| Message ID | 20240409093645.456004-2-vinod.govindapillai@intel.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | iommu/vt-d: Fix WARN_ON in iommu probe path | expand |
+Jani On Tue, 2024-04-09 at 12:36 +0300, Vinod Govindapillai wrote: > From: Lu Baolu <baolu.lu@linux.intel.com> > > 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") > Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> > Signed-off-by: Vinod Govindapillai <vinod.govindapillai@intel.com> > --- > 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 50eb9aed47cc..a7ecd90303dc 100644 > --- a/drivers/iommu/intel/iommu.c > +++ b/drivers/iommu/intel/iommu.c > @@ -4299,9 +4299,11 @@ 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); > @@ -4336,7 +4338,8 @@ 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) &&
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 50eb9aed47cc..a7ecd90303dc 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4299,9 +4299,11 @@ 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); @@ -4336,7 +4338,8 @@ 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) &&