Windows 10: DMA Remapping

PLease explin in simple terms what is DMA remapping and does it have anything to do with online purchase protection?Kennth

:)

 

Dma ?

On my sys. (sys. listed), how do I enable or disable DMA on my Sata drives? I have a Sumsung SH-S203b Dvd recorder (sata) and in the Nero info tool I get a warning that DMA is disabled on this drive. On my old sys. (P4C800-E Deluxe) the Intel raid driver software provided control of dma. On the P5K Deluxe where do I find the drive settings (DMA or PIO) and how would I change them?

Thank You.

 

Enabled the "DMA remapping" for my device driver but I still get the "IOMMU detected DMA violation" error

Hi,

I have enabled the DMA remapping for my device driver but I still get the "IOMMU detected DMA violation" error whenever I try to perform any DMA transactions on my PCI device connected via Thunderbolt 3.

I have updated the UEFI firmware. The DMA Kernel Protection is ON.

The driver shows "DMA remapping policy" enabled.

Also, set the group policy 'Disable new DMA devices when this computer is locked' for the BitLocker to "Disabled".

Driver Verifier is running.

Any idea why still get the error DRIVER_VERIFIER_DMA_VIOLATION? The device get enumerated but it fails on DMA operations. Curiously enough, I thought I wouldn't be able to access to my device only when the system was asleep AND my device driver was not compatible with DMA remapping? Otherwise it should function normally according to this:

"By default, peripherals with DMA Remapping incompatible drivers will be blocked from starting and performing DMA until an authorized user signs into the system or unlocks the screen."

Any idea what's going on?

Thanks,

MJ

PS.

FYI:



Microsoft (R) Windows Debugger Version 10.0.22000.194 AMD64

Copyright (c) Microsoft Corporation. All rights reserved.





Loading Dump File [C:\Windows\MEMORY.DMP]

Kernel Bitmap Dump File: Kernel address space is available, User address space may not be available.



Symbol search path is: srv*

Executable search path is:

Windows 10 Kernel Version 19041 MP (8 procs) Free x64

Product: WinNt, suite: TerminalServer SingleUserTS

Edition build lab: 19041.1.amd64fre.vb_release.191206-1406

Machine Name:

Kernel base = 0xfffff802`5fe00000 PsLoadedModuleList = 0xfffff802`60a2a2d0

Debug session time: Wed Dec 1 16:59:57.956 2021 (UTC + 0:00)

System Uptime: 0 days 0:02:25.818

Loading Kernel Symbols

...............................................................

................................................................

................................................................

........................................

Loading User Symbols



Loading unloaded module list

.............................

For analysis of this file, run !analyze -v

0: kd> !analyze -v

*******************************************************************************

* *

* Bugcheck Analysis *

* *

*******************************************************************************



DRIVER_VERIFIER_DMA_VIOLATION (e6)

An illegal DMA operation was attempted by a driver being verified.

Arguments:

Arg1: 0000000000000026, IOMMU detected DMA violation.

Arg2: 0000000000000000, Device Object of faulting device.

Arg3: 0000000000000001, Faulting information (usually faulting physical address).

Arg4: 0000000000000006, Fault type (hardware specific).



Debugging Details:

------------------





KEY_VALUES_STRING: 1



Key : Analysis.CPU.mSec

Value: 3327



Key : Analysis.DebugAnalysisManager

Value: Create



Key : Analysis.Elapsed.mSec

Value: 3334



Key : Analysis.Init.CPU.mSec

Value: 3187



Key : Analysis.Init.Elapsed.mSec

Value: 312916



Key : Analysis.Memory.CommitPeak.Mb

Value: 82



Key : WER.OS.Branch

Value: vb_release



Key : WER.OS.Timestamp

Value: 2019-12-06T14:06:00Z



Key : WER.OS.Version

Value: 10.0.19041.1





BUGCHECK_CODE: e6



BUGCHECK_P1: 26



BUGCHECK_P2: 0



BUGCHECK_P3: 1



BUGCHECK_P4: 6



BLACKBOXBSD: 1 (!blackboxbsd)





BLACKBOXNTFS: 1 (!blackboxntfs)





BLACKBOXPNP: 1 (!blackboxpnp)





BLACKBOXWINLOGON: 1



PROCESS_NAME: System



STACK_TEXT:

fffff802`630a1ea8 fffff802`602db447 : 00000000`000000e6 00000000`00000026 00000000`00000000 00000000`00000001 : nt!KeBugCheckEx

fffff802`630a1eb0 fffff802`602c730b : 00000000`00000000 00000000`00000000 fffff802`60a49cf0 fffff802`60a49cf0 : nt!IvtHandleInterrupt+0x1a7

fffff802`630a1f10 fffff802`600de055 : fffff802`60af3bc0 fffff802`63092a50 fffff802`60af3c70 fffff802`630a1fc0 : nt!HalpIommuInterruptRoutine+0x4b

fffff802`630a1f40 fffff802`601f8c1c : fffff802`63092a50 fffff802`60af3bc0 00000000`00000ec4 fffff802`601fdf90 : nt!KiCallInterruptServiceRoutine+0xa5

fffff802`630a1f90 fffff802`601f9027 : fffff802`63092af0 00000000`00000001 00000000`00040046 fffff802`60017138 : nt!KiInterruptSubDispatchNoLock+0x11c

fffff802`630929d0 fffff802`601fadca : 00000000`00000000 fffff802`60b27a00 ffffdf05`78106080 00000000`00000ec4 : nt!KiInterruptDispatchNoLock+0x37

fffff802`63092b60 00000000`00000000 : fffff802`63093000 fffff802`6308c000 00000000`00000000 00000000`00000000 : nt!KiIdleLoop+0x5a





SYMBOL_NAME: nt!IvtHandleInterrupt+1a7



MODULE_NAME: nt



IMAGE_NAME: ntkrnlmp.exe



STACK_COMMAND: .thread ; .cxr ; kb



BUCKET_ID_FUNC_OFFSET: 1a7



FAILURE_BUCKET_ID: 0xE6_nt!IvtHandleInterrupt



OS_VERSION: 10.0.19041.1



BUILDLAB_STR: vb_release



OSPLATFORM_TYPE: x64



OSNAME: Windows 10



FAILURE_ID_HASH: {2cafa897-b47c-7b20-cee6-b1b68f30ec38}



Followup: MachineOwner

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DMA Devices?

When I go to "System Information" and expand the "Hardware Resources" tab and then click "DMA" (Direct Memory Access), the panel that lists the devices is blank, i.e. no devices are shown.

Since my hdd, ssd, NIC, sound card etc. normally are supposed to use DMA, I'm not sure why I'm not seeing them listed.

I checked Device Manager but there doesn't appear to be any way to verify if DMA is being utilized. I recall in prior versions of Windows, Device Manager would display a check box in one of the tabs for a specific device, that would indicate if DMA was active, but I don't see this feature in Windows 10.

Is there any other way to verify whether or not devices on my computer are utilizing DMA?

Thanks.

Bob