On Fri, Aug 26, 2022 at 04:19:27PM +0200, Andrzej Hajda wrote: > i915->hotplug.dig_port_work can be queued from intel_hpd_irq_handler > called by IRQ handler or by intel_hpd_trigger_irq called from dp_mst. > Since dp_mst is suspended after irq handler uninstall, a cleaner approach > is to cancel hpd work after intel_dp_mst_suspend, otherwise we risk > use-after-free. > > It should fix following WARNINGS: > [283.405824] cpu_latency_qos_update_request called for unknown object > [283.405866] WARNING: CPU: 2 PID: 240 at kernel/power/qos.c:296 cpu_latency_qos_update_request+0x2d/0x100 > [283.405912] CPU: 2 PID: 240 Comm: kworker/u64:9 Not tainted 5.18.0-rc6-Patchwork_103738v3-g1672d1c43e43+ #1 > [283.405915] Hardware name: Intel Corporation Raptor Lake Client Platform/RPL-S ADP-S DDR5 UDIMM CRB, BIOS RPLSFWI1.R00.2397.A01.2109300731 09/30/2021 > [283.405916] Workqueue: i915-dp i915_digport_work_func [i915] > [283.406020] RIP: 0010:cpu_latency_qos_update_request+0x2d/0x100 > ... > [283.406040] Call Trace: > [283.406041] <TASK> > [283.406044] intel_dp_aux_xfer+0x60e/0x8e0 [i915] > [283.406131] ? finish_swait+0x80/0x80 > [283.406139] intel_dp_aux_transfer+0xc5/0x2b0 [i915] > [283.406218] drm_dp_dpcd_access+0x79/0x130 [drm_display_helper] > [283.406227] drm_dp_dpcd_read+0xe2/0xf0 [drm_display_helper] > [283.406233] intel_dp_hpd_pulse+0x134/0x570 [i915] > [283.406308] ? __down_killable+0x70/0x140 > [283.406313] i915_digport_work_func+0xba/0x150 [i915] > > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/4586 > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/5558 > Signed-off-by: Andrzej Hajda <andrzej.hajda@xxxxxxxxx> > Reviewed-by: Arun R Murthy <arun.r.murthy@xxxxxxxxx> Reviewed-by: Imre Deak <imre.deak@xxxxxxxxx> > --- > drivers/gpu/drm/i915/display/intel_display.c | 14 +++++++------- > 1 file changed, 7 insertions(+), 7 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c > index a0f84cbe974fc3..524c4580ae6bc9 100644 > --- a/drivers/gpu/drm/i915/display/intel_display.c > +++ b/drivers/gpu/drm/i915/display/intel_display.c > @@ -9000,6 +9000,13 @@ void intel_modeset_driver_remove(struct drm_i915_private *i915) > > flush_work(&i915->atomic_helper.free_work); > drm_WARN_ON(&i915->drm, !llist_empty(&i915->atomic_helper.free_list)); > + > + /* > + * MST topology needs to be suspended so we don't have any calls to > + * fbdev after it's finalized. MST will be destroyed later as part of > + * drm_mode_config_cleanup() > + */ > + intel_dp_mst_suspend(i915); > } > > /* part #2: call after irq uninstall */ > @@ -9014,13 +9021,6 @@ void intel_modeset_driver_remove_noirq(struct drm_i915_private *i915) > */ > intel_hpd_poll_fini(i915); > > - /* > - * MST topology needs to be suspended so we don't have any calls to > - * fbdev after it's finalized. MST will be destroyed later as part of > - * drm_mode_config_cleanup() > - */ > - intel_dp_mst_suspend(i915); > - > /* poll work can call into fbdev, hence clean that up afterwards */ > intel_fbdev_fini(i915); > > -- > 2.25.1 >
