Messages in this thread Patch in this message | | | From | Keith Packard <> | Subject | [PATCH] [drivers/video/fb] Eliminate recursive mutex in compat fb ioctl path | Date | Sun, 2 Nov 2008 23:06:50 -0800 |
| |
fb_compat_ioctl grabbed the fb mutex and then called fb_ioctl, which also grabs the same mutex. I traced through all existing fb_compat_ioctl functions in the various fb drivers and found that they also transform their arguments and call the native fb_ioctl function. So, it is correct to just remove the mutex_lock/mutex_unlock pair in the top-level compat path.
Signed-off-by: Keith Packard <keithp@keithp.com> --- drivers/video/fbmem.c | 2 -- 1 files changed, 0 insertions(+), 2 deletions(-)
diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c index cd5f20d..548cf26 100644 --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -1253,7 +1253,6 @@ fb_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) struct fb_ops *fb = info->fbops; long ret = -ENOIOCTLCMD; - mutex_lock(&info->lock); switch(cmd) { case FBIOGET_VSCREENINFO: case FBIOPUT_VSCREENINFO: @@ -1279,7 +1278,6 @@ fb_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) ret = fb->fb_compat_ioctl(info, cmd, arg); break; } - mutex_unlock(&info->lock); return ret; } #endif -- 1.5.6.5
| |