lkml.org 
[lkml]   [2021]   [Sep]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5.10 076/103] vt_kdsetmode: extend console locking
Date
From: Linus Torvalds <torvalds@linux-foundation.org>

commit 2287a51ba822384834dafc1c798453375d1107c7 upstream.

As per the long-suffering comment.

Reported-by: Minh Yuan <yuanmingbuaa@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/tty/vt/vt_ioctl.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

--- a/drivers/tty/vt/vt_ioctl.c
+++ b/drivers/tty/vt/vt_ioctl.c
@@ -246,6 +246,8 @@ int vt_waitactive(int n)
*
* XXX It should at least call into the driver, fbdev's definitely need to
* restore their engine state. --BenH
+ *
+ * Called with the console lock held.
*/
static int vt_kdsetmode(struct vc_data *vc, unsigned long mode)
{
@@ -262,7 +264,6 @@ static int vt_kdsetmode(struct vc_data *
return -EINVAL;
}

- /* FIXME: this needs the console lock extending */
if (vc->vc_mode == mode)
return 0;

@@ -271,12 +272,10 @@ static int vt_kdsetmode(struct vc_data *
return 0;

/* explicitly blank/unblank the screen if switching modes */
- console_lock();
if (mode == KD_TEXT)
do_unblank_screen(1);
else
do_blank_screen(1);
- console_unlock();

return 0;
}
@@ -378,7 +377,10 @@ static int vt_k_ioctl(struct tty_struct
if (!perm)
return -EPERM;

- return vt_kdsetmode(vc, arg);
+ console_lock();
+ ret = vt_kdsetmode(vc, arg);
+ console_unlock();
+ return ret;

case KDGETMODE:
return put_user(vc->vc_mode, (int __user *)arg);

\
 
 \ /
  Last update: 2021-09-01 14:45    [W:1.045 / U:0.784 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site