Messages in this thread | | | Date | Mon, 14 Feb 2022 14:35:41 +0900 | From | Sergey Senozhatsky <> | Subject | Re: [PATCH v3] printk: use atomic updates for klogd work |
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On (22/02/11 12:29), John Ogness wrote: > The per-cpu @printk_pending variable can be updated from > sleepable contexts, such as: > > get_random_bytes() > warn_unseeded_randomness() > printk_deferred() > defer_console_output() > > and can be updated from interrupt contexts, such as: > > handle_irq_event_percpu() > __irq_wake_thread() > wake_up_process() > try_to_wake_up() > select_task_rq() > select_fallback_rq() > printk_deferred() > defer_console_output() > > and can be updated from NMI contexts, such as: > > vprintk() > if (in_nmi()) defer_console_output() > > Therefore the atomic variant of the updating functions must be used. > > Replace __this_cpu_xchg() with this_cpu_xchg(). > Replace __this_cpu_or() with this_cpu_or(). > > Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > Signed-off-by: John Ogness <john.ogness@linutronix.de>
FWIW Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
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