On Mon, Jun 19, 2017 at 01:43:21AM +0200, Jarkko Sakkinen wrote: > From: "Hon Ching \\(Vicky\\) Lo" <honclo@xxxxxxxxxxxxxxxxxx> > > The current code passes the address of tpm_chip as the argument to > dev_get_drvdata() without prior NULL check in > tpm_ibmvtpm_get_desired_dma. This resulted an oops during kernel > boot when vTPM is enabled in Power partition configured in active > memory sharing mode. > > The vio_driver's get_desired_dma() is called before the probe(), which > for vtpm is tpm_ibmvtpm_probe, and it's this latter function that > initializes the driver and set data. Attempting to get data before > the probe() caused the problem. > > This patch adds a NULL check to the tpm_ibmvtpm_get_desired_dma. > > fixes: 9e0d39d8a6a0 ("tpm: Remove useless priv field in struct tpm_vendor_specific") > Cc: <stable@xxxxxxxxxxxxxxx> > Signed-off-by: Hon Ching(Vicky) Lo <honclo@xxxxxxxxxxxxxxxxxx> > Reviewed-by: Jarkko Sakkine <jarkko.sakkinen@xxxxxxxxxxxxxxx> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx> > --- > Backport for v4.9. I asked to Vicky to test my backport so this should be OK. Thanks for this, but next time can you give me a hint of what the git commit id is for the patch in Linus's tree? I had to go dig it out by hand :( greg k-h