This fixes the following newly introduced warning: [ 15.518253] ------------[ cut here ]------------ [ 15.518941] WARNING: CPU: 0 PID: 246 at /home/matwey/lab/linux/kernel/dma/mapping.c:149 dma_map_page_attrs+0x1a8/0x1d0 [ 15.520634] Modules linked in: pwc videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_common videodev mc efivarfs [ 15.522335] CPU: 0 PID: 246 Comm: v4l2-test Not tainted 5.11.0-rc1+ #1 [ 15.523281] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 [ 15.524438] RIP: 0010:dma_map_page_attrs+0x1a8/0x1d0 [ 15.525135] Code: 10 5b 5d 41 5c 41 5d c3 4d 89 d0 eb d7 4d 89 c8 89 e9 48 89 da e8 68 29 00 00 eb d1 48 89 f2 48 2b 50 18 48 89 d0 eb 83 0f 0b <0f> 0b 48 c7 c0 ff ff ff ff eb b8 48 89 d9 48 8b 40 40 e8 61 69 d2 [ 15.527938] RSP: 0018:ffffa2694047bca8 EFLAGS: 00010246 [ 15.528716] RAX: 0000000000000000 RBX: 0000000000002580 RCX: 0000000000000000 [ 15.529782] RDX: 0000000000000000 RSI: ffffcdce000ecc00 RDI: ffffa0b4bdb888a0 [ 15.530849] RBP: 0000000000000002 R08: 0000000000000002 R09: 0000000000000000 [ 15.531881] R10: 0000000000000004 R11: 000000000002d8c0 R12: 0000000000000000 [ 15.532911] R13: ffffa0b4bdb88800 R14: ffffa0b483820000 R15: ffffa0b4bdb888a0 [ 15.533942] FS: 00007fc5fbb5e4c0(0000) GS:ffffa0b4fc000000(0000) knlGS:0000000000000000 [ 15.535141] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 15.535988] CR2: 00007fc5fb6ea138 CR3: 0000000003812000 CR4: 00000000001506f0 [ 15.537025] Call Trace: [ 15.537425] start_streaming+0x2e9/0x4b0 [pwc] [ 15.538143] vb2_start_streaming+0x5e/0x110 [videobuf2_common] [ 15.538989] vb2_core_streamon+0x107/0x140 [videobuf2_common] [ 15.539831] __video_do_ioctl+0x18f/0x4a0 [videodev] [ 15.540670] video_usercopy+0x13a/0x5b0 [videodev] [ 15.541349] ? video_put_user+0x230/0x230 [videodev] [ 15.542096] ? selinux_file_ioctl+0x143/0x200 [ 15.542752] v4l2_ioctl+0x40/0x50 [videodev] [ 15.543360] __x64_sys_ioctl+0x89/0xc0 [ 15.543930] do_syscall_64+0x33/0x40 [ 15.544448] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 15.545236] RIP: 0033:0x7fc5fb671587 [ 15.545780] Code: b3 66 90 48 8b 05 11 49 2c 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 48 2c 00 f7 d8 64 89 01 48 [ 15.548486] RSP: 002b:00007fff0f71f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 15.549578] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fc5fb671587 [ 15.550664] RDX: 00007fff0f71f060 RSI: 0000000040045612 RDI: 0000000000000003 [ 15.551706] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 15.552738] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff0f71f060 [ 15.553817] R13: 00007fff0f71f1d0 R14: 0000000000de1270 R15: 0000000000000000 [ 15.554914] ---[ end trace 7be03122966c2486 ]--- Fixes: 1161db6776bd ("media: usb: pwc: Don't use coherent DMA buffers for ISO transfer") Signed-off-by: Matwey V. Kornilov <matwey@xxxxxxxxxx> --- drivers/media/usb/pwc/pwc-if.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/drivers/media/usb/pwc/pwc-if.c b/drivers/media/usb/pwc/pwc-if.c index 61869636ec61..5e3339cc31c0 100644 --- a/drivers/media/usb/pwc/pwc-if.c +++ b/drivers/media/usb/pwc/pwc-if.c @@ -155,16 +155,17 @@ static const struct video_device pwc_template = { /***************************************************************************/ /* Private functions */ -static void *pwc_alloc_urb_buffer(struct device *dev, +static void *pwc_alloc_urb_buffer(struct usb_device *dev, size_t size, dma_addr_t *dma_handle) { + struct device *dmadev = dev->bus->sysdev; void *buffer = kmalloc(size, GFP_KERNEL); if (!buffer) return NULL; - *dma_handle = dma_map_single(dev, buffer, size, DMA_FROM_DEVICE); - if (dma_mapping_error(dev, *dma_handle)) { + *dma_handle = dma_map_single(dmadev, buffer, size, DMA_FROM_DEVICE); + if (dma_mapping_error(dmadev, *dma_handle)) { kfree(buffer); return NULL; } @@ -172,12 +173,14 @@ static void *pwc_alloc_urb_buffer(struct device *dev, return buffer; } -static void pwc_free_urb_buffer(struct device *dev, +static void pwc_free_urb_buffer(struct usb_device *dev, size_t size, void *buffer, dma_addr_t dma_handle) { - dma_unmap_single(dev, dma_handle, size, DMA_FROM_DEVICE); + struct device *dmadev = dev->bus->sysdev; + + dma_unmap_single(dmadev, dma_handle, size, DMA_FROM_DEVICE); kfree(buffer); } @@ -282,6 +285,7 @@ static void pwc_frame_complete(struct pwc_device *pdev) static void pwc_isoc_handler(struct urb *urb) { struct pwc_device *pdev = (struct pwc_device *)urb->context; + struct device *dmadev = urb->dev->bus->sysdev; int i, fst, flen; unsigned char *iso_buf = NULL; @@ -328,7 +332,7 @@ static void pwc_isoc_handler(struct urb *urb) /* Reset ISOC error counter. We did get here, after all. */ pdev->visoc_errors = 0; - dma_sync_single_for_cpu(&urb->dev->dev, + dma_sync_single_for_cpu(dmadev, urb->transfer_dma, urb->transfer_buffer_length, DMA_FROM_DEVICE); @@ -379,7 +383,7 @@ static void pwc_isoc_handler(struct urb *urb) pdev->vlast_packet_size = flen; } - dma_sync_single_for_device(&urb->dev->dev, + dma_sync_single_for_device(dmadev, urb->transfer_dma, urb->transfer_buffer_length, DMA_FROM_DEVICE); @@ -461,7 +465,7 @@ static int pwc_isoc_init(struct pwc_device *pdev) urb->pipe = usb_rcvisocpipe(udev, pdev->vendpoint); urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; urb->transfer_buffer_length = ISO_BUFFER_SIZE; - urb->transfer_buffer = pwc_alloc_urb_buffer(&udev->dev, + urb->transfer_buffer = pwc_alloc_urb_buffer(udev, urb->transfer_buffer_length, &urb->transfer_dma); if (urb->transfer_buffer == NULL) { @@ -524,7 +528,7 @@ static void pwc_iso_free(struct pwc_device *pdev) if (urb) { PWC_DEBUG_MEMORY("Freeing URB\n"); if (urb->transfer_buffer) - pwc_free_urb_buffer(&urb->dev->dev, + pwc_free_urb_buffer(urb->dev, urb->transfer_buffer_length, urb->transfer_buffer, urb->transfer_dma); -- 2.26.2