Messages in this thread | | | Date | Tue, 15 Nov 2022 17:41:24 +0100 | From | Petr Mladek <> | Subject | Re: replay log: Re: [PATCH printk v4 38/39] printk: relieve console_lock of list synchronization duties |
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On Tue 2022-11-15 16:34:10, Petr Mladek wrote: > On Mon 2022-11-14 17:35:31, John Ogness wrote: > > The console_list_lock provides synchronization for console list and > > console->flags updates. All call sites that were using the console_lock > > for this synchronization have either switched to use the > > console_list_lock or the SRCU list iterator. > > > > Remove console_lock usage for console list updates and console->flags > > updates. > > > > Signed-off-by: John Ogness <john.ogness@linutronix.de> > > > --- a/kernel/printk/printk.c > > +++ b/kernel/printk/printk.c > > @@ -3334,6 +3330,11 @@ void register_console(struct console *newcon) > > * boot console that is the furthest behind. > > */ > > if (bootcon_registered && !keep_bootcon) { > > + /* > > + * Hold the console_lock to guarantee safe access to > > + * console->seq. > > + */ > > + console_lock(); > > for_each_console(con) { > > if ((con->flags & CON_BOOT) && > > (con->flags & CON_ENABLED) && > > @@ -3341,6 +3342,7 @@ void register_console(struct console *newcon) > > newcon->seq = con->seq; > > } > > } > > + console_unlock(); > > Thinking more about it. This console_unlock() will actually cause > flushing the boot consoles. A solution would be to call > console_flush_all() here. > > And we could/should solve this in a separate patch. This code was not locked > before. It is a corner case. It could be solved later. > > > } > > } > >
The rest of the patch looks fine. I checked hopefully console_list walks and console flags manipulations and everything looks good.
So, without the above two hunks:
Reviewed-by: Petr Mladek <pmladek@suse.com>
Best Regards, Petr
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