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* FAILED: patch "[PATCH] fbcon: Retry rotated font allocation after failure" failed to apply to 6.1-stable tree
@ 2026-11-07 10:52 Sasha Levin
  2026-11-11  0:16 ` [PATCH 6.1.y] fbcon: Retry rotated font allocation after failure Sasha Levin
  0 siblings, 1 reply; 2+ messages in thread
From: Sasha Levin @ 2026-11-07 10:52 UTC (permalink / raw)
  To: yaoyiqi3, tzimmermann, deller; +Cc: stable

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 7935db1a4a0f83a63590a222500e5016e2f6c85e
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '20261107055256-failed-6.1-7935db1a4a0f@kernel.org' --subject-prefix 'PATCH 6.1.y' 'HEAD^..'

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From 7935db1a4a0f83a63590a222500e5016e2f6c85e Mon Sep 17 00:00:00 2001
From: Yao Yiqi <yaoyiqi3@huawei.com>
Date: Mon, 19 Oct 2026 17:43:31 +0800
Subject: [PATCH] fbcon: Retry rotated font allocation after failure

fbcon_rotate_font() records the font, its geometry and the rotation in
par->rotated before calling font_data_rotate(). If the allocation
fails, the error path clears par->rotated.buf, but the recorded key
already looks up to date, so the next call takes the early-out and
never retries. The rotated putcs/cursor ops keep returning early on
the NULL buffer, and the console stays blank even after memory is
available again.

Also test par->rotated.buf in the early-out, so a failed allocation
is retried on the next call: at the next fbcon_switch(),
fbcon_modechanged() or font change.

Fixes: e4ef723d8975 ("fbcon: Avoid OOB font access if console rotation fails")
Cc: stable@vger.kernel.org
Signed-off-by: Yao Yiqi <yaoyiqi3@huawei.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
---
 drivers/video/fbdev/core/fbcon_rotate.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/core/fbcon_rotate.c b/drivers/video/fbdev/core/fbcon_rotate.c
index 660a3fa81baed..7afd63dcee7be 100644
--- a/drivers/video/fbdev/core/fbcon_rotate.c
+++ b/drivers/video/fbdev/core/fbcon_rotate.c
@@ -25,7 +25,8 @@ int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
 	    par->rotate == par->rotated.buf_rotate &&
 	    vc->vc_font.width == par->rotated.buf_width &&
 	    vc->vc_font.height == par->rotated.buf_height &&
-	    vc->vc_font.charcount == par->rotated.buf_charcount)
+	    vc->vc_font.charcount == par->rotated.buf_charcount &&
+	    par->rotated.buf)
 		return 0;
 
 	par->rotated.fontdata = par->p->fontdata;
-- 
2.53.0





^ permalink raw reply related	[flat|nested] 2+ messages in thread

* [PATCH 6.1.y] fbcon: Retry rotated font allocation after failure
  2026-11-07 10:52 FAILED: patch "[PATCH] fbcon: Retry rotated font allocation after failure" failed to apply to 6.1-stable tree Sasha Levin
@ 2026-11-11  0:16 ` Sasha Levin
  0 siblings, 0 replies; 2+ messages in thread
From: Sasha Levin @ 2026-11-11  0:16 UTC (permalink / raw)
  To: stable; +Cc: Yao Yiqi, Thomas Zimmermann, Helge Deller, Sasha Levin

From: Yao Yiqi <yaoyiqi3@huawei.com>

[ Upstream commit 7935db1a4a0f83a63590a222500e5016e2f6c85e ]

fbcon_rotate_font() records the font, its geometry and the rotation in
par->rotated before calling font_data_rotate(). If the allocation
fails, the error path clears par->rotated.buf, but the recorded key
already looks up to date, so the next call takes the early-out and
never retries. The rotated putcs/cursor ops keep returning early on
the NULL buffer, and the console stays blank even after memory is
available again.

Also test par->rotated.buf in the early-out, so a failed allocation
is retried on the next call: at the next fbcon_switch(),
fbcon_modechanged() or font change.

Fixes: e4ef723d8975 ("fbcon: Avoid OOB font access if console rotation fails")
Cc: stable@vger.kernel.org
Signed-off-by: Yao Yiqi <yaoyiqi3@huawei.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
[ sashal: adapted the buffer check from par->rotated.buf to par->fontbuffer ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/video/fbdev/core/fbcon_rotate.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/core/fbcon_rotate.c b/drivers/video/fbdev/core/fbcon_rotate.c
index a3f507825eed8..3105682075c87 100644
--- a/drivers/video/fbdev/core/fbcon_rotate.c
+++ b/drivers/video/fbdev/core/fbcon_rotate.c
@@ -27,7 +27,8 @@ static int fbcon_rotate_font(struct fb_info *info, struct vc_data *vc)
 	u8 *dst;
 
 	if (vc->vc_font.data == par->fontdata &&
-	    par->p->con_rotate == par->cur_rotate)
+	    par->p->con_rotate == par->cur_rotate &&
+	    par->fontbuffer)
 		goto finished;
 
 	src = par->fontdata = vc->vc_font.data;
-- 
2.53.0


^ permalink raw reply related	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2026-11-11  0:17 UTC | newest]

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2026-11-07 10:52 FAILED: patch "[PATCH] fbcon: Retry rotated font allocation after failure" failed to apply to 6.1-stable tree Sasha Levin
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