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Subject[PATCH] usblcd: Push down BKL into driver
I'm pretty sure this can be eliminated however I couldn't prove (or find)
what stopped the device vanishing mid IOCTL_GET_HARD_VERSION. Perhaps a
USB wizard could double check that and see if the lock_kernel can go
entirely.

Signed-off-by: Alan Cox <alan@redhat.com>

diff --git a/drivers/usb/misc/usblcd.c b/drivers/usb/misc/usblcd.c
index 7f7021e..2db4228 100644
--- a/drivers/usb/misc/usblcd.c
+++ b/drivers/usb/misc/usblcd.c
@@ -146,7 +146,7 @@ static ssize_t lcd_read(struct file *file, char __user * buffer, size_t count, l
return retval;
}

-static int lcd_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+static long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct usb_lcd *dev;
u16 bcdDevice;
@@ -158,12 +158,14 @@ static int lcd_ioctl(struct inode *inode, struct file *file, unsigned int cmd, u

switch (cmd) {
case IOCTL_GET_HARD_VERSION:
+ lock_kernel();
bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice);
sprintf(buf,"%1d%1d.%1d%1d",
(bcdDevice & 0xF000)>>12,
(bcdDevice & 0xF00)>>8,
(bcdDevice & 0xF0)>>4,
(bcdDevice & 0xF));
+ unlock_kernel();
if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
return -EFAULT;
break;
@@ -272,7 +274,7 @@ static const struct file_operations lcd_fops = {
.read = lcd_read,
.write = lcd_write,
.open = lcd_open,
- .ioctl = lcd_ioctl,
+ .unlocked_ioctl = lcd_ioctl,
.release = lcd_release,
};


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