MacOS(Apple Silicon) IOKit driver for FPGA DMA transmission, kernel panic.
Hardware and software configuration: MAC mini M1 2020 16GB, macOS Ventura 13.0 or 13.7.8 FPGA device capability: 64-bit
Complete description: We've developed a DMA driver for PCIe devices (FPGA) based on IOKit. The driver can start normally through kextload, and the bar mapping, DMA registers, etc. are all correct. I am testing DMA data transmission, but a kernel panic has occurred. The specific content of the panic is as follows: {"bug_type":"210","timestamp":"2026-01-28 14:35:30.00 +0800","os_version":"macOS 13.0 (22A380)","roots_installed":0,"incident_id":"61C9B820-8D1B-4E75-A4EB-10DC2558FA75"} { "build" : "macOS 13.0 (22A380)", "product" : "Macmini9,1", "socId" : "0x00008103", "kernel" : "Darwin Kernel Version 22.1.0: Sun Oct 9 20:14:30 PDT 2022; root:xnu-8792.41.9~2/RELEASE_ARM64_T8103", "incident" : "61C9B820-8D1B-4E75-A4EB-10DC2558FA75", "crashReporterKey" : "6435F6BD-4138-412A-5142-83DD7E5B4F61", "date" : "2026-01-28 14:35:30.16 +0800",
"panicString" : "panic(cpu 0 caller 0xfffffe0026c78c2c): "apciec[pcic0-bridge]::handleInterrupt: Request address is greater than 32 bits linksts=0x99000001 pcielint=0x02220060 linkcdmsts=0x00000000 (ltssm 0x11=L0)\n" @AppleT8103PCIeCPort.cpp:1301\nDebugger message: panic\nMemory ID: 0x6\nOS release type: User\nOS version: 22A380\nKernel version: Darwin Kernel Version 22.1.0: Sun Oct 9 20:14:30 PDT 2022; root:xnu-8792.41.9~2/RELEASE_ARM64_T8103\nFileset Kernelcache UUID: C222B4132B9708E5E0E2E8B8C5896410\nKernel UUID: 0BFE6A5D-118B-3889-AE2B-D34A0117A062\nBoot session UUID: 61C9B820-8D1B-4E75-A4EB-10DC2558FA75\niBoot version: iBoot-8419.41.10\nsecure boot?: YES\nroots installed: 0\nPaniclog version: 14\nKernelCache slide: 0x000000001d1b4000\nKernelCache base: 0xfffffe00241b8000\nKernel slide: 0x000000001e3f8000\nKernel text base: 0xfffffe00253fc000\nKernel text exec slide: 0x000000001e4e0000\nKernel text exec base: 0xfffffe00254e4000\nmach_absolute_time: 0x907c3082\nEpoch Time: sec usec\n Boot : 0x6979adbb 0x00023a6a\n Sleep : 0x00000000 0x00000000\n Wake : 0x00000000 0x00000000\n Calendar: 0x6979ae1a 0x00064953\n\nZone info:\n Zone map: 0xfffffe1000834000 - 0xfffffe3000834000\n . VM : 0xfffffe1000834000 - 0xfffffe14cd500000\n . RO : 0xfffffe14cd500000 - 0xfffffe1666e98000\n . GEN0 : 0xfffffe1666e98000 - 0xfffffe1b33b64000\n . GEN1 : 0xfffffe1b33b64000 - 0xfffffe2000830000\n . GEN2 : 0xfffffe2000830000 - 0xfffffe24cd4fc000\n . GEN3 : 0xfffffe24cd4fc000 - 0xfffffe299a1c8000\n . DATA : 0xfffffe299a1c8000 - 0xfffffe3000834000\n Metadata: 0xfffffe3f4d1ac000 - 0xfffffe3f551ac000\n Bitmaps : 0xfffffe3f551ac000 - 0xfffffe3f5ac94000\n\nCORE 0 recently retired instr at 0xfffffe002569d7a0\nCORE 1 recently retired instr at 0xfffffe002569eea0\nCORE 2 recently retired instr at 0xfffffe002569eea0\nCORE 3 recently retired instr at 0xfffffe002569eea0\nCORE 4 recently retired instr at 0xfffffe002569eea0\nCORE 5 recently retired instr at 0xfffffe002569eea0\nCORE 6 recently retired instr at 0xfffffe002569eea0\nCORE 7 recently retired instr at 0xfffffe002569eea0\nTPIDRx_ELy = {1: 0xfffffe2000c23010 0: 0x0000000000000000 0ro: 0x0000000000000000 }\nCORE 0 PVH locks held: None\nCORE 1 PVH locks held: None\nCORE 2 PVH locks held: None\nCORE 3 PVH locks held: None\nCORE 4 PVH locks held: None\nCORE 5 PVH locks held: None\nCORE 6 PVH locks held: None\nCORE 7 PVH locks held: None\nCORE 0 is the one that panicked. Check the full backtrace for details.\nCORE 1: PC=0xfffffe00279db94c, LR=0xfffffe00260d5d9c, FP=0xfffffe8ffecaf850\nCORE 2: PC=0xfffffe0025be76b0, LR=0xfffffe0025be7628, FP=0xfffffe8fff08f5f0\nCORE 3: PC=0x00000001c7cacd78, LR=0x00000001c7cacd84, FP=0x000000016f485130\nCORE 4: PC=0xfffffe002557f55c, LR=0xfffffe002557f55c, FP=0xfffffe8ffe1dff00\nCORE 5: PC=0xfffffe002557f55c, LR=0xfffffe002557f55c, FP=0xfffffe8fff5eff00\nCORE 6: PC=0xfffffe002557f55c, LR=0xfffffe002557f55c, FP=0xfffffe8ffed8bf00\nCORE 7: PC=0xfffffe002557f55c, LR=0xfffffe002557f55c, FP=0xfffffe8fff11bf00\nCompressor Info: 0% of compressed pages limit (OK) and 0% of segments limit (OK) with 0 swapfiles and OK swap space\nPanicked task 0xfffffe1b33aad678: 0 pages, 470 threads: pid 0: kernel_task\nPanicked thread: 0xfffffe2000c23010, backtrace: 0xfffffe8fff6eb6a0, tid: 265\n\t\t ...
Kernel Extensions in backtrace:\n com.apple.driver.AppleT8103PCIeC(1.0)[A595D104-026A-39E5-93AA-4C87CE8C14D2]@0xfffffe0026c619d0->0xfffffe0026c86c97\n dependency: com.apple.driver.AppleARMPlatform(1.0.2)[11A9713E-6739-3A4C-8571-2D8EAA062278]@0xfffffe0025f13ff0->0xfffffe0025f6255f\n dependency: com.apple.driver.AppleEmbeddedPCIE(1)[E71CBCCD-AEB8-3E7B-933D-4FED4241BF13]@0xfffffe002654e0b0->0xfffffe00265684c7\n dependency: com.apple.driver.ApplePIODMA(1)[A419BABC-A7A3-316D-A150-7C2C2D1F6D53]@0xfffffe00269a24b0->0xfffffe00269a6c3b\n dependency: com.apple.driver.IODARTFamily(1)[03997E20-8A3F-3412-A4E8-BD968A75A07D]@0xfffffe00275bcf50->0xfffffe00275d0a3f\n dependency: com.apple.iokit.IOPCIFamily(2.9)[EC78F47B-530B-3F87-854E-0A0A5FD9BBB2]@0xfffffe0027934350->0xfffffe002795f3d3\n dependency: com.apple.iokit.IOReportFamily(47)[843B39D3-146E-3992-B7C7-960148685DC8]@0xfffffe0027963010->0xfffffe0027965ffb\n dependency: com.apple.iokit.IOThunderboltFamily(9.3.3)[B22BC005-BB7B-32A3-99C0-39F3BDBD8E54]@0xfffffe0027a5e3f0->0xfffffe0027b9a1a3\n\nlast started kext at 1915345919: com.sobb.pcie-dma\t1.0.0d1 (addr 0xfffffe00240e47f0, size 9580)\nlast stopped kext at 1774866338: com.sobb.pcie-dma\t1.0.0d1 (addr 0xfffffe00240e47f0, size 9580)\nloaded
It seems that the DMA request address initiated by FPGA exceeded 32 bits, which was intercepted by PCIe root port and resulted in a kernel panic.This is also the case on macOS (M2).
I have tried the following code interface: IOBufferMemoryDescriptor： a. withCapacity(bufferSize, kIODirectionInOut, true)； b. inTaskWithPhysicalMask(kernel_task, kIODirectionInOut, bufferSize, 0x00000000FFFFFFFFULL)。 The physical addresses of the constructed descriptors are all >32 bits; IODMACommand： a. withSpecification(kIODMACommandOutputHost64, 64, 0, IODMACommand::kMapped, 0, 0)，gen64IOVMSegments() The allocated IOVM address must be>32 bits, which will generate a kernel panic when used later. b.withSpecification(kIODMACommandOutputHost32, 32, 0, IODMACommand::kMapped, 0, 0)，gen32IOVMSegments() The allocation of IOVM failed with error code kIOReturnenMessageTooLarge.
So after the above attempts, the analysis shows that the strategy of Dart+PCIe root port on macOS (Apple Silicon) is causing the failure of 64 bit DMA address transfer.
I have two questions: a. Does Dart in macOS (Apple Silicon) definitely not allocate <=32-bit IOVM addresses? b. Is there any other way to achieve DMA transfer for FGPA devices on macOS (Apple Silicon)?
Thanks！