On Fri, Jun 04, 2021 at 04:27:44PM -0700, Stephen Boyd wrote: > From: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> > > If an i2c client receives an interrupt during reboot or shutdown it may > be too late to service it by making an i2c transaction on the bus > because the i2c controller has already been shutdown. This can lead to > system hangs if the i2c controller tries to make a transfer that is > doomed to fail because the access to the i2c pins is already shut down, > or an iommu translation has been torn down so i2c controller register > access doesn't work. > > Let's simply disable the irq if there isn't a shutdown callback for an > i2c client when there is an irq associated with the device. This will > make sure that irqs don't come in later than the time that we can handle > it. We don't do this if the i2c client device already has a shutdown > callback because presumably they're doing the right thing and quieting > the device so irqs don't come in after the shutdown callback returns. > > Cc: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> > Reported-by: kernel test robot <lkp@xxxxxxxxx> > [swboyd@xxxxxxxxxxxx: Dropped newline, added commit text, added > interrupt.h for robot build error] > Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx> I think this is for-current material because it fixes hangs. Or better for-next to check for side-effects?
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