[Bug 2163945] Re: [Noble HWE 7.0][amdgpu][RX 6650 XT] Intermittent poweroff hang; 6.14.0-37 works, 7.0.0-28 and 7.0.0-29 fail

** Tags added: kernel-daily-bug -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2163945 Title: [Noble HWE 7.0][amdgpu][RX 6650 XT] Intermittent poweroff hang; 6.14.0-37 works, 7.0.0-28 and 7.0.0-29 fail Status in linux package in Ubuntu: New Bug description: **Title** [Noble HWE 7.0][amdgpu][RX 6650 XT] Intermittent poweroff hang; 6.14.0-37 works, 7.0.0-28 and 7.0.0-29 fail **Description** I am experiencing an intermittent shutdown/poweroff hang after moving from the Ubuntu Noble HWE 6.14 kernel to HWE 7.0. The issue is reproducible with both: * linux-image-7.0.0-28-generic 7.0.0-28.28~24.04.1 * linux-image-7.0.0-29-generic 7.0.0-29.29~24.04.2 The same machine shuts down reliably with: * linux-image-6.14.0-37-generic 6.14.0-37.37~24.04.1 **Hardware** Motherboard: Gigabyte B550M DS3H rev. 1.4 BIOS: FF, 2025-10-28 GPU: AMD Radeon RX 6650 XT (Navi 23), amdgpu driver **Observed behaviour** When the problem occurs, shutdown starts normally and the displays turn off, but the computer does not complete the physical power-off. Reboot does not exhibit the issue. I have never reproduced the problem when rebooting the machine. The issue can also occur with: `sudo poweroff -f` This suggests that the problem is not simply caused by a userspace service failing to stop. **Kernel comparison** 6.14.0-37-generic: Poweroff works reliably. 7.0.0-28-generic: Intermittent poweroff hang. 7.0.0-29-generic: Intermittent poweroff hang. Reboot with the 7.0 kernels: Always works. This therefore appears to be a regression introduced between the Ubuntu HWE 6.14 and HWE 7.0 kernel series. **Shutdown logs** During a failed shutdown, userspace shutdown proceeds normally. Docker completes its shutdown successfully and NetworkManager exits successfully. The journal reaches the final `systemd-shutdown` stage: `systemd-shutdown[1]: Syncing filesystems and block devices.` `systemd-shutdown[1]: Sending SIGTERM to remaining processes...` The journal then stops as expected when systemd-journald is terminated. Shortly before this final shutdown phase, the kernel repeatedly reports messages similar to: `workqueue: drm_fb_helper_damage_work hogged CPU for >10000us, consider switching to WQ_UNBOUND` I do not know whether this DRM warning is causal, but I am mentioning it because it occurs immediately around the shutdown sequence on the affected kernels. **Related AMD shutdown fix** Ubuntu kernel 6.14.0-37 includes the fixes for LP #2115860 (“Poweroff not working consistently”), including several drm/amd shutdown/S5 fixes. However, the relevant shutdown/S5 behaviour appears to already exist in upstream Linux 7.0, so this does not appear to be simply a missing backport of LP #2115860. It may instead be a new regression in the 7.0 kernel series or an interaction exposed by later DRM/AMDGPU changes. **Steps to reproduce** 1. Boot kernel 7.0.0-28-generic or 7.0.0-29-generic. 2. Use the system normally. 3. Request a normal shutdown. 4. Intermittently, the displays turn off but the machine does not complete power-off. The same test has not reproduced the issue under 6.14.0-37-generic. **Expected result** The machine should completely power off. **Actual result** The shutdown sequence reaches its final stage, but the machine intermittently remains powered instead of completing power-off. --- ProblemType: Bug ApportVersion: 2.28.3-0ubuntu0.1 Architecture: amd64 CRDA: N/A CasperMD5CheckMismatches: ./boot/grub/efi.img CasperMD5CheckResult: fail CurrentDesktop: X-Cinnamon DistroRelease: Linux Mint 22.3 InstallationDate: Installed on 2026-07-22 (27 days ago) InstallationMedia: Linux Mint 22.3 "Zena" - Release amd64 20260108 IwConfig: lo no wireless extensions. enp6s0 no wireless extensions. docker0 no wireless extensions. MachineType: Gigabyte Technology Co., Ltd. B550M DS3H Package: linux (not installed) ProcFB: 0 amdgpudrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-7.0.0-29-generic root=UUID=94102f42-dca2-4dbb-a722-190ea16c6d05 ro amdgpu.runpm=0 systemd.log_level=debug systemd.log_target=kmsg printk.devkmsg=on ignore_loglevel ProcVersionSignature: Ubuntu 7.0.0-29.29~24.04.2-generic 7.0.12 PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon. RelatedPackageVersions: linux-restricted-modules-7.0.0-29-generic N/A linux-backports-modules-7.0.0-29-generic N/A linux-firmware 20240318.git3b128b60-0ubuntu2.29 RfKill: Tags: zena Uname: Linux 7.0.0-29-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dialout dip docker i2c lpadmin ollama plugdev render sambashare sudo users video _MarkForUpload: True dmi.bios.date: 10/28/2025 dmi.bios.release: 5.17 dmi.bios.vendor: American Megatrends International, LLC. dmi.bios.version: FF dmi.board.asset.tag: Default string dmi.board.name: B550M DS3H dmi.board.vendor: Gigabyte Technology Co., Ltd. dmi.board.version: x.x dmi.chassis.asset.tag: Default string dmi.chassis.type: 3 dmi.chassis.vendor: Default string dmi.chassis.version: Default string dmi.modalias: dmi:bvnAmericanMegatrendsInternational,LLC.:bvrFF:bd10/28/2025:br5.17:svnGigabyteTechnologyCo.,Ltd.:pnB550MDS3H:pvrDefaultstring:rvnGigabyteTechnologyCo.,Ltd.:rnB550MDS3H:rvrx.x:cvnDefaultstring:ct3:cvrDefaultstring:skuDefaultstring:pfaB550MB: dmi.product.family: B550 MB dmi.product.name: B550M DS3H dmi.product.sku: Default string dmi.product.version: Default string dmi.sys.vendor: Gigabyte Technology Co., Ltd. --- ProblemType: Bug ApportVersion: 2.28.3-0ubuntu0.1 Architecture: amd64 CRDA: N/A CasperMD5CheckMismatches: ./boot/grub/efi.img CasperMD5CheckResult: fail CurrentDesktop: X-Cinnamon DistroRelease: Linux Mint 22.3 InstallationDate: Installed on 2026-07-22 (27 days ago) InstallationMedia: Linux Mint 22.3 "Zena" - Release amd64 20260108 IwConfig: lo no wireless extensions. enp6s0 no wireless extensions. docker0 no wireless extensions. MachineType: Gigabyte Technology Co., Ltd. B550M DS3H Package: linux (not installed) ProcFB: 0 amdgpudrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-7.0.0-29-generic root=UUID=94102f42-dca2-4dbb-a722-190ea16c6d05 ro amdgpu.runpm=0 systemd.log_level=debug systemd.log_target=kmsg printk.devkmsg=on ignore_loglevel ProcVersionSignature: Ubuntu 7.0.0-29.29~24.04.2-generic 7.0.12 PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon. RelatedPackageVersions: linux-restricted-modules-7.0.0-29-generic N/A linux-backports-modules-7.0.0-29-generic N/A linux-firmware 20240318.git3b128b60-0ubuntu2.29 RfKill: Tags: zena Uname: Linux 7.0.0-29-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dialout dip docker i2c lpadmin ollama plugdev render sambashare sudo users video _MarkForUpload: True dmi.bios.date: 10/28/2025 dmi.bios.release: 5.17 dmi.bios.vendor: American Megatrends International, LLC. dmi.bios.version: FF dmi.board.asset.tag: Default string dmi.board.name: B550M DS3H dmi.board.vendor: Gigabyte Technology Co., Ltd. dmi.board.version: x.x dmi.chassis.asset.tag: Default string dmi.chassis.type: 3 dmi.chassis.vendor: Default string dmi.chassis.version: Default string dmi.modalias: dmi:bvnAmericanMegatrendsInternational,LLC.:bvrFF:bd10/28/2025:br5.17:svnGigabyteTechnologyCo.,Ltd.:pnB550MDS3H:pvrDefaultstring:rvnGigabyteTechnologyCo.,Ltd.:rnB550MDS3H:rvrx.x:cvnDefaultstring:ct3:cvrDefaultstring:skuDefaultstring:pfaB550MB: dmi.product.family: B550 MB dmi.product.name: B550M DS3H dmi.product.sku: Default string dmi.product.version: Default string dmi.sys.vendor: Gigabyte Technology Co., Ltd. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2163945/+subscriptions

[Bug 2163620] Re: [Ubuntu 26.10] : KVM guest boot hangs on POWER11 host when processor compatibility mode is set to POWER10

** Tags added: kernel-daily-bug -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2163620 Title: [Ubuntu 26.10] : KVM guest boot hangs on POWER11 host when processor compatibility mode is set to POWER10 Status in linux package in Ubuntu: In Progress Status in linux source package in Stonking: In Progress Bug description: [Impact] On a POWER11 system with the processor compatibility mode set to POWER10, Ubuntu 26.10 guest installation fails to boot on a KVM-enabled host. When a guest is created using virt-install and booted from the Ubuntu 26.10 installation ISO, the boot process hangs during early kernel initialization and the installer does not proceed further. [Fix] Apply the following patches from linux-next: - 884ea0283f4e KVM: PPC: Book3S HV: Validate arch_compat against host compatibility mode - ac3e65ddddf3 KVM: PPC: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl - b76fb087efcd KVM: PPC: Book3S HV: Implement compat CPU capability retrieval for KVM on PowerVM - 8735048f54ec KVM: PPC: Book3S HV: Add support for compat CPU capabilities for KVM on PowerNV - c1721e584244 KVM: PPC: Document KVM_PPC_GET_COMPAT_CAPS ioctl [Test Plan] - Setup KVM enabled host with Ubuntu26.10. - Install libvirt and qemu packages required for bringing up GUests - Create and boot an Ubuntu 26.10 KVM guest from the Ubuntu 26.10 installation ISO on a POWER11 LPAR running in POWER10 compatibility mode using the following command: ``` /usr/bin/virt-install --connect=qemu:///system --hvm --accelerate --name 'vm' --machine pseries --memory=10000 --vcpu=10,sockets=1,cores=10,threads=1 --import --nographics --os-variant ubuntu25.10 --serial pty --memballoon model=virtio --controller type=scsi,model=virtio-scsi --disk path=/home/ubuntu26_10.qcow2,bus=scsi,size=50,format=qcow2 --network=bridge=virbr0,model=virtio --boot emulator=/usr/bin/qemu-system-ppc64 --cdrom /home/ubuntu-26.10-snapshot2-live-server-ppc64el.iso ``` [Regression Potential] The change is confined to powerpc nested virtualization code. Users of nested virtualization in powerpc may be affected. --- == Problem Description === On a POWER11 system with the processor compatibility mode set to POWER10, Ubuntu 26.10 guest installation fails to boot on a KVM-enabled host. When a guest is created using virt-install and booted from the Ubuntu 26.10 installation ISO, the boot process hangs during early kernel initialization and the installer does not proceed further. HOST ENV: OS : Ubuntu 26.10 (Stonking Stingray) kernel : 7.0.0-14-generic libvirt : libvirtd (libvirt) 12.0.0 qemu : QEMU emulator version 10.2.1 on host : # lscpu Architecture: ppc64le   Byte Order: Little Endian CPU(s): 80   On-line CPU(s) list: 0-79 Model name: POWER10 (architected), altivec supported   Model: 2.0 (pvr 0082 0200)   Thread(s) per core: 8   Core(s) per socket: 10   Socket(s): 1 Virtualization features:   Hypervisor vendor: pHyp   Virtualization type: para Caches (sum of all):   L1d: 640 KiB (20 instances)   L1i: 960 KiB (20 instances)   L2: 20 MiB (20 instances)   L3: 80 MiB (20 instances) NUMA:   NUMA node(s): 3   NUMA node0 CPU(s):   NUMA node1 CPU(s): 0-79   NUMA node2 CPU(s): Vulnerabilities:   Gather data sampling: Not affected   Ghostwrite: Not affected   Indirect target selection: Not affected   Itlb multihit: Not affected   L1tf: Not affected   Mds: Not affected   Meltdown: Not affected   Mmio stale data: Not affected   Old microcode: Not affected   Reg file data sampling: Not affected   Retbleed: Not affected   Spec rstack overflow: Not affected   Spec store bypass: Not affected   Spectre v1: Mitigation; __user pointer sanitization, ori31 speculation barrier enabled   Spectre v2: Mitigation; Software count cache flush (hardware accelerated), Software link stack flush   Srbds: Not affected   Tsa: Not affected   Tsx async abort: Not affected   Vmscape: Not affected Steps to re-create: =================== - Setup KVM enabled host with Ubuntu26.10. - Install libvirt and qemu packages required for bringing up GUests - Create and boot an Ubuntu 26.10 KVM guest from the Ubuntu 26.10 installation ISO on a POWER11 LPAR running in POWER10 compatibility mode using the following command: --logs-- /usr/bin/virt-install --connect=qemu:///system --hvm --accelerate --name 'vm' --machine pseries --memory=10000 --vcpu=10,sockets=1,cores=10,threads=1 --import --nographics --os-variant ubuntu25.10 --serial pty --memballoon model=virtio --controller type=scsi,model=virtio-scsi --disk path=/home/ubuntu26_10.qcow2,bus=scsi,size=50,format=qcow2 --network=bridge=virbr0,model=virtio --boot emulator=/usr/bin/qemu-system-ppc64 --cdrom /home/ubuntu-26.10-snapshot2-live-server-ppc64el.iso WARNING CDROM media does not print to the text console by default, so you likely will not see text install output. You might want to use --location. See the man page for examples of using --location with CDROM media Starting install... Allocating 'ubuntu26_10.qcow2' | 50 GB 00:00:00 Creating domain... | 00:00:00 Running text console command: virsh --connect qemu:///system console vm Connected to domain 'vm' Escape character is ^] (Ctrl + ]) Populating /vdevice methods Populating /vdevice/vty@30000000 Populating /vdevice/nvram@71000000 Populating /pci@800000020000000                      00 0800 (D) : 1af4 1000 virtio [ net ]                      00 1000 (D) : 1af4 1004 virtio [ scsi ] Populating /pci@800000020000000/scsi@2        SCSI: Looking for devices           100000000000000 DISK : "QEMU QEMU HARDDISK 2.5+"           100000100000000 CD-ROM : "QEMU QEMU CD-ROM 2.5+"                      00 1800 (D) : 1b36 000d serial bus [ usb-xhci ]                      00 2000 (D) : 1af4 1003 virtio [ serial ]                      00 2800 (D) : 1af4 1002 legacy-device*                      00 3000 (D) : 1af4 1005 legacy-device* No NVRAM common partition, re-initializing... Scanning USB   XHCI: Initializing Using default console: /vdevice/vty@30000000   Welcome to Open Firmware   Copyright (c) 2004, 2017 IBM Corporation All rights reserved.   This program and the accompanying materials are made available   under the terms of the BSD License available at   http://www.opensource.org/licenses/bsd-license.php Trying to load: from: /pci@800000020000000/scsi@2/disk@100000100000000 ... Successfully loaded Welcome to GRUB! error: couldn't examine /ibm,secure-boot property. error: unrecognized number.                              GNU GRUB version 2.14  +----------------------------------------------------------------------------+  |*Try or Install Ubuntu Server |  | |  | |  | |  | |  | |  | |  | |  | |  | |  | |  | |  +----------------------------------------------------------------------------+       Use the ^ and v keys to select which entry is highlighted.       Press enter to boot the selected OS, `e' to edit the commands       before booting or `c' for a command-line. OF stdout device is: /vdevice/vty@30000000 Preparing to boot Linux version 7.0.0-14-generic (buildd@bos03-ppc64el-029) (powerpc64le-linux-gnu-gcc (Ubuntu 15.2.0-16ubuntu1) 15.2.0, GNU ld (GNU Binutils for Ubuntu) 2.46) #14-Ubuntu SMP PREEMPT_DYNAMIC Mon Apr 13 11:10:37 UTC 2026 (Ubuntu 7.0.0-14.14-generic 7.0.0) Detected machine type: 0000000000000101 command line: BOOT_IMAGE=/casper/vmlinux quiet --- Max number of cores passed to firmware: 2048 (NR_CPUS = 2048) Calling ibm,client-architecture-support... == Comment: #2 == The patches are in ppc next now: c1721e584244 KVM: PPC: Document KVM_PPC_GET_COMPAT_CAPS ioctl 8735048f54ec KVM: PPC: Book3S HV: Add support for compat CPU capabilities for KVM on PowerNV b76fb087efcd KVM: PPC: Book3S HV: Implement compat CPU capability retrieval for KVM on PowerVM ac3e65ddddf3 KVM: PPC: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl 884ea0283f4e KVM: PPC: Book3S HV: Validate arch_compat against host compatibility mode Please note that one of the dependent patches had already made it to upstream. e4de1b9cb3b5 ("powerpc/dt_cpu_ftrs: Set CPU_FTR_P11_PVR for Power11 and later processors") To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2163620/+subscriptions

[Bug 2163714] Re: oops in shrink_folio_list(): out-of-bounds read of folio->_deferred_list

** Tags added: kernel-daily-bug -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2163714 Title: oops in shrink_folio_list(): out-of-bounds read of folio->_deferred_list Status in linux package in Ubuntu: New Status in linux-azure-6.8 package in Ubuntu: New Bug description: [Expected] Page-cache reclaim runs without faulting, regardless of the upper MMIO region splitting System RAM. [What's happened] Three of our Azure VMs (`Standard_L16as_v4` with the upper MMIO region below `0x1000000000` on `linux-azure-6.8 6.8.0-1062.69~22.04.1`) running as Elasticsearch data-nodes oopsed - two in kswapd0, one in the elasticsearch process itself. Crashed machines were rebuilt urgently, non-crashed ones a bit later, so we got apport and /proc/iomem from them: - oops-node1-kswapd.log # fragment from crashed node - oops-node2-kswapd.log # fragment from crashed node - oops-node3-elasticsearch.log # fragment from crashed node - proc-iomem-node4.log # output of same set machine, not crashed - apport-node4.txt # apport of same set machine, not crashed [Suspect] An oops in `shrink_folio_list()`. [Steps to reproduce] ./reproduce.sh azure-1062 # or: noble-31 noble-137 noble-139 azure-1064 azure-1062-read-deleted azure-1062-mglru-off The script fetches the kernel from Launchpad, builds a rootfs, and boots QEMU: 4 GiB guest, 4 x 128 MB holes via `memmap=`, XFS on /dev/vda with a 16 GiB file, read via mmap with jumps to random offsets. Ext4 is untested. [Versions tested] target kernel result log noble-31 linux 6.8.0-31.31 no oops, 5,000,000 jumps reproduce-noble-31.log noble-137 linux 6.8.0-137.137 oops, before jump 200,000 reproduce-noble-137.log noble-139 linux 6.8.0-139.139 (proposed) oops, before jump 400,000 reproduce-noble-139.log azure-1062 linux-azure-6.8 1062.69~22.04.1 oops, before jump 200,000 reproduce-azure-1062.log azure-1064 linux-azure-6.8 1064.72~22.04.1 oops, before jump 800,000 reproduce-azure-1064.log azure-1062-read-deleted rebuilt from 1062 source no oops, 5,000,000 jumps reproduce-azure-1062-read-deleted.log azure-1062-mglru-off rebuilt from 1062 source oops, before jump 800,000 reproduce-azure-1062-mglru-off.log In most of these runs the fault came twice: first in kswapd0, then in the reading process itself. This matches both patterns we saw in production. All these logs come from runs with 4 holes and a limit of 5,000,000 jumps. Fewer holes make the fault less likely - with a single hole we still got it, but the run took much longer. With 4 holes a bad kernel faults in minutes, so we did not have to run each version for days. We can run more tests if needed. 137.137 (noble Updates) and 1064.72 (jammy Updates) are the newest published builds; 31.31 is noble Release before the backport named under [Cause]. [Cause] Probably it's in `mm/vmscan.c:1277` if (folio_test_large(folio) && list_empty(&folio->_deferred_list)) flags |= TTU_SYNC; The line appeared in `Ubuntu-6.8.0-48.48` with the backport for LP #2076147. 73bc32875ee9 mm: hold PTL from the first PTE while reclaiming a large folio Mainline dropped it - it seems that wasn't backported. e5a119c4a683 mm/vmscan: drop checking if _deferred_list is empty before using TTU_SYNC The `azure-1062-read-deleted` target applies exactly this one-line removal. If we filed this against the wrong package, or if you need anything else from us, please let us know. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2163714/+subscriptions

[Bug 2163363] Re: [amdgpu/ttm] TTM list corruption and NULL dereference under GPU memory pressure on ASUS ProArt PX13 (7.0.0-29)

** Attachment added: "linux-image-7.0.0-29-generic-202608161036.crash" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2163363/+attachment/5993400/+files/linux-image-7.0.0-29-generic-202608161036.crash -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2163363 Title: [amdgpu/ttm] TTM list corruption and NULL dereference under GPU memory pressure on ASUS ProArt PX13 (7.0.0-29) Status in linux package in Ubuntu: Incomplete Bug description: An ASUS ProArt PX13 HN7306EAC with an AMD integrated GPU (PCI ID 1002:1586) repeatedly experienced kernel-side TTM/AMDGPU corruption and complete graphical failure while running Ubuntu 26.04 kernel 7.0.0-29-generic. The failures occurred with different visible userspace processes. They are therefore reported as possible triggers, not assumed root causes. FIRST HARD FREEZE / NULL DEREFERENCE A complete desktop freeze required a hard reset. The first fatal event was: BUG: kernel NULL pointer dereference, address: 0000000000000019 Comm: ptyxis RIP: ttm_lru_bulk_move_pos_tail+0x53/0xd0 [ttm] Relevant call path: ttm_resource_add_bulk_move ttm_bo_populate ttm_bo_vm_fault_reserved amdgpu_gem_fault A previous occurrence involved firefox:gl0 and failed in the same TTM/AMDGPU resource-management area. LATER TTM LIST CORRUPTION Immediately before the warnings, the kernel repeatedly logged: amdgpu_vm_validate() failed. Not enough memory for command submission! This was followed by: list_add corruption list_del corruption Relevant call paths included: ttm_resource_move_to_lru_tail ttm_bo_populate ttm_bo_vm_fault_reserved amdgpu_gem_fault and: ttm_resource_fini ttm_resource_free amdgpu_bo_move amdgpu_cs_bo_validate amdgpu_cs_ioctl LATER GRAPHICAL-SESSION FAILURE AMDGPU again rejected command submissions with -12. GNOME Shell then aborted with SIGABRT in Mesa Gallium, closing the Wayland session and all terminal applications. This event was a graphical-session restart, not a full machine reboot. ENVIRONMENT Hardware: ASUS ProArt PX13 HN7306EAC CPU/GPU: AMD Ryzen AI Max+ 395 / Radeon 8060S GPU PCI ID: 1002:1586 BIOS: HN7306EAC.307 (2026-01-27) RAM: 128 GB shared system/GPU memory Distribution: Ubuntu 26.04 Kernel: 7.0.0-29-generic, package 7.0.0-29.29 (upstream base 7.0.12) Desktop: GNOME on Wayland WORKLOAD / POSSIBLE TRIGGER Local llama.cpp/Vulkan language-model workloads and desktop applications were active. They use shared system/GPU memory and may increase memory pressure. This is reported as a possible trigger only, not as a demonstrated root cause. NEGATIVE EVIDENCE The inspected logs before the first Oops did not show an OOM kill, MCE, thermal shutdown, PCIe AER error, GPU ring timeout, or GPU reset. The kernel was not tainted before the first Oops. EXPECTED RESULT Userspace GPU activity or memory pressure must not corrupt TTM lists, trigger a kernel NULL pointer dereference, or terminate the graphical session. PRIVACY No vmcore, dump-incomplete, or full memory image is attached because those artifacts may contain credentials, documents, medical data, and browser contents. RELATED REPORT A public report with a similar ttm_lru_bulk_move_pos_tail signature and hard desktop freeze is available at: https://github.com/basecamp/omarchy/issues/6443 --- ProblemType: Bug ApportVersion: 2.34.1-0ubuntu0.1 Architecture: amd64 CasperMD5CheckResult: pass CurrentDesktop: ubuntu:GNOME DistroRelease: Ubuntu 26.04 InstallationDate: Installed on 2026-08-01 (15 days ago) InstallationMedia: Ubuntu 26.04 "Resolute Raccoon" - Release amd64 (20260423.1) MachineType: ASUS ProArt PX13 HN7306EAC Package: linux (not installed) ProcEnviron: LANG=es_ES.UTF-8 PATH=(custom, no user) SHELL=/bin/bash TERM=xterm-256color XDG_RUNTIME_DIR=<set> ProcFB: 0 amdgpudrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-7.0.0-29-generic root=UUID=80141fa6-a50a-4bc8-816b-cc4d43d1fa74 ro quiet splash crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M ProcVersionSignature: Ubuntu 7.0.0-29.29-generic 7.0.12 Tags: resolute wayland-session Uname: Linux 7.0.0-29-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin lxd plugdev sudo users _MarkForUpload: True dmi.bios.date: 01/27/2026 dmi.bios.release: 5.36 dmi.bios.vendor: American Megatrends International, LLC. dmi.bios.version: HN7306EAC.307 dmi.board.asset.tag: ATN12345678901234567 dmi.board.name: HN7306EAC dmi.board.vendor: ASUSTeK COMPUTER INC. dmi.board.version: 1.0 dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 31 dmi.chassis.vendor: ASUSTeK COMPUTER INC. dmi.chassis.version: 1.0 dmi.ec.firmware.release: 3.6 dmi.modalias: dmi:bvnAmericanMegatrendsInternational,LLC.:bvrHN7306EAC.307:bd01/27/2026:br5.36:efr3.6:svnASUS:pnProArtPX13HN7306EAC:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnHN7306EAC:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct31:cvr1.0:sku:pfaProArtPX13: dmi.product.family: ProArt PX13 dmi.product.name: ProArt PX13 HN7306EAC dmi.product.version: 1.0 dmi.sys.vendor: ASUS To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2163363/+subscriptions

[Bug 2163363] Re: [amdgpu/ttm] TTM list corruption and NULL dereference under GPU memory pressure on ASUS ProArt PX13 (7.0.0-29)

I appear to be seeing the same issue. Below is output from Claude after long debugging session. Please let me know if I can provide additional debug info: Reproducing this same TTM bulk-move list corruption / NULL pointer crash on different hardware — Framework Laptop 13 (AMD Ryzen AI 300 Series), Ryzen AI 7 350, Radeon 860M (gfx_v11 / DCN 3.5), same kernel build 7.0.0-29-generic on Ubuntu 26.04. Linux Freya 7.0.0-29-generic #29-Ubuntu SMP PREEMPT_DYNAMIC Fri Jul 17 20:52:35 UTC 2026 x86_64 GNU/Linux Description: Ubuntu 26.04 LTS ii linux-image-7.0.0-29-generic 7.0.0-29.29 amd64 Signed kernel image generic Multiple independent crashes so far, both NULL derefs in ttm_lru_bulk_move_tail via the same amdgpu command-submission path: Crash 1 (triggered by Papers/PDF viewer during normal use): RIP: ttm_lru_bulk_move_tail+0x1a5/0x360 [ttm] CR2: 0000000000000008 Call Trace: amdgpu_vm_move_to_lru_tail -> amdgpu_cs_submit -> amdgpu_cs_ioctl -> amdgpu_drm_ioctl Crash 2 (triggered by a terminal app (ptyxis), immediately after resuming from suspend-then-hibernate): RIP: ttm_lru_bulk_move_tail+0x15c/0x360 [ttm] CR2: 0000000000000180 Call Trace: amdgpu_vm_move_to_lru_tail -> amdgpu_cs_submit -> amdgpu_cs_ioctl -> amdgpu_drm_ioctl Same crash site, different offset/address each time, different triggering app both times — looks like a race rather than a deterministic bug. Notably, in my case the crash appears strongly correlated with resume from suspend/hibernate: the first GPU command submitted by whatever app happens to run right after resume is what crashes, which fits ttm_lru_bulk_move_pos_tail/ttm_lru_bulk_move_tail sharing the same underlying bulk-move list corruption this bug describes, just hit via a different sibling function. Happy to test a kernel with Thomas Hellstrom's candidate patch (https://lore.kernel.org/all/20260714141400.20904-1-thomas.hellstrom@linux.intel.com/) if that would help move this forward — let me know how to build/obtain a test kernel. Full crash reports (apport) attached: linux-image-7.0.0-29-generic-202608161036.crash, linux-image-7.0.0-29-generic-202608182014.crash ** Attachment added: "linux-image-7.0.0-29-generic-202608112328.crash" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2163363/+attachment/5993399/+files/linux-image-7.0.0-29-generic-202608112328.crash -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2163363 Title: [amdgpu/ttm] TTM list corruption and NULL dereference under GPU memory pressure on ASUS ProArt PX13 (7.0.0-29) Status in linux package in Ubuntu: Incomplete Bug description: An ASUS ProArt PX13 HN7306EAC with an AMD integrated GPU (PCI ID 1002:1586) repeatedly experienced kernel-side TTM/AMDGPU corruption and complete graphical failure while running Ubuntu 26.04 kernel 7.0.0-29-generic. The failures occurred with different visible userspace processes. They are therefore reported as possible triggers, not assumed root causes. FIRST HARD FREEZE / NULL DEREFERENCE A complete desktop freeze required a hard reset. The first fatal event was: BUG: kernel NULL pointer dereference, address: 0000000000000019 Comm: ptyxis RIP: ttm_lru_bulk_move_pos_tail+0x53/0xd0 [ttm] Relevant call path: ttm_resource_add_bulk_move ttm_bo_populate ttm_bo_vm_fault_reserved amdgpu_gem_fault A previous occurrence involved firefox:gl0 and failed in the same TTM/AMDGPU resource-management area. LATER TTM LIST CORRUPTION Immediately before the warnings, the kernel repeatedly logged: amdgpu_vm_validate() failed. Not enough memory for command submission! This was followed by: list_add corruption list_del corruption Relevant call paths included: ttm_resource_move_to_lru_tail ttm_bo_populate ttm_bo_vm_fault_reserved amdgpu_gem_fault and: ttm_resource_fini ttm_resource_free amdgpu_bo_move amdgpu_cs_bo_validate amdgpu_cs_ioctl LATER GRAPHICAL-SESSION FAILURE AMDGPU again rejected command submissions with -12. GNOME Shell then aborted with SIGABRT in Mesa Gallium, closing the Wayland session and all terminal applications. This event was a graphical-session restart, not a full machine reboot. ENVIRONMENT Hardware: ASUS ProArt PX13 HN7306EAC CPU/GPU: AMD Ryzen AI Max+ 395 / Radeon 8060S GPU PCI ID: 1002:1586 BIOS: HN7306EAC.307 (2026-01-27) RAM: 128 GB shared system/GPU memory Distribution: Ubuntu 26.04 Kernel: 7.0.0-29-generic, package 7.0.0-29.29 (upstream base 7.0.12) Desktop: GNOME on Wayland WORKLOAD / POSSIBLE TRIGGER Local llama.cpp/Vulkan language-model workloads and desktop applications were active. They use shared system/GPU memory and may increase memory pressure. This is reported as a possible trigger only, not as a demonstrated root cause. NEGATIVE EVIDENCE The inspected logs before the first Oops did not show an OOM kill, MCE, thermal shutdown, PCIe AER error, GPU ring timeout, or GPU reset. The kernel was not tainted before the first Oops. EXPECTED RESULT Userspace GPU activity or memory pressure must not corrupt TTM lists, trigger a kernel NULL pointer dereference, or terminate the graphical session. PRIVACY No vmcore, dump-incomplete, or full memory image is attached because those artifacts may contain credentials, documents, medical data, and browser contents. RELATED REPORT A public report with a similar ttm_lru_bulk_move_pos_tail signature and hard desktop freeze is available at: https://github.com/basecamp/omarchy/issues/6443 --- ProblemType: Bug ApportVersion: 2.34.1-0ubuntu0.1 Architecture: amd64 CasperMD5CheckResult: pass CurrentDesktop: ubuntu:GNOME DistroRelease: Ubuntu 26.04 InstallationDate: Installed on 2026-08-01 (15 days ago) InstallationMedia: Ubuntu 26.04 "Resolute Raccoon" - Release amd64 (20260423.1) MachineType: ASUS ProArt PX13 HN7306EAC Package: linux (not installed) ProcEnviron: LANG=es_ES.UTF-8 PATH=(custom, no user) SHELL=/bin/bash TERM=xterm-256color XDG_RUNTIME_DIR=<set> ProcFB: 0 amdgpudrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-7.0.0-29-generic root=UUID=80141fa6-a50a-4bc8-816b-cc4d43d1fa74 ro quiet splash crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M ProcVersionSignature: Ubuntu 7.0.0-29.29-generic 7.0.12 Tags: resolute wayland-session Uname: Linux 7.0.0-29-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin lxd plugdev sudo users _MarkForUpload: True dmi.bios.date: 01/27/2026 dmi.bios.release: 5.36 dmi.bios.vendor: American Megatrends International, LLC. dmi.bios.version: HN7306EAC.307 dmi.board.asset.tag: ATN12345678901234567 dmi.board.name: HN7306EAC dmi.board.vendor: ASUSTeK COMPUTER INC. dmi.board.version: 1.0 dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 31 dmi.chassis.vendor: ASUSTeK COMPUTER INC. dmi.chassis.version: 1.0 dmi.ec.firmware.release: 3.6 dmi.modalias: dmi:bvnAmericanMegatrendsInternational,LLC.:bvrHN7306EAC.307:bd01/27/2026:br5.36:efr3.6:svnASUS:pnProArtPX13HN7306EAC:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnHN7306EAC:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct31:cvr1.0:sku:pfaProArtPX13: dmi.product.family: ProArt PX13 dmi.product.name: ProArt PX13 HN7306EAC dmi.product.version: 1.0 dmi.sys.vendor: ASUS To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2163363/+subscriptions

[Bug 2158377] Re: ext4: writeback causes kernel oops when low on space

This bug is awaiting verification that the linux-azure- nvidia/6.8.0-1044.47 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-noble-linux-azure-nvidia' to 'verification-done-noble-linux-azure-nvidia'. If the problem still exists, change the tag 'verification-needed-noble-linux-azure-nvidia' to 'verification-failed-noble-linux-azure-nvidia'. 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! ** Tags added: kernel-spammed-noble-linux-azure-nvidia-v2 verification-needed-noble-linux-azure-nvidia -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2158377 Title: ext4: writeback causes kernel oops when low on space Status in linux package in Ubuntu: Invalid Status in linux source package in Noble: Fix Released Bug description: SRU Justification: [Impact] The noble upstream stable patchset 2026-05-28 (LP: #2154496) introduced refactoring patches targeting ext4 code, originating from upstream stable branch linux-6.6.y. During regression testing of the generic noble kernel, the ltp tests mmap14 and mmap16 were observed to fail, causing a kernel oops. Through bisecting, upstream commit f7d1331f16a8 ("ext4: get rid of ppath in ext4_ext_insert_extent()") was found to be cause. This commit was the first in the refactoring series of commits targeting ext4 in v6.6.130. The following stacktrace was recorded on an arm64 openstack instance: [ 1194.380996] Unable to handle kernel paging request at virtual address ffffffffffffffec [ 1194.381993] Mem abort info: [ 1194.382451] ESR = 0x0000000096000004 [ 1194.382950] EC = 0x25: DABT (current EL), IL = 32 bits [ 1194.383615] SET = 0, FnV = 0 [ 1194.384067] EA = 0, S1PTW = 0 [ 1194.384534] FSC = 0x04: level 0 translation fault [ 1194.385143] Data abort info: [ 1194.385626] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 1194.386310] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 1194.387026] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 1194.391322] swapper pgtable: 4k pages, 48-bit VAs, pgdp=00000000cc641000 [ 1194.393554] [ffffffffffffffec] pgd=0000000000000000, p4d=0000000000000000 [ 1194.394958] Internal error: Oops: 0000000096000004 [#1] SMP [ 1194.395660] Modules linked in: brd overlay exfat bcachefs lz4hc_compress lz4_compress xfs sctp ip6_udp_tunnel udp_tunnel nfsd auth_rpcgss nfs_acl lockd grace sunrpc tls qrtr cfg80211 binfmt_misc nls_iso8859_1 input_leds sch_fq_codel dm_multipath efi_pstore nfnetlink dmi_sysfs qemu_fw_cfg ip_tables x_tables autofs4 hid_generic usbhid hid btrfs blake2b_generic raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor xor_neon raid6_pq libcrc32c raid1 raid0 crct10dif_ce polyval_ce polyval_generic ghash_ce sm4 sha2_ce sha256_arm64 virtio_gpu arm_smccc_trng sha1_ce virtio_rng virtio_dma_buf xhci_pci xhci_pci_renesas aes_neon_bs aes_neon_blk aes_ce_blk aes_ce_cipher [last unloaded: init_module(OE)] [ 1194.405523] CPU: 1 PID: 95 Comm: kworker/u6:1 Tainted: G OE 6.8.0-132-generic #133-Ubuntu [ 1194.407319] Hardware name: QEMU KVM Virtual Machine, BIOS 2025.02-8~22.04.0~ppa3 05/14/2025 [ 1194.408502] Workqueue: writeback wb_workfn (flush-7:0) [ 1194.409343] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 1194.410263] pc : ext4_ext_map_blocks+0x2a0/0xa18 [ 1194.410979] lr : ext4_ext_map_blocks+0x8e8/0xa18 [ 1194.411685] sp : ffff8000803db600 [ 1194.412280] x29: ffff8000803db6a0 x28: 0000000000000ee8 x27: ffff0000c3641280 [ 1194.413248] x26: ffff0000cb20b000 x25: ffffffffffffffe4 x24: 000000000000042f [ 1194.414196] x23: ffff0000c286bc40 x22: ffff0000c36413a8 x21: ffff8000803db948 [ 1194.415141] x20: 0000000000000008 x19: 0000000000000000 x18: ffff800080381078 [ 1194.416131] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 [ 1194.417083] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 [ 1194.418051] x11: 0000000000000000 x10: 0000000000000000 x9 : ffffa6fb00b8227c [ 1194.419026] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 [ 1194.419949] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 [ 1194.420897] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 [ 1194.421851] Call trace: [ 1194.422404] ext4_ext_map_blocks+0x2a0/0xa18 [ 1194.423106] ext4_map_blocks+0x1c4/0x650 [ 1194.423755] mpage_map_one_extent+0x7c/0x1e0 [ 1194.424456] mpage_map_and_submit_extent+0x94/0x428 [ 1194.425196] ext4_do_writepages+0x6c0/0x7d8 [ 1194.425883] ext4_writepages+0x88/0x128 [ 1194.426570] do_writepages+0x98/0x210 [ 1194.427222] __writeback_single_inode+0x50/0x390 [ 1194.427947] writeback_sb_inodes+0x230/0x4d8 [ 1194.428666] wb_writeback+0x128/0x410 [ 1194.429324] wb_do_writeback+0xb4/0x398 [ 1194.429998] wb_workfn+0x80/0x258 [ 1194.430604] process_one_work+0x17c/0x448 [ 1194.431289] worker_thread+0x1bc/0x3a0 [ 1194.431923] kthread+0xf8/0x110 [ 1194.432533] ret_from_fork+0x10/0x20 [ 1194.433178] Code: b9003fe2 f94023f9 b9000ea0 b4001a39 (79401337) [ 1194.434077] ---[ end trace 0000000000000000 ]--- The crash is triggered during normal writeback when the filesystem is low on space. Any workload that writes to ext4 with unwritten (preallocated/fallocated) extents under space pressure can hit this. It is fatal to the affected writeback worker thread. [Explanation] The kernel crash (oops) occurs during ext4 writeback in `ext4_ext_map_blocks()` when the filesystem encounters an ENOSPC (no space left on device) condition while handling unwritten extents. The crash manifests as a page fault at address `0xffffffffffffffec` (which is `ERR_PTR(-ENOSPC) + 8`) on arm64, triggered from a writeback worker thread. The ext4 extent code underwent a significant refactoring series that changed how extent path objects are passed between functions. Previously, functions used double-pointer (`struct ext4_ext_path **ppath`) semantics — on error, the callee would set `*ppath = NULL`, ensuring the caller never held a dangling or invalid pointer. The refactoring changed these functions to return the path directly (or `ERR_PTR` on error). After this refactoring, functions like `ext4_ext_handle_unwritten_extents()` and `ext4_ext_insert_extent()` return `ERR_PTR(-ENOSPC)` on failure. The caller (`ext4_ext_map_blocks`) stores this error pointer in its local `path` variable and jumps to its cleanup label, where `ext4_free_ext_path(path)` is called. However, `ext4_free_ext_path()` was never updated to handle `ERR_PTR` values — it only had a NULL check. As a result, it attempts to dereference the error pointer (specifically reading `path->p_depth`), causing the kernel page fault. [Fix] Cherry-pick this missing prerequisite patch: 6b854d552711 ("ext4: get rid of ppath in get_ext_path()"). This patch adds `IS_ERR_OR_NULL()` guards to both `ext4_ext_drop_refs()` and `ext4_free_ext_path()`. This teaches these cleanup functions to gracefully handle error pointers by returning immediately, which is necessary now that the refactored call chain can leave `path` set to an `ERR_PTR` value when reaching cleanup code. [Test Plan] Run the ltp tests mmap14 and mmp16 that reliably trigger the crash. The tests should complete successfully without triggering a kernel crash. [Where problems could occur] If problems with this fix were to occur, they would manifest as silent memory leaks in ext4 extent handling - specifically, any code path that previously relied on `ext4_free_ext_path()` to actually free a valid path object but now mistakenly passes an `IS_ERR()` value would silently skip the free and leak the already-freed (or never-allocated) path, making such bugs harder to detect rather than causing a visible crash. Conversely, if any code path were to accidentally store an `ERR_PTR` in a path variable that is later reused (rather than cleaned up), the `IS_ERR_OR_NULL` guard would mask what should be a loud failure, potentially leading to subtle use-after-free or NULL-dereference bugs downstream when that variable is subsequently passed to `ext4_find_extent()` for recycling. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2158377/+subscriptions

[Bug 2163620] Re: [Ubuntu 26.10] : KVM guest boot hangs on POWER11 host when processor compatibility mode is set to POWER10

Thanks for reporting. The patchset has been sent to the our kernel team mailing list and will be applied to Stonking as soon as possible: https://lists.ubuntu.com/archives/kernel-team/2026-August/170985.html ** Also affects: linux (Ubuntu Stonking) Importance: Undecided Status: New ** Changed in: linux (Ubuntu Stonking) Status: New => In Progress -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2163620 Title: [Ubuntu 26.10] : KVM guest boot hangs on POWER11 host when processor compatibility mode is set to POWER10 Status in linux package in Ubuntu: In Progress Status in linux source package in Stonking: In Progress Bug description: [Impact] On a POWER11 system with the processor compatibility mode set to POWER10, Ubuntu 26.10 guest installation fails to boot on a KVM-enabled host. When a guest is created using virt-install and booted from the Ubuntu 26.10 installation ISO, the boot process hangs during early kernel initialization and the installer does not proceed further. [Fix] Apply the following patches from linux-next: - 884ea0283f4e KVM: PPC: Book3S HV: Validate arch_compat against host compatibility mode - ac3e65ddddf3 KVM: PPC: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl - b76fb087efcd KVM: PPC: Book3S HV: Implement compat CPU capability retrieval for KVM on PowerVM - 8735048f54ec KVM: PPC: Book3S HV: Add support for compat CPU capabilities for KVM on PowerNV - c1721e584244 KVM: PPC: Document KVM_PPC_GET_COMPAT_CAPS ioctl [Test Plan] - Setup KVM enabled host with Ubuntu26.10. - Install libvirt and qemu packages required for bringing up GUests - Create and boot an Ubuntu 26.10 KVM guest from the Ubuntu 26.10 installation ISO on a POWER11 LPAR running in POWER10 compatibility mode using the following command: ``` /usr/bin/virt-install --connect=qemu:///system --hvm --accelerate --name 'vm' --machine pseries --memory=10000 --vcpu=10,sockets=1,cores=10,threads=1 --import --nographics --os-variant ubuntu25.10 --serial pty --memballoon model=virtio --controller type=scsi,model=virtio-scsi --disk path=/home/ubuntu26_10.qcow2,bus=scsi,size=50,format=qcow2 --network=bridge=virbr0,model=virtio --boot emulator=/usr/bin/qemu-system-ppc64 --cdrom /home/ubuntu-26.10-snapshot2-live-server-ppc64el.iso ``` [Regression Potential] The change is confined to powerpc nested virtualization code. Users of nested virtualization in powerpc may be affected. --- == Problem Description === On a POWER11 system with the processor compatibility mode set to POWER10, Ubuntu 26.10 guest installation fails to boot on a KVM-enabled host. When a guest is created using virt-install and booted from the Ubuntu 26.10 installation ISO, the boot process hangs during early kernel initialization and the installer does not proceed further. HOST ENV: OS : Ubuntu 26.10 (Stonking Stingray) kernel : 7.0.0-14-generic libvirt : libvirtd (libvirt) 12.0.0 qemu : QEMU emulator version 10.2.1 on host : # lscpu Architecture: ppc64le   Byte Order: Little Endian CPU(s): 80   On-line CPU(s) list: 0-79 Model name: POWER10 (architected), altivec supported   Model: 2.0 (pvr 0082 0200)   Thread(s) per core: 8   Core(s) per socket: 10   Socket(s): 1 Virtualization features:   Hypervisor vendor: pHyp   Virtualization type: para Caches (sum of all):   L1d: 640 KiB (20 instances)   L1i: 960 KiB (20 instances)   L2: 20 MiB (20 instances)   L3: 80 MiB (20 instances) NUMA:   NUMA node(s): 3   NUMA node0 CPU(s):   NUMA node1 CPU(s): 0-79   NUMA node2 CPU(s): Vulnerabilities:   Gather data sampling: Not affected   Ghostwrite: Not affected   Indirect target selection: Not affected   Itlb multihit: Not affected   L1tf: Not affected   Mds: Not affected   Meltdown: Not affected   Mmio stale data: Not affected   Old microcode: Not affected   Reg file data sampling: Not affected   Retbleed: Not affected   Spec rstack overflow: Not affected   Spec store bypass: Not affected   Spectre v1: Mitigation; __user pointer sanitization, ori31 speculation barrier enabled   Spectre v2: Mitigation; Software count cache flush (hardware accelerated), Software link stack flush   Srbds: Not affected   Tsa: Not affected   Tsx async abort: Not affected   Vmscape: Not affected Steps to re-create: =================== - Setup KVM enabled host with Ubuntu26.10. - Install libvirt and qemu packages required for bringing up GUests - Create and boot an Ubuntu 26.10 KVM guest from the Ubuntu 26.10 installation ISO on a POWER11 LPAR running in POWER10 compatibility mode using the following command: --logs-- /usr/bin/virt-install --connect=qemu:///system --hvm --accelerate --name 'vm' --machine pseries --memory=10000 --vcpu=10,sockets=1,cores=10,threads=1 --import --nographics --os-variant ubuntu25.10 --serial pty --memballoon model=virtio --controller type=scsi,model=virtio-scsi --disk path=/home/ubuntu26_10.qcow2,bus=scsi,size=50,format=qcow2 --network=bridge=virbr0,model=virtio --boot emulator=/usr/bin/qemu-system-ppc64 --cdrom /home/ubuntu-26.10-snapshot2-live-server-ppc64el.iso WARNING CDROM media does not print to the text console by default, so you likely will not see text install output. You might want to use --location. See the man page for examples of using --location with CDROM media Starting install... Allocating 'ubuntu26_10.qcow2' | 50 GB 00:00:00 Creating domain... | 00:00:00 Running text console command: virsh --connect qemu:///system console vm Connected to domain 'vm' Escape character is ^] (Ctrl + ]) Populating /vdevice methods Populating /vdevice/vty@30000000 Populating /vdevice/nvram@71000000 Populating /pci@800000020000000                      00 0800 (D) : 1af4 1000 virtio [ net ]                      00 1000 (D) : 1af4 1004 virtio [ scsi ] Populating /pci@800000020000000/scsi@2        SCSI: Looking for devices           100000000000000 DISK : "QEMU QEMU HARDDISK 2.5+"           100000100000000 CD-ROM : "QEMU QEMU CD-ROM 2.5+"                      00 1800 (D) : 1b36 000d serial bus [ usb-xhci ]                      00 2000 (D) : 1af4 1003 virtio [ serial ]                      00 2800 (D) : 1af4 1002 legacy-device*                      00 3000 (D) : 1af4 1005 legacy-device* No NVRAM common partition, re-initializing... Scanning USB   XHCI: Initializing Using default console: /vdevice/vty@30000000   Welcome to Open Firmware   Copyright (c) 2004, 2017 IBM Corporation All rights reserved.   This program and the accompanying materials are made available   under the terms of the BSD License available at   http://www.opensource.org/licenses/bsd-license.php Trying to load: from: /pci@800000020000000/scsi@2/disk@100000100000000 ... Successfully loaded Welcome to GRUB! error: couldn't examine /ibm,secure-boot property. error: unrecognized number.                              GNU GRUB version 2.14  +----------------------------------------------------------------------------+  |*Try or Install Ubuntu Server |  | |  | |  | |  | |  | |  | |  | |  | |  | |  | |  | |  +----------------------------------------------------------------------------+       Use the ^ and v keys to select which entry is highlighted.       Press enter to boot the selected OS, `e' to edit the commands       before booting or `c' for a command-line. OF stdout device is: /vdevice/vty@30000000 Preparing to boot Linux version 7.0.0-14-generic (buildd@bos03-ppc64el-029) (powerpc64le-linux-gnu-gcc (Ubuntu 15.2.0-16ubuntu1) 15.2.0, GNU ld (GNU Binutils for Ubuntu) 2.46) #14-Ubuntu SMP PREEMPT_DYNAMIC Mon Apr 13 11:10:37 UTC 2026 (Ubuntu 7.0.0-14.14-generic 7.0.0) Detected machine type: 0000000000000101 command line: BOOT_IMAGE=/casper/vmlinux quiet --- Max number of cores passed to firmware: 2048 (NR_CPUS = 2048) Calling ibm,client-architecture-support... == Comment: #2 == The patches are in ppc next now: c1721e584244 KVM: PPC: Document KVM_PPC_GET_COMPAT_CAPS ioctl 8735048f54ec KVM: PPC: Book3S HV: Add support for compat CPU capabilities for KVM on PowerNV b76fb087efcd KVM: PPC: Book3S HV: Implement compat CPU capability retrieval for KVM on PowerVM ac3e65ddddf3 KVM: PPC: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl 884ea0283f4e KVM: PPC: Book3S HV: Validate arch_compat against host compatibility mode Please note that one of the dependent patches had already made it to upstream. e4de1b9cb3b5 ("powerpc/dt_cpu_ftrs: Set CPU_FTR_P11_PVR for Power11 and later processors") To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2163620/+subscriptions

[Bug 2163620] Re: [Ubuntu 26.10] : KVM guest boot hangs on POWER11 host when processor compatibility mode is set to POWER10

** Description changed: + [Impact] + + On a POWER11 system with the processor compatibility mode set to POWER10, + Ubuntu 26.10 guest installation fails to boot on a KVM-enabled host. + When a guest is created using virt-install and booted from the Ubuntu 26.10 installation ISO, + the boot process hangs during early kernel initialization and the installer does not proceed further. + + [Fix] + + Apply the following patches from linux-next: + - 884ea0283f4e KVM: PPC: Book3S HV: Validate arch_compat against host compatibility mode + - ac3e65ddddf3 KVM: PPC: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl + - b76fb087efcd KVM: PPC: Book3S HV: Implement compat CPU capability retrieval + for KVM on PowerVM + - 8735048f54ec KVM: PPC: Book3S HV: Add support for compat CPU capabilities for KVM on PowerNV + - c1721e584244 KVM: PPC: Document KVM_PPC_GET_COMPAT_CAPS ioctl + + [Test Plan] + + - Setup KVM enabled host with Ubuntu26.10. + - Install libvirt and qemu packages required for bringing up GUests + - Create and boot an Ubuntu 26.10 KVM guest from the Ubuntu 26.10 installation ISO on a POWER11 LPAR running in POWER10 compatibility mode using the following command: + ``` + /usr/bin/virt-install --connect=qemu:///system --hvm --accelerate --name 'vm' --machine pseries --memory=10000 --vcpu=10,sockets=1,cores=10,threads=1 --import --nographics --os-variant ubuntu25.10 --serial pty --memballoon model=virtio --controller type=scsi,model=virtio-scsi --disk path=/home/ubuntu26_10.qcow2,bus=scsi,size=50,format=qcow2 --network=bridge=virbr0,model=virtio --boot emulator=/usr/bin/qemu-system-ppc64 --cdrom /home/ubuntu-26.10-snapshot2-live-server-ppc64el.iso + ``` + + [Regression Potential] + + The change is confined to powerpc nested virtualization code. + Users of nested virtualization in powerpc may be affected. + + --- + == Problem Description === On a POWER11 system with the processor compatibility mode set to POWER10, Ubuntu 26.10 guest installation fails to boot on a KVM-enabled host. When a guest is created using virt-install and booted from the Ubuntu 26.10 installation ISO, the boot process hangs during early kernel initialization and the installer does not proceed further. HOST ENV: OS : Ubuntu 26.10 (Stonking Stingray) kernel : 7.0.0-14-generic libvirt : libvirtd (libvirt) 12.0.0 qemu : QEMU emulator version 10.2.1 on host : # lscpu Architecture: ppc64le - Byte Order: Little Endian +   Byte Order: Little Endian CPU(s): 80 - On-line CPU(s) list: 0-79 +   On-line CPU(s) list: 0-79 Model name: POWER10 (architected), altivec supported - Model: 2.0 (pvr 0082 0200) - Thread(s) per core: 8 - Core(s) per socket: 10 - Socket(s): 1 +   Model: 2.0 (pvr 0082 0200) +   Thread(s) per core: 8 +   Core(s) per socket: 10 +   Socket(s): 1 Virtualization features: - Hypervisor vendor: pHyp - Virtualization type: para +   Hypervisor vendor: pHyp +   Virtualization type: para Caches (sum of all): - L1d: 640 KiB (20 instances) - L1i: 960 KiB (20 instances) - L2: 20 MiB (20 instances) - L3: 80 MiB (20 instances) +   L1d: 640 KiB (20 instances) +   L1i: 960 KiB (20 instances) +   L2: 20 MiB (20 instances) +   L3: 80 MiB (20 instances) NUMA: - NUMA node(s): 3 - NUMA node0 CPU(s): - NUMA node1 CPU(s): 0-79 - NUMA node2 CPU(s): +   NUMA node(s): 3 +   NUMA node0 CPU(s): +   NUMA node1 CPU(s): 0-79 +   NUMA node2 CPU(s): Vulnerabilities: - Gather data sampling: Not affected - Ghostwrite: Not affected - Indirect target selection: Not affected - Itlb multihit: Not affected - L1tf: Not affected - Mds: Not affected - Meltdown: Not affected - Mmio stale data: Not affected - Old microcode: Not affected - Reg file data sampling: Not affected - Retbleed: Not affected - Spec rstack overflow: Not affected - Spec store bypass: Not affected - Spectre v1: Mitigation; __user pointer sanitization, ori31 speculation barrier enabled - Spectre v2: Mitigation; Software count cache flush (hardware accelerated), Software link stack flush - Srbds: Not affected - Tsa: Not affected - Tsx async abort: Not affected - Vmscape: Not affected +   Gather data sampling: Not affected +   Ghostwrite: Not affected +   Indirect target selection: Not affected +   Itlb multihit: Not affected +   L1tf: Not affected +   Mds: Not affected +   Meltdown: Not affected +   Mmio stale data: Not affected +   Old microcode: Not affected +   Reg file data sampling: Not affected +   Retbleed: Not affected +   Spec rstack overflow: Not affected +   Spec store bypass: Not affected +   Spectre v1: Mitigation; __user pointer sanitization, ori31 speculation barrier enabled +   Spectre v2: Mitigation; Software count cache flush (hardware accelerated), Software link stack flush +   Srbds: Not affected +   Tsa: Not affected +   Tsx async abort: Not affected +   Vmscape: Not affected Steps to re-create: =================== - Setup KVM enabled host with Ubuntu26.10. - Install libvirt and qemu packages required for bringing up GUests - Create and boot an Ubuntu 26.10 KVM guest from the Ubuntu 26.10 installation ISO on a POWER11 LPAR running in POWER10 compatibility mode using the following command: --logs-- /usr/bin/virt-install --connect=qemu:///system --hvm --accelerate --name 'vm' --machine pseries --memory=10000 --vcpu=10,sockets=1,cores=10,threads=1 --import --nographics --os-variant ubuntu25.10 --serial pty --memballoon model=virtio --controller type=scsi,model=virtio-scsi --disk path=/home/ubuntu26_10.qcow2,bus=scsi,size=50,format=qcow2 --network=bridge=virbr0,model=virtio --boot emulator=/usr/bin/qemu-system-ppc64 --cdrom /home/ubuntu-26.10-snapshot2-live-server-ppc64el.iso WARNING CDROM media does not print to the text console by default, so you likely will not see text install output. You might want to use --location. See the man page for examples of using --location with CDROM media Starting install... Allocating 'ubuntu26_10.qcow2' | 50 GB 00:00:00 Creating domain... | 00:00:00 Running text console command: virsh --connect qemu:///system console vm Connected to domain 'vm' Escape character is ^] (Ctrl + ]) Populating /vdevice methods Populating /vdevice/vty@30000000 Populating /vdevice/nvram@71000000 Populating /pci@800000020000000 - 00 0800 (D) : 1af4 1000 virtio [ net ] - 00 1000 (D) : 1af4 1004 virtio [ scsi ] +                      00 0800 (D) : 1af4 1000 virtio [ net ] +                      00 1000 (D) : 1af4 1004 virtio [ scsi ] Populating /pci@800000020000000/scsi@2 - SCSI: Looking for devices - 100000000000000 DISK : "QEMU QEMU HARDDISK 2.5+" - 100000100000000 CD-ROM : "QEMU QEMU CD-ROM 2.5+" - 00 1800 (D) : 1b36 000d serial bus [ usb-xhci ] - 00 2000 (D) : 1af4 1003 virtio [ serial ] - 00 2800 (D) : 1af4 1002 legacy-device* - 00 3000 (D) : 1af4 1005 legacy-device* +        SCSI: Looking for devices +           100000000000000 DISK : "QEMU QEMU HARDDISK 2.5+" +           100000100000000 CD-ROM : "QEMU QEMU CD-ROM 2.5+" +                      00 1800 (D) : 1b36 000d serial bus [ usb-xhci ] +                      00 2000 (D) : 1af4 1003 virtio [ serial ] +                      00 2800 (D) : 1af4 1002 legacy-device* +                      00 3000 (D) : 1af4 1005 legacy-device* No NVRAM common partition, re-initializing... Scanning USB - XHCI: Initializing +   XHCI: Initializing Using default console: /vdevice/vty@30000000 - Welcome to Open Firmware +   Welcome to Open Firmware - Copyright (c) 2004, 2017 IBM Corporation All rights reserved. - This program and the accompanying materials are made available - under the terms of the BSD License available at - http://www.opensource.org/licenses/bsd-license.php - +   Copyright (c) 2004, 2017 IBM Corporation All rights reserved. +   This program and the accompanying materials are made available +   under the terms of the BSD License available at +   http://www.opensource.org/licenses/bsd-license.php Trying to load: from: /pci@800000020000000/scsi@2/disk@100000100000000 ... Successfully loaded Welcome to GRUB! error: couldn't examine /ibm,secure-boot property. error: unrecognized number. - GNU GRUB version 2.14 +                              GNU GRUB version 2.14 - +----------------------------------------------------------------------------+ - |*Try or Install Ubuntu Server | - | | - | | - | | - | | - | | - | | - | | - | | - | | - | | - | | - +----------------------------------------------------------------------------+ +  +----------------------------------------------------------------------------+ +  |*Try or Install Ubuntu Server | +  | | +  | | +  | | +  | | +  | | +  | | +  | | +  | | +  | | +  | | +  | | +  +----------------------------------------------------------------------------+ - Use the ^ and v keys to select which entry is highlighted. - Press enter to boot the selected OS, `e' to edit the commands - before booting or `c' for a command-line. +       Use the ^ and v keys to select which entry is highlighted. +       Press enter to boot the selected OS, `e' to edit the commands +       before booting or `c' for a command-line. OF stdout device is: /vdevice/vty@30000000 Preparing to boot Linux version 7.0.0-14-generic (buildd@bos03-ppc64el-029) (powerpc64le-linux-gnu-gcc (Ubuntu 15.2.0-16ubuntu1) 15.2.0, GNU ld (GNU Binutils for Ubuntu) 2.46) #14-Ubuntu SMP PREEMPT_DYNAMIC Mon Apr 13 11:10:37 UTC 2026 (Ubuntu 7.0.0-14.14-generic 7.0.0) Detected machine type: 0000000000000101 command line: BOOT_IMAGE=/casper/vmlinux quiet --- Max number of cores passed to firmware: 2048 (NR_CPUS = 2048) Calling ibm,client-architecture-support... - == Comment: #2 == The patches are in ppc next now: c1721e584244 KVM: PPC: Document KVM_PPC_GET_COMPAT_CAPS ioctl 8735048f54ec KVM: PPC: Book3S HV: Add support for compat CPU capabilities for KVM on PowerNV b76fb087efcd KVM: PPC: Book3S HV: Implement compat CPU capability retrieval for KVM on PowerVM ac3e65ddddf3 KVM: PPC: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl 884ea0283f4e KVM: PPC: Book3S HV: Validate arch_compat against host compatibility mode Please note that one of the dependent patches had already made it to upstream. e4de1b9cb3b5 ("powerpc/dt_cpu_ftrs: Set CPU_FTR_P11_PVR for Power11 and later processors") ** Also affects: linux (Ubuntu) Importance: Undecided Status: New ** No longer affects: kernel-package (Ubuntu) -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2163620 Title: [Ubuntu 26.10] : KVM guest boot hangs on POWER11 host when processor compatibility mode is set to POWER10 Status in linux package in Ubuntu: New Bug description: [Impact] On a POWER11 system with the processor compatibility mode set to POWER10, Ubuntu 26.10 guest installation fails to boot on a KVM-enabled host. When a guest is created using virt-install and booted from the Ubuntu 26.10 installation ISO, the boot process hangs during early kernel initialization and the installer does not proceed further. [Fix] Apply the following patches from linux-next: - 884ea0283f4e KVM: PPC: Book3S HV: Validate arch_compat against host compatibility mode - ac3e65ddddf3 KVM: PPC: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl - b76fb087efcd KVM: PPC: Book3S HV: Implement compat CPU capability retrieval for KVM on PowerVM - 8735048f54ec KVM: PPC: Book3S HV: Add support for compat CPU capabilities for KVM on PowerNV - c1721e584244 KVM: PPC: Document KVM_PPC_GET_COMPAT_CAPS ioctl [Test Plan] - Setup KVM enabled host with Ubuntu26.10. - Install libvirt and qemu packages required for bringing up GUests - Create and boot an Ubuntu 26.10 KVM guest from the Ubuntu 26.10 installation ISO on a POWER11 LPAR running in POWER10 compatibility mode using the following command: ``` /usr/bin/virt-install --connect=qemu:///system --hvm --accelerate --name 'vm' --machine pseries --memory=10000 --vcpu=10,sockets=1,cores=10,threads=1 --import --nographics --os-variant ubuntu25.10 --serial pty --memballoon model=virtio --controller type=scsi,model=virtio-scsi --disk path=/home/ubuntu26_10.qcow2,bus=scsi,size=50,format=qcow2 --network=bridge=virbr0,model=virtio --boot emulator=/usr/bin/qemu-system-ppc64 --cdrom /home/ubuntu-26.10-snapshot2-live-server-ppc64el.iso ``` [Regression Potential] The change is confined to powerpc nested virtualization code. Users of nested virtualization in powerpc may be affected. --- == Problem Description === On a POWER11 system with the processor compatibility mode set to POWER10, Ubuntu 26.10 guest installation fails to boot on a KVM-enabled host. When a guest is created using virt-install and booted from the Ubuntu 26.10 installation ISO, the boot process hangs during early kernel initialization and the installer does not proceed further. HOST ENV: OS : Ubuntu 26.10 (Stonking Stingray) kernel : 7.0.0-14-generic libvirt : libvirtd (libvirt) 12.0.0 qemu : QEMU emulator version 10.2.1 on host : # lscpu Architecture: ppc64le   Byte Order: Little Endian CPU(s): 80   On-line CPU(s) list: 0-79 Model name: POWER10 (architected), altivec supported   Model: 2.0 (pvr 0082 0200)   Thread(s) per core: 8   Core(s) per socket: 10   Socket(s): 1 Virtualization features:   Hypervisor vendor: pHyp   Virtualization type: para Caches (sum of all):   L1d: 640 KiB (20 instances)   L1i: 960 KiB (20 instances)   L2: 20 MiB (20 instances)   L3: 80 MiB (20 instances) NUMA:   NUMA node(s): 3   NUMA node0 CPU(s):   NUMA node1 CPU(s): 0-79   NUMA node2 CPU(s): Vulnerabilities:   Gather data sampling: Not affected   Ghostwrite: Not affected   Indirect target selection: Not affected   Itlb multihit: Not affected   L1tf: Not affected   Mds: Not affected   Meltdown: Not affected   Mmio stale data: Not affected   Old microcode: Not affected   Reg file data sampling: Not affected   Retbleed: Not affected   Spec rstack overflow: Not affected   Spec store bypass: Not affected   Spectre v1: Mitigation; __user pointer sanitization, ori31 speculation barrier enabled   Spectre v2: Mitigation; Software count cache flush (hardware accelerated), Software link stack flush   Srbds: Not affected   Tsa: Not affected   Tsx async abort: Not affected   Vmscape: Not affected Steps to re-create: =================== - Setup KVM enabled host with Ubuntu26.10. - Install libvirt and qemu packages required for bringing up GUests - Create and boot an Ubuntu 26.10 KVM guest from the Ubuntu 26.10 installation ISO on a POWER11 LPAR running in POWER10 compatibility mode using the following command: --logs-- /usr/bin/virt-install --connect=qemu:///system --hvm --accelerate --name 'vm' --machine pseries --memory=10000 --vcpu=10,sockets=1,cores=10,threads=1 --import --nographics --os-variant ubuntu25.10 --serial pty --memballoon model=virtio --controller type=scsi,model=virtio-scsi --disk path=/home/ubuntu26_10.qcow2,bus=scsi,size=50,format=qcow2 --network=bridge=virbr0,model=virtio --boot emulator=/usr/bin/qemu-system-ppc64 --cdrom /home/ubuntu-26.10-snapshot2-live-server-ppc64el.iso WARNING CDROM media does not print to the text console by default, so you likely will not see text install output. You might want to use --location. See the man page for examples of using --location with CDROM media Starting install... Allocating 'ubuntu26_10.qcow2' | 50 GB 00:00:00 Creating domain... | 00:00:00 Running text console command: virsh --connect qemu:///system console vm Connected to domain 'vm' Escape character is ^] (Ctrl + ]) Populating /vdevice methods Populating /vdevice/vty@30000000 Populating /vdevice/nvram@71000000 Populating /pci@800000020000000                      00 0800 (D) : 1af4 1000 virtio [ net ]                      00 1000 (D) : 1af4 1004 virtio [ scsi ] Populating /pci@800000020000000/scsi@2        SCSI: Looking for devices           100000000000000 DISK : "QEMU QEMU HARDDISK 2.5+"           100000100000000 CD-ROM : "QEMU QEMU CD-ROM 2.5+"                      00 1800 (D) : 1b36 000d serial bus [ usb-xhci ]                      00 2000 (D) : 1af4 1003 virtio [ serial ]                      00 2800 (D) : 1af4 1002 legacy-device*                      00 3000 (D) : 1af4 1005 legacy-device* No NVRAM common partition, re-initializing... Scanning USB   XHCI: Initializing Using default console: /vdevice/vty@30000000   Welcome to Open Firmware   Copyright (c) 2004, 2017 IBM Corporation All rights reserved.   This program and the accompanying materials are made available   under the terms of the BSD License available at   http://www.opensource.org/licenses/bsd-license.php Trying to load: from: /pci@800000020000000/scsi@2/disk@100000100000000 ... Successfully loaded Welcome to GRUB! error: couldn't examine /ibm,secure-boot property. error: unrecognized number.                              GNU GRUB version 2.14  +----------------------------------------------------------------------------+  |*Try or Install Ubuntu Server |  | |  | |  | |  | |  | |  | |  | |  | |  | |  | |  | |  +----------------------------------------------------------------------------+       Use the ^ and v keys to select which entry is highlighted.       Press enter to boot the selected OS, `e' to edit the commands       before booting or `c' for a command-line. OF stdout device is: /vdevice/vty@30000000 Preparing to boot Linux version 7.0.0-14-generic (buildd@bos03-ppc64el-029) (powerpc64le-linux-gnu-gcc (Ubuntu 15.2.0-16ubuntu1) 15.2.0, GNU ld (GNU Binutils for Ubuntu) 2.46) #14-Ubuntu SMP PREEMPT_DYNAMIC Mon Apr 13 11:10:37 UTC 2026 (Ubuntu 7.0.0-14.14-generic 7.0.0) Detected machine type: 0000000000000101 command line: BOOT_IMAGE=/casper/vmlinux quiet --- Max number of cores passed to firmware: 2048 (NR_CPUS = 2048) Calling ibm,client-architecture-support... == Comment: #2 == The patches are in ppc next now: c1721e584244 KVM: PPC: Document KVM_PPC_GET_COMPAT_CAPS ioctl 8735048f54ec KVM: PPC: Book3S HV: Add support for compat CPU capabilities for KVM on PowerNV b76fb087efcd KVM: PPC: Book3S HV: Implement compat CPU capability retrieval for KVM on PowerVM ac3e65ddddf3 KVM: PPC: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl 884ea0283f4e KVM: PPC: Book3S HV: Validate arch_compat against host compatibility mode Please note that one of the dependent patches had already made it to upstream. e4de1b9cb3b5 ("powerpc/dt_cpu_ftrs: Set CPU_FTR_P11_PVR for Power11 and later processors") To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2163620/+subscriptions

[Bug 2164203] [NEW] iwlwifi regression causing iwlwifi to not load and severe IOMMU page faults and system stuttering during heavy traffic on Intel Wireless-AC 9560

Public bug reported: After upgrading to kernel version 7.0.0-30-generic,the wifi dissapears from my system and after manually loading iwlwifi system experiences severe micro-stutters and high CPU usage from systemd-journald during high-speed Wi-Fi downloads and speed tests. Looking at dmesg, the iwlwifi driver triggers thousands of recurring warnings:WARNING: drivers/iommu/dma-iommu.c:... iommu_dma_unmap_physiwl_pcie_irq_handler Hardware: Intel Corporation Cannon Lake PCH CNVi WiFi [8086:a370] (Wireless-AC 9560) Workaround used: Adding iommu=pt to GRUB_CMDLINE_LINUX_DEFAULT completely resolves the stutters, clears the dmesg errors, and stabilizes systemd-journald CPU usage. This indicates a regression in how the 7.0 kernel handles IOMMU DMA mapping/unmapping for this specific network module. Ubuntu 26.04 Lts ProblemType: Bug DistroRelease: Ubuntu 26.04 Package: linux-image-7.0.0-30-generic 7.0.0-30.30 ProcVersionSignature: Ubuntu 7.0.0-30.30-generic 7.0.12 Uname: Linux 7.0.0-30-generic x86_64 ApportVersion: 2.34.1-0ubuntu0.1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: ayan 1770 F.... wireplumber /dev/snd/controlC0: ayan 1770 F.... wireplumber /dev/snd/seq: ayan 1742 F.... pipewire CasperMD5CheckResult: pass CurrentDesktop: ubuntu:GNOME Date: Wed Aug 19 00:03:25 2026 InstallationDate: Installed on 2026-06-27 (52 days ago) InstallationMedia: Ubuntu 26.04 "Resolute Raccoon" - Release amd64 (20260423.1) MachineType: Micro-Star International Co., Ltd. GF65 Thin 9SD ProcEnviron: LANG=en_US.UTF-8 PATH=(custom, no user) SHELL=/usr/bin/zsh TERM=xterm-256color XDG_RUNTIME_DIR=<set> ProcFB: 0 nvidia-drmdrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-7.0.0-30-generic root=UUID=866c92aa-993c-4776-890e-5150d08f4aba ro quiet splash iommu=pt crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 10/21/2021 dmi.bios.release: 1.12 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: E16W1IMS.10C dmi.board.asset.tag: Default string dmi.board.name: MS-16W1 dmi.board.vendor: Micro-Star International Co., Ltd. dmi.board.version: REV:1.0 dmi.chassis.asset.tag: Default string dmi.chassis.type: 10 dmi.chassis.vendor: Micro-Star International Co., Ltd. dmi.chassis.version: Default string dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrE16W1IMS.10C:bd10/21/2021:br1.12:svnMicro-StarInternationalCo.,Ltd.:pnGF65Thin9SD:pvrREV1.0:rvnMicro-StarInternationalCo.,Ltd.:rnMS-16W1:rvrREV1.0:cvnMicro-StarInternationalCo.,Ltd.:ct10:cvrDefaultstring:sku16W1.1:pfaGF: dmi.product.family: GF dmi.product.name: GF65 Thin 9SD dmi.product.sku: 16W1.1 dmi.product.version: REV:1.0 dmi.sys.vendor: Micro-Star International Co., Ltd. ** Affects: linux (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug resolute wayland-session ** Attachment added: "lspci-vnvn.log" https://bugs.launchpad.net/bugs/2164203/+attachment/5993232/+files/lspci-vnvn.log -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2164203 Title: iwlwifi regression causing iwlwifi to not load and severe IOMMU page faults and system stuttering during heavy traffic on Intel Wireless-AC 9560 Status in linux package in Ubuntu: New Bug description: After upgrading to kernel version 7.0.0-30-generic,the wifi dissapears from my system and after manually loading iwlwifi system experiences severe micro-stutters and high CPU usage from systemd-journald during high-speed Wi-Fi downloads and speed tests. Looking at dmesg, the iwlwifi driver triggers thousands of recurring warnings:WARNING: drivers/iommu/dma-iommu.c:... iommu_dma_unmap_physiwl_pcie_irq_handler Hardware: Intel Corporation Cannon Lake PCH CNVi WiFi [8086:a370] (Wireless-AC 9560) Workaround used: Adding iommu=pt to GRUB_CMDLINE_LINUX_DEFAULT completely resolves the stutters, clears the dmesg errors, and stabilizes systemd-journald CPU usage. This indicates a regression in how the 7.0 kernel handles IOMMU DMA mapping/unmapping for this specific network module. Ubuntu 26.04 Lts ProblemType: Bug DistroRelease: Ubuntu 26.04 Package: linux-image-7.0.0-30-generic 7.0.0-30.30 ProcVersionSignature: Ubuntu 7.0.0-30.30-generic 7.0.12 Uname: Linux 7.0.0-30-generic x86_64 ApportVersion: 2.34.1-0ubuntu0.1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: ayan 1770 F.... wireplumber /dev/snd/controlC0: ayan 1770 F.... wireplumber /dev/snd/seq: ayan 1742 F.... pipewire CasperMD5CheckResult: pass CurrentDesktop: ubuntu:GNOME Date: Wed Aug 19 00:03:25 2026 InstallationDate: Installed on 2026-06-27 (52 days ago) InstallationMedia: Ubuntu 26.04 "Resolute Raccoon" - Release amd64 (20260423.1) MachineType: Micro-Star International Co., Ltd. GF65 Thin 9SD ProcEnviron: LANG=en_US.UTF-8 PATH=(custom, no user) SHELL=/usr/bin/zsh TERM=xterm-256color XDG_RUNTIME_DIR=<set> ProcFB: 0 nvidia-drmdrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-7.0.0-30-generic root=UUID=866c92aa-993c-4776-890e-5150d08f4aba ro quiet splash iommu=pt crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 10/21/2021 dmi.bios.release: 1.12 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: E16W1IMS.10C dmi.board.asset.tag: Default string dmi.board.name: MS-16W1 dmi.board.vendor: Micro-Star International Co., Ltd. dmi.board.version: REV:1.0 dmi.chassis.asset.tag: Default string dmi.chassis.type: 10 dmi.chassis.vendor: Micro-Star International Co., Ltd. dmi.chassis.version: Default string dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrE16W1IMS.10C:bd10/21/2021:br1.12:svnMicro-StarInternationalCo.,Ltd.:pnGF65Thin9SD:pvrREV1.0:rvnMicro-StarInternationalCo.,Ltd.:rnMS-16W1:rvrREV1.0:cvnMicro-StarInternationalCo.,Ltd.:ct10:cvrDefaultstring:sku16W1.1:pfaGF: dmi.product.family: GF dmi.product.name: GF65 Thin 9SD dmi.product.sku: 16W1.1 dmi.product.version: REV:1.0 dmi.sys.vendor: Micro-Star International Co., Ltd. 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[Bug 2156312] Re: Internal display black screen on Intel Lunar Lake with eDP panel

This bug is awaiting verification that the linux- realtime-7.0/7.0.0-31.31.1~24.04.1 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-noble-linux- realtime-7.0' to 'verification-done-noble-linux-realtime-7.0'. If the problem still exists, change the tag 'verification-needed-noble-linux- realtime-7.0' to 'verification-failed-noble-linux-realtime-7.0'. 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! ** Tags added: kernel-spammed-noble-linux-realtime-7.0-v2 verification-needed-noble-linux-realtime-7.0 -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2156312 Title: Internal display black screen on Intel Lunar Lake with eDP panel Status in HWE Next: New Status in linux package in Ubuntu: Invalid Status in linux-oem-6.17 package in Ubuntu: Invalid Status in linux source package in Noble: Invalid Status in linux-oem-6.17 source package in Noble: Fix Released Status in linux source package in Questing: Fix Released Status in linux-oem-6.17 source package in Questing: Invalid Status in linux source package in Resolute: Fix Released Status in linux-oem-6.17 source package in Resolute: Invalid Bug description: [Impact] Internal display goes black after login on Intel Lunar Lake systems with an eDP panel. The external monitor works. The internal display shows as disabled in display settings and cannot be enabled. Hits 100% on affected hardware (3 units, 15/15 attempts). The bug is caused by LOBF (Link Off Between Frames) being enabled on platforms that use the legacy VRR timing generator. Those platforms do not meet the bspec requirement for LOBF (Always-on VRR TG with fixed refresh rate mode). Enabling LOBF incorrectly causes the display to go dark. [Fix] Replace the raw vmin/vmax/flipline comparison with the proper bspec checks: - intel_vrr_always_use_vrr_tg() to gate LOBF on platforms with Always-on VRR TG - intel_vrr_is_fixed_rr() to confirm fixed refresh rate mode Backported from upstream commit 8a517b1e6d8b, merged in v7.1-rc1. [Test Plan] Boot on affected Intel Lunar Lake hardware with an eDP panel. Without patch: internal display is black after login; shows as disabled in display settings. With patch: internal display works normally after login. [Where problems could occur] Could affect intel_alpm.c LOBF configuration logic in the i915 driver. If intel_vrr_always_use_vrr_tg() or intel_vrr_is_fixed_rr() return wrong results on a platform, LOBF would be incorrectly blocked, and Panel Replay power savings would be lost on those machines. The display would still work — it would just not enter LOBF mode. To manage notifications about this bug go to: https://bugs.launchpad.net/hwe-next/+bug/2156312/+subscriptions

[Bug 2156556] Re: Fix no audio from right built-in speaker on HP ZBook with TAS2781 amplifier

This bug is awaiting verification that the linux- realtime-7.0/7.0.0-31.31.1~24.04.1 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-noble-linux- realtime-7.0' to 'verification-done-noble-linux-realtime-7.0'. If the problem still exists, change the tag 'verification-needed-noble-linux- realtime-7.0' to 'verification-failed-noble-linux-realtime-7.0'. 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! ** Tags added: kernel-spammed-noble-linux-realtime-7.0-v2 verification-needed-noble-linux-realtime-7.0 -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2156556 Title: Fix no audio from right built-in speaker on HP ZBook with TAS2781 amplifier Status in HWE Next: New Status in linux package in Ubuntu: New Status in linux-oem-6.17 package in Ubuntu: New Status in linux source package in Noble: New Status in linux-oem-6.17 source package in Noble: Fix Released Status in linux source package in Resolute: Fix Released Status in linux-oem-6.17 source package in Resolute: New Bug description: [Impact] The TI TAS2781 smart amp fails to initialize when connected over SPI on the new HP HP ZBook. The right built-in speaker will fail to output after reboot [Fix] Two changes in one commit: 1. Always run the software reset sequence for the amp, not just in the no-gpio path. This resets device-0 even when its hardware reset pin has no effect. 2. Ignore -EXDEV during block processing when the device is on SPI. The driver keeps iterating through the blocks and adds up the total block size correctly. Upstream commit (in tiwai/sound for-next, not yet in a released tag): 513480da5e9c ALSA: hda/tas2781: Fix device-0 reset issue and handle -EXDEV in block data processing https://patch.msgid.link/20260609105253.19510-1-baojun.xu@ti.com [Test Plan] On HP Zbook with a TAS2781 amp connected over SPI: $ dmesg | grep -i tas2781 Play audio: $ speaker-test -c 2 -t wav Without patch: dmesg shows "dev sw-reset fail" or "process_block: single write error" / "bulk_write error". No sound from the TAS2781 speakers. With patch: no reset or block errors in dmesg. Speakers play sound. [Where problems could occur] The reset change now runs the software reset on every path, including the gpio reset path. If the software reset is wrong for some amp, the device could fail to come up and stay silent. Both changes are amp init only, so a regression would show up as no sound on TAS2781 SPI systems. To manage notifications about this bug go to: https://bugs.launchpad.net/hwe-next/+bug/2156556/+subscriptions

[Bug 2158229] Re: MT7925 wifi is hard blocked on Dell's machine

This bug is awaiting verification that the linux-nvidia- bos/7.0.0-2018.18 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-resolute-linux-nvidia-bos' to 'verification-done-resolute-linux-nvidia-bos'. If the problem still exists, change the tag 'verification-needed-resolute-linux-nvidia-bos' to 'verification-failed-resolute-linux-nvidia-bos'. 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! ** Tags added: kernel-spammed-resolute-linux-nvidia-bos-v2 verification-needed-resolute-linux-nvidia-bos -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2158229 Title: MT7925 wifi is hard blocked on Dell's machine Status in linux package in Ubuntu: New Status in linux-hwe-7.0 package in Ubuntu: Invalid Status in linux-oem-6.17 package in Ubuntu: Invalid Status in linux source package in Noble: Invalid Status in linux-hwe-7.0 source package in Noble: Fix Released Status in linux-oem-6.17 source package in Noble: Fix Released Status in linux source package in Questing: Won't Fix Status in linux-hwe-7.0 source package in Questing: Invalid Status in linux-oem-6.17 source package in Questing: Invalid Status in linux source package in Resolute: In Progress Status in linux-hwe-7.0 source package in Resolute: Invalid Status in linux-oem-6.17 source package in Resolute: Invalid Status in linux source package in Stonking: New Status in linux-hwe-7.0 source package in Stonking: Invalid Status in linux-oem-6.17 source package in Stonking: Invalid Bug description: [Impact] The Wi-Fi is hard blocked on Dell systems (CIDs: 202505-36757, 202501-36195, 202501-36253) and HP systems with Mediatek MT7925 cards. The wireless connection cannot be used. The rfkill state shows: $ rfkill list 0: hci0: Bluetooth Soft blocked: no Hard blocked: no 1: phy0: Wireless LAN Soft blocked: no Hard blocked: yes [Fix] We revert the hardware rfkill polling feature for Mediatek MT7925 cards. This polling feature was introduced upstream in v6.16. We also revert the local DMI quirk for HP systems since polling is now disabled. Reverted commits: • Revert "wifi: mt76: mt7925: add rfkill_poll for hardware rfkill" (reverts upstream commit e54b870212c079bef4ff61238f8c1278a14d1863 from v6.16) • Revert local DMI quirk commit for HP systems (reverts local commit 20c9b07dcea9d49c876c9532a48a6dc88f43d0f9) [Test Plan] Check the rfkill state on affected hardware: $ rfkill list Without the patches: The Wireless LAN interface shows "Hard blocked: yes". The Wi-Fi connection does not work. With the patches: The Wireless LAN interface shows "Hard blocked: no". The Wi-Fi connection works. [Where problems could occur] This change affects the mt76 Mediatek wireless driver. If a system has a physical wireless switch that needs software polling, the switch will stop working. Toggling the physical switch would not change the Wi-Fi block state. ========================================================= [Impact] The wifi is hard blocked and can't be used randomly. [Test] 1. Boot up Machine 2. Run `rfkill list` to check wlan0 block state Wireless: Mediatek Inc. - 14c3:7925 ubuntu@localhost:~$ rfkill list 0: hci0: Bluetooth  Soft blocked: no  Hard blocked: no 1: phy0: Wireless LAN  Soft blocked: no  Hard blocked: yes [Affected Machines] 202505-36757 202501-36195 202501-36253 [Similar Issue] https://bugs.launchpad.net/ubuntu/+source/linux-oem-6.14/+bug/2127044 ProblemType: Bug DistroRelease: Ubuntu 24.04 Package: linux-image-6.17.0-1020-oem 6.17.0-1020.20 ProcVersionSignature: Ubuntu 6.17.0-1020.20-oem 6.17.13 Uname: Linux 6.17.0-1020-oem x86_64 ApportVersion: 2.28.2-0ubuntu0.1 Architecture: amd64 AudioDevicesInUse:  USER PID ACCESS COMMAND  /dev/snd/controlC1: ubuntu 1918 F.... pipewire                       ubuntu 1922 F.... wireplumber  /dev/snd/controlC0: ubuntu 1922 F.... wireplumber  /dev/snd/seq: ubuntu 1918 F.... pipewire CasperMD5CheckMismatches: ./casper/initrd ./casper/vmlinuz ./casper/minimal.standard.live.hotfix.manifest ./casper/minimal.standard.live.hotfix.size ./casper/minimal.standard.live.size ./casper/minimal.manifest ./casper/minimal.standard.manifest ./casper/minimal.standard.size ./casper/minimal.hotfix.size ./casper/minimal.standard.live.hotfix.squashfs ./casper/minimal.standard.hotfix.squashfs ./casper/minimal.standard.hotfix.size ./casper/minimal.hotfix.squashfs ./casper/minimal.standard.live.manifest ./casper/minimal.size ./boot/grub/grub.cfg CasperMD5CheckResult: fail Date: Thu Jun 25 05:43:16 2026 DistributionChannelDescriptor:  # This is the distribution channel descriptor for Ubuntu 24.04 for Dell  # For more information see http://wiki.ubuntu.com/DistributionChannelDescriptor  canonical-oem-somerville-noble-oem-24.04b-proposed-20250604-520 InstallationDate: Installed on 2026-05-07 (49 days ago) InstallationMedia: Ubuntu OEM 24.04.2 LTS "Noble Numbat" - Release amd64 (20250603) IwConfig:  lo no wireless extensions.  enp195s0f0 no wireless extensions.  wlp194s0 no wireless extensions. MachineType: Dell Inc. Dell Pro Max 14 MC14255 ProcFB: 0 amdgpudrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-6.17.0-1020-oem root=UUID=881d0e73-6adc-444d-90b2-9491672e82b1 ro quiet splash vt.handoff=7 RelatedPackageVersions:  linux-restricted-modules-6.17.0-1020-oem N/A  linux-backports-modules-6.17.0-1020-oem N/A  linux-firmware 20240318.git3b128b60-0ubuntu2.27 SourcePackage: linux-oem-6.17 UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 09/09/2025 dmi.bios.release: 1.4 dmi.bios.vendor: Dell Inc. dmi.bios.version: 1.4.1 dmi.board.name: 0WT010 dmi.board.vendor: Dell Inc. dmi.board.version: D01 dmi.chassis.type: 10 dmi.chassis.vendor: Dell Inc. dmi.ec.firmware.release: 1.3 dmi.modalias: dmi:bvnDellInc.:bvr1.4.1:bd09/09/2025:br1.4:efr1.3:svnDellInc.:pnDellProMax14MC14255:pvr:rvnDellInc.:rn0WT010:rvrD01:cvnDellInc.:ct10:cvr:sku0D80: dmi.product.family: Dell Pro Max Laptops dmi.product.name: Dell Pro Max 14 MC14255 dmi.product.sku: 0D80 dmi.sys.vendor: Dell Inc. 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