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Date: Fri, 4 Feb 2022 21:06:38 +0100 From: Sam Ravnborg <sam@...nborg.org> To: Daniel Vetter <daniel.vetter@...ll.ch> Cc: DRI Development <dri-devel@...ts.freedesktop.org>, linux-fbdev@...r.kernel.org, Du Cheng <ducheng2@...il.com>, Tetsuo Handa <penguin-kernel@...ove.sakura.ne.jp>, Intel Graphics Development <intel-gfx@...ts.freedesktop.org>, LKML <linux-kernel@...r.kernel.org>, Claudio Suarez <cssk@...-c.es>, Greg Kroah-Hartman <gregkh@...uxfoundation.org>, Daniel Vetter <daniel.vetter@...el.com> Subject: Re: [PATCH 18/21] fbcon: untangle fbcon_exit Hi Daniel, On Mon, Jan 31, 2022 at 10:05:49PM +0100, Daniel Vetter wrote: > There's a bunch of confusions going on here: > - The deferred fbcon setup notifier should only be cleaned up from > fb_console_exit(), to be symmetric with fb_console_init() > - We also need to make sure we don't race with the work, which means > temporarily dropping the console lock (or we can deadlock) > - That also means no point in clearing deferred_takeover, we are > unloading everything anyway. > - Finally rename fbcon_exit to fbcon_release_all and move it, since > that's what's it doing when being called from consw->con_deinit > through fbcon_deinit. > > Signed-off-by: Daniel Vetter <daniel.vetter@...el.com> > Cc: Daniel Vetter <daniel@...ll.ch> > Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org> > Cc: Claudio Suarez <cssk@...-c.es> > Cc: Du Cheng <ducheng2@...il.com> > Cc: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp> > --- > drivers/video/fbdev/core/fbcon.c | 63 ++++++++++++++++---------------- > 1 file changed, 32 insertions(+), 31 deletions(-) > > diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c > index 5c14e24d14a1..22581952b4fd 100644 > --- a/drivers/video/fbdev/core/fbcon.c > +++ b/drivers/video/fbdev/core/fbcon.c > @@ -185,7 +185,6 @@ static void fbcon_set_disp(struct fb_info *info, struct fb_var_screeninfo *var, > int unit); > static void fbcon_modechanged(struct fb_info *info); > static void fbcon_set_all_vcs(struct fb_info *info); > -static void fbcon_exit(void); > > static struct device *fbcon_device; > > @@ -1149,6 +1148,27 @@ static void fbcon_free_font(struct fbcon_display *p, bool freefont) > > static void set_vc_hi_font(struct vc_data *vc, bool set); > > +static void fbcon_release_all(void) > +{ > + struct fb_info *info; > + int i, j, mapped; > + > + for_each_registered_fb(i) { > + mapped = 0; > + info = registered_fb[i]; > + > + for (j = first_fb_vc; j <= last_fb_vc; j++) { > + if (con2fb_map[j] == i) { > + mapped = 1; > + con2fb_map[j] = -1; > + } > + } > + > + if (mapped) > + fbcon_release(info); > + } > +} > + > static void fbcon_deinit(struct vc_data *vc) > { > struct fbcon_display *p = &fb_display[vc->vc_num]; > @@ -1188,7 +1208,7 @@ static void fbcon_deinit(struct vc_data *vc) > set_vc_hi_font(vc, false); > > if (!con_is_bound(&fb_con)) > - fbcon_exit(); > + fbcon_release_all(); > > if (vc->vc_num == logo_shown) > logo_shown = FBCON_LOGO_CANSHOW; > @@ -3316,34 +3336,6 @@ static void fbcon_start(void) > #endif > } > > -static void fbcon_exit(void) > -{ > - struct fb_info *info; > - int i, j, mapped; > - > -#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER > - if (deferred_takeover) { > - dummycon_unregister_output_notifier(&fbcon_output_nb); > - deferred_takeover = false; > - } > -#endif > - > - for_each_registered_fb(i) { > - mapped = 0; > - info = registered_fb[i]; > - > - for (j = first_fb_vc; j <= last_fb_vc; j++) { > - if (con2fb_map[j] == i) { > - mapped = 1; > - con2fb_map[j] = -1; > - } > - } > - > - if (mapped) > - fbcon_release(info); > - } > -} > - > void __init fb_console_init(void) > { > int i; > @@ -3383,10 +3375,19 @@ static void __exit fbcon_deinit_device(void) > > void __exit fb_console_exit(void) > { > +#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER > + console_lock(); > + if (deferred_takeover) > + dummycon_unregister_output_notifier(&fbcon_output_nb); > + console_unlock(); > + > + cancel_work_sync(&fbcon_deferred_takeover_work); > +#endif > + > console_lock(); > fbcon_deinit_device(); > device_destroy(fb_class, MKDEV(0, 0)); > - fbcon_exit(); > + We loose the call to fbcon_release_all() here. We have part of the old fbcon_exit() above, but miss the release parts. Maybe I missed something obvious? The rest looks fine. Sam > do_unregister_con_driver(&fb_con); > console_unlock(); > } > -- > 2.33.0
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