== [Impact] * A kernel Oops occurs when a device is removed from the cio_ignore list (that is used to hide ccw devices) on a system with non-I/O subchannels (e.g. SCM or CHSC subchannels). * As a result, previously ignored devices cannot be activated again, and new devices cannot be found. [Fix] * 0c3812c347bf 0c3812c347bfb0dc213556a195e79850c55702f5 "s390/cio: derive cdev information only for IO-subchannels" [Test Plan] * An IBM zSystems or LinuxONE LPAR with with non-I/O subchannels. * Ubuntu Server 22.04 LTS (with GA kernel 5.15) installed. * Define a cio_ignore list (to hide ccw devices). * Remove a device from the cio_ignore list. * Due to hardware requirements this test needs to be conducted by IBM. [Where problems could occur] * General problems may occur with ccw device activation/deactivation in case the new initialization is erroneous. * Issues may also have an impact on the type of ccw devices, and may no longer be limited to non-I/O subchannels. * Things could still go wrong in case cdev is still not properly derived from sch-type SUBCHANNEL_TYPE_IO. [Other Info] * The commit is upstream since kernel 5.16 (next-20220315). __________ ---Problem Description from Peter--- A kernel oops occurs when a device is removed from the cio_ignore list on a system with non-I/O subchannels (e.g. SCM or CHSC subchannels). As a result, previously ignored devices cannot be activated, and new devices cannot be found. ---uname output--- Linux localhost 5.15.0-40-generic #43-Ubuntu SMP Wed Jun 15 12:53:53 UTC 2022 s390x s390x s390x GNU/Linux Machine Type = s390x ---Steps to Reproduce--- On an s390x-LPAR with non-I/O subchannels, remove a device from the cio_ignore list. Oops output: [ 51.597505] Unable to handle kernel pointer dereference in virtual kernel address space [ 51.597516] Failing address: 2081e99191e98000 TEID: 2081e99191e98803 [ 51.597520] Fault in home space mode while using kernel ASCE. [ 51.597524] AS:0000000082adc007 R3:0000000000000024 [ 51.597665] Oops: 0038 ilc:3 [#1] SMP [ 51.597671] Modules linked in: scm_block chsc_sch vfio_ccw mdev vfio_iommu_type1 vfio eadm_sch sch_fq_codel dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua drm i2c_core drm_panel_orientation_quirks ip_tables x_tables btrfs blake2b_generic zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_ xor async_tx xor raid6_pq libcrc32c raid1 raid0 linear pkey zcrypt crc32_vx_s390 ghash_s390 prng chacha_s390 libchacha aes_s390 des_s390 libdes qeth_l2 bridge stp llc zfcp qeth qdio scsi_transport_fc ccwgroup sha512_s390 sha256_s390 sha1_s390 sha_common [ 51.597735] CPU: 6 PID: 1418 Comm: cio_ignore Not tainted 5.15.0-40-generic #43-Ubuntu [ 51.597740] Hardware name: IBM 2964 NC9 702 (LPAR) [ 51.597742] Krnl PSW : 0704e00180000000 0000000081b0c632 (__unset_online+0x22/0x70) [ 51.597752] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 [ 51.597756] Krnl GPRS: 0000000000000001 00000000004a3ca8 0000038007e49000 2081e99191e98528 [ 51.597760] 0000000000000000 0000000081b0c610 0000000000000000 0000000081b07f10 [ 51.597762] 000002aa00000000 0000000081b0c610 0000038007e49000 0000038007a6bc98 [ 51.597765] 00000000941f9200 000003ffa8cf95e0 0000000081818900 0000038007a6bbf8 [ 51.597773] Krnl Code: 0000000081b0c624: a784000c brc 8,0000000081b0c63c [ 51.597773] 0000000081b0c628: e33030200002 ltg %r3,32(%r3) [ 51.597773] #0000000081b0c62e: a7840007 brc 8,0000000081b0c63c [ 51.597773] >0000000081b0c632: e33032000012 lt %r3,512(%r3) [ 51.597773] 0000000081b0c638: a7740007 brc 7,0000000081b0c646 [ 51.597773] 0000000081b0c63c: a7290000 lghi %r2,0 [ 51.597773] 0000000081b0c640: c0f400089854 brcl 15,0000000081c1f6e8 [ 51.597773] 0000000081b0c646: ebeff0880024 stmg %r14,%r15,136(%r15) [ 51.597818] Call Trace: [ 51.597820] [<0000000081b0c632>] __unset_online+0x22/0x70 [ 51.597824] ([<00000000818188e6>] bus_for_each_dev+0x66/0xc0) [ 51.597828] [<0000000081b0e378>] css_schedule_eval_cond+0xe8/0x130 [ 51.597832] [<0000000081b08062>] cio_ignore_write+0x152/0x190 [ 51.597838] [<00000000814be36e>] proc_reg_write+0x9e/0xf0 [ 51.597843] [<00000000813f3470>] vfs_write+0xc0/0x280 [ 51.597848] [<00000000813f59a8>] ksys_write+0x68/0x100 [ 51.597852] [<0000000081b495d0>] __do_syscall+0x1c0/0x1f0 [ 51.597857] [<0000000081b56858>] system_call+0x78/0xa0 [ 51.597862] Last Breaking-Event-Address: [ 51.597864] [<000000000000a000>] 0xa000 [ 51.597868] ---[ end trace 166ba86e913d2c60 ]--- To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1980951/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
