Commit f75593ce authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
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USB: EHCI: fix DMA deallocation bug 



This patch (as1440) fixes a bug in ehci-hcd.  ehci->periodic_size is
used to compute the size in a dma_alloc_coherent() call, but then it
gets changed later on.  As a result, the corresponding call to
dma_free_coherent() passes a different size from the original
allocation.  Fix the problem by adjusting ehci->periodic_size before
carrying out any of the memory allocations.

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Tested-by: default avatarLarry Finger <Larry.Finger@lwfinger.net>
CC: David Brownell <david-b@pacbell.net>
CC: <stable@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 06f1b971

drivers/usb/host/ehci-hcd.c

+12 −7
Original line number Diff line number Diff line
@@ -572,6 +572,8 @@ static int ehci_init(struct usb_hcd *hcd) 
	ehci->iaa_watchdog.function = ehci_iaa_watchdog;

	ehci->iaa_watchdog.data = (unsigned long) ehci;



	hcc_params = ehci_readl(ehci, &ehci->caps->hcc_params);



	/*

	 * hw default: 1K periodic list heads, one per frame.

	 * periodic_size can shrink by USBCMD update if hcc_params allows.
@@ -579,11 +581,20 @@ static int ehci_init(struct usb_hcd *hcd) 
	ehci->periodic_size = DEFAULT_I_TDPS;

	INIT_LIST_HEAD(&ehci->cached_itd_list);

	INIT_LIST_HEAD(&ehci->cached_sitd_list);



	if (HCC_PGM_FRAMELISTLEN(hcc_params)) {

		/* periodic schedule size can be smaller than default */

		switch (EHCI_TUNE_FLS) {

		case 0: ehci->periodic_size = 1024; break;

		case 1: ehci->periodic_size = 512; break;

		case 2: ehci->periodic_size = 256; break;

		default:	BUG();

		}

	}

	if ((retval = ehci_mem_init(ehci, GFP_KERNEL)) < 0)

		return retval;



	/* controllers may cache some of the periodic schedule ... */

	hcc_params = ehci_readl(ehci, &ehci->caps->hcc_params);

	if (HCC_ISOC_CACHE(hcc_params))		// full frame cache

		ehci->i_thresh = 2 + 8;

	else					// N microframes cached
@@ -637,12 +648,6 @@ static int ehci_init(struct usb_hcd *hcd) 
		/* periodic schedule size can be smaller than default */

		temp &= ~(3 << 2);

		temp |= (EHCI_TUNE_FLS << 2);

		switch (EHCI_TUNE_FLS) {

		case 0: ehci->periodic_size = 1024; break;

		case 1: ehci->periodic_size = 512; break;

		case 2: ehci->periodic_size = 256; break;

		default:	BUG();

		}

	}

	if (HCC_LPM(hcc_params)) {

		/* support link power management EHCI 1.1 addendum */

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