On 04/01/2017 03:13 AM, Boszormenyi Zoltan wrote:
2017-03-31 17:05 keltezéssel, Guenter Roeck írta:On Fri, Mar 31, 2017 at 04:46:02PM +0200, Boszormenyi Zoltan wrote:2017-03-31 14:49 keltezéssel, Guenter Roeck írta:request_muxed_region() can fail, and literally every other driver using it checks for that failure. Please do the same.In what circumstances can request_muxed_region() fail? As far as I can see, only if two drivers use the same I/O port base and the already present region did not use IORESOURCE_MUXED which is not the case here. When request_muxed_region() is used consistently, subsequent requests are put on a wait queue and the first one is woken up when the region is released. So, it's basically a mutex. Am I missing something here?Yes. failure to allocate the resource is one.So, a common mutex should be used.
Just because you don't want to check for errors ? I am not on favor of your new solution. I think it violates layering all over the place, and I dislike the idea of having a global mutex as you propose. I won't shut it down, but I'll let others provide feedback on your new series of patches. Guenter
I have also added synchronization to the USB PCI quirks code and have split the patch into three pieces now (USB quirks, i2c-piix4 and sp5100_tco) and they were sent to the relevant mailing lists. I don't know which subsystem wants to take it, all 3 patches are needed at once. Best regards, Zoltán Böszörményi