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authorMarek Szyprowski <m.szyprowski@samsung.com>2017-04-03 08:21:00 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-04-08 18:58:52 +0200
commit500fcc08a32bfd54f11951ba81530775df15c474 (patch)
tree94d1be03ffa81ea230f90aebbab6395bf71378fb /drivers/tty
parent768d64f491a530062ddad50e016fb27125f8bd7c (diff)
downloadlinux-500fcc08a32bfd54f11951ba81530775df15c474.tar.bz2
serial: samsung: Add missing checks for dma_map_single failure
This patch adds missing checks for dma_map_single() failure and proper error reporting. Although this issue was harmless on ARM architecture, it is always good to use the DMA mapping API in a proper way. This patch fixes the following DMA API debug warning: WARNING: CPU: 1 PID: 3785 at lib/dma-debug.c:1171 check_unmap+0x8a0/0xf28 dma-pl330 121a0000.pdma: DMA-API: device driver failed to check map error[device address=0x000000006e0f9000] [size=4096 bytes] [mapped as single] Modules linked in: CPU: 1 PID: 3785 Comm: (agetty) Tainted: G W 4.11.0-rc1-00137-g07ca963-dirty #59 Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [<c011aaa4>] (unwind_backtrace) from [<c01127c0>] (show_stack+0x20/0x24) [<c01127c0>] (show_stack) from [<c06ba5d8>] (dump_stack+0x84/0xa0) [<c06ba5d8>] (dump_stack) from [<c0139528>] (__warn+0x14c/0x180) [<c0139528>] (__warn) from [<c01395a4>] (warn_slowpath_fmt+0x48/0x50) [<c01395a4>] (warn_slowpath_fmt) from [<c072a114>] (check_unmap+0x8a0/0xf28) [<c072a114>] (check_unmap) from [<c072a834>] (debug_dma_unmap_page+0x98/0xc8) [<c072a834>] (debug_dma_unmap_page) from [<c0803874>] (s3c24xx_serial_shutdown+0x314/0x52c) [<c0803874>] (s3c24xx_serial_shutdown) from [<c07f5124>] (uart_port_shutdown+0x54/0x88) [<c07f5124>] (uart_port_shutdown) from [<c07f522c>] (uart_shutdown+0xd4/0x110) [<c07f522c>] (uart_shutdown) from [<c07f6a8c>] (uart_hangup+0x9c/0x208) [<c07f6a8c>] (uart_hangup) from [<c07c426c>] (__tty_hangup+0x49c/0x634) [<c07c426c>] (__tty_hangup) from [<c07c78ac>] (tty_ioctl+0xc88/0x16e4) [<c07c78ac>] (tty_ioctl) from [<c03b5f2c>] (do_vfs_ioctl+0xc4/0xd10) [<c03b5f2c>] (do_vfs_ioctl) from [<c03b6bf4>] (SyS_ioctl+0x7c/0x8c) [<c03b6bf4>] (SyS_ioctl) from [<c010b4a0>] (ret_fast_syscall+0x0/0x3c) Reported-by: Seung-Woo Kim <sw0312.kim@samsung.com> Fixes: 62c37eedb74c8 ("serial: samsung: add dma reqest/release functions") CC: stable@vger.kernel.org # v4.10+ Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Reviewed-by: Shuah Khan <shuahkh@osg.samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
-rw-r--r--drivers/tty/serial/samsung.c31
1 files changed, 24 insertions, 7 deletions
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 9f3759bdb44f..ca0bcd7fd61f 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -859,7 +859,7 @@ static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
{
struct s3c24xx_uart_dma *dma = p->dma;
- unsigned long flags;
+ int ret;
/* Default slave configuration parameters */
dma->rx_conf.direction = DMA_DEV_TO_MEM;
@@ -884,8 +884,8 @@ static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
dma->tx_chan = dma_request_chan(p->port.dev, "tx");
if (IS_ERR(dma->tx_chan)) {
- dma_release_channel(dma->rx_chan);
- return PTR_ERR(dma->tx_chan);
+ ret = PTR_ERR(dma->tx_chan);
+ goto err_release_rx;
}
dmaengine_slave_config(dma->tx_chan, &dma->tx_conf);
@@ -894,15 +894,17 @@ static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
dma->rx_size = PAGE_SIZE;
dma->rx_buf = kmalloc(dma->rx_size, GFP_KERNEL);
-
if (!dma->rx_buf) {
- dma_release_channel(dma->rx_chan);
- dma_release_channel(dma->tx_chan);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto err_release_tx;
}
dma->rx_addr = dma_map_single(p->port.dev, dma->rx_buf,
dma->rx_size, DMA_FROM_DEVICE);
+ if (dma_mapping_error(p->port.dev, dma->rx_addr)) {
+ ret = -EIO;
+ goto err_free_rx;
+ }
spin_lock_irqsave(&p->port.lock, flags);
@@ -911,8 +913,23 @@ static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
UART_XMIT_SIZE, DMA_TO_DEVICE);
spin_unlock_irqrestore(&p->port.lock, flags);
+ if (dma_mapping_error(p->port.dev, dma->tx_addr)) {
+ ret = -EIO;
+ goto err_unmap_rx;
+ }
return 0;
+
+err_unmap_rx:
+ dma_unmap_single(p->port.dev, dma->rx_addr, dma->rx_size,
+ DMA_FROM_DEVICE);
+err_free_rx:
+ kfree(dma->rx_buf);
+err_release_tx:
+ dma_release_channel(dma->tx_chan);
+err_release_rx:
+ dma_release_channel(dma->rx_chan);
+ return ret;
}
static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p)