diff -urNp --exclude CVS --exclude BitKeeper --exclude {arch} --exclude .arch-ids x-ref/arch/i386/kernel/irq.c x/arch/i386/kernel/irq.c
--- x-ref/arch/i386/kernel/irq.c 2003-10-01 17:59:39.000000000 +0200
+++ x/arch/i386/kernel/irq.c 2003-10-01 18:03:02.000000000 +0200
@@ -560,6 +560,10 @@ void enable_irq(unsigned int irq)
spin_unlock_irqrestore(&desc->lock, flags);
}
+#ifdef CONFIG_DEBUG_STACKOVERFLOW
+int sysctl_stackwarn = 1024;
+#endif
+
/*
* do_IRQ handles all normal device IRQ's (the special
* SMP cross-CPU interrupts have their own specific
@@ -587,13 +591,17 @@ asmlinkage unsigned int do_IRQ(struct pt
/* Debugging check for stack overflow: is there less than 1KB free? */
__asm__ __volatile__("andl %%esp,%0" : "=r" (esp) : "0" (8191));
- if (unlikely(esp < (sizeof(struct task_struct) + 1024))) {
- extern void show_stack(unsigned long *);
-
- printk("do_IRQ: stack overflow: %ld\n",
- esp - sizeof(struct task_struct));
- __asm__ __volatile__("movl %%esp,%0" : "=r" (esp));
- show_stack((void *)esp);
+ if (unlikely(esp < (sizeof(struct task_struct) + sysctl_stackwarn))) {
+ static unsigned long next_jiffies; /* ratelimiting */
+ static long least_esp = THREAD_SIZE;
+
+ if (time_after(jiffies, next_jiffies) || (esp < least_esp)) {
+ least_esp = esp;
+ next_jiffies = jiffies + 5*HZ;
+ printk("WARNING: do_IRQ: near stack overflow: %ld\n",
+ esp - sizeof(struct task_struct));
+ dump_stack();
+ }
}
#endif
diff -urNp --exclude CVS --exclude BitKeeper --exclude {arch} --exclude .arch-ids x-ref/arch/i386/kernel/traps.c x/arch/i386/kernel/traps.c
--- x-ref/arch/i386/kernel/traps.c 2003-10-01 17:59:39.000000000 +0200
+++ x/arch/i386/kernel/traps.c 2003-10-01 18:03:02.000000000 +0200
@@ -202,21 +202,27 @@ void show_trace(unsigned long * stack)
{
int i;
unsigned long addr;
+ unsigned long *prev = NULL;
if (!stack)
stack = (unsigned long*)&stack;
- printk("Call Trace: ");
+ printk("Call Trace: ");
i = 1;
while (((long) stack & (THREAD_SIZE-1)) != 0) {
addr = *stack++;
if (kernel_text_address(addr)) {
- if (i && ((i % 6) == 0))
+ if (prev)
+ printk(" (%02d)", (stack-prev)*sizeof(*stack));
+ prev = stack;
+ if ((i % 4) == 0)
printk("\n ");
printk(" [<%08lx>]", addr);
i++;
}
}
+ if (prev)
+ printk(" (%02d)", (stack-prev)*sizeof(*stack));
printk("\n");
}
@@ -259,6 +265,7 @@ void show_stack(unsigned long * esp)
void dump_stack(void)
{
show_stack(0);
+ printk("Code: <0>\n"); /* tell ksymoops trace ends here */
}
void show_registers(struct pt_regs *regs)
diff -urNp --exclude CVS --exclude BitKeeper --exclude {arch} --exclude .arch-ids x-ref/arch/x86_64/kernel/irq.c x/arch/x86_64/kernel/irq.c
--- x-ref/arch/x86_64/kernel/irq.c 2003-10-01 17:59:43.000000000 +0200
+++ x/arch/x86_64/kernel/irq.c 2003-10-01 18:03:02.000000000 +0200
@@ -47,6 +47,8 @@
#include <asm/proto.h>
#ifdef CONFIG_DEBUG_STACKOVERFLOW
+int sysctl_stackwarn = 128;
+
/*
* Probalistic stack overflow check:
*
@@ -66,7 +68,7 @@ static inline void stack_overflow_check(
}
if (regs->rsp >= curbase && regs->rsp <= curbase + THREAD_SIZE &&
- regs->rsp < curbase + sizeof(struct task_struct) + 128 &&
+ regs->rsp < curbase + sizeof(struct task_struct) + sysctl_stackwarn &&
warned + 60*HZ >= jiffies) {
printk("do_IRQ: %s near stack overflow (cur:%Lx,rsp:%lx)\n",
current->comm, curbase, regs->rsp);
diff -urNp --exclude CVS --exclude BitKeeper --exclude {arch} --exclude .arch-ids x-ref/include/linux/sysctl.h x/include/linux/sysctl.h
--- x-ref/include/linux/sysctl.h 2003-10-01 17:59:43.000000000 +0200
+++ x/include/linux/sysctl.h 2003-10-01 18:03:19.000000000 +0200
@@ -135,6 +135,8 @@ enum
KERN_MAXTIMESLICE=62, /* int: nice -20 max timeslice */
KERN_MINTIMESLICE=63, /* int: nice +19 min timeslice */
KERN_HZ=64, /* unsigned long: interal kernel HZ */
+ KERN_STACKWARN=65, /* int: do_IRQ warn when stackspace is less */
+ KERN_STACKDEFER=66, /* int: do_softirq defer if stackspace less */
};
diff -urNp --exclude CVS --exclude BitKeeper --exclude {arch} --exclude .arch-ids x-ref/kernel/softirq.c x/kernel/softirq.c
--- x-ref/kernel/softirq.c 2003-10-01 17:59:40.000000000 +0200
+++ x/kernel/softirq.c 2003-10-01 18:03:48.000000000 +0200
@@ -18,6 +18,15 @@
#include <linux/tqueue.h>
#include <linux/profiler.h>
+#if !defined(CONFIG_PARISC) && \
+ !defined(CONFIG_ARCH_S390) && !defined(CONFIG_X86_64)
+
+#define DEBUG_DUMP_DEEP_STACK 0
+
+int sysctl_stackdefer = 80 * BITS_PER_LONG;
+
+#endif
+
/*
- No shared variables, all the data are CPU local.
- If a softirq needs serialization, let it serialize itself
@@ -97,6 +106,33 @@ asmlinkage void do_softirq(void)
if (pending) {
struct softirq_action *h;
+#if !defined(CONFIG_PARISC) && \
+ !defined(CONFIG_ARCH_S390) && !defined(CONFIG_X86_64)
+ {
+ unsigned long esp = (unsigned long) &esp;
+ unsigned long tsk = (unsigned long) current;
+
+ if (unlikely(esp < tsk + sizeof(struct task_struct) +
+ sysctl_stackdefer) && esp >= tsk &&
+ tsk != (unsigned long) ksoftirqd_task(cpu)) {
+#if DEBUG_DUMP_DEEP_STACK
+ static unsigned long next_jiffies;
+ if (time_after(jiffies, next_jiffies)) {
+ next_jiffies = jiffies + 5*HZ;
+ printk("WARNING: do_softirq: "
+ "deferring from stack at %ld\n",
+ esp-tsk-sizeof(struct task_struct));
+ dump_stack();
+ }
+#endif /* DEBUG_DUMP_DEEP_STACK */
+
+ wakeup_softirqd(cpu);
+ local_irq_restore(flags);
+ return;
+ }
+ }
+#endif /* !CONFIG_PARISC !CONFIG_ARCH_S390 !CONFIG_X86_64 */
+
mask = ~pending;
local_bh_disable();
restart:
diff -urNp --exclude CVS --exclude BitKeeper --exclude {arch} --exclude .arch-ids x-ref/kernel/sysctl.c x/kernel/sysctl.c
--- x-ref/kernel/sysctl.c 2003-10-01 17:59:43.000000000 +0200
+++ x/kernel/sysctl.c 2003-10-01 18:04:40.000000000 +0200
@@ -100,6 +100,14 @@ extern int sysctl_ieee_emulation_warning
extern int sysctl_userprocess_debug;
#endif
+#ifdef CONFIG_DEBUG_STACKOVERFLOW
+extern int sysctl_stackwarn;
+#endif
+#if !defined(CONFIG_PARISC) && \
+ !defined(CONFIG_ARCH_S390) && !defined(CONFIG_X86_64)
+extern int sysctl_stackdefer;
+#endif
+
#ifdef CONFIG_PPC32
extern unsigned long zero_paged_on, powersave_nap;
int proc_dol2crvec(ctl_table *table, int write, struct file *filp,
@@ -298,6 +306,15 @@ static ctl_table kern_table[] = {
&min_timeslice,sizeof(int),0644,NULL,&proc_dointvec},
{KERN_HZ, "HZ",
&__HZ, sizeof(unsigned long),0444,NULL,&proc_doulongvec_minmax},
+#ifdef CONFIG_DEBUG_STACKOVERFLOW
+ {KERN_STACKWARN, "stackwarn", &sysctl_stackwarn, sizeof(int),
+ 0644, NULL, &proc_dointvec},
+#endif
+#if !defined(CONFIG_PARISC) && \
+ !defined(CONFIG_ARCH_S390) && !defined(CONFIG_X86_64)
+ {KERN_STACKDEFER, "stackdefer", &sysctl_stackdefer, sizeof(int),
+ 0644, NULL, &proc_dointvec},
+#endif
{0}
};