[PATCH 4.19 24/31] misc: rtsx_usb: fix use of dma mapped buffer for usb bulk transfer

Greg Kroah-Hartman
2022-07-11T09:12:30Z

From: Shuah Khan <skhan@linuxfoundation.org>

commit eb7f8e28420372787933eec079735c35034bda7d upstream.

rtsx_usb driver allocates coherent dma buffer for urb transfers.
This buffer is passed to usb_bulk_msg() and usb core tries to
map already mapped buffer running into a dma mapping error.

xhci_hcd 0000:01:00.0: rejecting DMA map of vmalloc memory
WARNING: CPU: 1 PID: 279 at include/linux/dma-mapping.h:326 usb_ hcd_map_urb_for_dma+0x7d6/0x820

...

xhci_map_urb_for_dma+0x291/0x4e0
usb_hcd_submit_urb+0x199/0x12b0
...
usb_submit_urb+0x3b8/0x9e0
usb_start_wait_urb+0xe3/0x2d0
usb_bulk_msg+0x115/0x240
rtsx_usb_transfer_data+0x185/0x1a8 [rtsx_usb]
rtsx_usb_send_cmd+0xbb/0x123 [rtsx_usb]
rtsx_usb_write_register+0x12c/0x143 [rtsx_usb]
rtsx_usb_probe+0x226/0x4b2 [rtsx_usb]

Fix it to use kmalloc() to get DMA-able memory region instead.

Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/667d627d502e1ba9ff4f9b94966df3299d2d3c0d.1656642167.git.skhan@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/misc/cardreader/rtsx_usb.c | 13 +++++++------
include/linux/rtsx_usb.h | 1 -
2 files changed, 7 insertions(+), 7 deletions(-)

--- a/drivers/misc/cardreader/rtsx_usb.c
+++ b/drivers/misc/cardreader/rtsx_usb.c
@@ -642,8 +642,7 @@ static int rtsx_usb_probe(struct usb_int

ucr->pusb_dev = usb_dev;

- ucr->iobuf = usb_alloc_coherent(ucr->pusb_dev, IOBUF_SIZE,
- GFP_KERNEL, &ucr->iobuf_dma);
+ ucr->iobuf = kmalloc(IOBUF_SIZE, GFP_KERNEL);
if (!ucr->iobuf)
return -ENOMEM;

@@ -679,8 +678,9 @@ static int rtsx_usb_probe(struct usb_int

out_init_fail:
usb_set_intfdata(ucr->pusb_intf, NULL);
- usb_free_coherent(ucr->pusb_dev, IOBUF_SIZE, ucr->iobuf,
- ucr->iobuf_dma);
+ kfree(ucr->iobuf);
+ ucr->iobuf = NULL;
+ ucr->cmd_buf = ucr->rsp_buf = NULL;
return ret;
}

@@ -693,8 +693,9 @@ static void rtsx_usb_disconnect(struct u
mfd_remove_devices(&intf->dev);

usb_set_intfdata(ucr->pusb_intf, NULL);
- usb_free_coherent(ucr->pusb_dev, IOBUF_SIZE, ucr->iobuf,
- ucr->iobuf_dma);
+ kfree(ucr->iobuf);
+ ucr->iobuf = NULL;
+ ucr->cmd_buf = ucr->rsp_buf = NULL;
}

#ifdef CONFIG_PM
--- a/include/linux/rtsx_usb.h
+++ b/include/linux/rtsx_usb.h
@@ -66,7 +66,6 @@ struct rtsx_ucr {
struct usb_interface *pusb_intf;
struct usb_sg_request current_sg;
unsigned char *iobuf;
- dma_addr_t iobuf_dma;

struct timer_list sg_timer;
struct mutex dev_mutex;