From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 11 Feb 2026 00:30:29 +0000 (-0800)
Subject: Merge tag 'irq-msi-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3381d7b2b3dd012d366b9ba9339f98d54bea69fd;p=thirdparty%2Fkernel%2Flinux.git

Merge tag 'irq-msi-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull MSI updates from Thomas Gleixner:
 "Updates for the [PCI] MSI subsystem:

   - Add interrupt redirection infrastructure

     Some PCI controllers use a single demultiplexing interrupt for the
     MSI interrupts of subordinate devices.

     This prevents setting the interrupt affinity of device interrupts,
     which causes device interrupts to be delivered to a single CPU.
     That obviously is counterproductive for multi-queue devices and
     interrupt balancing.

     To work around this limitation the new infrastructure installs a
     dummy irq_set_affinity() callback which captures the affinity mask
     and picks a redirection target CPU out of the mask.

     When the PCI controller demultiplexes the interrupts it invokes a
     new handling function in the core, which either runs the interrupt
     handler in the context of the target CPU or delegates it to
     irq_work on the target CPU.

   - Utilize the interrupt redirection mechanism in the PCI DWC host
     controller driver.

     This allows affinity control for the subordinate device MSI
     interrupts instead of being randomly executed on the CPU which runs
     the demultiplex handler.

   - Replace the binary 64-bit MSI flag with a DMA mask

     Some PCI devices have PCI_MSI_FLAGS_64BIT in the MSI capability,
     but implement less than 64 address bits. This breaks on platforms
     where such a device is assigned an MSI address higher than what's
     supported.

     With the binary 64-bit flag there is no other choice than disabling
     64-bit MSI support which leaves the device disfunctional.

     By using a DMA mask the address limit of a device can be described
     correctly which provides support for the above scenario.

   - Make use of the DMA mask based address limit in the hda/intel and
     radeon drivers to enable them on affected platforms

   - The usual small cleanups and improvements"

* tag 'irq-msi-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ALSA: hda/intel: Make MSI address limit based on the device DMA limit
  drm/radeon: Make MSI address limit based on the device DMA limit
  PCI/MSI: Check the device specific address mask in msi_verify_entries()
  PCI/MSI: Convert the boolean no_64bit_msi flag to a DMA address mask
  genirq/redirect: Prevent writing MSI message on affinity change
  PCI/MSI: Unmap MSI-X region on error
  genirq: Update effective affinity for redirected interrupts
  PCI: dwc: Enable MSI affinity support
  PCI: dwc: Code cleanup
  genirq: Add interrupt redirection infrastructure
  genirq/msi: Correct kernel-doc in <linux/msi.h>
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3381d7b2b3dd012d366b9ba9339f98d54bea69fd