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FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; DNSWL_BLOCKED(0.00)[2a07:de40:b281:106:10:150:64:167:received,2a07:de40:b281:104:10:150:64:97:from]; RCVD_VIA_SMTP_AUTH(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.com:url,imap1.dmz-prg2.suse.org:rdns,imap1.dmz-prg2.suse.org:helo,suse.de:mid,suse.de:dkim] X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Rspamd-Queue-Id: B65806BF76 X-Spam-Level: Hi Am 11.05.26 um 19:22 schrieb Icenowy Zheng: > 在 2026-05-12二的 02:01 +0900，Myeonghun Pak写道： >> lsdc_pci_probe() initializes KMS polling before setting up vblank >> support, >> requesting the IRQ and registering the DRM device. If any of those >> later >> steps fails, probe returns without finalizing polling. The remove >> path has >> the same lifetime gap when tearing down a successfully registered >> device. >> >> Route those probe failures through a poll cleanup label. Also >> finalize >> polling from remove before unregistering the DRM device. > Interesting, but it looks like a `drmm_kms_helper_poll_init` function > exists (while rarely used). > > Maybe it's better to switch to this? Or maybe there's some reason not > to use this? Agreed. DRM drivers are advised to use managed cleanup for their data structures. So rather switch to drmm_kms_helper_poll_init(). That also resolves the problem that loongson never calls poll_fini on regular removals. Best regards Thomas > > Thanks, > Icenowy > >> This issue was identified during our ongoing static-analysis research >> while >> reviewing kernel code. >> >> Fixes: f39db26c5428 ("drm: Add kms driver for loongson display >> controller") >> Cc: stable@vger.kernel.org >> Co-developed-by: Ijae Kim >> Signed-off-by: Ijae Kim >> Signed-off-by: Myeonghun Pak >> --- >>  drivers/gpu/drm/loongson/lsdc_drv.c | 11 ++++++++--- >>  1 file changed, 8 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/gpu/drm/loongson/lsdc_drv.c >> b/drivers/gpu/drm/loongson/lsdc_drv.c >> index abf5bf68ee..3db1f8690a 100644 >> --- a/drivers/gpu/drm/loongson/lsdc_drv.c >> +++ b/drivers/gpu/drm/loongson/lsdc_drv.c >> @@ -297,7 +297,7 @@ static int lsdc_pci_probe(struct pci_dev *pdev, >> const struct pci_device_id *ent) >>   if (loongson_vblank) { >>   ret = drm_vblank_init(ddev, descp->num_of_crtc); >>   if (ret) >> - return ret; >> + goto err_poll_fini; >> >>   ret = devm_request_irq(&pdev->dev, pdev->irq, >>          descp->funcs->irq_handler, >> @@ -305,7 +305,7 @@ static int lsdc_pci_probe(struct pci_dev *pdev, >> const struct pci_device_id *ent) >>          dev_name(&pdev->dev), ddev); >>   if (ret) { >>   drm_err(ddev, "Failed to register interrupt: >> %d\n", ret); >> - return ret; >> + goto err_poll_fini; >>   } >> >>   drm_info(ddev, "registered irq: %u\n", pdev->irq); >> @@ -313,17 +313,22 @@ static int lsdc_pci_probe(struct pci_dev *pdev, >> const struct pci_device_id *ent) >> >>   ret = drm_dev_register(ddev, 0); >>   if (ret) >> - return ret; >> + goto err_poll_fini; >> >>   drm_client_setup(ddev, NULL); >> >>   return 0; >> + >> +err_poll_fini: >> + drm_kms_helper_poll_fini(ddev); >> + return ret; >>  } >> >>  static void lsdc_pci_remove(struct pci_dev *pdev) >>  { >>   struct drm_device *ddev = pci_get_drvdata(pdev); >> >> + drm_kms_helper_poll_fini(ddev); >>   drm_dev_unregister(ddev); >>   drm_atomic_helper_shutdown(ddev); >>  } -- -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)