Messages in this thread | | | Date | Thu, 20 Oct 2022 09:43:04 +0200 | From | Greg Kroah-Hartman <> | Subject | Re: [PATCH printk v2 02/38] printk: Convert console_drivers list to hlist |
| |
On Wed, Oct 19, 2022 at 11:52:53PM +0206, John Ogness wrote: > On 2022-10-19, Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote: > >> diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c > >> index e4f1e7478b52..867becc40021 100644 > >> --- a/kernel/printk/printk.c > >> +++ b/kernel/printk/printk.c > >> @@ -3229,32 +3244,30 @@ int unregister_console(struct console *console) > >> if (res > 0) > >> return 0; > >> > >> - res = -ENODEV; > >> console_lock(); > >> - if (console_drivers == console) { > >> - console_drivers=console->next; > >> - res = 0; > >> - } else { > >> - for_each_console(con) { > >> - if (con->next == console) { > >> - con->next = console->next; > >> - res = 0; > >> - break; > >> - } > >> - } > >> + > >> + /* Disable it unconditionally */ > >> + console->flags &= ~CON_ENABLED; > >> + > >> + if (hlist_unhashed(&console->node)) { > > > > How can this ever be hit? The console lock is held, so it shouldn't > > have gone away already. Or am I missing something else here? > > Mainline also has this check. I expect it is for the case that some code > tries to call unregister_console() for a console that is not > registered. > > Since register_console() does not return if it succeeded, I suppose some > code somewhere my try to unregister without knowing that it never > registered in the first place.
Ick, ok, that's fine for now.
What a mess, thanks for working to unwind it!
greg k-h
| |