Problems with uio_pci_generic in v4.18-rc8

Problems with uio_pci_generic in v4.18-rc8

[Harris, James R]

Hi,
 
Using Linux kernel v4.18-rc8, I am unable to bind a PCI device to uio_pci_generic.  This works fine with v4.18-rc4.  dmesg shows:
 
[  336.221585] genirq: Threaded irq requested with handler=NULL and !ONESHOT for irq 33
[  336.221681] uio_pci_generic: probe of 0000:04:00.0 failed with error -22
 
This problem has been reproduced on multiple systems.
 
This seems to be related to commit 9421e45f5 (“uio: use request_threaded_irq instead”) which was merged in -rc5.  Reverting this commit fixes the issue (I also reverted 543af5861f and 57c5f4df0a which also touch uio.c - just to be safe).
 
This seems like a serious regression to uio_pci_generic, but any tips or pointers would be appreciated.
 
Thanks,
 
Jim Harris

Re: Problems with uio_pci_generic in v4.18-rc8

[Xiubo Li]

Hi Harris,

Since the lock protection in uio irq handler is useless currently as 
discussed in the mail list, so I will revert this commit with small 
changes and now the testing based LIO/TCMU has been finished.

Thanks,
BRs


On 2018/8/11 5:12, Harris, James R wrote:
> Hi,
>   
> Using Linux kernel v4.18-rc8, I am unable to bind a PCI device to uio_pci_generic.  This works fine with v4.18-rc4.  dmesg shows:
>   
> [  336.221585] genirq: Threaded irq requested with handler=NULL and !ONESHOT for irq 33
> [  336.221681] uio_pci_generic: probe of 0000:04:00.0 failed with error -22
>   
> This problem has been reproduced on multiple systems.
>   
> This seems to be related to commit 9421e45f5 (“uio: use request_threaded_irq instead”) which was merged in -rc5.  Reverting this commit fixes the issue (I also reverted 543af5861f and 57c5f4df0a which also touch uio.c - just to be safe).
>   
> This seems like a serious regression to uio_pci_generic, but any tips or pointers would be appreciated.
>   
> Thanks,
>   
> Jim Harris
>

Re: Problems with uio_pci_generic in v4.18-rc8

[gregkh]

On Sun, Aug 12, 2018 at 06:55:58PM +0800, Xiubo Li wrote:
> Hi Harris,
> 
> Since the lock protection in uio irq handler is useless currently as
> discussed in the mail list, so I will revert this commit with small changes
> and now the testing based LIO/TCMU has been finished.

Can you send the fixup patch so I can apply it please?

thanks,

greg k-h

Re: Problems with uio_pci_generic in v4.18-rc8

[Xiubo Li]

On 2018/8/12 19:03, gregkh@linuxfoundation.org wrote:
> On Sun, Aug 12, 2018 at 06:55:58PM +0800, Xiubo Li wrote:
>> Hi Harris,
>>
>> Since the lock protection in uio irq handler is useless currently as
>> discussed in the mail list, so I will revert this commit with small changes
>> and now the testing based LIO/TCMU has been finished.
> Can you send the fixup patch so I can apply it please?
Yeah, sure.

Thanks,

> thanks,
>
> greg k-h