iommu_attach_group_handle(9)

okay bestie, welcome to the iommu_attach_group_handle(9) page from the Kernel API Manual 💖✨ this one is all about attaching an IOMMU domain to an IOMMU group, and it’s lowkey iconic for fault delivery. let’s get into it.

🌸 NAME 🌸

iommu_attach_group_handle — Attach an IOMMU domain to an IOMMU group 💅

✨ SYNOPSIS ✨

the whole vibe:

int iommu_attach_group_handle (struct iommu_domain *domain , struct
iommu_group *group , struct iommu_attach_handle *handle );

🎀 ARGUMENTS 🎀

• domain — the IOMMU domain you’re attaching, periodt.
• group — the IOMMU group that will be attached, no cap.
• handle — the attach handle. keep it new, bestie, we’ll get to that.

🦋 DESCRIPTION 🦋

okay so first thing: this returns 0 on success and error code on failure. that’s the whole mood ✅

this is a variant of iommu_attach_group. it lets the caller provide an attach handle and use it when the domain is attached. this is currently used by IOMMUFD to deliver the I/O page faults 💅

caller should always provide a new handle to avoid race with the paths that have lockless reference to handle. not me stressing this, but bestie please listen: new handle, always. this is a real race-avoidance warning, fr fr ⚠️

🌈 SEE ALSO 🌈

Kernel file: ./drivers/iommu/iommu.c

the whole friend group:

• iommu_device_register(9)
• iommu_insert_resv_region(9)
• iommu_group_alloc(9)
• iommu_group_get_iommudata(9)
• iommu_group_set_iommudata(9)
• iommu_group_set_name(9)
• iommu_group_add_device(9)
• iommu_group_remove_device(9)
• iommu_group_mutex_assert(9)
• iommu_group_for_each_dev(9)
• iommu_group_get(9)
• iommu_group_ref_get(9)
• iommu_group_put(9)
• iommu_group_id(9)
• device_iommu_capable(9)
• iommu_group_has_isolated_msi(9)
• iommu_set_fault_handler(9)
• iommu_paging_domain_alloc_flags(9)
• iommu_attach_device(9)
• iommu_get_domain_for_dev(9)
• iommu_driver_get_domain_for_dev(9)
• iommu_attach_group(9)
• iommu_unmap(9)
• iommu_unmap_fast(9)
• report_iommu_fault(9)
• iommu_get_resv_regions(9)
• iommu_put_resv_regions(9)
• iommu_setup_default_domain(9)
• iommu_device_use_default_domain(9)
• iommu_device_unuse_default_domain(9)
• iommu_group_claim_dma_owner(9)
• iommu_device_claim_dma_owner(9)
• iommu_group_release_dma_owner(9)
• iommu_device_release_dma_owner(9)
• iommu_group_dma_owner_claimed(9)
• iommu_replace_device_pasid(9)
• iommu_attach_handle_get(9)
• iommu_detach_group_handle(9)
• iommu_replace_group_handle(9)
• pci_dev_reset_iommu_prepare(9)
• pci_dev_reset_iommu_done(9)
• iommu_dma_prepare_msi(9)

okay that’s the page, bestie! this lil manual page comes from the source/version ./drivers/iommu, dated October 2026. slay, go attach responsibly 💖🎀