| From a16c4bd6090cfa4f2c04f9583756a9734620e1c4 Mon Sep 17 00:00:00 2001 |
| From: Matt Redfearn <matt.redfearn@imgtec.com> |
| Date: Mon, 19 Dec 2016 14:20:56 +0000 |
| Subject: [PATCH] MIPS: Introduce irq_stack |
| |
| commit fe8bd18ffea5327344d4ec2bf11f47951212abd0 upstream. |
| |
| Allocate a per-cpu irq stack for use within interrupt handlers. |
| |
| Also add a utility function on_irq_stack to determine if a given stack |
| pointer is within the irq stack for that cpu. |
| |
| Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> |
| Acked-by: Jason A. Donenfeld <jason@zx2c4.com> |
| Cc: Thomas Gleixner <tglx@linutronix.de> |
| Cc: Paolo Bonzini <pbonzini@redhat.com> |
| Cc: Chris Metcalf <cmetcalf@mellanox.com> |
| Cc: Petr Mladek <pmladek@suse.com> |
| Cc: James Hogan <james.hogan@imgtec.com> |
| Cc: Paul Burton <paul.burton@imgtec.com> |
| Cc: Aaron Tomlin <atomlin@redhat.com> |
| Cc: Andrew Morton <akpm@linux-foundation.org> |
| Cc: linux-kernel@vger.kernel.org |
| Cc: linux-mips@linux-mips.org |
| Patchwork: https://patchwork.linux-mips.org/patch/14740/ |
| Signed-off-by: Ralf Baechle <ralf@linux-mips.org> |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| |
| diff --git a/arch/mips/include/asm/irq.h b/arch/mips/include/asm/irq.h |
| index 15e0fecbc300..ebb9efb02502 100644 |
| --- a/arch/mips/include/asm/irq.h |
| +++ b/arch/mips/include/asm/irq.h |
| @@ -17,6 +17,18 @@ |
| |
| #include <irq.h> |
| |
| +#define IRQ_STACK_SIZE THREAD_SIZE |
| + |
| +extern void *irq_stack[NR_CPUS]; |
| + |
| +static inline bool on_irq_stack(int cpu, unsigned long sp) |
| +{ |
| + unsigned long low = (unsigned long)irq_stack[cpu]; |
| + unsigned long high = low + IRQ_STACK_SIZE; |
| + |
| + return (low <= sp && sp <= high); |
| +} |
| + |
| #ifdef CONFIG_I8259 |
| static inline int irq_canonicalize(int irq) |
| { |
| diff --git a/arch/mips/kernel/asm-offsets.c b/arch/mips/kernel/asm-offsets.c |
| index fae2f9447792..4be2763f835d 100644 |
| --- a/arch/mips/kernel/asm-offsets.c |
| +++ b/arch/mips/kernel/asm-offsets.c |
| @@ -102,6 +102,7 @@ void output_thread_info_defines(void) |
| OFFSET(TI_REGS, thread_info, regs); |
| DEFINE(_THREAD_SIZE, THREAD_SIZE); |
| DEFINE(_THREAD_MASK, THREAD_MASK); |
| + DEFINE(_IRQ_STACK_SIZE, IRQ_STACK_SIZE); |
| BLANK(); |
| } |
| |
| diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c |
| index f25f7eab7307..2b0a371b42af 100644 |
| --- a/arch/mips/kernel/irq.c |
| +++ b/arch/mips/kernel/irq.c |
| @@ -25,6 +25,8 @@ |
| #include <linux/atomic.h> |
| #include <asm/uaccess.h> |
| |
| +void *irq_stack[NR_CPUS]; |
| + |
| /* |
| * 'what should we do if we get a hw irq event on an illegal vector'. |
| * each architecture has to answer this themselves. |
| @@ -58,6 +60,15 @@ void __init init_IRQ(void) |
| clear_c0_status(ST0_IM); |
| |
| arch_init_irq(); |
| + |
| + for_each_possible_cpu(i) { |
| + int irq_pages = IRQ_STACK_SIZE / PAGE_SIZE; |
| + void *s = (void *)__get_free_pages(GFP_KERNEL, irq_pages); |
| + |
| + irq_stack[i] = s; |
| + pr_debug("CPU%d IRQ stack at 0x%p - 0x%p\n", i, |
| + irq_stack[i], irq_stack[i] + IRQ_STACK_SIZE); |
| + } |
| } |
| |
| #ifdef CONFIG_DEBUG_STACKOVERFLOW |
| -- |
| 2.12.0 |
| |