diff options
Diffstat (limited to 'target/linux/generic/patches-4.9/040-01-MIPS-Introduce-irq_stack.patch')
| -rw-r--r-- | target/linux/generic/patches-4.9/040-01-MIPS-Introduce-irq_stack.patch | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/target/linux/generic/patches-4.9/040-01-MIPS-Introduce-irq_stack.patch b/target/linux/generic/patches-4.9/040-01-MIPS-Introduce-irq_stack.patch new file mode 100644 index 0000000..1cdbcda --- /dev/null +++ b/target/linux/generic/patches-4.9/040-01-MIPS-Introduce-irq_stack.patch @@ -0,0 +1,70 @@ +From: Matt Redfearn <matt.redfearn@imgtec.com> +Date: Mon, 19 Dec 2016 14:20:56 +0000 +Subject: [PATCH] MIPS: Introduce irq_stack + +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> +--- + +--- 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 <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 |