lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

ACPI / sysfs: Add support to allow leading "\" missing in trace_method_name.

Browse Source 
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>
This commit is contained in:
Lv Zheng 2015-08-05 16:23:57 +08:00 committed by Rafael J. Wysocki
parent 7901a052a9
commit a0186bcf7c
1 changed files with 13 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
drivers/acpi/sysfs.c
View File

@ -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,