[PATCH v2 0/5] PCI: dwc: improve msi handling

Jon Hunter jonathanh at nvidia.com
Fri Sep 25 11:13:02 EDT 2020


Hi Jisheng,

On 25/09/2020 10:27, Jisheng Zhang wrote:

...

>> Could you please try below patch?
>>
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
>> index bf25d783b5c5..7e5dc54d060e 100644
>> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
>> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
>> @@ -197,7 +197,6 @@ static struct irq_chip dw_pci_msi_bottom_irq_chip = {
>>         .name = "DWPCI-MSI",
>>         .irq_ack = dw_pci_bottom_ack,
>>         .irq_compose_msi_msg = dw_pci_setup_msi_msg,
>> -       .irq_set_affinity = dw_pci_msi_set_affinity,
>>         .irq_mask = dw_pci_bottom_mask,
>>         .irq_unmask = dw_pci_bottom_unmask,
>>  };
> 
> A complete patch w/o compiler warning:
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
> index bf25d783b5c5..18f719cfed0b 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
> @@ -137,12 +137,6 @@ static void dw_pci_setup_msi_msg(struct irq_data *d, struct msi_msg *msg)
>  		(int)d->hwirq, msg->address_hi, msg->address_lo);
>  }
>  
> -static int dw_pci_msi_set_affinity(struct irq_data *d,
> -				   const struct cpumask *mask, bool force)
> -{
> -	return -EINVAL;
> -}
> -
>  static void dw_pci_bottom_mask(struct irq_data *d)
>  {
>  	struct pcie_port *pp = irq_data_get_irq_chip_data(d);
> @@ -197,7 +191,6 @@ static struct irq_chip dw_pci_msi_bottom_irq_chip = {
>  	.name = "DWPCI-MSI",
>  	.irq_ack = dw_pci_bottom_ack,
>  	.irq_compose_msi_msg = dw_pci_setup_msi_msg,
> -	.irq_set_affinity = dw_pci_msi_set_affinity,
>  	.irq_mask = dw_pci_bottom_mask,
>  	.irq_unmask = dw_pci_bottom_unmask,
>  };
> 


Thanks I was not expecting this to work because ...

 int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
                         bool force)
 {
         struct irq_desc *desc = irq_data_to_desc(data);
         struct irq_chip *chip = irq_data_get_irq_chip(data);
         int ret;
 
         if (!chip || !chip->irq_set_affinity)
                 return -EINVAL;

However, with your patch Tegra crashes on boot ...

[   11.613853] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[   11.622500] Mem abort info:
[   11.622515]   ESR = 0x86000004
[   11.622524]   EC = 0x21: IABT (current EL), IL = 32 bits
[   11.622540]   SET = 0, FnV = 0
[   11.636544]   EA = 0, S1PTW = 0
[   11.636554] user pgtable: 4k pages, 48-bit VAs, pgdp=000000046a28e000
[   11.636559] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
[   11.652652] Internal error: Oops: 86000004 [#1] PREEMPT SMP
[   11.652658] Modules linked in: pwm_tegra phy_tegra194_p2u crct10dif_ce lm90 pwm_fan tegra_bpmp_thermal pcie_tegra194 ip_tables x_tables ipv6
[   11.670525] CPU: 3 PID: 138 Comm: kworker/3:3 Not tainted 5.9.0-rc4-dirty #12
[   11.670534] Hardware name: NVIDIA Jetson AGX Xavier Developer Kit (DT)
[   11.683967] Workqueue: events deferred_probe_work_func
[   11.683974] pstate: 60c00089 (nZCv daIf +PAN +UAO BTYPE=--)
[   11.683985] pc : 0x0
[   11.696669] lr : msi_domain_set_affinity+0x44/0xc0
[   11.696672] sp : ffff800012bcb390
[   11.696680] x29: ffff800012bcb390 x28: ffff0003e3033c20 
[   11.709891] x27: ffff0003e76cfe58 x26: 0000000000000000 
[   11.709900] x25: ffff800011d7e850 x24: ffff800011d7e878 
[   11.709908] x23: 0000000000000000 x22: ffff0003e76cfe00 
[   11.709914] x21: ffff0003e76cfe58 x20: ffff0003e76cfe58 
[   11.709921] x19: ffff800011b19000 x18: ffffffffffffffff 
[   11.709927] x17: 0000000000000000 x16: 0000000000000000 
[   11.741262] x15: ffff800011b19948 x14: 0000000000000040 
[   11.741267] x13: 0000000000000228 x12: 0000000000000030 
[   11.741272] x11: 0101010101010101 x10: 0000000000000040 
[   11.741277] x9 : 0000000000000000 x8 : 0000000000000004 
[   11.741281] x7 : ffffffffffffffff x6 : 00000000000000ff 
[   11.767374] x5 : 0000000000000000 x4 : 0000000000000000 
[   11.767379] x3 : 0000000000000000 x2 : 0000000000000000 
[   11.767384] x1 : ffff800011d7e898 x0 : ffff0003e262bf00 
[   11.767406] Call trace:
[   11.767410]  0x0
[   11.767424]  irq_do_set_affinity+0x4c/0x178
[   11.791400]  irq_setup_affinity+0x124/0x1b0
[   11.791423]  irq_startup+0x6c/0x118
[   11.791434]  __setup_irq+0x810/0x8a0
[   11.802510]  request_threaded_irq+0xdc/0x188
[   11.802517]  pcie_pme_probe+0x98/0x110
[   11.802536]  pcie_port_probe_service+0x34/0x60
[   11.814799]  really_probe+0x110/0x400
[   11.814809]  driver_probe_device+0x54/0xb8
[   11.822438]  __device_attach_driver+0x90/0xc0
[   11.822463]  bus_for_each_drv+0x70/0xc8
[   11.822471]  __device_attach+0xec/0x150
[   11.834307]  device_initial_probe+0x10/0x18
[   11.834311]  bus_probe_device+0x94/0xa0
[   11.834315]  device_add+0x464/0x730
[   11.834338]  device_register+0x1c/0x28
[   11.834349]  pcie_port_device_register+0x2d0/0x3e8
[   11.854056]  pcie_portdrv_probe+0x34/0xd8
[   11.854063]  local_pci_probe+0x3c/0xa0
[   11.854088]  pci_device_probe+0x128/0x1c8
[   11.854103]  really_probe+0x110/0x400
[   11.869283]  driver_probe_device+0x54/0xb8
[   11.869311]  __device_attach_driver+0x90/0xc0
[   11.877638]  bus_for_each_drv+0x70/0xc8
[   11.877645]  __device_attach+0xec/0x150
[   11.877669]  device_attach+0x10/0x18
[   11.877680]  pci_bus_add_device+0x4c/0xb0
[   11.892642]  pci_bus_add_devices+0x44/0x90
[   11.892646]  dw_pcie_host_init+0x370/0x4f8
[   11.892653]  tegra_pcie_dw_probe+0x5e8/0xb50 [pcie_tegra194]
[   11.892661]  platform_drv_probe+0x50/0xa8
[   11.910179]  really_probe+0x110/0x400
[   11.910183]  driver_probe_device+0x54/0xb8
[   11.910186]  __device_attach_driver+0x90/0xc0
[   11.910213]  bus_for_each_drv+0x70/0xc8
[   11.910240]  __device_attach+0xec/0x150
[   11.929689]  device_initial_probe+0x10/0x18
[   11.929694]  bus_probe_device+0x94/0xa0
[   11.929719]  deferred_probe_work_func+0x6c/0xa0
[   11.929730]  process_one_work+0x1cc/0x360
[   11.946008]  worker_thread+0x48/0x450
[   11.949602]  kthread+0x120/0x150
[   11.952803]  ret_from_fork+0x10/0x1c
[   11.956332] Code: bad PC value
[   11.959360] ---[ end trace 03c30e252fe4e40b ]---

To be honest, I am not sure I completely understand why it crashes here.

Cheers
Jon

-- 
nvpublic



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