linux/drivers/dma, branch v3.13

drivers/dma/ioat/dma.c: check DMA mapping error in ioat_dma_self_test()

2014-01-02T22:40:30Z

Check DMA mapping return values in function ioat_dma_self_test() to get rid of following warning message. ------------[ cut here ]------------ WARNING: CPU: 0 PID: 1203 at lib/dma-debug.c:937 check_unmap+0x4c0/0x9a0() ioatdma 0000:00:04.0: DMA-API: device driver failed to check map error[device address=0x000000085191b000] [size=2000 bytes] [mapped as single] Modules linked in: ioatdma(+) mac_hid wmi acpi_pad lp parport hidd_generic usbhid hid ixgbe isci dca libsas ahci ptp libahci scsi_transport_sas meegaraid_sas pps_core mdio CPU: 0 PID: 1203 Comm: systemd-udevd Not tainted 3.13.0-rc4+ #8 Hardware name: Intel Corporation BRICKLAND/BRICKLAND, BIOS BRIVTIIN1.86B.0044.L09.1311181644 11/18/2013 Call Trace: dump_stack+0x4d/0x66 warn_slowpath_common+0x7d/0xa0 warn_slowpath_fmt+0x4c/0x50 check_unmap+0x4c0/0x9a0 debug_dma_unmap_page+0x81/0x90 ioat_dma_self_test+0x3d2/0x680 [ioatdma] ioat3_dma_self_test+0x12/0x30 [ioatdma] ioat_probe+0xf4/0x110 [ioatdma] ioat3_dma_probe+0x268/0x410 [ioatdma] ioat_pci_probe+0x122/0x1b0 [ioatdma] local_pci_probe+0x45/0xa0 pci_device_probe+0xd9/0x130 driver_probe_device+0x171/0x490 __driver_attach+0x93/0xa0 bus_for_each_dev+0x6b/0xb0 driver_attach+0x1e/0x20 bus_add_driver+0x1f8/0x2b0 driver_register+0x81/0x110 __pci_register_driver+0x60/0x70 ioat_init_module+0x89/0x1000 [ioatdma] do_one_initcall+0xe2/0x250 load_module+0x2313/0x2a00 SyS_init_module+0xd9/0x130 system_call_fastpath+0x1a/0x1f ---[ end trace 990c591681d27c31 ]--- Mapped at: debug_dma_map_page+0xbe/0x180 ioat_dma_self_test+0x1ab/0x680 [ioatdma] ioat3_dma_self_test+0x12/0x30 [ioatdma] ioat_probe+0xf4/0x110 [ioatdma] ioat3_dma_probe+0x268/0x410 [ioatdma] Signed-off-by: Jiang Liu Cc: Vinod Koul Cc: Dan Williams Cc: Bartlomiej Zolnierkiewicz Cc: Kyungmin Park Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

net_dma: mark broken

2013-12-18T20:53:43Z

net_dma can cause data to be copied to a stale mapping if a copy-on-write fault occurs during dma. The application sees missing data. The following trace is triggered by modifying the kernel to WARN if it ever triggers copy-on-write on a page that is undergoing dma: WARNING: CPU: 24 PID: 2529 at lib/dma-debug.c:485 debug_dma_assert_idle+0xd2/0x120() ioatdma 0000:00:04.0: DMA-API: cpu touching an active dma mapped page [pfn=0x16bcd9] Modules linked in: iTCO_wdt iTCO_vendor_support ioatdma lpc_ich pcspkr dca CPU: 24 PID: 2529 Comm: linbug Tainted: G W 3.13.0-rc1+ #353 00000000000001e5 ffff88016f45f688 ffffffff81751041 ffff88017ab0ef70 ffff88016f45f6d8 ffff88016f45f6c8 ffffffff8104ed9c ffffffff810f3646 ffff8801768f4840 0000000000000282 ffff88016f6cca10 00007fa2bb699349 Call Trace: [] dump_stack+0x46/0x58 [] warn_slowpath_common+0x8c/0xc0 [] ? ftrace_pid_func+0x26/0x30 [] warn_slowpath_fmt+0x46/0x50 [] debug_dma_assert_idle+0xd2/0x120 [] do_wp_page+0xd0/0x790 [] handle_mm_fault+0x51c/0xde0 [] ? copy_user_enhanced_fast_string+0x9/0x20 [] __do_page_fault+0x19c/0x530 [] ? _raw_spin_lock_bh+0x16/0x40 [] ? trace_clock_local+0x9/0x10 [] ? rb_reserve_next_event+0x64/0x310 [] ? ioat2_dma_prep_memcpy_lock+0x60/0x130 [ioatdma] [] do_page_fault+0xe/0x10 [] page_fault+0x22/0x30 [] ? __kfree_skb+0x51/0xd0 [] ? copy_user_enhanced_fast_string+0x9/0x20 [] ? memcpy_toiovec+0x52/0xa0 [] skb_copy_datagram_iovec+0x5f/0x2a0 [] tcp_rcv_established+0x674/0x7f0 [] tcp_v4_do_rcv+0x2e5/0x4a0 [..] ---[ end trace e30e3b01191b7617 ]--- Mapped at: [] debug_dma_map_page+0xb9/0x160 [] dma_async_memcpy_pg_to_pg+0x127/0x210 [] dma_memcpy_pg_to_iovec+0x119/0x1f0 [] dma_skb_copy_datagram_iovec+0x11c/0x2b0 [] tcp_rcv_established+0x74a/0x7f0: ...the problem is that the receive path falls back to cpu-copy in several locations and this trace is just one of the areas. A few options were considered to fix this: 1/ sync all dma whenever a cpu copy branch is taken 2/ modify the page fault handler to hold off while dma is in-flight Option 1 adds yet more cpu overhead to an "offload" that struggles to compete with cpu-copy. Option 2 adds checks for behavior that is already documented as broken when using get_user_pages(). At a minimum a debug mode is warranted to catch and flag these violations of the dma-api vs get_user_pages(). Thanks to David for his reproducer. Cc: Cc: Dave Jiang Cc: Vinod Koul Cc: Alexander Duyck Reported-by: David Whipple Acked-by: David S. Miller Signed-off-by: Dan Williams

dma: pl330: ensure DMA descriptors are zero-initialised

2013-12-18T18:08:56Z

I see the following splat with 3.13-rc1 when attempting to perform DMA: [ 253.004516] Alignment trap: not handling instruction e1902f9f at [] [ 253.004583] Unhandled fault: alignment exception (0x221) at 0xdfdfdfd7 [ 253.004646] Internal error: : 221 [#1] PREEMPT SMP ARM [ 253.004691] Modules linked in: dmatest(+) [last unloaded: dmatest] [ 253.004798] CPU: 0 PID: 671 Comm: kthreadd Not tainted 3.13.0-rc1+ #2 [ 253.004864] task: df9b0900 ti: df03e000 task.ti: df03e000 [ 253.004937] PC is at dmaengine_unmap_put+0x14/0x34 [ 253.005010] LR is at pl330_tasklet+0x3c8/0x550 [ 253.005087] pc : [] lr : [] psr: a00e0193 [ 253.005087] sp : df03fe48 ip : 00000000 fp : df03bf18 [ 253.005178] r10: bf00e108 r9 : 00000001 r8 : 00000000 [ 253.005245] r7 : df837040 r6 : dfb41800 r5 : df837048 r4 : df837000 [ 253.005316] r3 : dfdfdfcf r2 : dfb41f80 r1 : df837048 r0 : dfdfdfd7 [ 253.005384] Flags: NzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel [ 253.005459] Control: 30c5387d Table: 9fb9ba80 DAC: fffffffd [ 253.005520] Process kthreadd (pid: 671, stack limit = 0xdf03e248) This is due to desc->txd.unmap containing garbage (uninitialised memory). Rather than add another dummy initialisation to _init_desc, instead ensure that the descriptors are zero-initialised during allocation and remove the dummy, per-field initialisation. Cc: Andriy Shevchenko Acked-by: Jassi Brar Signed-off-by: Will Deacon Acked-by: Vinod Koul Signed-off-by: Dan Williams

dmaengine: fix sleep in atomic

2013-12-13T08:57:03Z

BUG: sleeping function called from invalid context at mm/mempool.c:203 in_atomic(): 1, irqs_disabled(): 0, pid: 43502, name: linbug no locks held by linbug/43502. CPU: 7 PID: 43502 Comm: linbug Not tainted 3.13.0-rc1+ #15 Hardware name: 0000000000000010 ffff88005ebd1878 ffffffff8172d512 ffff8801752bc1c0 ffff8801752bc1c0 ffff88005ebd1898 ffffffff8109d1f6 ffff88005f9a3c58 ffff880177f0f080 ffff88005ebd1918 ffffffff81161f43 ffff88005ebd18f8 Call Trace: [] dump_stack+0x4e/0x68 [] __might_sleep+0xe6/0x120 [] mempool_alloc+0x93/0x170 [] ? mark_held_locks+0x74/0x140 [] ? follow_page_mask+0x556/0x600 [] dmaengine_get_unmap_data+0x2e/0x60 [] dma_async_memcpy_pg_to_pg+0x41/0x1c0 [] dma_async_memcpy_buf_to_pg+0x50/0x60 [] dma_memcpy_to_iovec+0xfc/0x190 [] dma_skb_copy_datagram_iovec+0x6f/0x2b0 Signed-off-by: Dan Williams

dmaengine: mv_xor: fix oops when channels fail to initialise

2013-12-13T06:48:53Z

When a channel fails to initialise, we error out and clean up any previously unregistered channels by walking the entire xordev->channels array. Unfortunately, there are paths which end up storing an error pointer in this array, which we then try and dereference in the cleanup code, which causes an oops. Fix this by avoiding writing invalid pointers to this array in the first place. Tested-by: Aaro Koskinen Signed-off-by: Russell King Signed-off-by: Dan Williams

dma: mv_xor: Use dmaengine_unmap_data for the self-tests

2013-12-13T06:48:53Z

The driver-specific unmap code was removed in: commit 54f8d501e842879143e867e70996574a54d1e130 Author: Bartlomiej Zolnierkiewicz Date: Fri Oct 18 19:35:32 2013 +0200 dmaengine: remove DMA unmap from drivers which had the side-effect of not unmapping the self-test mappings. Fix this by using dmaengine_unmap_data in the self-test routines. In addition, since dmaengine_unmap() assumes that all mappings were created with dma_map_page, this commit changes the single mapping to a page mapping to avoid an incorrect unmapping of the memcpy self-test. The allocation could be changed to be alloc_page(), but sticking to kmalloc results in a less intrusive patch. The size of the test buffer is increased, since dma_map_page() seem to fail when the source and destination pages are the same page. Signed-off-by: Ezequiel Garcia Signed-off-by: Dan Williams

dmaengine: fix enable for high order unmap pools

2013-12-13T06:43:42Z

The higher order mempools support raid operations, and we want to disable them when raid support is not enabled. Making them conditional on ASYNC_TX_DMA is not sufficient as other users (specifically dmatest) will also issue raid operations. Make raid drivers explicitly request that the core carry the higher order pools. Reported-by: Ezequiel Garcia Tested-by: Ezequiel Garcia Signed-off-by: Dan Williams

dma: fix build warnings in txx9

2013-12-13T06:43:41Z

The unmap rework missed this: drivers/dma/txx9dmac.c:409:25: warning: unused variable 'ds' [-Wunused-variable] Cc: Bartlomiej Zolnierkiewicz Signed-off-by: Dan Williams

dmatest: fix build warning on mips

2013-12-13T06:43:41Z

drivers/dma/dmatest.c:543:11: warning: passing argument 1 of 'virt_to_phys' makes pointer from integer without a cast [enabled by default] mips expects virt_to_phys() to take a pointer. Fix up the types accordingly. Signed-off-by: Dan Williams

dma: fix fsldma build warnings

2013-12-13T06:43:41Z

drivers/dma/fsldma.c: In function 'fsldma_cleanup_descriptor': drivers/dma/fsldma.c:860:6: warning: unused variable 'len' [-Wunused-variable] drivers/dma/fsldma.c:859:13: warning: unused variable 'dst' [-Wunused-variable] drivers/dma/fsldma.c:858:13: warning: unused variable 'src' [-Wunused-variable] drivers/dma/fsldma.c:857:17: warning: unused variable 'dev' [-Wunused-variable] - due to unmap changes drivers/dma/fsldma.c: In function 'fsl_dma_tx_submit': drivers/dma/fsldma.c:428:2: warning: 'cookie' may be used uninitialized in this function [-Wuninitialized] - long standing warning Cc: Bartlomiej Zolnierkiewicz Cc: Li Yang Cc: Zhang Wei Signed-off-by: Dan Williams