Message ID | 20220131210552.482606-8-daniel.vetter@ffwll.ch |
---|---|
State | Superseded |
Headers | show |
Series | some fbcon patches, mostly locking | expand |
On Mon, Jan 31, 2022 at 10:05:38PM +0100, Daniel Vetter wrote: > fb_set_var requires we hold the fb_info lock. Or at least this now > matches what the ioctl does ... > > Note that ps3fb and sh_mobile_lcdcfb are busted in different ways here, > but I will not fix them up. > > Also in practice this isn't a big deal, because really variable fbdev > state is actually protected by console_lock (because fbcon just > doesn't bother with lock_fb_info() at all), and lock_fb_info > protecting anything is really just a neat lie. But that's a much > bigger fish to fry. > > Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> > Cc: Helge Deller <deller@gmx.de> > Cc: Daniel Vetter <daniel@ffwll.ch> > Cc: Qing Wang <wangqing@vivo.com> > Cc: Sam Ravnborg <sam@ravnborg.org> Acked-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/drivers/video/fbdev/core/fbsysfs.c b/drivers/video/fbdev/core/fbsysfs.c index 26892940c213..8c1ee9ecec3d 100644 --- a/drivers/video/fbdev/core/fbsysfs.c +++ b/drivers/video/fbdev/core/fbsysfs.c @@ -91,9 +91,11 @@ static int activate(struct fb_info *fb_info, struct fb_var_screeninfo *var) var->activate |= FB_ACTIVATE_FORCE; console_lock(); + lock_fb_info(fb_info); err = fb_set_var(fb_info, var); if (!err) fbcon_update_vcs(fb_info, var->activate & FB_ACTIVATE_ALL); + unlock_fb_info(fb_info); console_unlock(); if (err) return err;
fb_set_var requires we hold the fb_info lock. Or at least this now matches what the ioctl does ... Note that ps3fb and sh_mobile_lcdcfb are busted in different ways here, but I will not fix them up. Also in practice this isn't a big deal, because really variable fbdev state is actually protected by console_lock (because fbcon just doesn't bother with lock_fb_info() at all), and lock_fb_info protecting anything is really just a neat lie. But that's a much bigger fish to fry. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Helge Deller <deller@gmx.de> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Qing Wang <wangqing@vivo.com> Cc: Sam Ravnborg <sam@ravnborg.org> --- drivers/video/fbdev/core/fbsysfs.c | 2 ++ 1 file changed, 2 insertions(+)