| Message ID | 20230901164111.RFT.13.I0a9940ff6f387d6acf4e71d8c7dbaff8c42e3aaa@changeid (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm: non-drm-misc drivers call drm_atomic_helper_shutdown() at the right times | expand |
On Fri, 1 Sep 2023 16:41:24 -0700, Douglas Anderson wrote: > Based on grepping through the source code this driver appears to be > missing a call to drm_atomic_helper_shutdown() at system shutdown time > and at driver unbind time. Among other things, this means that if a > panel is in use that it won't be cleanly powered off at system > shutdown time. > > [ ... ] Reviewed-by: Maxime Ripard <mripard@kernel.org> Thanks! Maxime
On Fr, 2023-09-01 at 16:41 -0700, Douglas Anderson wrote: > Based on grepping through the source code this driver appears to be > missing a call to drm_atomic_helper_shutdown() at system shutdown time > and at driver unbind time. Among other things, this means that if a > panel is in use that it won't be cleanly powered off at system > shutdown time. > > The fact that we should call drm_atomic_helper_shutdown() in the case > of OS shutdown/restart and at driver remove (or unbind) time comes > straight out of the kernel doc "driver instance overview" in > drm_drv.c. > > A few notes about this fix: > - When adding drm_atomic_helper_shutdown() to the unbind path, I added > it after drm_kms_helper_poll_fini() since that's when other drivers > seemed to have it. > - Technically with a previous patch, ("drm/atomic-helper: > drm_atomic_helper_shutdown(NULL) should be a noop"), we don't > actually need to check to see if our "drm" pointer is NULL before > calling drm_atomic_helper_shutdown(). We'll leave the "if" test in, > though, so that this patch can land without any dependencies. It > could potentially be removed later. > - This patch also makes sure to set the drvdata to NULL in the case of > bind errors to make sure that shutdown can't access freed data. > > Suggested-by: Maxime Ripard <mripard@kernel.org> > Signed-off-by: Douglas Anderson <dianders@chromium.org> Thank you, Tested-by: Philipp Zabel <p.zabel@pengutronix.de> regards Philipp
Hi, On Mon, Sep 4, 2023 at 1:30 AM Philipp Zabel <p.zabel@pengutronix.de> wrote: > > On Fr, 2023-09-01 at 16:41 -0700, Douglas Anderson wrote: > > Based on grepping through the source code this driver appears to be > > missing a call to drm_atomic_helper_shutdown() at system shutdown time > > and at driver unbind time. Among other things, this means that if a > > panel is in use that it won't be cleanly powered off at system > > shutdown time. > > > > The fact that we should call drm_atomic_helper_shutdown() in the case > > of OS shutdown/restart and at driver remove (or unbind) time comes > > straight out of the kernel doc "driver instance overview" in > > drm_drv.c. > > > > A few notes about this fix: > > - When adding drm_atomic_helper_shutdown() to the unbind path, I added > > it after drm_kms_helper_poll_fini() since that's when other drivers > > seemed to have it. > > - Technically with a previous patch, ("drm/atomic-helper: > > drm_atomic_helper_shutdown(NULL) should be a noop"), we don't > > actually need to check to see if our "drm" pointer is NULL before > > calling drm_atomic_helper_shutdown(). We'll leave the "if" test in, > > though, so that this patch can land without any dependencies. It > > could potentially be removed later. > > - This patch also makes sure to set the drvdata to NULL in the case of > > bind errors to make sure that shutdown can't access freed data. > > > > Suggested-by: Maxime Ripard <mripard@kernel.org> > > Signed-off-by: Douglas Anderson <dianders@chromium.org> > > Thank you, > Tested-by: Philipp Zabel <p.zabel@pengutronix.de> Thanks! I notice that: ./scripts/get_maintainer.pl --scm -f drivers/gpu/drm/imx/ipuv3/imx-drm-core.c Doesn't say drm-misc but also when I look at the MAINTAINERS file and find the section for "DRM DRIVERS FOR FREESCALE IMX" it doesn't explicitly list a different git tree. I guess the "shawnguo" git tree listed by get_maintainer.pl is just from regex matching? Would you expect this to go through drm-misc? If so, I'll probably land it sooner rather than later. I can also post up a patch making it obvious that "DRM DRIVERS FOR FREESCALE IMX" goes through drm-misc if you don't object. Thanks! -Doug
Hi, On Di, 2023-09-05 at 13:29 -0700, Doug Anderson wrote: > Hi, > > On Mon, Sep 4, 2023 at 1:30 AM Philipp Zabel <p.zabel@pengutronix.de> wrote: > > > > On Fr, 2023-09-01 at 16:41 -0700, Douglas Anderson wrote: > > > Based on grepping through the source code this driver appears to be > > > missing a call to drm_atomic_helper_shutdown() at system shutdown time > > > and at driver unbind time. Among other things, this means that if a > > > panel is in use that it won't be cleanly powered off at system > > > shutdown time. > > > > > > The fact that we should call drm_atomic_helper_shutdown() in the case > > > of OS shutdown/restart and at driver remove (or unbind) time comes > > > straight out of the kernel doc "driver instance overview" in > > > drm_drv.c. > > > > > > A few notes about this fix: > > > - When adding drm_atomic_helper_shutdown() to the unbind path, I added > > > it after drm_kms_helper_poll_fini() since that's when other drivers > > > seemed to have it. > > > - Technically with a previous patch, ("drm/atomic-helper: > > > drm_atomic_helper_shutdown(NULL) should be a noop"), we don't > > > actually need to check to see if our "drm" pointer is NULL before > > > calling drm_atomic_helper_shutdown(). We'll leave the "if" test in, > > > though, so that this patch can land without any dependencies. It > > > could potentially be removed later. > > > - This patch also makes sure to set the drvdata to NULL in the case of > > > bind errors to make sure that shutdown can't access freed data. > > > > > > Suggested-by: Maxime Ripard <mripard@kernel.org> > > > Signed-off-by: Douglas Anderson <dianders@chromium.org> > > > > Thank you, > > Tested-by: Philipp Zabel <p.zabel@pengutronix.de> > > Thanks! I notice that: > > ./scripts/get_maintainer.pl --scm -f drivers/gpu/drm/imx/ipuv3/imx-drm-core.c > > Doesn't say drm-misc but also when I look at the MAINTAINERS file and > find the section for "DRM DRIVERS FOR FREESCALE IMX" That should probably say "IMX5/6" nowadays. There are a lot more i.MX that do not use IPUv3 than those that do. > it doesn't explicitly list a different git tree. I used to send pull requests from git.pengutronix.de/git/pza/linux, same as for the reset controller framework. I might still have to do that for changes in drivers/gpu/ipu-v3 that need coordination between drm and v4l2, but usually pure drm/imx/ipuv3 changes are pushed to drm- misc. > I guess the "shawnguo" git tree listed by get_maintainer.pl is just > from regex matching? The "N: imx" pattern in "ARM/FREESCALE IMX / MXC ARM ARCHITECTURE", I think. > Would you expect this to go through drm-misc? If so, I'll probably > land it sooner rather than later. I can also post up a patch making it > obvious that "DRM DRIVERS FOR FREESCALE IMX" goes through drm-misc if > you don't object. Yes, both would be great. regards Philipp
Hi, On Tue, Sep 5, 2023 at 10:47 PM Philipp Zabel <p.zabel@pengutronix.de> wrote: > > Hi, > > On Di, 2023-09-05 at 13:29 -0700, Doug Anderson wrote: > > Hi, > > > > On Mon, Sep 4, 2023 at 1:30 AM Philipp Zabel <p.zabel@pengutronix.de> wrote: > > > > > > On Fr, 2023-09-01 at 16:41 -0700, Douglas Anderson wrote: > > > > Based on grepping through the source code this driver appears to be > > > > missing a call to drm_atomic_helper_shutdown() at system shutdown time > > > > and at driver unbind time. Among other things, this means that if a > > > > panel is in use that it won't be cleanly powered off at system > > > > shutdown time. > > > > > > > > The fact that we should call drm_atomic_helper_shutdown() in the case > > > > of OS shutdown/restart and at driver remove (or unbind) time comes > > > > straight out of the kernel doc "driver instance overview" in > > > > drm_drv.c. > > > > > > > > A few notes about this fix: > > > > - When adding drm_atomic_helper_shutdown() to the unbind path, I added > > > > it after drm_kms_helper_poll_fini() since that's when other drivers > > > > seemed to have it. > > > > - Technically with a previous patch, ("drm/atomic-helper: > > > > drm_atomic_helper_shutdown(NULL) should be a noop"), we don't > > > > actually need to check to see if our "drm" pointer is NULL before > > > > calling drm_atomic_helper_shutdown(). We'll leave the "if" test in, > > > > though, so that this patch can land without any dependencies. It > > > > could potentially be removed later. > > > > - This patch also makes sure to set the drvdata to NULL in the case of > > > > bind errors to make sure that shutdown can't access freed data. > > > > > > > > Suggested-by: Maxime Ripard <mripard@kernel.org> > > > > Signed-off-by: Douglas Anderson <dianders@chromium.org> > > > > > > Thank you, > > > Tested-by: Philipp Zabel <p.zabel@pengutronix.de> > > > > Thanks! I notice that: > > > > ./scripts/get_maintainer.pl --scm -f drivers/gpu/drm/imx/ipuv3/imx-drm-core.c > > > > Doesn't say drm-misc but also when I look at the MAINTAINERS file and > > find the section for "DRM DRIVERS FOR FREESCALE IMX" > > That should probably say "IMX5/6" nowadays. There are a lot more i.MX > that do not use IPUv3 than those that do. > > > it doesn't explicitly list a different git tree. > > I used to send pull requests from git.pengutronix.de/git/pza/linux, > same as for the reset controller framework. I might still have to do > that for changes in drivers/gpu/ipu-v3 that need coordination between > drm and v4l2, but usually pure drm/imx/ipuv3 changes are pushed to drm- > misc. > > > I guess the "shawnguo" git tree listed by get_maintainer.pl is just > > from regex matching? > > The "N: imx" pattern in "ARM/FREESCALE IMX / MXC ARM ARCHITECTURE", I > think. > > > Would you expect this to go through drm-misc? If so, I'll probably > > land it sooner rather than later. I can also post up a patch making it > > obvious that "DRM DRIVERS FOR FREESCALE IMX" goes through drm-misc if > > you don't object. > > Yes, both would be great. Maintainers update posted at: https://lore.kernel.org/r/20230906072803.1.Idef7e77e8961cbeb8625183eec9db0356b2eccd0@changeid I'll aim to land ${SUBJECT} patch early next week unless there are any objections. -Doug
Hi, On Fri, Sep 1, 2023 at 4:42 PM Douglas Anderson <dianders@chromium.org> wrote: > > Based on grepping through the source code this driver appears to be > missing a call to drm_atomic_helper_shutdown() at system shutdown time > and at driver unbind time. Among other things, this means that if a > panel is in use that it won't be cleanly powered off at system > shutdown time. > > The fact that we should call drm_atomic_helper_shutdown() in the case > of OS shutdown/restart and at driver remove (or unbind) time comes > straight out of the kernel doc "driver instance overview" in > drm_drv.c. > > A few notes about this fix: > - When adding drm_atomic_helper_shutdown() to the unbind path, I added > it after drm_kms_helper_poll_fini() since that's when other drivers > seemed to have it. > - Technically with a previous patch, ("drm/atomic-helper: > drm_atomic_helper_shutdown(NULL) should be a noop"), we don't > actually need to check to see if our "drm" pointer is NULL before > calling drm_atomic_helper_shutdown(). We'll leave the "if" test in, > though, so that this patch can land without any dependencies. It > could potentially be removed later. > - This patch also makes sure to set the drvdata to NULL in the case of > bind errors to make sure that shutdown can't access freed data. > > Suggested-by: Maxime Ripard <mripard@kernel.org> > Signed-off-by: Douglas Anderson <dianders@chromium.org> > --- > This commit is only compile-time tested. > > drivers/gpu/drm/imx/ipuv3/imx-drm-core.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c b/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c > index 4a866ac60fff..4c8bc49758a7 100644 > --- a/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c > +++ b/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c > @@ -257,6 +257,7 @@ static int imx_drm_bind(struct device *dev) > drm_kms_helper_poll_fini(drm); > component_unbind_all(drm->dev, drm); > err_kms: > + dev_set_drvdata(dev, NULL); > drm_dev_put(drm); > > return ret; > @@ -269,6 +270,7 @@ static void imx_drm_unbind(struct device *dev) > drm_dev_unregister(drm); > > drm_kms_helper_poll_fini(drm); > + drm_atomic_helper_shutdown(drm); > > component_unbind_all(drm->dev, drm); > > @@ -298,6 +300,14 @@ static int imx_drm_platform_remove(struct platform_device *pdev) > return 0; > } > > +static void imx_drm_platform_shutdown(struct platform_device *pdev) > +{ > + struct drm_device *drm = platform_get_drvdata(pdev); > + > + if (drm) > + drm_atomic_helper_shutdown(platform_get_drvdata(pdev)); Since this is now landing through the drm-misc-next tree, I got rid of the check for NULL when applying and landed this after the patch ("drm/atomic-helper: drm_atomic_helper_shutdown(NULL) should be a noop"). > @@ -325,6 +335,7 @@ MODULE_DEVICE_TABLE(of, imx_drm_dt_ids); > static struct platform_driver imx_drm_pdrv = { > .probe = imx_drm_platform_probe, > .remove = imx_drm_platform_remove, > + .shutdown = imx_drm_platform_shutdown, There was a trivial context conflict with commit 3095f1122203 ("drm/imx/ipuv3: Convert to platform remove callback returning void") that I resolved while applying. I've now pushed to drm-misc-next: 02680d71dea8 drm/imx/ipuv3: Call drm_atomic_helper_shutdown() at shutdown/unbind time
diff --git a/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c b/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c index 4a866ac60fff..4c8bc49758a7 100644 --- a/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c +++ b/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c @@ -257,6 +257,7 @@ static int imx_drm_bind(struct device *dev) drm_kms_helper_poll_fini(drm); component_unbind_all(drm->dev, drm); err_kms: + dev_set_drvdata(dev, NULL); drm_dev_put(drm); return ret; @@ -269,6 +270,7 @@ static void imx_drm_unbind(struct device *dev) drm_dev_unregister(drm); drm_kms_helper_poll_fini(drm); + drm_atomic_helper_shutdown(drm); component_unbind_all(drm->dev, drm); @@ -298,6 +300,14 @@ static int imx_drm_platform_remove(struct platform_device *pdev) return 0; } +static void imx_drm_platform_shutdown(struct platform_device *pdev) +{ + struct drm_device *drm = platform_get_drvdata(pdev); + + if (drm) + drm_atomic_helper_shutdown(platform_get_drvdata(pdev)); +} + #ifdef CONFIG_PM_SLEEP static int imx_drm_suspend(struct device *dev) { @@ -325,6 +335,7 @@ MODULE_DEVICE_TABLE(of, imx_drm_dt_ids); static struct platform_driver imx_drm_pdrv = { .probe = imx_drm_platform_probe, .remove = imx_drm_platform_remove, + .shutdown = imx_drm_platform_shutdown, .driver = { .name = "imx-drm", .pm = &imx_drm_pm_ops,
Based on grepping through the source code this driver appears to be missing a call to drm_atomic_helper_shutdown() at system shutdown time and at driver unbind time. Among other things, this means that if a panel is in use that it won't be cleanly powered off at system shutdown time. The fact that we should call drm_atomic_helper_shutdown() in the case of OS shutdown/restart and at driver remove (or unbind) time comes straight out of the kernel doc "driver instance overview" in drm_drv.c. A few notes about this fix: - When adding drm_atomic_helper_shutdown() to the unbind path, I added it after drm_kms_helper_poll_fini() since that's when other drivers seemed to have it. - Technically with a previous patch, ("drm/atomic-helper: drm_atomic_helper_shutdown(NULL) should be a noop"), we don't actually need to check to see if our "drm" pointer is NULL before calling drm_atomic_helper_shutdown(). We'll leave the "if" test in, though, so that this patch can land without any dependencies. It could potentially be removed later. - This patch also makes sure to set the drvdata to NULL in the case of bind errors to make sure that shutdown can't access freed data. Suggested-by: Maxime Ripard <mripard@kernel.org> Signed-off-by: Douglas Anderson <dianders@chromium.org> --- This commit is only compile-time tested. drivers/gpu/drm/imx/ipuv3/imx-drm-core.c | 11 +++++++++++ 1 file changed, 11 insertions(+)