2016-04-19 11:36 GMT+09:00 Qianyu Gong <qianyu.g...@nxp.com>: > >> -----Original Message----- >> From: Akinobu Mita [mailto:akinobu.m...@gmail.com] >> Sent: Monday, April 18, 2016 9:02 PM >> To: Qianyu Gong <qianyu.g...@nxp.com> >> Cc: alexandre.bell...@free-electrons.com; Mingkai Hu <mingkai...@nxp.com>; >> rtc-li...@googlegroups.com; linux-kernel@vger.kernel.org >> Subject: Re: rtc ds3232 call trace in kernel >> >> 2016-04-18 15:15 GMT+09:00 Qianyu Gong <qianyu.g...@nxp.com>: >> > Hi Akinobu, >> > >> > >> > >> > I got an rtc call trace when booting 4.6 kernel on our board and I >> > found it >> > >> > was caused by this patch: >> > >> > >> > >> > commit fc1dcb0b39dbb10d3290f2fcd6e154670f699166 >> > >> > Author: Akinobu Mita <akinobu.m...@gmail.com> >> > >> > Date: Mon Mar 7 00:27:53 2016 +0900 >> > >> > >> > >> > rtc: ds3232: use rtc->ops_lock to protect alarm operations >> > >> > >> > >> > ds3232->mutex is used to protect for alarm operations which >> > >> > need to access status and control registers. >> > >> > >> > >> > But we can use rtc->ops_lock instead. rtc->ops_lock is held when >> > most >> > >> > of rtc_class_ops methods are called, so we only need to explicitly >> > >> > acquire it from irq handler in order to protect form concurrent >> > >> > accesses. >> > >> > >> > >> > Signed-off-by: Akinobu Mita <akinobu.m...@gmail.com> >> > >> > Signed-off-by: Alexandre Belloni <alexandre.bell...@free-electrons.com >> > >> > >> > >> > The problem is that rtc->ops_lock would be accessed in ds3232_irq() >> > >> > without being initialized as rtc_device_register() is called too late. >> >> You have already identified the root cause of this issue. >> >> > As I’m not familiar with rtc things, could I just revert the patch or >> > you already >> > >> > have a solution to this problem? Thanks in advance. >> >> Could you check if the problem is resolved by moving the call of >> devm_rtc_device_register() from the end of ds3232_probe() to just before >> registering irq handler? > > Yes. It works(no call trace now).
Thanks for testing. Do you mind submitting your patch to rtc-li...@googlegroups.com ?
