Public bug reported: SATA drives connected via a JMicron JMB585-based card on the Pi 5's PCIe FFC ribbon (M.2 HAT) are not detected under kernel 7.0.0-1011-raspi. The same hardware works correctly under 7.0.0-1008-raspi. The regression is caused by the AHCI controller being incorrectly forced into 32-bit DMA mode, after which the port fails to start with ENOMEM (-12) because the DMA32 zone is empty on this platform.
* Machine: Raspberry Pi 5 Model B Rev 1.1 * SATA controller: JMicron JMB585 (PCIe, via Pi 5 PCIe FFC ribbon / M.2 HAT) * Drive: ADATA SU650 256 GB (SATA SSD) * OS: Ubuntu 26.04 (arm64) Kernel versions * Working: 7.0.0-1008-raspi (built Tue Apr 7 13:00:46 UTC 2026) * Broken: 7.0.0-1011-raspi (built Tue May 26 13:56:04 UTC 2026) In the working kernel, the AHCI controller initialises with 64-bit DMA: ``` ahci 0001:01:00.0: flags: 64bit ncq sntf stag pm led clo pmp fbs pio slum part ccc apst boh ata2: SATA link up 6.0 Gbps sd 1:0:0:0: [sda] Attached SCSI disk ``` In the broken kernel, 64-bit DMA capability is misreported and the port fails to start: ``` ahci 0001:01:00.0: controller can't do 64bit DMA, forcing 32bit ahci 0001:01:00.0: flags: ncq sntf stag pm led clo pmp fbs pio slum part ccc apst boh ← "64bit" flag absent ahci 0001:01:00.0: failed to start port 0 (errno=-12) ahci 0001:01:00.0: probe with driver ahci failed with error -12 ``` Workaround: Adding `dtoverlay=pcie-32bit-dma-pi5` to /boot/firmware/config.txt pre-allocates a 32-bit DMA pool, allowing the port to start successfully. Hardware ref: https://wiki.geekworm.com/X1009 ** Affects: linux-raspi (Ubuntu) Importance: Undecided Status: New ** Tags: raspi -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2155978 Title: linux-raspi 7.0.0-1011: AHCI SATA drives not detected on Pi 5 — regression from 7.0.0-1008 (64-bit DMA misdetection, errno=-12) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-raspi/+bug/2155978/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
