From f0178fc01fe46bab6a95415f5647d1a74efcad1b Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 10 Jun 2020 08:37:01 +0200 Subject: x86/entry: Unbreak __irqentry_text_start/end magic The entry rework moved interrupt entry code from the irqentry to the noinstr section which made the irqentry section empty. This breaks boundary checks which rely on the __irqentry_text_start/end markers to find out whether a function in a stack trace is interrupt/exception entry code. This affects the function graph tracer and filter_irq_stacks(). As the IDT entry points are all sequentialy emitted this is rather simple to unbreak by injecting __irqentry_text_start/end as global labels. To make this work correctly: - Remove the IRQENTRY_TEXT section from the x86 linker script - Define __irqentry so it breaks the build if it's used - Adjust the entry mirroring in PTI - Remove the redundant kprobes and unwinder bound checks Reported-by: Qian Cai Signed-off-by: Thomas Gleixner --- include/linux/interrupt.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'include/linux/interrupt.h') diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 80f637c3a6f3..5db970b6615a 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -760,8 +760,10 @@ extern int arch_early_irq_init(void); /* * We want to know which function is an entrypoint of a hardirq or a softirq. */ -#define __irq_entry __attribute__((__section__(".irqentry.text"))) -#define __softirq_entry \ - __attribute__((__section__(".softirqentry.text"))) +#ifndef __irq_entry +# define __irq_entry __attribute__((__section__(".irqentry.text"))) +#endif + +#define __softirq_entry __attribute__((__section__(".softirqentry.text"))) #endif -- cgit v1.2.3