From b3cbcd902db7019410dfe3729a660abcb1f03ffb Mon Sep 17 00:00:00 2001 From: Dirk Behme Date: Fri, 17 Nov 2017 15:28:36 +0100 Subject: [PATCH] usb: ehci: do not invalidate a NULL buffer Its a valid use case to call ehci_submit_async() with a NULL buffer with length 0. E.g. from usb_set_configuration(). As invalidate_dcache_range() isn't able to judge if the address NULL is valid or not (depending on the SoC hardware configuration it might be valid) do the check in ehci_submit_async() as here we know that we don't have to invalidate such a buffer. Signed-off-by: Dirk Behme --- drivers/usb/host/ehci-hcd.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index 80cc87c9ef..2582bf36eb 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -592,8 +592,9 @@ ehci_submit_async(struct usb_device *dev, unsigned long pipe, void *buffer, * dangerous operation, it's responsibility of the calling * code to make sure enough space is reserved. */ - invalidate_dcache_range((unsigned long)buffer, - ALIGN((unsigned long)buffer + length, ARCH_DMA_MINALIGN)); + if (buffer != NULL && length > 0) + invalidate_dcache_range((unsigned long)buffer, + ALIGN((unsigned long)buffer + length, ARCH_DMA_MINALIGN)); /* Check that the TD processing happened */ if (QT_TOKEN_GET_STATUS(token) & QT_TOKEN_STATUS_ACTIVE) -- 2.39.5