| | From | Paul Gortmaker <> | | Subject | [34-longterm 016/247] USB: EHCI: fix DMA deallocation bug | | Date | Thu, 23 Jun 2011 13:17:39 -0400 |
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From: Alan Stern <stern@rowland.harvard.edu>
------------------- This is a commit scheduled for the next v2.6.34 longterm release. If you see a problem with using this for longterm, please comment. ------------------- commit f75593ceaa08e6d27aec1a5de31cded19e850dd1 upstream.
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: Alan Stern <stern@rowland.harvard.edu> Tested-by: Larry Finger <Larry.Finger@lwfinger.net> CC: David Brownell <david-b@pacbell.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> --- drivers/usb/host/ehci-hcd.c | 19 ++++++++++++------- 1 files changed, 12 insertions(+), 7 deletions(-) diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index 8b6b270..5a32023 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -545,6 +545,8 @@ 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. @@ -552,11 +554,20 @@ 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 @@ -605,12 +616,6 @@ 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(); - } } ehci->command = temp; -- 1.7.4.4
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