path: root/arch/x86/include
diff options
authorThomas Gleixner <tglx@linutronix.de>2020-06-10 08:37:01 +0200
committerThomas Gleixner <tglx@linutronix.de>2020-06-11 15:15:29 +0200
commitf0178fc01fe46bab6a95415f5647d1a74efcad1b (patch)
treebf263d8cacf2ada33dea4cbc16ee5fd46b0109d4 /arch/x86/include
parent2823e83a3dc0f54d23db67ca07d74b9c8bb1fdda (diff)
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 <cai@lca.pw> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/include')
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/x86/include/asm/irq.h b/arch/x86/include/asm/irq.h
index f73dd3f8b043..528c8a71fe7f 100644
--- a/arch/x86/include/asm/irq.h
+++ b/arch/x86/include/asm/irq.h
@@ -11,6 +11,13 @@
#include <asm/apicdef.h>
#include <asm/irq_vectors.h>
+ * The irq entry code is in the noinstr section and the start/end of
+ * __irqentry_text is emitted via labels. Make the build fail if
+ * something moves a C function into the __irq_entry section.
+ */
+#define __irq_entry __invalid_section
static inline int irq_canonicalize(int irq)
return ((irq == 2) ? 9 : irq);