[SRU][Q:raspi][PATCH 0/1] linux-raspi: kernel does not support memory limit capabilities (LP: #2137159)

[Juerg Haefliger]

BugLink: https://bugs.launchpad.net/bugs/2137159

[ Impact ]

docker update --memory=128M --memory-swap=128M <container> fails with
"Your kernel does not support memory limit capabilities or the cgroup is not mounted. Limitation discarded."
on linux-raspi 6.17.0-1006-raspi.

The docker command works fine on amd64 and riscv64.

The following mount exists:

cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot)


[ Fix ]

Don't disable the memory cgroup by default.

[ Test Case ]

1. Verify the above works.
2. Quick check: Verify /sys/fs/cgroup/memory.stat exists.

[ Where Problems Could Occur ]

Additional kernel code that runs at boot and when using the memory cgroup. Could cause the usual kernel issues: Crashes, hangs, freezes, splats, ...

[ Additional Information ]

ProblemType: Bug
DistroRelease: Ubuntu 25.10
Package: linux-image-6.17.0-1006-raspi 6.17.0-1006.6
ProcVersionSignature: Ubuntu 6.17.0-1006.6-raspi 6.17.2
Uname: Linux 6.17.0-1006-raspi aarch64
AlsaVersion: Advanced Linux Sound Architecture Driver Version k6.17.0-1006-raspi.
AplayDevices: Error: [Errno 2] No such file or directory: 'aplay'
ApportVersion: 2.33.1-0ubuntu3
Architecture: arm64
ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord'
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/controlC1', '/dev/snd/pcmC1D0p', '/dev/snd/by-path', '/dev/snd/controlC0', '/dev/snd/pcmC0D0p', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
CRDA: N/A
Card0.Amixer.info: Error: [Errno 2] No such file or directory: 'amixer'
Card0.Amixer.values: Error: [Errno 2] No such file or directory: 'amixer'
Card1.Amixer.info: Error: [Errno 2] No such file or directory: 'amixer'
Card1.Amixer.values: Error: [Errno 2] No such file or directory: 'amixer'
CasperMD5CheckResult: unknown
CloudArchitecture: aarch64
CloudID: nocloud
CloudName: unknown
CloudPlatform: nocloud
CloudSubPlatform: config-disk (/dev/nvme0n1p1)
Date: Sat Dec 27 02:56:56 2025
ImageMediaBuild: 20250415
Lspci-vt:
 -[0001:00]---00.0-[01]----00.0  Samsung Electronics Co Ltd NVMe SSD Controller PM9B1 (DRAM-less)
 -[0002:00]---00.0-[01]----00.0  Raspberry Pi Ltd RP1 PCIe 2.0 South Bridge
Lsusb:
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
 Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 005 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Lsusb-t:
 /:  Bus 001.Port 001: Dev 001, Class=root_hub, Driver=dwc2/1p, 480M
 /:  Bus 002.Port 001: Dev 001, Class=root_hub, Driver=xhci-hcd/2p, 480M
 /:  Bus 003.Port 001: Dev 001, Class=root_hub, Driver=xhci-hcd/1p, 5000M
 /:  Bus 004.Port 001: Dev 001, Class=root_hub, Driver=xhci-hcd/2p, 480M
 /:  Bus 005.Port 001: Dev 001, Class=root_hub, Driver=xhci-hcd/1p, 5000M
PciMultimedia:

ProcFB:

ProcKernelCmdLine: reboot=w coherent_pool=1M 8250.nr_uarts=1 pci=pcie_bus_safe cgroup_disable=memory numa_policy=interleave nvme.max_host_mem_size_mb=0  numa=fake=8 system_heap.max_order=0 smsc95xx.macaddr=2C:CF:67:FC:F8:DB vc_mem.mem_base=0x3fc00000 vc_mem.mem_size=0x40000000  console=ttyAMA0,115200 multipath=off dwc_otg.lpm_enable=0 console=tty1 root=LABEL=writable rootfstype=ext4 rootwait fixrtc
RelatedPackageVersions:
 firmware-sof   N/A
 linux-firmware 20250901.git993ff19b-0ubuntu1.4
RfKill: Error: [Errno 2] No such file or directory: 'rfkill'
SourcePackage: linux-raspi
UpgradeStatus: Upgraded to questing on 2025-12-19 (8 days ago)
acpidump:

Juerg Haefliger (1):
  UBUNTU: SAUCE: ARM{,64}: dts: bcm27xx: Don't disable memory cgroup

 arch/arm/boot/dts/broadcom/bcm2708-rpi-bt.dtsi  | 2 +-
 arch/arm/boot/dts/broadcom/bcm270x.dtsi         | 2 +-
 arch/arm/boot/dts/broadcom/bcm2711-rpi-cm4s.dts | 2 +-
 arch/arm/boot/dts/broadcom/bcm2711-rpi-ds.dtsi  | 2 +-
 arch/arm/boot/dts/broadcom/bcm271x-rpi-bt.dtsi  | 2 +-
 arch/arm64/boot/dts/broadcom/bcm2712-rpi.dtsi   | 2 +-
 6 files changed, 6 insertions(+), 6 deletions(-)

-- 
2.51.0