From: Grigore Popescu <grigore.popescu@xxxxxxx> [ Upstream commit fe8fe7723a3a824790bda681b40efd767e2251a7 ] The dpio irqs must be registered when you can actually receive interrupts, ie when the dpios are created. Kernel goes through NULL pointer dereference errors followed by kernel panic [1] because the dpio irqs are enabled before the dpio is created. [1] Unable to handle kernel NULL pointer dereference at virtual address 0040 fsl_mc_dpio dpio.14: probed fsl_mc_dpio dpio.13: Adding to iommu group 11 ISV = 0, ISS = 0x00000004 Unable to handle kernel NULL pointer dereference at virtual address 0040 Mem abort info: ESR = 0x96000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 [0000000000000040] user address but active_mm is swapper Internal error: Oops: 96000004 [#1] PREEMPT SMP Modules linked in: CPU: 2 PID: 151 Comm: kworker/2:1 Not tainted 5.6.0-rc4-next-20200304 #1 Hardware name: NXP Layerscape LX2160ARDB (DT) Workqueue: events deferred_probe_work_func pstate: 00000085 (nzcv daIf -PAN -UAO) pc : dpaa2_io_irq+0x18/0xe0 lr : dpio_irq_handler+0x1c/0x28 sp : ffff800010013e20 x29: ffff800010013e20 x28: ffff0026d9b4c140 x27: ffffa1d38a142018 x26: ffff0026d2953400 x25: ffffa1d38a142018 x24: ffffa1d38a7ba1d8 x23: ffff800010013f24 x22: 0000000000000000 x21: 0000000000000072 x20: ffff0026d2953400 x19: ffff0026d2a68b80 x18: 0000000000000001 x17: 000000002fb37f3d x16: 0000000035eafadd x15: ffff0026d9b4c5b8 x14: ffffffffffffffff x13: ff00000000000000 x12: 0000000000000038 x11: 0101010101010101 x10: 0000000000000040 x9 : ffffa1d388db11e4 x8 : ffffa1d38a7e40f0 x7 : ffff0026da414f38 x6 : 0000000000000000 x5 : ffff0026da414d80 x4 : ffff5e5353d0c000 x3 : ffff800010013f60 x2 : ffffa1d388db11c8 x1 : ffff0026d2a67c00 x0 : 0000000000000000 Call trace: dpaa2_io_irq+0x18/0xe0 dpio_irq_handler+0x1c/0x28 __handle_irq_event_percpu+0x78/0x2c0 handle_irq_event_percpu+0x38/0x90 handle_irq_event+0x4c/0xd0 handle_fasteoi_irq+0xbc/0x168 generic_handle_irq+0x2c/0x40 __handle_domain_irq+0x68/0xc0 gic_handle_irq+0x64/0x150 el1_irq+0xb8/0x180 _raw_spin_unlock_irqrestore+0x14/0x48 irq_set_affinity_hint+0x6c/0xa0 dpaa2_dpio_probe+0x2a4/0x518 fsl_mc_driver_probe+0x28/0x70 really_probe+0xdc/0x320 driver_probe_device+0x5c/0xf0 __device_attach_driver+0x88/0xc0 bus_for_each_drv+0x7c/0xc8 __device_attach+0xe4/0x140 device_initial_probe+0x18/0x20 bus_probe_device+0x98/0xa0 device_add+0x41c/0x758 fsl_mc_device_add+0x184/0x530 dprc_scan_objects+0x280/0x370 dprc_probe+0x124/0x3b0 fsl_mc_driver_probe+0x28/0x70 really_probe+0xdc/0x320 driver_probe_device+0x5c/0xf0 __device_attach_driver+0x88/0xc0 bus_for_each_drv+0x7c/0xc8 __device_attach+0xe4/0x140 device_initial_probe+0x18/0x20 bus_probe_device+0x98/0xa0 deferred_probe_work_func+0x74/0xa8 process_one_work+0x1c8/0x470 worker_thread+0x1f8/0x428 kthread+0x124/0x128 ret_from_fork+0x10/0x18 Code: a9bc7bfd 910003fd a9025bf5 a90363f7 (f9402015) ---[ end trace 38298e1a29e7a570 ]--- Kernel panic - not syncing: Fatal exception in interrupt SMP: stopping secondary CPUs Mem abort info: ESR = 0x96000004 CM = 0, WnR = 0 EC = 0x25: DABT (current EL), IL = 32 bits [0000000000000040] user address but active_mm is swapper SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 [0000000000000040] user address but active_mm is swapper SMP: failed to stop secondary CPUs 0-2 Kernel Offset: 0x21d378600000 from 0xffff800010000000 PHYS_OFFSET: 0xffffe92180000000 CPU features: 0x10002,21806008 Memory Limit: none ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]--- Signed-off-by: Laurentiu Tudor <laurentiu.tudor@xxxxxxx> Signed-off-by: Grigore Popescu <grigore.popescu@xxxxxxx> Signed-off-by: Li Yang <leoyang.li@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/soc/fsl/dpio/dpio-driver.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/soc/fsl/dpio/dpio-driver.c b/drivers/soc/fsl/dpio/dpio-driver.c index 70014ecce2a7e..7b642c330977f 100644 --- a/drivers/soc/fsl/dpio/dpio-driver.c +++ b/drivers/soc/fsl/dpio/dpio-driver.c @@ -233,10 +233,6 @@ static int dpaa2_dpio_probe(struct fsl_mc_device *dpio_dev) goto err_allocate_irqs; } - err = register_dpio_irq_handlers(dpio_dev, desc.cpu); - if (err) - goto err_register_dpio_irq; - priv->io = dpaa2_io_create(&desc, dev); if (!priv->io) { dev_err(dev, "dpaa2_io_create failed\n"); @@ -244,6 +240,10 @@ static int dpaa2_dpio_probe(struct fsl_mc_device *dpio_dev) goto err_dpaa2_io_create; } + err = register_dpio_irq_handlers(dpio_dev, desc.cpu); + if (err) + goto err_register_dpio_irq; + dev_info(dev, "probed\n"); dev_dbg(dev, " receives_notifications = %d\n", desc.receives_notifications); -- 2.20.1