Re: [PATCH] soc: fsl: dpio: register dpio irq handlers after dpio create

[Laurentiu Tudor]

On 10.03.2020 22:30, Li Yang wrote:
> On Tue, Mar 10, 2020 at 7:09 AM Laurentiu Tudor <laurentiu.tudor@xxxxxxx> wrote:
> > From: Grigore Popescu <grigore.popescu@xxxxxxx>
> >
> > 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>
>
> Applied for fix.  Thanks.  Does this fix apply to stable kernels?

It sure does, good point.

---
Best Regards, Laurentiu

> > ---
> >   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 70014ecce2a7..7b642c330977 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);
> > --
> > 2.17.1