From b6548122a8c89c570baccfa1d15002a6711b1f72 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner <tglx@linutronix.de> Date: Fri, 24 Sep 2021 17:05:48 +0200 Subject: [PATCH 131/166] generic/softirq: Disable softirq stacks on PREEMPT_RT PREEMPT_RT preempts softirqs and the current implementation avoids do_softirq_own_stack() and only uses __do_softirq(). Disable the unused softirqs stacks on PREEMPT_RT to safe some memory and ensure that do_softirq_own_stack() is not used which is not expected. [bigeasy: commit description.] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- include/asm-generic/softirq_stack.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: linux-5.15.32-rt39/include/asm-generic/softirq_stack.h =================================================================== @ linux-5.15.32-rt39/include/asm-generic/softirq_stack.h:5 @ #ifndef __ASM_GENERIC_SOFTIRQ_STACK_H #define __ASM_GENERIC_SOFTIRQ_STACK_H -#ifdef CONFIG_HAVE_SOFTIRQ_ON_OWN_STACK +#if defined(CONFIG_HAVE_SOFTIRQ_ON_OWN_STACK) && !defined(CONFIG_PREEMPT_RT) void do_softirq_own_stack(void); #else static inline void do_softirq_own_stack(void)