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From: Brett A C Sheffield <bacs@librecast.net>
To: stable@vger.kernel.org
Cc: regressions@lists.linux.dev, linux-kernel@vger.kernel.org,
	linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
	Javier Martinez Canillas <javierm@redhat.com>,
	Simona Vetter <simona@ffwll.ch>, Helge Deller <deller@gmx.de>,
	Thomas Zimmermann <tzimmermann@suse.de>,
	Lee Jones <lee@kernel.org>,
	Murad Masimov <m.masimov@mt-integration.ru>,
	Yongzhen Zhang <zhangyongzhen@kylinos.cn>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Sasha Levin <sashal@kernel.org>,
	Brett A C Sheffield <bacs@librecast.net>
Subject: [PATCH 1/1] Revert "fbdev: Disable sysfb device registration when removing conflicting FBs"
Date: Wed, 10 Sep 2025 09:38:03 +0000	[thread overview]
Message-ID: <20250910095124.6213-5-bacs@librecast.net> (raw)
In-Reply-To: <20250910095124.6213-3-bacs@librecast.net>

This reverts commit 13d28e0c79cbf69fc6f145767af66905586c1249.

Commit ee7a69aa38d8 ("fbdev: Disable sysfb device registration when
removing conflicting FBs") was backported to 5.15.y LTS. This causes a
regression where all virtual consoles stop responding during boot at:

"Populating /dev with existing devices through uevents ..."

Reverting the commit fixes the regression.

Signed-off-by: Brett A C Sheffield <bacs@librecast.net>
---
 drivers/video/fbdev/core/fbmem.c | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index d938c31e8f90..3b52ddfe0350 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -19,7 +19,6 @@
 #include <linux/kernel.h>
 #include <linux/major.h>
 #include <linux/slab.h>
-#include <linux/sysfb.h>
 #include <linux/mm.h>
 #include <linux/mman.h>
 #include <linux/vt.h>
@@ -1795,17 +1794,6 @@ int remove_conflicting_framebuffers(struct apertures_struct *a,
 		do_free = true;
 	}
 
-	/*
-	 * If a driver asked to unregister a platform device registered by
-	 * sysfb, then can be assumed that this is a driver for a display
-	 * that is set up by the system firmware and has a generic driver.
-	 *
-	 * Drivers for devices that don't have a generic driver will never
-	 * ask for this, so let's assume that a real driver for the display
-	 * was already probed and prevent sysfb to register devices later.
-	 */
-	sysfb_disable();
-
 	mutex_lock(&registration_lock);
 	do_remove_conflicting_framebuffers(a, name, primary);
 	mutex_unlock(&registration_lock);
-- 
2.49.1


  reply	other threads:[~2025-09-10  9:52 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-09-10  9:38 [REGRESSION 5.15.y][BISECTED][PATCH 0/1] console hangs at uevents Brett A C Sheffield
2025-09-10  9:38 ` Brett A C Sheffield [this message]
2025-09-10 10:46   ` [PATCH 1/1] Revert "fbdev: Disable sysfb device registration when removing conflicting FBs" Javier Martinez Canillas
2025-09-10 10:52     ` Brett A C Sheffield
2025-09-10 11:01       ` Sasha Levin
2025-09-10 11:09       ` Javier Martinez Canillas

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