kernel/linux.git/drivers/pci/endpoint, branch v6.1.168

PCI: endpoint: Fix swapped parameters in pci_{primary/secondary}_epc_epf_unlink() functions

2026-03-04T12:20:49+00:00

[ Upstream commit 8754dd7639ab0fd68c3ab9d91c7bdecc3e5740a8 ] struct configfs_item_operations callbacks are defined like the following: int (*allow_link)(struct config_item *src, struct config_item *target); void (*drop_link)(struct config_item *src, struct config_item *target); While pci_primary_epc_epf_link() and pci_secondary_epc_epf_link() specify the parameters in the correct order, pci_primary_epc_epf_unlink() and pci_secondary_epc_epf_unlink() specify the parameters in the wrong order, leading to the below kernel crash when using the unlink command in configfs: Unable to handle kernel paging request at virtual address 0000000300000857 Mem abort info: ... pc : string+0x54/0x14c lr : vsnprintf+0x280/0x6e8 ... string+0x54/0x14c vsnprintf+0x280/0x6e8 vprintk_default+0x38/0x4c vprintk+0xc4/0xe0 pci_epf_unbind+0xdc/0x108 configfs_unlink+0xe0/0x208+0x44/0x74 vfs_unlink+0x120/0x29c __arm64_sys_unlinkat+0x3c/0x90 invoke_syscall+0x48/0x134 do_el0_svc+0x1c/0x30prop.0+0xd0/0xf0 Fixes: e85a2d783762 ("PCI: endpoint: Add support in configfs to associate two EPCs with EPF") Signed-off-by: Manikanta Maddireddy [mani: cced stable, changed commit message as per https://lore.kernel.org/linux-pci/aV9joi3jF1R6ca02@ryzen] Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Reviewed-by: Niklas Cassel Reviewed-by: Frank Li Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260108062747.1870669-1-mmaddireddy@nvidia.com Signed-off-by: Sasha Levin

PCI: endpoint: Avoid creating sub-groups asynchronously

2026-02-19T15:25:16+00:00

[ Upstream commit 7c5c7d06bd1f86d2c3ebe62be903a4ba42db4d2c ] The asynchronous creation of sub-groups by a delayed work could lead to a NULL pointer dereference when the driver directory is removed before the work completes. The crash can be easily reproduced with the following commands: # cd /sys/kernel/config/pci_ep/functions/pci_epf_test # for i in {1..20}; do mkdir test && rmdir test; done BUG: kernel NULL pointer dereference, address: 0000000000000088 ... Call Trace: configfs_register_group+0x3d/0x190 pci_epf_cfs_work+0x41/0x110 process_one_work+0x18f/0x350 worker_thread+0x25a/0x3a0 Fix this issue by using configfs_add_default_group() API which does not have the deadlock problem as configfs_register_group() and does not require the delayed work handler. Fixes: e85a2d783762 ("PCI: endpoint: Add support in configfs to associate two EPCs with EPF") Signed-off-by: Liu Song [mani: slightly reworded the description and added stable list] Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Cc: stable@kernel.org Link: https://patch.msgid.link/20250710143845409gLM6JdlwPhlHG9iX3F6jK@zte.com.cn Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

PCI: endpoint: Remove unused field in struct pci_epf_group

2026-02-19T15:25:16+00:00

[ Upstream commit 328e4dffbeecc0f2cc5a149dee6c11a0577c9671 ] In "struct pci_epf_group", the 'type_group' field is unused. This was added, but already unused, by commit 70b3740f2c19 ("PCI: endpoint: Automatically create a function specific attributes group"). Thus, remove it. Found with cppcheck, unusedStructMember. [kwilczynski: commit log] Link: https://lore.kernel.org/linux-pci/6507d44b6c60a19af35a605e2d58050be8872ab6.1712341008.git.christophe.jaillet@wanadoo.fr Signed-off-by: Christophe JAILLET Signed-off-by: Krzysztof Wilczyński Signed-off-by: Bjorn Helgaas Stable-dep-of: 7c5c7d06bd1f ("PCI: endpoint: Avoid creating sub-groups asynchronously") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

PCI: endpoint: Automatically create a function specific attributes group

2026-02-19T15:25:16+00:00

[ Upstream commit 70b3740f2c1941e2006d61539131b70d20cba9a6 ] A PCI endpoint function driver can define function specific attributes under its function configfs directory using the add_cfs() endpoint driver operation. This is done by tying up the mkdir operation for the function configfs directory to a call to the add_cfs() operation. However, there are no checks preventing the user from repeatedly creating function specific attribute directories with different names, resulting in the same endpoint specific attributes group being added multiple times, which also result in an invalid reference counting for the attribute groups. E.g., using the pci-epf-ntb function driver as an example, the user creates the function as follows: $ modprobe pci-epf-ntb $ cd /sys/kernel/config/pci_ep/functions/pci_epf_ntb $ mkdir func0 $ tree func0 func0/ |-- baseclass_code |-- cache_line_size |-- ... `-- vendorid $ mkdir func0/attrs $ tree func0 func0/ |-- attrs | |-- db_count | |-- mw1 | |-- mw2 | |-- mw3 | |-- mw4 | |-- num_mws | `-- spad_count |-- baseclass_code |-- cache_line_size |-- ... `-- vendorid At this point, the function can be started by linking the EP controller. However, if the user mistakenly creates again a directory: $ mkdir func0/attrs2 $ tree func0 func0/ |-- attrs | |-- db_count | |-- mw1 | |-- mw2 | |-- mw3 | |-- mw4 | |-- num_mws | `-- spad_count |-- attrs2 | |-- db_count | |-- mw1 | |-- mw2 | |-- mw3 | |-- mw4 | |-- num_mws | `-- spad_count |-- baseclass_code |-- cache_line_size |-- ... `-- vendorid The endpoint function specific attributes are duplicated and cause a crash when the endpoint function device is torn down: refcount_t: addition on 0; use-after-free. WARNING: CPU: 2 PID: 834 at lib/refcount.c:25 refcount_warn_saturate+0xc8/0x144 CPU: 2 PID: 834 Comm: rmdir Not tainted 6.3.0-rc1 #1 Hardware name: Pine64 RockPro64 v2.1 (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) ... Call trace: refcount_warn_saturate+0xc8/0x144 config_item_get+0x7c/0x80 configfs_rmdir+0x17c/0x30c vfs_rmdir+0x8c/0x204 do_rmdir+0x158/0x184 __arm64_sys_unlinkat+0x64/0x80 invoke_syscall+0x48/0x114 ... Fix this by modifying pci_epf_cfs_work() to execute the new function pci_ep_cfs_add_type_group() which itself calls pci_epf_type_add_cfs() to obtain the function specific attribute group and the group name (directory name) from the endpoint function driver. If the function driver defines an attribute group, pci_ep_cfs_add_type_group() then proceeds to register this group using configfs_register_group(), thus automatically exposing the function type specific configfs attributes to the user. E.g.: $ modprobe pci-epf-ntb $ cd /sys/kernel/config/pci_ep/functions/pci_epf_ntb $ mkdir func0 $ tree func0 func0/ |-- baseclass_code |-- cache_line_size |-- ... |-- pci_epf_ntb.0 | |-- db_count | |-- mw1 | |-- mw2 | |-- mw3 | |-- mw4 | |-- num_mws | `-- spad_count |-- primary |-- ... `-- vendorid With this change, there is no need for the user to create or delete directories in the endpoint function attributes directory. The pci_epf_type_group_ops group operations are thus removed. Also update the documentation for the pci-epf-ntb and pci-epf-vntb function drivers to reflect this change, removing the explanations showing the need to manually create the sub-directory for the function specific attributes. Link: https://lore.kernel.org/r/20230415023542.77601-2-dlemoal@kernel.org Signed-off-by: Damien Le Moal Signed-off-by: Lorenzo Pieralisi Signed-off-by: Bjorn Helgaas Reviewed-by: Manivannan Sadhasivam Stable-dep-of: 7c5c7d06bd1f ("PCI: endpoint: Avoid creating sub-groups asynchronously") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

PCI: endpoint: pci-epf-test: Add NULL check for DMA channels before release

2025-10-19T14:23:20+00:00

[ Upstream commit 85afa9ea122dd9d4a2ead104a951d318975dcd25 ] The fields dma_chan_tx and dma_chan_rx of the struct pci_epf_test can be NULL even after EPF initialization. Then it is prudent to check that they have non-NULL values before releasing the channels. Add the checks in pci_epf_test_clean_dma_chan(). Without the checks, NULL pointer dereferences happen and they can lead to a kernel panic in some cases: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000050 Call trace: dma_release_channel+0x2c/0x120 (P) pci_epf_test_epc_deinit+0x94/0xc0 [pci_epf_test] pci_epc_deinit_notify+0x74/0xc0 tegra_pcie_ep_pex_rst_irq+0x250/0x5d8 irq_thread_fn+0x34/0xb8 irq_thread+0x18c/0x2e8 kthread+0x14c/0x210 ret_from_fork+0x10/0x20 Fixes: 8353813c88ef ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities") Fixes: 5ebf3fc59bd2 ("PCI: endpoint: functions/pci-epf-test: Add DMA support to transfer data") Signed-off-by: Shin'ichiro Kawasaki [mani: trimmed the stack trace] Signed-off-by: Manivannan Sadhasivam Reviewed-by: Damien Le Moal Reviewed-by: Krzysztof Wilczyński Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250916025756.34807-1-shinichiro.kawasaki@wdc.com Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

PCI: endpoint: Remove surplus return statement from pci_epf_test_clean_dma_chan()

2025-10-19T14:23:20+00:00

[ Upstream commit 9b80bdb10aee04ce7289896e6bdad13e33972636 ] Remove a surplus return statement from the void function that has been added in the commit commit 8353813c88ef ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities"). Especially, as an empty return statements at the end of a void functions serve little purpose. This fixes the following checkpatch.pl script warning: WARNING: void function return statements are not generally useful #296: FILE: drivers/pci/endpoint/functions/pci-epf-test.c:296: + return; +} Link: https://lore.kernel.org/r/tencent_F250BEE2A65745A524E2EFE70CF615CA8F06@qq.com Signed-off-by: Wang Jiang [kwilczynski: commit log] Signed-off-by: Krzysztof Wilczyński Stable-dep-of: 85afa9ea122d ("PCI: endpoint: pci-epf-test: Add NULL check for DMA channels before release") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

PCI: endpoint: Fix configfs group removal on driver teardown

2025-08-28T14:26:07+00:00

commit 910bdb8197f9322790c738bb32feaa11dba26909 upstream. An endpoint driver configfs attributes group is added to the epf_group list of struct pci_epf_driver by pci_epf_add_cfs() but an added group is not removed from this list when the attribute group is unregistered with pci_ep_cfs_remove_epf_group(). Add the missing list_del() call in pci_ep_cfs_remove_epf_group() to correctly remove the attribute group from the driver list. With this change, once the loop over all attribute groups in pci_epf_remove_cfs() completes, the driver epf_group list should be empty. Add a WARN_ON() to make sure of that. Fixes: ef1433f717a2 ("PCI: endpoint: Create configfs entry for each pci_epf_device_id table entry") Signed-off-by: Damien Le Moal Signed-off-by: Manivannan Sadhasivam Reviewed-by: Niklas Cassel Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250624114544.342159-3-dlemoal@kernel.org Signed-off-by: Greg Kroah-Hartman

PCI: endpoint: Fix configfs group list head handling

2025-08-28T14:26:07+00:00

commit d79123d79a8154b4318529b7b2ff7e15806f480b upstream. Doing a list_del() on the epf_group field of struct pci_epf_driver in pci_epf_remove_cfs() is not correct as this field is a list head, not a list entry. This list_del() call triggers a KASAN warning when an endpoint function driver which has a configfs attribute group is torn down: ================================================================== BUG: KASAN: slab-use-after-free in pci_epf_remove_cfs+0x17c/0x198 Write of size 8 at addr ffff00010f4a0d80 by task rmmod/319 CPU: 3 UID: 0 PID: 319 Comm: rmmod Not tainted 6.16.0-rc2 #1 NONE Hardware name: Radxa ROCK 5B (DT) Call trace: show_stack+0x2c/0x84 (C) dump_stack_lvl+0x70/0x98 print_report+0x17c/0x538 kasan_report+0xb8/0x190 __asan_report_store8_noabort+0x20/0x2c pci_epf_remove_cfs+0x17c/0x198 pci_epf_unregister_driver+0x18/0x30 nvmet_pci_epf_cleanup_module+0x24/0x30 [nvmet_pci_epf] __arm64_sys_delete_module+0x264/0x424 invoke_syscall+0x70/0x260 el0_svc_common.constprop.0+0xac/0x230 do_el0_svc+0x40/0x58 el0_svc+0x48/0xdc el0t_64_sync_handler+0x10c/0x138 el0t_64_sync+0x198/0x19c ... Remove this incorrect list_del() call from pci_epf_remove_cfs(). Fixes: ef1433f717a2 ("PCI: endpoint: Create configfs entry for each pci_epf_device_id table entry") Signed-off-by: Damien Le Moal Signed-off-by: Manivannan Sadhasivam Reviewed-by: Niklas Cassel Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250624114544.342159-2-dlemoal@kernel.org Signed-off-by: Greg Kroah-Hartman

PCI: endpoint: pci-epf-vntb: Fix the incorrect usage of __iomem attribute

2025-08-15T10:05:04+00:00

[ Upstream commit 61ae7f8694fb4b57a8c02a1a8d2b601806afc999 ] __iomem attribute is supposed to be used only with variables holding the MMIO pointer. But here, 'mw_addr' variable is just holding a 'void *' returned by pci_epf_alloc_space(). So annotating it with __iomem is clearly wrong. Hence, drop the attribute. This also fixes the below sparse warning: drivers/pci/endpoint/functions/pci-epf-vntb.c:524:17: warning: incorrect type in assignment (different address spaces) drivers/pci/endpoint/functions/pci-epf-vntb.c:524:17: expected void [noderef] __iomem *mw_addr drivers/pci/endpoint/functions/pci-epf-vntb.c:524:17: got void * drivers/pci/endpoint/functions/pci-epf-vntb.c:530:21: warning: incorrect type in assignment (different address spaces) drivers/pci/endpoint/functions/pci-epf-vntb.c:530:21: expected unsigned int [usertype] *epf_db drivers/pci/endpoint/functions/pci-epf-vntb.c:530:21: got void [noderef] __iomem *mw_addr drivers/pci/endpoint/functions/pci-epf-vntb.c:542:38: warning: incorrect type in argument 2 (different address spaces) drivers/pci/endpoint/functions/pci-epf-vntb.c:542:38: expected void *addr drivers/pci/endpoint/functions/pci-epf-vntb.c:542:38: got void [noderef] __iomem *mw_addr Fixes: e35f56bb0330 ("PCI: endpoint: Support NTB transfer between RC and EP") Signed-off-by: Manivannan Sadhasivam Reviewed-by: Frank Li Link: https://patch.msgid.link/20250709125022.22524-1-mani@kernel.org Signed-off-by: Sasha Levin

PCI: endpoint: pci-epf-vntb: Return -ENOENT if pci_epc_get_next_free_bar() fails

2025-08-15T10:05:01+00:00

[ Upstream commit 7ea488cce73263231662e426639dd3e836537068 ] According the function documentation of epf_ntb_init_epc_bar(), the function should return an error code on error. However, it returns -1 when no BAR is available i.e., when pci_epc_get_next_free_bar() fails. Return -ENOENT instead. Fixes: e35f56bb0330 ("PCI: endpoint: Support NTB transfer between RC and EP") Signed-off-by: Jerome Brunet [mani: changed err code to -ENOENT] Signed-off-by: Manivannan Sadhasivam Reviewed-by: Frank Li Link: https://patch.msgid.link/20250603-pci-vntb-bar-mapping-v2-1-fc685a22ad28@baylibre.com Signed-off-by: Sasha Levin