From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Chrisanthus, Anitha" Date: Fri, 20 Nov 2020 22:15:57 +0000 Subject: RE: [PATCH v2] drm/kmb: Fix possible oops in probe error handling Message-Id: List-Id: References: <20201117072103.GA1111239@mwanda> <20201120081113.GL18329@kadam> In-Reply-To: <20201120081113.GL18329@kadam> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Dan Carpenter Cc: David Airlie , "Dea, Edmund J" , "kernel-janitors@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , Sam Ravnborg Hi Dan, I see the problem now, thanks for the patch. > -----Original Message----- > From: Dan Carpenter > Sent: Friday, November 20, 2020 12:11 AM > To: Chrisanthus, Anitha > Cc: Dea, Edmund J ; David Airlie ; > Daniel Vetter ; Sam Ravnborg ; dri- > devel@lists.freedesktop.org; kernel-janitors@vger.kernel.org > Subject: [PATCH v2] drm/kmb: Fix possible oops in probe error handling > > If kmb_dsi_init() fails the "kmb->kmb_dsi" variable is an error pointer. > The kernel will Oops when we pass it to kmb_dsi_host_unregister(). > > Fixes: 7f7b96a8a0a1 ("drm/kmb: Add support for KeemBay Display") > Signed-off-by: Dan Carpenter > --- > v2: write a better commit message > > drivers/gpu/drm/kmb/kmb_drv.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/kmb/kmb_drv.c > b/drivers/gpu/drm/kmb/kmb_drv.c > index a31a840ce634..8c43b136765c 100644 > --- a/drivers/gpu/drm/kmb/kmb_drv.c > +++ b/drivers/gpu/drm/kmb/kmb_drv.c > @@ -504,7 +504,7 @@ static int kmb_probe(struct platform_device *pdev) > if (IS_ERR(kmb->kmb_dsi)) { > drm_err(&kmb->drm, "failed to initialize DSI\n"); > ret = PTR_ERR(kmb->kmb_dsi); > - goto err_free1; > + goto err_clear_drvdata; > } > > kmb->kmb_dsi->dev = &dsi_pdev->dev; > @@ -540,8 +540,9 @@ static int kmb_probe(struct platform_device *pdev) > drm_crtc_cleanup(&kmb->crtc); > drm_mode_config_cleanup(&kmb->drm); > err_free1: > - dev_set_drvdata(dev, NULL); > kmb_dsi_host_unregister(kmb->kmb_dsi); > + err_clear_drvdata: We still need to unregister the dsi_host that was registered in this call kmb_dsi_host_bridge_init. This will require more changes in kmb_dsi_host_unregister and/or separate out mipi_dsi_host_unregister. FYI - I will be out all of next week, will be back the next Monday. > + dev_set_drvdata(dev, NULL); > > return ret; > } > -- > 2.28.0