On Wed, Apr 24, 2019 at 06:16:32PM +0200, Wolfram Sang wrote: > There are two problems with dev_err() here. One: It is not ratelimited. > Two: We don't see which driver tried to transfer something with a > suspended adapter. Switch to dev_WARN_ONCE to fix both issues. Drawback > is that we don't see if multiple drivers are trying to transfer while > suspended. They need to be discovered one after the other now. This is > better than a high CPU load because a really broken driver might try to > resend endlessly. >
Reviewed-by: Andy Shevchenko <[email protected]> > Link: https://bugs.archlinux.org/task/62391 > Fixes: 275154155538 ("i2c: designware: Do not allow i2c_dw_xfer() calls while > suspended") > Signed-off-by: Wolfram Sang <[email protected]> > --- > > skdnik: Would you be so kind and test this patch? I can only build-test here. > > I have a prototype to fix the similar issue in the core, but this needs more > testing first, so I am sending this one out already. > > drivers/i2c/busses/i2c-designware-master.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-designware-master.c > b/drivers/i2c/busses/i2c-designware-master.c > index bb8e3f149979..d464799e40a3 100644 > --- a/drivers/i2c/busses/i2c-designware-master.c > +++ b/drivers/i2c/busses/i2c-designware-master.c > @@ -426,8 +426,7 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg > msgs[], int num) > > pm_runtime_get_sync(dev->dev); > > - if (dev->suspended) { > - dev_err(dev->dev, "Error %s call while suspended\n", __func__); > + if (dev_WARN_ONCE(dev->dev, dev->suspended, "Transfer while > suspended\n")) { > ret = -ESHUTDOWN; > goto done_nolock; > } > -- > 2.11.0 > -- With Best Regards, Andy Shevchenko
