@@ -32,10 +32,6 @@ static ssize_t rproc_cdev_write(struct file *filp, const char __user *buf, size_
return -EFAULT;
if (!strncmp(cmd, "start", len)) {
- if (rproc->state == RPROC_RUNNING ||
- rproc->state == RPROC_ATTACHED)
- return -EBUSY;
-
ret = rproc_boot(rproc);
} else if (!strncmp(cmd, "stop", len)) {
if (rproc->state != RPROC_RUNNING &&
@@ -194,10 +194,6 @@ static ssize_t state_store(struct device *dev,
int ret = 0;
if (sysfs_streq(buf, "start")) {
- if (rproc->state == RPROC_RUNNING ||
- rproc->state == RPROC_ATTACHED)
- return -EBUSY;
-
ret = rproc_boot(rproc);
if (ret)
dev_err(&rproc->dev, "Boot failed: %d\n", ret);
There is no mutex protection of the state checking before rproc_boot(), which can't guarantee there is no another instance is trying to do same operation. Consider two instances case: Instance1: echo start > /sys/class/remoteproc/remoteproc0/state Instance2: echo start > /sys/class/remoteproc/remoteproc0/state ... Instance2: echo stop > /sys/class/remoteproc/remoteproc0/state ... Instance1: echo stop > /sys/class/remoteproc/remoteproc0/state The one issue is that the instance2 case may success when 'start' happens at same time as instance1, then rproc->power = 2; Or it may fail with -BUSY, then rproc->power = 1; which is uncertain. The another issue is for 'stop' operation, if the rproc->power = 1, when instance2 'stop' the remoteproc the instance1 will be impacted for it still needs the service at that time. The reference counter rproc->power is used to manage state changing and there is mutex protection in each operation function for multi instance case. So remove this state checking in rproc_cdev_write() and state_store() for 'start' operation, just let reference counter rproc->power to manage the behaviors. Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com> --- drivers/remoteproc/remoteproc_cdev.c | 4 ---- drivers/remoteproc/remoteproc_sysfs.c | 4 ---- 2 files changed, 8 deletions(-)