linux-kernel - [PATCH 07/12] drm/qxl: Use devm aperture helpers for sysfb restore on probe failure

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Message-ID: <20251229215906.3688205-8-zack.rusin@broadcom.com>
Date: Mon, 29 Dec 2025 16:58:13 -0500
From: Zack Rusin <zack.rusin@...adcom.com>
To: dri-devel@...ts.freedesktop.org
Cc: Dave Airlie <airlied@...hat.com>,
	Gerd Hoffmann <kraxel@...hat.com>,
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
	Maxime Ripard <mripard@...nel.org>,
	Thomas Zimmermann <tzimmermann@...e.de>,
	David Airlie <airlied@...il.com>,
	Simona Vetter <simona@...ll.ch>,
	virtualization@...ts.linux.dev,
	spice-devel@...ts.freedesktop.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH 07/12] drm/qxl: Use devm aperture helpers for sysfb restore on probe failure

Use devm_aperture_remove_conflicting_pci_devices() instead of the
non-devm variant to automatically restore the system framebuffer
(efifb/simpledrm) if the driver's probe fails after removing the
firmware framebuffer.

Call devm_aperture_remove_conflicting_pci_devices_done() after
successful probe to cancel the automatic restore, as the driver
is now responsible for display output.

This ensures users don't lose display output if the qxl driver
fails to probe after removing the firmware framebuffer.

Signed-off-by: Zack Rusin <zack.rusin@...adcom.com>
Cc: Dave Airlie <airlied@...hat.com>
Cc: Gerd Hoffmann <kraxel@...hat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>
Cc: Maxime Ripard <mripard@...nel.org>
Cc: Thomas Zimmermann <tzimmermann@...e.de>
Cc: David Airlie <airlied@...il.com>
Cc: Simona Vetter <simona@...ll.ch>
Cc: virtualization@...ts.linux.dev
Cc: spice-devel@...ts.freedesktop.org
Cc: dri-devel@...ts.freedesktop.org
Cc: linux-kernel@...r.kernel.org
---
 drivers/gpu/drm/qxl/qxl_drv.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/qxl/qxl_drv.c b/drivers/gpu/drm/qxl/qxl_drv.c
index 2bbb1168a3ff..ca4c817fd611 100644
--- a/drivers/gpu/drm/qxl/qxl_drv.c
+++ b/drivers/gpu/drm/qxl/qxl_drv.c
@@ -93,7 +93,12 @@ qxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (ret)
 		return ret;
 
-	ret = aperture_remove_conflicting_pci_devices(pdev, qxl_driver.name);
+	/*
+	 * Use devm variant to automatically restore sysfb if probe fails.
+	 * This ensures the user doesn't lose display if our probe fails
+	 * after removing the firmware framebuffer (efifb/simpledrm).
+	 */
+	ret = devm_aperture_remove_conflicting_pci_devices(pdev, qxl_driver.name);
 	if (ret)
 		goto disable_pci;
 
@@ -121,6 +126,13 @@ qxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto modeset_cleanup;
 
 	drm_client_setup(&qdev->ddev, NULL);
+
+	/*
+	 * Probe succeeded - cancel the automatic sysfb restore action.
+	 * We're now responsible for display output.
+	 */
+	devm_aperture_remove_conflicting_pci_devices_done(pdev);
+
 	return 0;
 
 modeset_cleanup:
-- 
2.48.1