This is a note to let you know that I've just added the patch titled
MIPS: Introduce irq_stack
to the 4.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mips-introduce-irq_stack.patch
and it can be found in the queue-4.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From fe8bd18ffea5327344d4ec2bf11f47951212abd0 Mon Sep 17 00:00:00 2001
From: Matt Redfearn <matt.redfearn@xxxxxxxxxx>
Date: Mon, 19 Dec 2016 14:20:56 +0000
Subject: MIPS: Introduce irq_stack
From: Matt Redfearn <matt.redfearn@xxxxxxxxxx>
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@xxxxxxxxxx>
Acked-by: Jason A. Donenfeld <jason@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Chris Metcalf <cmetcalf@xxxxxxxxxxxx>
Cc: Petr Mladek <pmladek@xxxxxxxx>
Cc: James Hogan <james.hogan@xxxxxxxxxx>
Cc: Paul Burton <paul.burton@xxxxxxxxxx>
Cc: Aaron Tomlin <atomlin@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-mips@xxxxxxxxxxxxxx
Patchwork: https://patchwork.linux-mips.org/patch/14740/
Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/mips/include/asm/irq.h | 12 ++++++++++++
arch/mips/kernel/asm-offsets.c | 1 +
arch/mips/kernel/irq.c | 11 +++++++++++
3 files changed, 24 insertions(+)
--- 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)
{
--- 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();
}
--- a/arch/mips/kernel/irq.c
+++ b/arch/mips/kernel/irq.c
@@ -25,6 +25,8 @@
#include <linux/atomic.h>
#include <linux/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
Patches currently in stable-queue which might be from matt.redfearn@xxxxxxxxxx are
queue-4.10/mips-only-change-28-to-thread_info-if-coming-from-user-mode.patch
queue-4.10/mips-stack-unwinding-while-on-irq-stack.patch
queue-4.10/mips-introduce-irq_stack.patch