> -----Original Message----- > From: Joerg Platte [mailto:li...@naasa.net] > Sent: Sunday, August 23, 2015 11:26 PM > To: Deucher, Alexander; linux-kernel@vger.kernel.org > Subject: drm/radeon: take the mode_config mutex when dealing with hpds > (v2) crashes > > Dear Alex, > > on my old P4 based non-SMP router your patch (commit > 32d12fc20e3c726ca858d0e5055fb596fce2f8bc in linux stable) crashes on > Linux 4.1.4 and above. I was only able to take a picture of the whole > trace https://ferdi.naasa.net/url/jplatte/IMG_3116.JPG > > Reverting the patch resolves the issue. > > This is my old graphics hardware: > 01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. > [AMD/ATI] RV100 [Radeon 7000 / Radeon VE] > > Just for the reference, here is the full patch: > commit 32d12fc20e3c726ca858d0e5055fb596fce2f8bc > Author: Alex Deucher <alexander.deuc...@amd.com> > Date: Fri May 15 11:48:52 2015 -0400 > > drm/radeon: take the mode_config mutex when dealing with hpds (v2) > > commit 39fa10f7e21574a70cecf1fed0f9b36535aa68a0 upstream. > > Since we are messing with state in the worker. > > v2: drop the changes in the mst worker > > Signed-off-by: Alex Deucher <alexander.deuc...@amd.com> > Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> > > diff --git a/drivers/gpu/drm/radeon/radeon_irq_kms.c > b/drivers/gpu/drm/radeon/radeon_irq_kms.c > index 7162c93..f682e53 100644 > --- a/drivers/gpu/drm/radeon/radeon_irq_kms.c > +++ b/drivers/gpu/drm/radeon/radeon_irq_kms.c > @@ -79,10 +79,12 @@ static void radeon_hotplug_work_func(struct > work_struct *work) > struct drm_mode_config *mode_config = &dev->mode_config; > struct drm_connector *connector; > > + mutex_lock(&mode_config->mutex); > if (mode_config->num_connector) { > list_for_each_entry(connector, > &mode_config->connector_list, head) > radeon_connector_hotplug(connector); > } > + mutex_unlock(&mode_config->mutex); > /* Just fire off a uevent and let userspace tell us what to do */ > drm_helper_hpd_irq_event(dev); > } > > Is it possible that the mutex is not defined on non-SMP systems? Can you > help to resolve this regression?
Fixed in: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7f98ca454ad373fc1b76be804fa7138ff68c1d27 Alex > > Best regards, > Joerg N�����r��y����b�X��ǧv�^�){.n�+����{����zX����ܨ}���Ơz�&j:+v�������zZ+��+zf���h���~����i���z� �w���?�����&�)ߢf��^jǫy�m��@A�a��� 0��h���i
