powerpc/pseries/iommu: DLPAR ADD of pci device doesn't completely initialize pci_controller structure
PATCH v3 1/1 powerpc/pseries/iommu: DLPAR ADD of pci device doesn't completely initialize pci_controller structure
When a PCI device is Dynamically added, LPAR OOPS with NULL pointer exception.
Complete stack is as below
[ 211.239206] BUG: Kernel NULL pointer dereference on read at 0x00000030 [ 211.239210] Faulting instruction address: 0xc0000000006bbe5c [ 211.239214] Oops: Kernel access of bad area, sig: 11 [#1] [ 211.239218] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries [ 211.239223] Modules linked in: rpadlpar_io rpaphp rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs xsk_diag bonding nft_compat nf_tables nfnetlink rfkill binfmt_misc dm_multipath rpcrdma sunrpc rdma_ucm ib_srpt ib_isert iscsi_target_mod target_core_mod ib_umad ib_iser libiscsi scsi_transport_iscsi ib_ipoib rdma_cm iw_cm ib_cm mlx5_ib ib_uverbs ib_core pseries_rng drm drm_panel_orientation_quirks xfs libcrc32c mlx5_core mlxfw sd_mod t10_pi sg tls ibmvscsi ibmveth scsi_transport_srp vmx_crypto pseries_wdt psample dm_mirror dm_region_hash dm_log dm_mod fuse [ 211.239280] CPU: 17 PID: 2685 Comm: drmgr Not tainted 6.7.0-203405+ #66 [ 211.239284] Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_008) hv:phyp pSeries [ 211.239289] NIP: c0000000006bbe5c LR: c000000000a13e68 CTR: c0000000000579f8 [ 211.239293] REGS: c00000009924f240 TRAP: 0300 Not tainted (6.7.0-203405+) [ 211.239298] MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 24002220 XER: 20040006 [ 211.239306] CFAR: c000000000a13e64 DAR: 0000000000000030 DSISR: 40000000 IRQMASK: 0 [ 211.239306] GPR00: c000000000a13e68 c00000009924f4e0 c0000000015a2b00 0000000000000000 [ 211.239306] GPR04: c0000000013c5590 0000000000000000 c000000006d07970 c0000000d8f8f180 [ 211.239306] GPR08: 00000000000006ec c0000000d8f8f180 c000000002c35d58 0000000024002228 [ 211.239306] GPR12: c0000000000579f8 c0000003ffeb3880 0000000000000000 0000000000000000 [ 211.239306] GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [ 211.239306] GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [ 211.239306] GPR24: c0000000919460c0 0000000000000000 fffffffffffff000 c0000000010088e8 [ 211.239306] GPR28: c0000000013c5590 c000000006d07970 c0000000919460c0 c0000000919460c0 [ 211.239354] NIP [c0000000006bbe5c] sysfs_add_link_to_group+0x34/0x94 [ 211.239361] LR [c000000000a13e68] iommu_device_link+0x5c/0x118 [ 211.239367] Call Trace: [ 211.239369] [c00000009924f4e0] [c000000000a109b8] iommu_init_device+0x26c/0x318 (unreliable) [ 211.239376] [c00000009924f520] [c000000000a13e68] iommu_device_link+0x5c/0x118 [ 211.239382] [c00000009924f560] [c000000000a107f4] iommu_init_device+0xa8/0x318 [ 211.239387] [c00000009924f5c0] [c000000000a11a08] iommu_probe_device+0xc0/0x134 [ 211.239393] [c00000009924f600] [c000000000a11ac0] iommu_bus_notifier+0x44/0x104 [ 211.239398] [c00000009924f640] [c00000000018dcc0] notifier_call_chain+0xb8/0x19c [ 211.239405] [c00000009924f6a0] [c00000000018df88] blocking_notifier_call_chain+0x64/0x98 [ 211.239411] [c00000009924f6e0] [c000000000a250fc] bus_notify+0x50/0x7c [ 211.239416] [c00000009924f720] [c000000000a20838] device_add+0x640/0x918 [ 211.239421] [c00000009924f7f0] [c0000000008f1a34] pci_device_add+0x23c/0x298 [ 211.239427] [c00000009924f840] [c000000000077460] of_create_pci_dev+0x400/0x884 [ 211.239432] [c00000009924f8e0] [c000000000077a08] of_scan_pci_dev+0x124/0x1b0 [ 211.239437] [c00000009924f980] [c000000000077b0c] __of_scan_bus+0x78/0x18c [ 211.239442] [c00000009924fa10] [c000000000073f90] pcibios_scan_phb+0x2a4/0x3b0 [ 211.239447] [c00000009924fad0] [c0000000001007a8] init_phb_dynamic+0xb8/0x110 [ 211.239453] [c00000009924fb40] [c008000006920620] dlpar_add_slot+0x170/0x3b8 [rpadlpar_io] [ 211.239461] [c00000009924fbe0] [c008000006920d64] add_slot_store.part.0+0xb4/0x130 [rpadlpar_io] [ 211.239468] [c00000009924fc70] [c000000000fb4144] kobj_attr_store+0x2c/0x48 [ 211.239473] [c00000009924fc90] [c0000000006b90e4] sysfs_kf_write+0x64/0x78 [ 211.239479] [c00000009924fcb0] [c0000000006b7b78] kernfs_fop_write_iter+0x1b0/0x290 [ 211.239485] [c00000009924fd00] [c0000000005b6fdc] vfs_write+0x350/0x4a0 [ 211.239491] [c00000009924fdc0] [c0000000005b7450] ksys_write+0x84/0x140 [ 211.239496] [c00000009924fe10] [c000000000030a04] system_call_exception+0x124/0x330 [ 211.239502] [c00000009924fe50] [c00000000000cedc] system_call_vectored_common+0x15c/0x2ec
Commit a940904443e4 ("powerpc/iommu: Add iommu_ops to report capabilities and allow blocking domains") broke DLPAR ADD of pci devices.
The above added iommu_device structure to pci_controller. During system boot, pci devices are discovered and this newly added iommu_device structure initialized by a call to iommu_device_register().
During DLPAR ADD of a PCI device, a new pci_controller structure is allocated but there are no calls made to iommu_device_register() interface.
Fix would be to register iommu device during DLPAR ADD as well.
Fixes a940904443e4 ("powerpc/iommu: Add iommu_ops to report capabilities and allow blocking domains")
Signed-off-by Gaurav Batra <[email protected]>
Reviewed-by Brian King <[email protected]>
--- arch/powerpc/include/asm/ppc-pci.h | 10 ++++++++++ arch/powerpc/kernel/iommu.c | 23 ++++++++++++++++------ arch/powerpc/platforms/pseries/pci_dlpar.c | 4 ++++ 3 files changed, 31 insertions(+), 6 deletions(-)
arch/powerpc/include/asm/ppc-pci.h +10 -0
@@ -30,6 +30,16 @@ void *pci_traverse_device_nodes(struct device_node *start, void *data);extern void pci_devs_phb_init_dynamic (struct pci_controller *phb); +#if defined(CONFIG_IOMMU_API ) && (defined(CONFIG_PPC_PSERIES ) || \ + defined(CONFIG_PPC_POWERNV )) +extern void ppc_iommu_register_device (struct pci_controller *phb); +extern void ppc_iommu_unregister_device (struct pci_controller *phb); +#else +static inline void ppc_iommu_register_device (struct pci_controller *phb) { } +static inline void ppc_iommu_unregister_device (struct pci_controller *phb) { } +#endif + +/* From rtas_pci.h */ extern void init_pci_config_tokens (void );extern unsigned long get_phb_buid (struct device_node *);
arch/powerpc/kernel/iommu.c +17 -6
@@ -1339,7 +1339,7 @@ static struct iommu_device *spapr_tce_iommu_probe_device(struct device *dev)struct pci_controller *hose;if (!dev_is_pci (dev)) -return ERR_PTR (-EPERM ); +return ERR_PTR (-ENODEV ); pdev =to_pci_dev (dev); hose = pdev->bus->sysdata;
@@ -1388,6 +1388,21 @@ static const struct attribute_group *spapr_tce_iommu_groups[] = { NULL, }; +void ppc_iommu_register_device (struct pci_controller *phb) +{ +iommu_device_sysfs_add (&phb->iommu, phb->parent, + spapr_tce_iommu_groups,"iommu-phb%04x" , + phb->global_number); +iommu_device_register (&phb->iommu, &spapr_tce_iommu_ops, + phb->parent); +} + +void ppc_iommu_unregister_device (struct pci_controller *phb) +{ +iommu_device_unregister (&phb->iommu); +iommu_device_sysfs_remove (&phb->iommu); +} +/* * This registers IOMMU devices of PHBs. This needs to happen * after core_initcall(iommu_init) + postcore_initcall(pci_driver_init) and
@@ -1398,11 +1413,7 @@ static int __init spapr_tce_setup_phb_iommus_initcall(void)struct pci_controller *hose;list_for_each_entry (hose, &hose_list, list_node) { -iommu_device_sysfs_add (&hose->iommu, hose->parent, - spapr_tce_iommu_groups,"iommu-phb%04x" , - hose->global_number); -iommu_device_register (&hose->iommu, &spapr_tce_iommu_ops, - hose->parent); +ppc_iommu_register_device (hose); }return 0 ; }
arch/powerpc/platforms/pseries/pci_dlpar.c +4 -0
@@ -35,6 +35,8 @@ struct pci_controller *init_phb_dynamic(struct device_node *dn)pseries_msi_allocate_domains (phb); +ppc_iommu_register_device (phb); +/* Create EEH devices for the PHB */ eeh_phb_pe_create (phb);
@@ -76,6 +78,8 @@ int remove_phb_dynamic(struct pci_controller *phb) } } +ppc_iommu_unregister_device (phb); +pseries_msi_free_domains (phb);/* Keep a reference so phb isn't freed yet */
base-commit: ecb1b8288dc7ccbdcb3b9df005fa1c0e0c0388a7
Signature · 1 line
2.39.3 (Apple Git-145)
Michael Ellerman
AppliedQuoted 10 lines · Gaurav Batra
When a PCI device is Dynamically added, LPAR OOPS with NULL pointer exception.
Complete stack is as below
[ 211.239206] BUG: Kernel NULL pointer dereference on read at 0x00000030 [ 211.239210] Faulting instruction address: 0xc0000000006bbe5c [ 211.239214] Oops: Kernel access of bad area, sig: 11 [#1] [ 211.239218] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries[...]
Applied to powerpc/fixes.
[1/1] powerpc/pseries/iommu: DLPAR ADD of pci device doesn't completely initialize pci_controller structure
https://git.kernel.org/powerpc/c/a5c57fd2e9bd1c8ea8613a8f94fd0be5eccbf321
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