On Friday, February 22, 2013 3:54 PM, Dmitry Torokhov wrote: > > Hi, > > It looks like a whole slew of devm_request_irq() conversions just got > applied to mainline and many of them are quite broken. > > Consider fd5231ce336e038037b4f0190a6838bdd6e17c6d or > c1879fe80c61f3be6f2ddb82509c2e7f92a484fe: the drivers udsed first to > free IRQ and then unregister the corresponding device ensuring that IRQ > handler, while it runs, has the device available. The mechanic > conversion to devm_request_irq() reverses the order of these operations > opening the race window where IRQ can reference device (or other > resource) that is already gone. > > It would be nice if these could be reverted and revioewed again for > correctness.
Um, other RTC drivers already have been using devm_request_threaded_irq() or devm_request_irq() like this, before I added these patches. For example, ./drivers/rtc/rtc-tegra.c ./drivers/rtc/rtc-spear.c ./drivers/rtc/rtc-s3c.c ./drivers/rtc/rtc-mxc.c ./drivers/rtc/rtc-ds1553.c ./drivers/rtc/rtc-ds1511.c ./drivers/rtc/rtc-snvs.c ./drivers/rtc/rtc-imxdi.c ./drivers/rtc/rtc-tx4939.c ./drivers/rtc/rtc-mv.c ./drivers/rtc/rtc-coh901331.c ./drivers/rtc/rtc-stk17ta8.c ./drivers/rtc/rtc-lpc32xx.c ./drivers/rtc/rtc-tps65910.c ./drivers/rtc/rtc-rc5t583.c Also, even more, some RTC drivers calls rtc_device_unregister() first, then calls free_irq() later. For example, ./drivers/rtc/rtc-vr41xx.c ./drivers/rtc/rtc-da9052.c ./drivers/rtc/rtc-isl1208.c ./drivers/rtc/rtc-88pm860x.c ./drivers/rtc/rtc-tps6586x.c ./drivers/rtc/rtc-mpc5121.c ./drivers/rtc/rtc-m48t59.c Please, don't argue revert without concrete reasons. If these devm_request_threaded_irq() or devm_request_irq() make the problem, devm_free_irq() will be added later. > > In general any conversion to devm_request_irq() needs double and triple > checking. > > Thanks. > > -- > Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
