From: Linus Torvalds <torvalds@linux-foundation.org> stable inclusion from stable-v6.6.59 commit 7a26cb660775067a4d7da6ca48e024a8543bf848 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IB6YDK Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/id=7... -------------------------------- commit cec6937dd1aae1b38d147bd190cb895d06cf96d0 upstream. The TWA_NMI_CURRENT handling very much depends on IRQ_WORK, but that isn't universally enabled everywhere. Maybe the IRQ_WORK infrastructure should just be unconditional - x86 ends up indirectly enabling it through unconditionally enabling PERF_EVENTS, for example. But it also gets enabled by having SMP support, or even if you just have PRINTK enabled. But in the meantime TWA_NMI_CURRENT causes tons of build failures on various odd minimal configs. Which did show up in linux-next, but despite that nobody bothered to fix it or even inform me until -rc1 was out. Fixes: 466e4d801cd4 ("task_work: Add TWA_NMI_CURRENT as an additional notify mode") Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Reported-by: kernelci.org bot <bot@kernelci.org> Reported-by: Guenter Roeck <linux@roeck-us.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Liu Kai <liukai284@huawei.com> --- kernel/task_work.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/task_work.c b/kernel/task_work.c index 8aa43204cb7dd..c969f1f26be58 100644 --- a/kernel/task_work.c +++ b/kernel/task_work.c @@ -6,12 +6,14 @@ static struct callback_head work_exited; /* all we need is ->next == NULL */ +#ifdef CONFIG_IRQ_WORK static void task_work_set_notify_irq(struct irq_work *entry) { test_and_set_tsk_thread_flag(current, TIF_NOTIFY_RESUME); } static DEFINE_PER_CPU(struct irq_work, irq_work_NMI_resume) = IRQ_WORK_INIT_HARD(task_work_set_notify_irq); +#endif /** * task_work_add - ask the @task to execute @work->func() @@ -59,6 +61,8 @@ int task_work_add(struct task_struct *task, struct callback_head *work, if (notify == TWA_NMI_CURRENT) { if (WARN_ON_ONCE(task != current)) return -EINVAL; + if (!IS_ENABLED(CONFIG_IRQ_WORK)) + return -EINVAL; } else { /* * Record the work call stack in order to print it in KASAN @@ -92,9 +96,11 @@ int task_work_add(struct task_struct *task, struct callback_head *work, case TWA_SIGNAL_NO_IPI: __set_notify_signal(task); break; +#ifdef CONFIG_IRQ_WORK case TWA_NMI_CURRENT: irq_work_queue(this_cpu_ptr(&irq_work_NMI_resume)); break; +#endif default: WARN_ON_ONCE(1); break; -- 2.34.1