mirror of
https://github.com/Ysurac/openmptcprouter.git
synced 2025-02-15 04:42:02 +00:00
41 lines
1.6 KiB
Diff
41 lines
1.6 KiB
Diff
From 1dc23c4753f0d9705f845cc64139b6aa3b476809 Mon Sep 17 00:00:00 2001
|
|
From: Phil Elwell <phil@raspberrypi.com>
|
|
Date: Wed, 29 Mar 2023 09:49:36 +0100
|
|
Subject: [PATCH 704/726] fbdev: Don't cancel deferred work if pagelist empty
|
|
|
|
Since [1], the fbdev deferred IO framework is careful to cancel
|
|
pending updates on close to prevent dirty pages being accessed after
|
|
they may have been reused. However, this is not necessary in the case
|
|
that the pagelist is empty, and drivers that don't make use of the
|
|
pagelist may have wanted updates cancelled for no good reason.
|
|
|
|
Avoid penalising fbdev drivers that don't make use of the pagelist by
|
|
making the cancelling of deferred IO on close conditional on there
|
|
being a non-empty pagelist.
|
|
|
|
See: https://github.com/raspberrypi/linux/issues/5398
|
|
|
|
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
|
|
|
|
[1] 3efc61d95259 ("fbdev: Fix invalid page access after closing deferred I/O devices")
|
|
---
|
|
drivers/video/fbdev/core/fb_defio.c | 3 ++-
|
|
1 file changed, 2 insertions(+), 1 deletion(-)
|
|
|
|
diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c
|
|
index a3cf1f764f29..85da3a21bab2 100644
|
|
--- a/drivers/video/fbdev/core/fb_defio.c
|
|
+++ b/drivers/video/fbdev/core/fb_defio.c
|
|
@@ -321,7 +321,8 @@ static void fb_deferred_io_lastclose(struct fb_info *info)
|
|
struct page *page;
|
|
int i;
|
|
|
|
- cancel_delayed_work_sync(&info->deferred_work);
|
|
+ if (!list_empty(&info->fbdefio->pagereflist))
|
|
+ cancel_delayed_work_sync(&info->deferred_work);
|
|
|
|
/* clear out the mapping that we setup */
|
|
for (i = 0 ; i < info->fix.smem_len; i += PAGE_SIZE) {
|
|
--
|
|
2.33.1
|
|
|