ACPI: thinkpad-acpi: allow for syscall restart in sysfs handlers
Map an mutex_lock_interruptible() error return into ERESTARTSYS, as the
only possible error from mutex_lock_interruptible is EINTR, and that will
only happen if signal_pending() causes the mutex lock attempt to abort.
This still allows signals to be delivered ASAP, which is much nicer than
just doing mutex_lock, and still shadows userspace from EINTR when
SA_RESTART is active.
Problem reported by Peter Jordan.
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Peter Jordan <usernetwork@gmx.info>
Cc: Richard Neill <rn214@hermes.cam.ac.uk>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c
index 251110d..306daa5 100644
--- a/drivers/misc/thinkpad_acpi.c
+++ b/drivers/misc/thinkpad_acpi.c
@@ -1342,9 +1342,8 @@
return len;
}
- res = mutex_lock_interruptible(&hotkey_mutex);
- if (res < 0)
- return res;
+ if (mutex_lock_interruptible(&hotkey_mutex))
+ return -ERESTARTSYS;
res = hotkey_get(&status, &mask);
mutex_unlock(&hotkey_mutex);
if (res)
@@ -1373,9 +1372,8 @@
if (!tp_features.hotkey)
return -ENODEV;
- res = mutex_lock_interruptible(&hotkey_mutex);
- if (res < 0)
- return res;
+ if (mutex_lock_interruptible(&hotkey_mutex))
+ return -ERESTARTSYS;
res = hotkey_get(&status, &mask);
if (res)
@@ -3768,9 +3766,8 @@
/* scale down from 0-255 to 0-7 */
newlevel = (s >> 5) & 0x07;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
rc = fan_get_status(&status);
if (!rc && (status &
@@ -4020,9 +4017,8 @@
int rc;
u8 s;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
rc = fan_get_status(&s);
if (!rc)
fan_update_desired_level(s);
@@ -4156,9 +4152,8 @@
if (!fan_control_allowed)
return -EPERM;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
if (level == TPACPI_FAN_LAST_LEVEL)
level = fan_control_desired_level;
@@ -4179,9 +4174,8 @@
if (!fan_control_allowed)
return -EPERM;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
switch (fan_control_access_mode) {
case TPACPI_FAN_WR_ACPI_FANS:
@@ -4235,9 +4229,8 @@
if (!fan_control_allowed)
return -EPERM;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
rc = 0;
switch (fan_control_access_mode) {
@@ -4274,9 +4267,8 @@
if (!fan_control_allowed)
return -EPERM;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
rc = 0;
switch (fan_control_access_mode) {