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| author | Don Mullis <dwm@meer.net> | 2006-12-08 02:39:52 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.osdl.org> | 2006-12-08 08:29:03 -0800 |
| commit | a124c28ef85d9b780c418b2c5d8f01cd6a06ff3e (patch) | |
| tree | 8312c4991138c7696eab4a85a245d0e677a79f04 /lib/fault-inject.c | |
| parent | 08b3df2d16cbebf7d72c09dcbc071696c14d07e3 (diff) | |
| download | lwn-a124c28ef85d9b780c418b2c5d8f01cd6a06ff3e.tar.gz lwn-a124c28ef85d9b780c418b2c5d8f01cd6a06ff3e.zip | |
[PATCH] fault-injection: Clamp debugfs stacktrace-depth to MAX_STACK_TRACE_DEPTH
Clamp /debug/fail*/stacktrace-depth to MAX_STACK_TRACE_DEPTH. Ensures that a
read of /debug/fail*/stacktrace-depth always returns a truthful answer.
Signed-off-by: Don Mullis <dwm@meer.net>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'lib/fault-inject.c')
| -rw-r--r-- | lib/fault-inject.c | 27 |
1 files changed, 23 insertions, 4 deletions
diff --git a/lib/fault-inject.c b/lib/fault-inject.c index 244782940349..5da665ac2d89 100644 --- a/lib/fault-inject.c +++ b/lib/fault-inject.c @@ -53,6 +53,8 @@ static bool fail_task(struct fault_attr *attr, struct task_struct *task) return !in_interrupt() && task->make_it_fail; } +#define MAX_STACK_TRACE_DEPTH 32 + #ifdef CONFIG_STACK_UNWIND static asmlinkage int fail_stacktrace_callback(struct unwind_frame_info *info, @@ -98,8 +100,7 @@ static bool fail_stacktrace(struct fault_attr *attr) trace.nr_entries = 0; trace.entries = entries; - trace.max_entries = (depth < MAX_STACK_TRACE_DEPTH) ? - depth : MAX_STACK_TRACE_DEPTH; + trace.max_entries = depth; trace.skip = 1; trace.all_contexts = 0; @@ -179,6 +180,13 @@ static void debugfs_ul_set(void *data, u64 val) *(unsigned long *)data = val; } +static void debugfs_ul_set_MAX_STACK_TRACE_DEPTH(void *data, u64 val) +{ + *(unsigned long *)data = + val < MAX_STACK_TRACE_DEPTH ? + val : MAX_STACK_TRACE_DEPTH; +} + static u64 debugfs_ul_get(void *data) { return *(unsigned long *)data; @@ -192,6 +200,17 @@ static struct dentry *debugfs_create_ul(const char *name, mode_t mode, return debugfs_create_file(name, mode, parent, value, &fops_ul); } +DEFINE_SIMPLE_ATTRIBUTE(fops_ul_MAX_STACK_TRACE_DEPTH, debugfs_ul_get, + debugfs_ul_set_MAX_STACK_TRACE_DEPTH, "%llu\n"); + +static struct dentry *debugfs_create_ul_MAX_STACK_TRACE_DEPTH( + const char *name, mode_t mode, + struct dentry *parent, unsigned long *value) +{ + return debugfs_create_file(name, mode, parent, value, + &fops_ul_MAX_STACK_TRACE_DEPTH); +} + static void debugfs_atomic_t_set(void *data, u64 val) { atomic_set((atomic_t *)data, val); @@ -284,8 +303,8 @@ int init_fault_attr_dentries(struct fault_attr *attr, const char *name) mode, dir, &attr->task_filter); attr->dentries.stacktrace_depth_file = - debugfs_create_ul("stacktrace-depth", mode, dir, - &attr->stacktrace_depth); + debugfs_create_ul_MAX_STACK_TRACE_DEPTH( + "stacktrace-depth", mode, dir, &attr->stacktrace_depth); attr->dentries.require_start_file = debugfs_create_ul("require-start", mode, dir, &attr->require_start); |