linux - Can msleep inside ioctl cause incorrect mutex operation? -

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inside linux driver have ioctl dispatcher, , 1 branch uses msleep() function.

static long p347_fpga_ioctl(struct file *filp, uint cmd, unsigned long arg)  {     long ret_code = 0;     ...      switch (cmd) {         ...         case p347_ioctl_client_start_rot: {             if (arg != 0) {                 ret_code = rot_set_params(trp); //idx                 if (ret_code == 0) {                     ret_code = rot_run(trp->rot_idx);                 } else {                     printk("cannot setup rot channel error=%d\n",ret_code);                 }             }         }     break; }         ...     };     ...     return ret_code; }

int rot_run(unsigned char rot_idx) contains msleep() call

further, userspace program uses of ioctls inside mutex prevent simultaneous calls.

... pthread_mutex_lock(&fmutex); ret = ioctl(dev_desc, p347_ioctl_client_start_rot, &params); pthread_mutex_unlock(&fmutex); ...

that way, can msleep() cause problems?


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