6.8-stable review patch. If anyone has any objections, please let me know.
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From: Lu Baolu baolu.lu@linux.intel.com
[ Upstream commit 89436f4f54125b1297aec1f466efd8acb4ec613d ]
Commit 1a75cc710b95 ("iommu/vt-d: Use rbtree to track iommu probed devices") adds all devices probed by the iommu driver in a rbtree indexed by the source ID of each device. It assumes that each device has a unique source ID. This assumption is incorrect and the VT-d spec doesn't state this requirement either.
The reason for using a rbtree to track devices is to look up the device with PCI bus and devfunc in the paths of handling ATS invalidation time out error and the PRI I/O page faults. Both are PCI ATS feature related.
Only track the devices that have PCI ATS capabilities in the rbtree to avoid unnecessary WARN_ON in the iommu probe path. Otherwise, on some platforms below kernel splat will be displayed and the iommu probe results in failure.
WARNING: CPU: 3 PID: 166 at drivers/iommu/intel/iommu.c:158 intel_iommu_probe_device+0x319/0xd90 Call Trace: <TASK> ? __warn+0x7e/0x180 ? intel_iommu_probe_device+0x319/0xd90 ? report_bug+0x1f8/0x200 ? handle_bug+0x3c/0x70 ? exc_invalid_op+0x18/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? intel_iommu_probe_device+0x319/0xd90 ? debug_mutex_init+0x37/0x50 __iommu_probe_device+0xf2/0x4f0 iommu_probe_device+0x22/0x70 iommu_bus_notifier+0x1e/0x40 notifier_call_chain+0x46/0x150 blocking_notifier_call_chain+0x42/0x60 bus_notify+0x2f/0x50 device_add+0x5ed/0x7e0 platform_device_add+0xf5/0x240 mfd_add_devices+0x3f9/0x500 ? preempt_count_add+0x4c/0xa0 ? up_write+0xa2/0x1b0 ? __debugfs_create_file+0xe3/0x150 intel_lpss_probe+0x49f/0x5b0 ? pci_conf1_write+0xa3/0xf0 intel_lpss_pci_probe+0xcf/0x110 [intel_lpss_pci] pci_device_probe+0x95/0x120 really_probe+0xd9/0x370 ? __pfx___driver_attach+0x10/0x10 __driver_probe_device+0x73/0x150 driver_probe_device+0x19/0xa0 __driver_attach+0xb6/0x180 ? __pfx___driver_attach+0x10/0x10 bus_for_each_dev+0x77/0xd0 bus_add_driver+0x114/0x210 driver_register+0x5b/0x110 ? __pfx_intel_lpss_pci_driver_init+0x10/0x10 [intel_lpss_pci] do_one_initcall+0x57/0x2b0 ? kmalloc_trace+0x21e/0x280 ? do_init_module+0x1e/0x210 do_init_module+0x5f/0x210 load_module+0x1d37/0x1fc0 ? init_module_from_file+0x86/0xd0 init_module_from_file+0x86/0xd0 idempotent_init_module+0x17c/0x230 __x64_sys_finit_module+0x56/0xb0 do_syscall_64+0x6e/0x140 entry_SYSCALL_64_after_hwframe+0x71/0x79
Fixes: 1a75cc710b95 ("iommu/vt-d: Use rbtree to track iommu probed devices") Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/10689 Signed-off-by: Lu Baolu baolu.lu@linux.intel.com Link: https://lore.kernel.org/r/20240407011429.136282-1-baolu.lu@linux.intel.com Reviewed-by: Kevin Tian kevin.tian@intel.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/intel/iommu.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 5dba58f322f03..d7e10f1311aaf 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4381,9 +4381,11 @@ static struct iommu_device *intel_iommu_probe_device(struct device *dev) }
dev_iommu_priv_set(dev, info); - ret = device_rbtree_insert(iommu, info); - if (ret) - goto free; + if (pdev && pci_ats_supported(pdev)) { + ret = device_rbtree_insert(iommu, info); + if (ret) + goto free; + }
if (sm_supported(iommu) && !dev_is_real_dma_subdevice(dev)) { ret = intel_pasid_alloc_table(dev); @@ -4410,7 +4412,8 @@ static void intel_iommu_release_device(struct device *dev) struct intel_iommu *iommu = info->iommu;
mutex_lock(&iommu->iopf_lock); - device_rbtree_remove(info); + if (dev_is_pci(dev) && pci_ats_supported(to_pci_dev(dev))) + device_rbtree_remove(info); mutex_unlock(&iommu->iopf_lock);
if (sm_supported(iommu) && !dev_is_real_dma_subdevice(dev) &&