> From: Anson Huang > Sent: Wednesday, July 17, 2019 9:58 PM> > Hi, Aisheng > > > > From: Anson.Huang@xxxxxxx <Anson.Huang@xxxxxxx> > > > Sent: Tuesday, July 16, 2019 3:19 PM > > > > > > The RTC IRQ is requested before the struct rtc_device is allocated, > > > this may lead to a NULL pointer dereference in IRQ handler. > > > > > > To fix this issue, allocating the rtc_device struct before > > > requesting the RTC IRQ using devm_rtc_allocate_device, and use > > > rtc_register_device to register the RTC device. > > > > > > > I saw other rtc drivers did the same way as us, so this looks like a > > common problem. > > My question is if we can clear interrupt status before register to > > avoid this issue as other rtc drivers? > > I think we can NOT predict when the IRQ will be pending, IRQ could arrive at > any time, the most safe way is to prepare everything before > requesting/enabling IRQ. > There is also patch to fix similar issue: > I just feel like it's common issue. But seems community already did the same thing. So: Reviewed-by: Dong Aisheng <aisheng.dong@xxxxxxx> Regards Aisheng > commit 060711f5274dfc2d76a5b2cd65abf6ccbf061e40 > Author: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx> > Date: Tue Apr 30 11:32:09 2019 +0200 > > rtc: digicolor: fix possible race condition > > Anson
