On Thu, May 18, 2017 at 12:46 PM, Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > 4.11-stable review patch. If anyone has any objections, please let me know. > > ------------------ > > From: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > > commit 500fcc08a32bfd54f11951ba81530775df15c474 upstream. > > 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@xxxxxxxxxxx> > Fixes: 62c37eedb74c8 ("serial: samsung: add dma reqest/release functions") > Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx> > Reviewed-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > --- > drivers/tty/serial/samsung.c | 31 ++++++++++++++++++++++++------- > 1 file changed, 24 insertions(+), 7 deletions(-) > > --- a/drivers/tty/serial/samsung.c > +++ b/drivers/tty/serial/samsung.c > @@ -859,7 +859,7 @@ static void s3c24xx_serial_break_ctl(str > static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p) > { > struct s3c24xx_uart_dma *dma = p->dma; > - unsigned long flags; > + int ret; This does not compile: http://www.krzk.eu/#/builders/5/builds/225 It works fine in mainline because the patch 3/3 of the set was removing the user of the flags. I'll send a fixup for stable. BR, Krzysztof