summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/sysfs.c
diff options
context:
space:
mode:
authorLv Zheng <lv.zheng@intel.com>2015-08-05 10:23:57 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2015-08-07 02:42:22 +0200
commita0186bcf7c21907c78ab2b4bc50f3fb2b5047806 (patch)
tree2826d7cbdddc8d61d4cf5660d5d9aee69b6dfe30 /drivers/acpi/sysfs.c
parentACPI / sysfs: Update method tracing facility. (diff)
downloadlinux-a0186bcf7c21907c78ab2b4bc50f3fb2b5047806.tar.xz
linux-a0186bcf7c21907c78ab2b4bc50f3fb2b5047806.zip
ACPI / sysfs: Add support to allow leading "\" missing in trace_method_name.
Since _SB.PCI0 can be used as relative path from root and can be easily converted into internal trace_method_name format, we allow users to specify trace_method_name using relative paths from root. Note this is useful for grub2 for which users failed to pass "\" from the grub configuration file. Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/sysfs.c')
-rw-r--r--drivers/acpi/sysfs.c28
1 files changed, 13 insertions, 15 deletions
diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c
index 8979e4a8d066..40a42655227c 100644
--- a/drivers/acpi/sysfs.c
+++ b/drivers/acpi/sysfs.c
@@ -164,14 +164,18 @@ static const struct kernel_param_ops param_ops_debug_level = {
module_param_cb(debug_layer, &param_ops_debug_layer, &acpi_dbg_layer, 0644);
module_param_cb(debug_level, &param_ops_debug_level, &acpi_dbg_level, 0644);
-static char* trace_method_name;
-static bool trace_method_kmalloced;
+static char trace_method_name[1024];
int param_set_trace_method_name(const char *val, const struct kernel_param *kp)
{
u32 saved_flags = 0;
+ bool is_abs_path = true;
- if (strlen(val) > 1024) {
+ if (*val != '\\')
+ is_abs_path = false;
+
+ if ((is_abs_path && strlen(val) > 1023) ||
+ (!is_abs_path && strlen(val) > 1022)) {
pr_err("%s: string parameter too long\n", kp->name);
return -ENOSPC;
}
@@ -187,19 +191,13 @@ int param_set_trace_method_name(const char *val, const struct kernel_param *kp)
acpi_gbl_trace_dbg_layer,
0);
- if (trace_method_kmalloced)
- kfree(trace_method_name);
- trace_method_name = NULL;
- trace_method_kmalloced = false;
-
/* This is a hack. We can't kmalloc in early boot. */
- if (slab_is_available()) {
- trace_method_name = kstrdup(val, GFP_KERNEL);
- if (!trace_method_name)
- return -ENOMEM;
- trace_method_kmalloced = true;
- } else
- trace_method_name = (char *)val;
+ if (is_abs_path)
+ strcpy(trace_method_name, val);
+ else {
+ trace_method_name[0] = '\\';
+ strcpy(trace_method_name+1, val);
+ }
/* Restore the original tracer state */
(void)acpi_debug_trace(trace_method_name,