| Message ID | 20180807203914.2192-11-lyude@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix connector probing deadlocks from RPM bugs | expand |
Reviewed-by: Karol Herbst <kherbst@redhat.com> On Tue, Aug 7, 2018 at 10:39 PM, Lyude Paul <lyude@redhat.com> wrote: > It's true we can't resume the device from poll workers in > nouveau_connector_detect(). We can however, prevent the autosuspend > timer from elapsing immediately if it hasn't already without risking any > sort of deadlock with the runtime suspend/resume operations. So do that > instead of entirely avoiding grabbing a power reference. > > Signed-off-by: Lyude Paul <lyude@redhat.com> > Cc: stable@vger.kernel.org > Cc: Lukas Wunner <lukas@wunner.de> > Cc: Karol Herbst <karolherbst@gmail.com> > --- > drivers/gpu/drm/nouveau/nouveau_connector.c | 20 +++++++++++--------- > 1 file changed, 11 insertions(+), 9 deletions(-) > > diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c > index 2a45b4c2ceb0..010d6db14cba 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_connector.c > +++ b/drivers/gpu/drm/nouveau/nouveau_connector.c > @@ -572,12 +572,16 @@ nouveau_connector_detect(struct drm_connector *connector, bool force) > nv_connector->edid = NULL; > } > > - /* Outputs are only polled while runtime active, so acquiring a > - * runtime PM ref here is unnecessary (and would deadlock upon > - * runtime suspend because it waits for polling to finish). > + /* Outputs are only polled while runtime active, so resuming the > + * device here is unnecessary (and would deadlock upon runtime suspend > + * because it waits for polling to finish). We do however, want to > + * prevent the autosuspend timer from elapsing during this operation > + * if possible. > */ > - if (!drm_kms_helper_is_poll_worker()) { > - ret = pm_runtime_get_sync(connector->dev->dev); > + if (drm_kms_helper_is_poll_worker()) { > + pm_runtime_get_noresume(dev->dev); > + } else { > + ret = pm_runtime_get_sync(dev->dev); > if (ret < 0 && ret != -EACCES) > return conn_status; > } > @@ -655,10 +659,8 @@ nouveau_connector_detect(struct drm_connector *connector, bool force) > > out: > > - if (!drm_kms_helper_is_poll_worker()) { > - pm_runtime_mark_last_busy(connector->dev->dev); > - pm_runtime_put_autosuspend(connector->dev->dev); > - } > + pm_runtime_mark_last_busy(dev->dev); > + pm_runtime_put_autosuspend(dev->dev); > > return conn_status; > } > -- > 2.17.1 > > _______________________________________________ > Nouveau mailing list > Nouveau@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/nouveau
diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c index 2a45b4c2ceb0..010d6db14cba 100644 --- a/drivers/gpu/drm/nouveau/nouveau_connector.c +++ b/drivers/gpu/drm/nouveau/nouveau_connector.c @@ -572,12 +572,16 @@ nouveau_connector_detect(struct drm_connector *connector, bool force) nv_connector->edid = NULL; } - /* Outputs are only polled while runtime active, so acquiring a - * runtime PM ref here is unnecessary (and would deadlock upon - * runtime suspend because it waits for polling to finish). + /* Outputs are only polled while runtime active, so resuming the + * device here is unnecessary (and would deadlock upon runtime suspend + * because it waits for polling to finish). We do however, want to + * prevent the autosuspend timer from elapsing during this operation + * if possible. */ - if (!drm_kms_helper_is_poll_worker()) { - ret = pm_runtime_get_sync(connector->dev->dev); + if (drm_kms_helper_is_poll_worker()) { + pm_runtime_get_noresume(dev->dev); + } else { + ret = pm_runtime_get_sync(dev->dev); if (ret < 0 && ret != -EACCES) return conn_status; } @@ -655,10 +659,8 @@ nouveau_connector_detect(struct drm_connector *connector, bool force) out: - if (!drm_kms_helper_is_poll_worker()) { - pm_runtime_mark_last_busy(connector->dev->dev); - pm_runtime_put_autosuspend(connector->dev->dev); - } + pm_runtime_mark_last_busy(dev->dev); + pm_runtime_put_autosuspend(dev->dev); return conn_status; }
It's true we can't resume the device from poll workers in nouveau_connector_detect(). We can however, prevent the autosuspend timer from elapsing immediately if it hasn't already without risking any sort of deadlock with the runtime suspend/resume operations. So do that instead of entirely avoiding grabbing a power reference. Signed-off-by: Lyude Paul <lyude@redhat.com> Cc: stable@vger.kernel.org Cc: Lukas Wunner <lukas@wunner.de> Cc: Karol Herbst <karolherbst@gmail.com> --- drivers/gpu/drm/nouveau/nouveau_connector.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-)