sg_alloc_table_from_pages() only allocates a sg_table, so it should just use GFP_KERNEL, not gfp_flags. If gfp_flags contains __GFP_DMA32 then mm/sl[au]b.c will call BUG_ON: [ 358.027515] ------------[ cut here ]------------ [ 358.027546] kernel BUG at mm/slub.c:1416! [ 358.027558] invalid opcode: 0000 [#1] PREEMPT SMP [ 358.027576] Modules linked in: mt2131 s5h1409 tda8290 tuner cx25840 cx23885 btcx_risc altera_ci tda18271 altera_stapl videobuf2_dvb tveeprom cx2341x videobuf2_dma_sg dvb_core rc_core videobuf2_memops videobuf2_core nouveau zr36067 videocodec v4l2_common videodev media x86_pkg_temp_thermal cfbfillrect cfbimgblt cfbcopyarea ttm drm_kms_helper processor button isci [ 358.027712] CPU: 19 PID: 3654 Comm: cat Not tainted 3.16.0-rc6-telek #167 [ 358.027723] Hardware name: ASUSTeK COMPUTER INC. Z9PE-D8 WS/Z9PE-D8 WS, BIOS 5404 02/10/2014 [ 358.027741] task: ffff880897c7d960 ti: ffff88089b4d4000 task.ti: ffff88089b4d4000 [ 358.027753] RIP: 0010:[<ffffffff81196040>] [<ffffffff81196040>] new_slab+0x280/0x320 [ 358.027776] RSP: 0018:ffff88089b4d7ae8 EFLAGS: 00010002 [ 358.027787] RAX: ffff880897c7d960 RBX: 0000000000000000 RCX: ffff88089b4d7b50 [ 358.027798] RDX: 00000000ffffffff RSI: 0000000000000004 RDI: ffff88089f803b00 [ 358.027809] RBP: ffff88089b4d7bb8 R08: 0000000000000000 R09: 0000000100400040 [ 358.027821] R10: 0000160000000000 R11: ffff88109bc02c40 R12: 0000000000000001 [ 358.027832] R13: ffff88089f8000c0 R14: ffff88089f803b00 R15: ffff8810bfcf4be0 [ 358.027845] FS: 00007f83fe5c0700(0000) GS:ffff8810bfce0000(0000) knlGS:0000000000000000 [ 358.027858] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 358.027868] CR2: 0000000001dfd568 CR3: 0000001097d5a000 CR4: 00000000000407e0 [ 358.027878] Stack: [ 358.027885] ffffffff81198860 ffff8810bfcf4be0 ffff880897c7d960 0000000000001b00 [ 358.027905] ffff880897c7d960 0000000000000000 ffff8810bfcf4bf0 0000000000000000 [ 358.027924] 0000000000000000 0000000100000100 ffffffff813ef84a 00000004ffffffff [ 358.027944] Call Trace: [ 358.027956] [<ffffffff81198860>] ? __slab_alloc+0x400/0x4e0 [ 358.027973] [<ffffffff813ef84a>] ? sg_kmalloc+0x1a/0x30 [ 358.027985] [<ffffffff81198f17>] __kmalloc+0x127/0x150 [ 358.027997] [<ffffffff813ef84a>] ? sg_kmalloc+0x1a/0x30 [ 358.028009] [<ffffffff813ef84a>] sg_kmalloc+0x1a/0x30 [ 358.028023] [<ffffffff813eff84>] __sg_alloc_table+0x74/0x180 [ 358.028035] [<ffffffff813ef830>] ? sg_kfree+0x20/0x20 [ 358.028048] [<ffffffff813f00af>] sg_alloc_table+0x1f/0x60 [ 358.028061] [<ffffffff813f0174>] sg_alloc_table_from_pages+0x84/0x1f0 [ 358.028077] [<ffffffffa007c3f9>] vb2_dma_sg_alloc+0x159/0x230 [videobuf2_dma_sg] [ 358.028095] [<ffffffffa003d55a>] __vb2_queue_alloc+0x10a/0x680 [videobuf2_core] [ 358.028113] [<ffffffffa003e110>] __reqbufs.isra.14+0x220/0x3e0 [videobuf2_core] [ 358.028130] [<ffffffffa003e79d>] __vb2_init_fileio+0xbd/0x380 [videobuf2_core] [ 358.028147] [<ffffffffa003f563>] __vb2_perform_fileio+0x5b3/0x6e0 [videobuf2_core] [ 358.028164] [<ffffffffa003f871>] vb2_fop_read+0xb1/0x100 [videobuf2_core] [ 358.028184] [<ffffffffa06dd2e5>] v4l2_read+0x65/0xb0 [videodev] [ 358.028198] [<ffffffff811a243f>] vfs_read+0x8f/0x170 [ 358.028210] [<ffffffff811a30a1>] SyS_read+0x41/0xb0 [ 358.028224] [<ffffffff818f02e9>] system_call_fastpath+0x16/0x1b [ 358.028234] Code: 66 90 e9 dc fd ff ff 0f 1f 40 00 41 8b 4d 68 e9 d5 fe ff ff 0f 1f 80 00 00 00 00 f0 41 80 4d 00 40 e9 03 ff ff ff 0f 1f 44 00 00 <0f> 0b 66 0f 1f 44 00 00 44 89 c6 4c 89 45 d0 e8 0c 82 ff ff 48 [ 358.028415] RIP [<ffffffff81196040>] new_slab+0x280/0x320 [ 358.028432] RSP <ffff88089b4d7ae8> [ 358.032208] ---[ end trace 6443240199c706e4 ]--- Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx # for v3.13 and up diff --git a/drivers/media/v4l2-core/videobuf2-dma-sg.c b/drivers/media/v4l2-core/videobuf2-dma-sg.c index adefc31..9b163a4 100644 --- a/drivers/media/v4l2-core/videobuf2-dma-sg.c +++ b/drivers/media/v4l2-core/videobuf2-dma-sg.c @@ -113,7 +113,7 @@ static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size, gfp_t gfp_fla goto fail_pages_alloc; ret = sg_alloc_table_from_pages(&buf->sg_table, buf->pages, - buf->num_pages, 0, size, gfp_flags); + buf->num_pages, 0, size, GFP_KERNEL); if (ret) goto fail_table_alloc; -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html