On 8/17/25 4:43 AM, Fedor Pchelkin wrote: > amdgpu_dm_connector_ddc_get_modes() reinitializes a connector's probed > modes list without cleaning it up. First time it is called during the > driver's initialization phase, then via drm_mode_getconnector() ioctl. > The leaks observed with Kmemleak are as following: > > unreferenced object 0xffff88812f91b200 (size 128): > comm "(udev-worker)", pid 388, jiffies 4294695475 > hex dump (first 32 bytes): > ac dd 07 00 80 02 70 0b 90 0b e0 0b 00 00 e0 01 ......p......... > 0b 07 10 07 5c 07 00 00 0a 00 00 00 00 00 00 00 ....\........... > backtrace (crc 89db554f): > __kmalloc_cache_noprof+0x3a3/0x490 > drm_mode_duplicate+0x8e/0x2b0 > amdgpu_dm_create_common_mode+0x40/0x150 [amdgpu] > amdgpu_dm_connector_add_common_modes+0x336/0x488 [amdgpu] > amdgpu_dm_connector_get_modes+0x428/0x8a0 [amdgpu] > amdgpu_dm_initialize_drm_device+0x1389/0x17b4 [amdgpu] > amdgpu_dm_init.cold+0x157b/0x1a1e [amdgpu] > dm_hw_init+0x3f/0x110 [amdgpu] > amdgpu_device_ip_init+0xcf4/0x1180 [amdgpu] > amdgpu_device_init.cold+0xb84/0x1863 [amdgpu] > amdgpu_driver_load_kms+0x15/0x90 [amdgpu] > amdgpu_pci_probe+0x391/0xce0 [amdgpu] > local_pci_probe+0xd9/0x190 > pci_call_probe+0x183/0x540 > pci_device_probe+0x171/0x2c0 > really_probe+0x1e1/0x890 > > Found by Linux Verification Center (linuxtesting.org). > > Fixes: acc96ae0d127 ("drm/amd/display: set panel orientation before > drm_dev_register") > Cc: sta...@vger.kernel.org > Signed-off-by: Fedor Pchelkin <pchel...@ispras.ru> > --- > > I can't reproduce the issue before the commit in Fixes which placed that > extra amdgpu_dm_connector_get_modes() call. Though the reinitializing part > > /* empty probed_modes */ > INIT_LIST_HEAD(&connector->probed_modes); > > was added years before and it looks OK since drm_connector_list_update() > should shake the list in between drm_mode_getconnector() ioctl calls. > > > For what the patch does there exists a drm_mode_remove() helper but it's > static at drivers/gpu/drm/drm_connector.c and requires to be exported > first. This probably looks like a subject for an independent for-next > patch, if needed.
So you're saying this change will take two iterations of patches to ping pong the code? Why not just send this as a two patch series? 1) Export the symbol drm_mode_remove() 2) This patch, but use the symbol. > > drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c > b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c > index cd0e2976e268..4b84f944f066 100644 > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c > @@ -8227,9 +8227,14 @@ static void amdgpu_dm_connector_ddc_get_modes(struct > drm_connector *connector, > { > struct amdgpu_dm_connector *amdgpu_dm_connector = > to_amdgpu_dm_connector(connector); > + struct drm_display_mode *mode, *t; > > if (drm_edid) { > /* empty probed_modes */ > + list_for_each_entry_safe(mode, t, &connector->probed_modes, > head) { > + list_del(&mode->head); > + drm_mode_destroy(connector->dev, mode); > + } > INIT_LIST_HEAD(&connector->probed_modes); > amdgpu_dm_connector->num_modes = > drm_edid_connector_add_modes(connector);