On 12/10/21 10:30 PM, Sergey Shtylyov wrote: [...] >>>>>>>>>>> platform_get_irq() will print a message when it fails. >>>>>>>>>>> No need to repeat this. >>>>>>>>>>> >>>>>>>>>>> While at it, drop redundant check for 0 as platform_get_irq() spills >>>>>>>>>>> out a big WARN() in such case. >>>>>>>>>> >>>>>>>>>> The reason you should be able to remove the "if (!irq)" test is that >>>>>>>>>> platform_get_irq() never returns 0. At least, that is what the function kdoc >>>>>>>>>> says. But looking at platform_get_irq_optional(), which is called by >>>>>>>>>> platform_get_irq(), the out label is: >>>>>>>>>> >>>>>>>>>> WARN(ret == 0, "0 is an invalid IRQ number\n"); >>>>>>>>>> return ret; >>>>>>>>>> >>>>>>>>>> So 0 will be returned as-is. That is rather weird. That should be fixed to >>>>>>>>>> return -ENXIO: >>>>>>>>>> >>>>>>>>>> if (WARN(ret == 0, "0 is an invalid IRQ number\n")) >>>>>>>>>> return -ENXIO; >>>>>>>>>> return ret; >>>>>>>>> >>>>>>>>> My unmerged patch (https://marc.info/?l=linux-kernel&m=163623041902285) does this >>>>>>>>> but returns -EINVAL instead. >>>>>>>>> >>>>>>>>>> Otherwise, I do not think that removing the "if (!irq)" hunk is safe. no ? >>>>>>>>> >>>>>>>>> Of course it isn't... >>>>>>>> >>>>>>>> It's unsubstantiated statement. The vIRQ 0 shouldn't be returned by any of >>>>>>>> those API calls. >>>>>>> >>>>>>> We do _not_ know what needs to be fixed, that's the problem, and that's why the WARN() >>>>>>> is there... >>>>>> >>>>>> So, have you seen this warning (being reported) related to libahci_platform? >>>>> >>>>> No (as if you need to really see this while it's obvious from the code review). >>>>> >>>>>> If no, what we are discussing about then? The workaround is redundant and >>>>> >>>>> I don't know. :-) Your arguments so far seem bogus (sorry! :-))... >>>> >>>> It seems you haven't got them at all. The problems of platform_get_irq() et al >>>> shouldn't be worked around in the callers. >>> >>> I have clearly explained to you what I'm working around there. If that wasn't clear >>> enough, I don't want to continue this talk anymore. Good luck with your patch (not this >>> one). >> >> Good luck with yours, not the one that touches platform_get_irq_optional() though! > > Mmh, I'm not touching it any way that would break what your patch was trying to do, > unless you've re-thopught that. It also shoudn't matter whose patch gets merged 1st > other than some small adaptation). BTW, looking at [1], this comment is wrong: + * Return: non-zero IRQ number on success, negative error number on failure. It doesn't mention 0 which you return from this function. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ed7027fdf4ec41ed6df6814956dc11860232a9d5 MBR, Sergey
