Re: [PATCH][UHCI-DEBUG] Don't kmalloc with BKL held

From: Sven-Thorsten Dietrich
Date: Sat Oct 03 2009 - 08:36:34 EST


On Fri, 2009-10-02 at 09:20 +0000, Frederik Deweerdt wrote:
> Hi Sven-Thorsten,
>
> On Fri, Oct 02, 2009 at 11:12:24AM +0200, Sven-Thorsten Dietrich wrote:
> > Subject: Don't kmalloc with BKL held.
> > From: Sven-Thorsten Dietrich <sdietrich@xxxxxxx>
> >
> > I'm eyeballing this file for complete removal of lock_kernel but
> > at first glance, we definitely don't need BKL to kmalloc().
> You need to move the unlock_kernel() above the out: label too.
>

How about this ?

Subject: Don't kmalloc with BKL held.
From: Sven-Thorsten Dietrich sdietrich@xxxxxxx Sat Oct 3 01:27:27 2009 -0700
Date: Sat Oct 3 01:27:27 2009 -0700:
Git: 4f62eb81e827eb857129101e49757d84ac9ee7eb

We don't need BKL to kmalloc

diff --git a/drivers/usb/host/uhci-debug.c b/drivers/usb/host/uhci-debug.c
index e52b954..3fd5602 100644
--- a/drivers/usb/host/uhci-debug.c
+++ b/drivers/usb/host/uhci-debug.c
@@ -494,32 +494,30 @@ static int uhci_debug_open(struct inode *inode, struct file *file)
{
struct uhci_hcd *uhci = inode->i_private;
struct uhci_debug *up;
- int ret = -ENOMEM;
unsigned long flags;

- lock_kernel();
up = kmalloc(sizeof(*up), GFP_KERNEL);
if (!up)
- goto out;
+ return -ENOMEM;

up->data = kmalloc(MAX_OUTPUT, GFP_KERNEL);
if (!up->data) {
kfree(up);
- goto out;
+ return -ENOMEM;
}

up->size = 0;
+
+ lock_kernel();
spin_lock_irqsave(&uhci->lock, flags);
if (uhci->is_initialized)
up->size = uhci_sprint_schedule(uhci, up->data, MAX_OUTPUT);
spin_unlock_irqrestore(&uhci->lock, flags);

file->private_data = up;
-
- ret = 0;
-out:
unlock_kernel();
- return ret;
+
+ return 0;
}

static loff_t uhci_debug_lseek(struct file *file, loff_t off, int whence)


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