diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 50ae5286f59b..359a3b85c8b3 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1158,7 +1158,6 @@ config CURRENT_POINTER_IN_TPIDRURO config IRQSTACKS def_bool y - depends on MMU select HAVE_IRQ_EXIT_ON_IRQ_STACK select HAVE_SOFTIRQ_ON_OWN_STACK diff --git a/arch/arm/kernel/entry-v7m.S b/arch/arm/kernel/entry-v7m.S index 4e0d318b67c6..de8a60363c85 100644 --- a/arch/arm/kernel/entry-v7m.S +++ b/arch/arm/kernel/entry-v7m.S @@ -40,11 +40,24 @@ __irq_entry: @ Invoke the IRQ handler @ mov r0, sp - stmdb sp!, {lr} + ldr_this_cpu sp, irq_stack_ptr, r1, r2 + + @ + @ If we took the interrupt while running in the kernel, we may already + @ be using the IRQ stack, so revert to the original value in that case. + @ + subs r2, sp, r0 @ SP above bottom of IRQ stack? + rsbscs r2, r2, #THREAD_SIZE @ ... and below the top? + movcs sp, r0 + + push {r0, lr} @ preserve LR and original SP + @ routine called with r0 = struct pt_regs * bl generic_handle_arch_irq - pop {lr} + pop {r0, lr} + mov sp, r0 + @ @ Check for any pending work if returning to user @