JMicron JMB585 AHCI controller fails to probe on kernel 6.18.29 (error -12 / ENOMEM) - Raspberry Pi 5

[vlonexo1]

Describe the bug

After upgrading to kernel 6.18.29, the JMicron JMB585 SATA controller on a SATA HAT (Radxa Penta SATA Hat Top Board) fails to initialize at boot. The drive is completely absent from lsblk — no /dev/sda at all. The blue activity light on the HAT never comes on during boot.

The relevant dmesg error on 6.18.29:
ahci 0001:01:00.0: probe with driver ahci failed with error -12

Error -12 is ENOMEM — the AHCI controller fails to allocate memory during probe. Updating the EEPROM from 1765222194 (Dec 8 2025) to 1778498402 (May 11 2026) did not resolve the issue. Rolling back to 6.12.75 restores normal operation immediately.

Note: this appears distinct from the NVMe boot failures in #7367. The failure mode is ENOMEM at AHCI probe time, not an LVM/mount failure.

Steps to reproduce the behaviour

1. Start on kernel 6.12.75 with SATA HAT (JMicron JMB585) working normally
2. Update EEPROM to latest (1778498402)
3. Run apt upgrade, which installs kernel 6.18.29 and updates kernel_2712.img
4. Reboot
5. SATA controller fails to probe — drive absent, no activity light on Radxa Penta SATA Hat Top Board

Device (s)

Raspberry Pi 5

System

OS: Raspberry Pi reference 2025-12-04 (OpenMediaVault, Debian 12 Bookworm)
Firmware: version 66f33f7e (release) 2026/05/11 12:20:02
Kernel: Linux stoneberry 6.12.75+rpt-rpi-2712 #1 SMP PREEMPT Debian 1:6.12.75-1+rpt1 (2026-03-11) aarch64 GNU/Linux
(Note: system info collected on working 6.12.75 — 6.18.29 cannot be logged into due to missing drive)

Logs

Working (6.12.75):
[ 2.018187] pci 0001:01:00.0: [197b:0585] type 00 class 0x010601 PCIe Legacy Endpoint
[ 6.606191] ahci 0001:01:00.0: version 3.0
[ 6.606449] ahci 0001:01:00.0: AHCI vers 0001.0301, 32 command slots, 6 Gbps, SATA mode
[ 6.620254] scsi host0: ahci
[ 6.624842] scsi host1: ahci
[ 6.629197] scsi host2: ahci
[ 6.629877] scsi host3: ahci
[ 6.689710] scsi host4: ahci

Broken (6.18.29):
[ 4.280801] ahci 0001:01:00.0: AHCI vers 0001.0301, 32 command slots, 6 Gbps, SATA mode
[ 4.284521] ahci 0001:01:00.0: probe with driver ahci failed with error -12

Additional context

EEPROM update from 1765222194 to 1778498402 was applied while on 6.12.75 before testing 6.18.29 — did not resolve the issue.

Workaround: sudo cp /boot/vmlinuz-6.12.75+rpt-rpi-2712 /boot/firmware/kernel_2712.img

[nbuchwitz]

Probably related to the JMB585 32-bit-DMA quirk in f5a5d0e. Try reverting the patch or even simpler, put dtoverlay=pcie-32bit-dma in /boot/firmware/config.txt

Maybe a proper fix would be to gate the quirk on IOMMU presence?

[popcornmix]

Likely duplicate of #7355

[vlonexo1]

Seemed like a duplicate to #7355.

Adding dtoverlay=pcie-32bit-dma-pi5 to /boot/firmware/config.txt under [all] resolved it. Now running 6.18.29 with the drive recognized and mounted correctly.