When updating a DTE, amd_iommu_setup_domain_device() would check if the update had been non-atomic (i.e rc > 0) and throw a warning if such non-atomic update could be dangerous. However since commit 3fc44151d83d, rc can no longer be positive, making this branch unreachable code.
No functional change intended. Signed-off-by: Teddy Astie <[email protected]> --- xen/drivers/passthrough/amd/pci_amd_iommu.c | 18 ------------------ 1 file changed, 18 deletions(-) diff --git a/xen/drivers/passthrough/amd/pci_amd_iommu.c b/xen/drivers/passthrough/amd/pci_amd_iommu.c index 3a14770855..02eee4e658 100644 --- a/xen/drivers/passthrough/amd/pci_amd_iommu.c +++ b/xen/drivers/passthrough/amd/pci_amd_iommu.c @@ -225,24 +225,6 @@ static int __must_check amd_iommu_setup_domain_device( spin_unlock_irqrestore(&iommu->lock, flags); return rc; } - if ( rc && - domain != pdev->domain && - /* - * By non-atomically updating the DTE's domain ID field last, - * during a short window in time TLB entries with the old domain - * ID but the new page tables may have been inserted. This could - * affect I/O of other devices using this same (old) domain ID. - * Such updating therefore is not a problem if this was the only - * device associated with the old domain ID. Diverting I/O of any - * of a dying domain's devices to the quarantine page tables is - * intended anyway. - */ - !pdev->domain->is_dying && - pdev->domain != dom_io && - (any_pdev_behind_iommu(pdev->domain, pdev, iommu) || - pdev->phantom_stride) ) - AMD_IOMMU_WARN(" %pp: reassignment may cause %pd data corruption\n", - &PCI_SBDF(pdev->seg, bus, devfn), pdev->domain); /* * Check remaining settings are still in place from an earlier call -- 2.51.2 -- Teddy Astie | Vates XCP-ng Developer XCP-ng & Xen Orchestra - Vates solutions web: https://vates.tech
