Messages in this thread | | | From | "Rafael J. Wysocki" <> | Date | Thu, 24 May 2018 17:57:56 +0200 | Subject | Re: [PATCH RFC] suspend: Prevent might sleep splats |
| |
On Thu, May 24, 2018 at 5:45 PM, Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote: > On 2018-05-24 17:07:16 [+0200], Rafael J. Wysocki wrote: >> On Thu, May 24, 2018 at 4:24 PM, Sebastian Andrzej Siewior >> <bigeasy@linutronix.de> wrote: >> > From: Thomas Gleixner <tglx@linutronix.de> >> > >> > timekeeping suspend/resume calls read_persistent_clock() which takes >> > rtc_lock. That results in might sleep warnings because at that point >> > we run with interrupts disabled. >> > >> > We cannot convert rtc_lock to a raw spinlock as that would trigger >> > other might sleep warnings. >> > >> > As a workaround we disable the might sleep warnings by setting >> > system_state to SYSTEM_SUSPEND before calling sysdev_suspend() and >> > restoring it to SYSTEM_RUNNING afer sysdev_resume(). >> > >> > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> >> > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> >> >> Hmm. Don't we also need to cover suspend-to-idle? > > Well, if you agree with the approach then I would look into it.
As long as the SYSTEM_SUSPEND system state is defined unambiguously, I don't have a problem with doing this.
| |