Hi Vidya Sagar, On 22/06/22 11:07, Vidya Sagar wrote: > Register a dummy release function to avoid the below spew > when the driver is unbinded for an endpoint device. > > root@tegra-ubuntu:/sys/bus/platform/drivers/tegra194-pcie# echo "141a0000.pcie-ep" > unbind > [ 55.802704] ------------[ cut here ]------------ > [ 55.802737] Device '141a0000.pcie-ep' does not have a release() function, it is broken and must be fixed. See Documentation/core-api/kobject.rst. > [ 55.802956] WARNING: CPU: 2 PID: 477 at /home/vidyas/y/mlt/kernel/drivers/base/core.c:2321 device_release+0x7c/0x90 > [ 55.831544] Modules linked in: > [ 55.834781] CPU: 2 PID: 477 Comm: bash Not tainted 5.19.0-rc3-next-20220620-00001-ge53d3cc05d82 #17 > [ 55.844078] Hardware name: NVIDIA Jetson AGX Xavier Developer Kit (DT) > [ 55.850675] pstate: 40400009 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > [ 55.857957] pc : device_release+0x7c/0x90 > [ 55.862265] lr : device_release+0x7c/0x90 > [ 55.866558] sp : ffff80000c24bab0 > [ 55.869965] x29: ffff80000c24bab0 x28: ffff0000872a5700 x27: 0000000000000000 > [ 55.877410] x26: 0000000000000000 x25: 0000000000000000 x24: ffff000080a946bc > [ 55.884840] x23: ffff000080a946c0 x22: 0000000000000000 x21: ffff000083194400 > [ 55.892275] x20: ffff000082076000 x19: ffff00008203ec00 x18: ffffffffffffffff > [ 55.899720] x17: 6620656220747375 x16: 6d20646e61206e65 x15: 62207473756d2064 > [ 55.907179] x14: 6e61206e656b6f72 x13: 6d20646e61206e65 x12: 6b6f726220736920 > [ 55.914651] x11: 2e7473722e746365 x10: 6a626f6b2f697061 x9 : 2d65726f632f6e6f > [ 55.922132] x8 : ffff800009ff2e40 x7 : ffff80000c24b8b0 x6 : 00000000fffff1fc > [ 55.929587] x5 : ffff0003fdf4ba08 x4 : 00000000fffff1fc x3 : ffff8003f44f1000 > [ 55.937033] x2 : ffff0000872a5700 x1 : 45c50f22e593f400 x0 : 0000000000000000 > [ 55.944501] Call trace: > [ 55.947037] device_release+0x7c/0x90 > [ 55.950995] kobject_put+0x90/0x108 > [ 55.954797] device_unregister+0x20/0x30 > [ 55.958877] pci_epc_destroy+0x20/0x38 > [ 55.962908] devm_pci_epc_release+0x10/0x18 > [ 55.967406] release_nodes+0x3c/0x68 > [ 55.971121] devres_release_all+0x8c/0xc8 > [ 55.975409] device_unbind_cleanup+0x14/0x60 > [ 55.979951] device_release_driver_internal+0x100/0x180 > [ 55.985508] device_driver_detach+0x14/0x20 > [ 55.989968] unbind_store+0xd8/0xf0 > [ 55.993732] drv_attr_store+0x20/0x30 > [ 55.997639] sysfs_kf_write+0x48/0x58 > [ 56.001489] kernfs_fop_write_iter+0x118/0x1a0 > [ 56.006239] new_sync_write+0xd0/0x190 > [ 56.010159] vfs_write+0x1bc/0x390 > [ 56.013831] ksys_write+0x64/0xf0 > [ 56.017483] __arm64_sys_write+0x14/0x20 > [ 56.021567] invoke_syscall+0x40/0xf8 > [ 56.025516] el0_svc_common.constprop.3+0x6c/0xf8 > [ 56.030511] do_el0_svc+0x28/0xc8 > [ 56.033920] el0_svc+0x1c/0x58 > [ 56.036936] el0t_64_sync_handler+0x94/0xb8 > [ 56.041049] el0t_64_sync+0x15c/0x160 > [ 56.044652] ---[ end trace 0000000000000000 ]--- > > Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx> There's already a patch posted to fix this. https://lore.kernel.org/all/20220622025031.51812-1-yoshihiro.shimoda.uh@xxxxxxxxxxx/ Regards, Kishon > --- > drivers/pci/endpoint/pci-epc-core.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c > index 3bc9273d0a08..ae403aa54e72 100644 > --- a/drivers/pci/endpoint/pci-epc-core.c > +++ b/drivers/pci/endpoint/pci-epc-core.c > @@ -746,6 +746,11 @@ void devm_pci_epc_destroy(struct device *dev, struct pci_epc *epc) > } > EXPORT_SYMBOL_GPL(devm_pci_epc_destroy); > > +static void pci_epc_nop_release(struct device *dev) > +{ > + dev_vdbg(dev, "%s\n", __func__); > +} > + > /** > * __pci_epc_create() - create a new endpoint controller (EPC) device > * @dev: device that is creating the new EPC > @@ -779,6 +784,7 @@ __pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, > device_initialize(&epc->dev); > epc->dev.class = pci_epc_class; > epc->dev.parent = dev; > + epc->dev.release = pci_epc_nop_release; > epc->ops = ops; > > ret = dev_set_name(&epc->dev, "%s", dev_name(dev));
