Re: Regression in inv_mpu6050: 4.6.0-rc5

Greg KH
2016-05-04T17:24:46Z

On Wed, May 04, 2016 at 08:49:06AM +0100, Jonathan Cameron wrote:
> On 03/05/16 19:54, Crestez Dan Leonard wrote:
> > On 05/01/2016 10:58 PM, Jonathan Cameron wrote:
> >> On 27/04/16 16:56, One Thousand Gnomes wrote:
> >>> On Tue, 26 Apr 2016 18:07:55 -0500
> >>> Michael Welling <mwelling@ieee.org> wrote:
> >>>
> >>>> On Tue, Apr 26, 2016 at 11:26:51PM +0100, One Thousand Gnomes wrote:
> >>>>>
> >>>>> This now causes us to crash and burn on the ASUS T100TA Baytrail/T
> >>>>> platforms
> >>>>>
> >>>>
> >>>> I believe this regression has already been patched.
> >>>>
> >>>> Check the latest commits in linux-next.
> >>>>
> >>>> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/log/drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c
> >>>>
> >>>> See if the latest patches fix your issue.
> >>>
> >>> It does - as this is a regression can we please get those fixes into the
> >>> next -rc ?
> >>>
> >> I'm afraid I'm lost in this one - which patch caused the regression and
> >> which one fixed it? The only patches I can immediately see in next
> >> both introduce and then squish a similar bug, but neither of them
> >> has hit Linus' tree yet.
> >>
> >> Or are we dealing with what was fixed in:
> >> c816d9e7 iio: imu: mpu6050: fix possible NULL dereferences
> >> I had understood that one as more hypothetical than real...
> >>
> >> Unfortunately I'm travelling and I suspect that means this will only get
> >> in just after the release (so for 4.6.1) once I've confirmed which fixes
> >> we actually need to backport.
> >>
> > Commit
> > c816d9e7: iio: imu: mpu6050: fix possible NULL dereferences
> > Fixes:
> > 33da559f: iio: imu: mpu6050: add mpu6500 register settings
> >
> > As far as I can tell this crash will always happen when the device is
> > probed via ACPI.
>
> Hi Greg,
>
> A quick heads up.
>
> Unfortunately this regression has come up whilst I'm travelling and
> don't have appropriate signing keys with me to do a pull request.
> Should be able to do one tomorrow evening as I'll back home.
>
> Turns out the 'possible' is quite common and causing a mess.
> Even better the fix actually has a fix as well...
>
> Fastest option is probably a cherry pick of:
>
> c816d9e7: iio: imu: mpu6050: fix possible NULL dereferences
> 718ba46e: iio: imu: mpu6050: Fix name/chip_id when using ACPI

>From where?

>
> I'll send you a pull request of my
> togreg-in-a-hurry branch tomorrow.
>
> Sorry for these being so late in the cycle.
>
> Anyhow, run for train time.

You can always just send me patches, no need for it to always be a pull
request if you can't do that for some reason.

thanks,

greg k-h