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From: Souptick Joarder <jrdr.linux@gmail.com>
To: miguel.ojeda.sandonis@gmail.com
Cc: linux-kernel@vger.kernel.org, willy@infradead.org,
	robin@protonic.nl, Souptick Joarder <jrdr.linux@gmail.com>
Subject: [PATCH 2/2] auxdisplay/ht16k33.c: Convert to use vm_map_pages_zero()
Date: Sun, 26 May 2019 21:41:10 +0530	[thread overview]
Message-ID: <1558887070-4076-1-git-send-email-jrdr.linux@gmail.com> (raw)

While using mmap, the incorrect values of length and vm_pgoff are
ignored and this driver goes ahead with mapping fbdev.buffer
to user vma.

Convert vm_insert_pages() to use vm_map_pages_zero(). We could later
"fix" these drivers to behave according to the normal vm_pgoff
offsetting simply by removing the _zero suffix on the function name
and if that causes regressions, it gives us an easy way to revert.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Acked-by: Robin van der Gracht <robin@protonic.nl>
---
v2: Fixed minor typo. Acked-by tag added.

 drivers/auxdisplay/ht16k33.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/auxdisplay/ht16k33.c b/drivers/auxdisplay/ht16k33.c
index 21393ec..9c0bb77 100644
--- a/drivers/auxdisplay/ht16k33.c
+++ b/drivers/auxdisplay/ht16k33.c
@@ -223,9 +223,9 @@ static int ht16k33_bl_check_fb(struct backlight_device *bl, struct fb_info *fi)
 static int ht16k33_mmap(struct fb_info *info, struct vm_area_struct *vma)
 {
 	struct ht16k33_priv *priv = info->par;
+	struct page *pages = virt_to_page(priv->fbdev.buffer);
 
-	return vm_insert_page(vma, vma->vm_start,
-			      virt_to_page(priv->fbdev.buffer));
+	return vm_map_pages_zero(vma, &pages, 1);
 }
 
 static struct fb_ops ht16k33_fb_ops = {
-- 
1.9.1


             reply	other threads:[~2019-05-26 16:06 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-26 16:11 Souptick Joarder [this message]
  -- strict thread matches above, loose matches on Subject: below --
2019-05-20 15:30 [PATCH 2/2] auxdisplay/ht16k33.c: Convert to use vm_map_pages_zero() Souptick Joarder
2019-05-21  6:55 ` Robin van der Gracht
2019-05-23  8:18   ` Souptick Joarder
2019-05-23 12:58     ` Miguel Ojeda
2019-05-24  4:22       ` Miguel Ojeda
2019-05-24  6:07         ` Souptick Joarder
2019-05-28 19:03           ` Miguel Ojeda
2019-05-23 13:23 ` Miguel Ojeda
2019-05-24  6:10   ` Souptick Joarder

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