Commit 105c4256 authored by Arthur Husband's avatar Arthur Husband Committed by Niklas Cassel
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ata: ahci: force 32-bit DMA for JMicron JMB582/JMB585 



The JMicron JMB585 (and JMB582) SATA controllers advertise 64-bit DMA
support via the S64A bit in the AHCI CAP register, but their 64-bit DMA
implementation is defective. Under sustained I/O, DMA transfers targeting
addresses above 4GB silently corrupt data -- writes land at incorrect
memory addresses with no errors logged.

The failure pattern is similar to the ASMedia ASM1061
(commit 20730e9b ("ahci: add 43-bit DMA address quirk for ASMedia
ASM1061 controllers")), which also falsely advertised full 64-bit DMA
support. However, the JMB585 requires a stricter 32-bit DMA mask rather
than 43-bit, as corruption occurs with any address above 4GB.

On the Minisforum N5 Pro specifically, the combination of the JMB585's
broken 64-bit DMA with the AMD Family 1Ah (Strix Point) IOMMU causes
silent data corruption that is only detectable via checksumming
filesystems (BTRFS/ZFS scrub). The corruption occurs when 32-bit IOVA
space is exhausted and the kernel transparently switches to 64-bit DMA
addresses.

Add device-specific PCI ID entries for the JMB582 (0x0582) and JMB585
(0x0585) before the generic JMicron class match, using a new board type
that combines AHCI_HFLAG_IGN_IRQ_IF_ERR (preserving existing behavior)
with AHCI_HFLAG_32BIT_ONLY to force 32-bit DMA masks.

Signed-off-by: default avatarArthur Husband <artmoty@gmail.com>
Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Signed-off-by: default avatarNiklas Cassel <cassel@kernel.org>
parent e6d7eba2

drivers/ata/ahci.c

+14 −0
Original line number Diff line number Diff line
@@ -68,6 +68,7 @@ enum board_ids { 
	/* board IDs for specific chipsets in alphabetical order */

	board_ahci_al,

	board_ahci_avn,

	board_ahci_jmb585,

	board_ahci_mcp65,

	board_ahci_mcp77,

	board_ahci_mcp89,
@@ -212,6 +213,15 @@ static const struct ata_port_info ahci_port_info[] = { 
		.udma_mask	= ATA_UDMA6,

		.port_ops	= &ahci_avn_ops,

	},

	/* JMicron JMB582/585: 64-bit DMA is broken, force 32-bit */

	[board_ahci_jmb585] = {

		AHCI_HFLAGS	(AHCI_HFLAG_IGN_IRQ_IF_ERR |

				 AHCI_HFLAG_32BIT_ONLY),

		.flags		= AHCI_FLAG_COMMON,

		.pio_mask	= ATA_PIO4,

		.udma_mask	= ATA_UDMA6,

		.port_ops	= &ahci_ops,

	},

	[board_ahci_mcp65] = {

		AHCI_HFLAGS	(AHCI_HFLAG_NO_FPDMA_AA | AHCI_HFLAG_NO_PMP |

				 AHCI_HFLAG_YES_NCQ),
@@ -439,6 +449,10 @@ static const struct pci_device_id ahci_pci_tbl[] = { 
	/* Elkhart Lake IDs 0x4b60 & 0x4b62 https://sata-io.org/product/8803 not tested yet */

	{ PCI_VDEVICE(INTEL, 0x4b63), board_ahci_pcs_quirk }, /* Elkhart Lake AHCI */



	/* JMicron JMB582/585: force 32-bit DMA (broken 64-bit implementation) */

	{ PCI_VDEVICE(JMICRON, 0x0582), board_ahci_jmb585 },

	{ PCI_VDEVICE(JMICRON, 0x0585), board_ahci_jmb585 },



	/* JMicron 360/1/3/5/6, match class to avoid IDE function */

	{ PCI_VENDOR_ID_JMICRON, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,

	  PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff, board_ahci_ign_iferr },