Linux PCI subsystem development
 help / color / mirror / Atom feed
From: Michael Stolovitzsky <emestee@catnarok.net>
To: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
	Michael Stolovitzsky <emestee@catnarok.net>
Subject: [PATCH] PCI: Add function 1 DMA alias quirk for Toshiba AHCI SSD controller
Date: Tue, 29 Sep 2026 18:09:24 +0300	[thread overview]
Message-ID: <20260929150924.2376309-1-emestee@catnarok.net> (raw)

The Toshiba AHCI SATA controller [1179:010b] (subsystem [1b4b:9183])
used in 11-inch MacBook Air models (MacBookAir6,1 and MacBookAir7,1)
issues DMA with the requester ID of function 1, which does not exist.
With the Intel IOMMU enabled (intel_iommu=on, or
CONFIG_INTEL_IOMMU_DEFAULT_ON=y), these DMA writes are blocked, IDENTIFY
fails and the internal disk never appears:

  DMAR: [DMA Write NO_PASID] Request device [0000:04:00.1] fault addr 0xfffe0000 [fault reason 0x02] Present bit in context entry is clear
  ata1.00: failed to IDENTIFY (INIT_DEV_PARAMS failed, err_mask=0x80)

Add the controller to the quirk_dma_func1_alias() list. With it, the
SSD is identified and the system boots with the IOMMU enabled.

Link: https://github.com/omacom/omarchy/issues/12097
Link: https://github.com/omacom/omarchy/issues/13010
Cc: stable@vger.kernel.org
Assisted-by: Claude Opus 5.5
Signed-off-by: Michael Stolovitzsky <emestee@catnarok.net>
---
Tested on a MacBookAir6,1 (7.2.5-based kernel, intel_iommu=on);
build-tested on v7.3-rc5.

As far as I can tell, 1179:010b is specific to the Toshiba SSDs Apple
shipped in the 11-inch MacBook Air: pci.ids has no entry for it, and
every linux-hardware.org probe carrying it is a MacBookAir6,1 or 7,1.

 drivers/pci/quirks.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index de9bbccda..9d2ca995b 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4366,6 +4366,9 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_JMICRON,
 DECLARE_PCI_FIXUP_HEADER(0x1c28, /* Lite-On */
 			 0x0122, /* Plextor M6E (Marvell 88SS9183)*/
 			 quirk_dma_func1_alias);
+/* Toshiba AHCI SSD controller in MacBookAir6,1 and MacBookAir7,1 */
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_TOSHIBA, 0x010b,
+			 quirk_dma_func1_alias);
 
 /*
  * Some devices DMA with the wrong devfn, not just the wrong function.

base-commit: 72d3fcf802c45d00b300f25b848a93c3a2bd7c7e
-- 
2.55.0


             reply	other threads:[~2026-09-29 15:16 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-09-29 15:09 Michael Stolovitzsky [this message]
2026-09-29 15:20 ` [PATCH] PCI: Add function 1 DMA alias quirk for Toshiba AHCI SSD controller sashiko-bot

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260929150924.2376309-1-emestee@catnarok.net \
    --to=emestee@catnarok.net \
    --cc=bhelgaas@google.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox