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How to sign a DEXT
Kevin's Guide to DEXT Signing The question of "How do I sign a DEXT" comes up a lot, so this post is my attempt to describe both what the issue are and the best current solutions are. So... The Problems: When DEXTs were originally introduced, the recommended development signing process required disabling SIP and local signing. There is a newer, much simpler process that's built on Xcode's integrated code-signing support; however, that newer process has not yet been integrated into the documentation library. In addition, while the older flow still works, many of the details it describes are no longer correct due to changes to Xcode and the developer portal. DriverKit's use of individually customized entitlements is different than the other entitlements on our platform, and Xcode's support for it is somewhat incomplete and buggy. The situation has improved considerably over time, particularly from Xcode 15 and Xcode 16, but there are still issues that are not fully resolved. To address #1, we introduced "development" entitlement variants of all DriverKit entitlements. These entitlement variants are ONLY available in development-signed builds, but they're available on all paid developer accounts without any special approval. They also allow a DEXT to match against any hardware, greatly simplifying working with development or prototype hardware which may not match the configuration of a final product. Unfortunately, this also means that DEXT developers will always have at least two entitlement variants (the public development variant and the "private" approved entitlement), which is what then causes the problem I mentioned in #2. The Automatic Solution: If you're using Xcode 16 or above, then Xcode's Automatic code sign support will work all DEXT Families, with the exception of distribution signing the PCI and USB Families. For completeness, here is how that Automatic flow should work: Change the code signing configuration to "Automatic". Add the capability using Xcode. If you've been approved for one of these entitlements, the one oddity you'll see is that adding your approved capability will add both the approved AND the development variant, while deleting either will delete both. This is a visual side effect of #2 above; however, aside from the exception described below, it can be ignored. Similarly, you can sign distribution builds by creating a build archive and then exporting the build using the standard Xcode flow. __ Kevin Elliott DTS Engineer, CoreOS/Hardware
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281
Dec ’25
Basic introduction to DEXT Matching and Loading
Note: This document is specifically focused on what happens after a DEXT has passed its initial code-signing checks. Code-signing issues are dealt with in other posts. Preliminary Guidance: Using and understanding DriverKit basically requires understanding IOKit, something which isn't entirely clear in our documentation. The good news here is that IOKit actually does have fairly good "foundational" documentation in the documentation archive. Here are a few of the documents I'd take a look at: IOKit Fundamentals IOKit Device Driver Design Guidelines Accessing Hardware From Applications Special mention to QA1075: "Making sense of IOKit error codes",, which I happened to notice today and which documents the IOReturn error format (which is a bit weird on first review). Those documents do not cover the full DEXT loading process, but they are the foundation of how all of this actually works. Understanding the IOKitPersonalities Dictionary The first thing to understand here is that the "IOKitPersonalities" is called that because it is in fact a fully valid "IOKitPersonalities" dictionary. That is, what the system actually uses that dictionary "for" is: Perform a standard IOKit match and load cycle in the kernel. The final driver in the kernel then uses the DEXT-specific data to launch and run your DEXT process outside the kernel. So, working through the critical keys in that dictionary: "IOProviderClass"-> This is the in-kernel class that your in-kernel driver loads "on top" of. The IOKit documentation and naming convention uses the term "Nub", but the naming convention is not consistent enough that it applies to all cases. "IOClass"-> This is the in-kernel class that your driver loads on top of. This is where things can become a bit confused, as some families work by: Routing all activity through the provider reference so that the DEXT-specific class does not matter (PCIDriverKit). Having the DEXT subclass a specific subclass which corresponds to a specific kernel driver (SCSIPeripheralsDriverKit). This distinction is described in the documentation, but it's easy to overlook if you don't understand what's going on. However, compare PCIDriverKit: "When the system loads your custom PCI driver, it passes an IOPCIDevice object as the provider to your driver. Use that object to read and write the configuration and memory of your PCI hardware." Versus SCSIPeripheralsDriverKit: Develop your driver by subclassing IOUserSCSIPeripheralDeviceType00 or IOUserSCSIPeripheralDeviceType05, depending on whether your device works with SCSI Block Commands (SBC) or SCSI Multimedia Commands (SMC), respectively. In your subclass, override all methods the framework declares as pure virtual. The reason these differences exist actually comes from the relationship and interactions between the DEXT families. Case in point, PCIDriverKit doesn't require a specific subclass because it wants SCSIControllerDriverKit DEXTs to be able to directly load "above" it. Note that the common mistake many developers make is leaving "IOUserService" in place when they should have specified a family-specific subclass (case 2 above). This is an undocumented implementation detail, but if there is a mismatch between your DEXT driver ("IOUserSCSIPeripheralDeviceType00") and your kernel driver ("IOUserService"), you end up trying to call unimplemented kernel methods. When a method is "missing" like that, the codegen system ends up handling that by returning kIOReturnUnsupported. One special case here is the "IOUserResources" provider. This class is the DEXT equivalent of "IOResources" in the kernel. In both cases, these classes exist as an attachment point for objects which don't otherwise have a provider. It's specifically used by the sample "Communicating between a DriverKit extension and a client app" to allow that sample to load on all hardware but is not something the vast majority of DEXT will use. Following on from that point, most DEXT should NOT include "IOMatchCategory". Quoting IOKit fundamentals: "Important: Any driver that declares IOResources as the value of its IOProviderClass key must also include in its personality the IOMatchCategory key and a private match category value. This prevents the driver from matching exclusively on the IOResources nub and thereby preventing other drivers from matching on it. It also prevents the driver from having to compete with all other drivers that need to match on IOResources. The value of the IOMatchCategory property should be identical to the value of the driver's IOClass property, which is the driver’s class name in reverse-DNS notation with underbars instead of dots, such as com_MyCompany_driver_MyDriver." The critical point here is that including IOMatchCategory does this: "This prevents the driver from matching exclusively on the IOResources nub and thereby preventing other drivers from matching on it." The problem here is that this is actually the exceptional case. For a typical DEXT, including IOMatchCategory means that a system driver will load "beside" their DEXT, then open the provider blocking DEXT access and breaking the DEXT. DEXT Launching The key point here is that the entire process above is the standard IOKit loading process used by all KEXT. Once that process finishes, what actually happens next is the DEXT-specific part of this process: IOUserServerName-> This key is the bundle ID of your DEXT, which the system uses to find your DEXT target. IOUserClass-> This is the name of the class the system instantiates after launching your DEXT. Note that this directly mimics how IOKit loading works. Keep in mind that the second, DEXT-specific, half of this process is the first point your actual code becomes relevant. Any issue before that point will ONLY be visible through kernel logging or possibly the IORegistry. __ Kevin Elliott DTS Engineer, CoreOS/Hardware
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2d
Looking for USBSerialDriver sample code
I would like to write a driver that supports our custom USB-C connected device, which provides a serial port interface. USBSerialDriverKit looks like the solution I need. Unfortunately, without a decent sample, I'm not sure how to accomplish this. The DriverKit documentation does a good job of telling me what APIs exist but it is very light on semantic information and details about how to use all of these API elements. A function call with five unexplained parameters just is that useful to me. Does anyone have or know of a resource that can help me figure out how to get started?
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744
Feb ’25
Implementing a virtual serial port using DriverKit/SerialDriverKit
I'm trying to implement a virtual serial port driver for my ham radio projects which require emulating some serial port devices and I need to have a "backend" to translate the commands received by the virtual serial port into some network-based communications. I think the best way to do that is to subclass IOUserSerial? Based on the available docs on this class (https://developer.apple.com/documentation/serialdriverkit/iouserserial), I've done the basic implementation below. When the driver gets loaded, I can see sth like tty.serial-1000008DD in /dev and I can use picocom to do I/O on the virtual serial port. And I see TxDataAvailable() gets called every time I type a character in picocom. The problems are however, firstly, when TxDataAvailable() is called, the TX buffer is all-zero so although the driver knows there is some incoming data received from picocom, it cannot actually see the data in neither Tx/Rx buffers. Secondly, I couldn't figure out how to notify the system that there are data available for sending back to picocom. I call RxDataAvailable(), but nothing appears on picocom, and RxFreeSpaceAvailable() never gets called back. So I think I must be doing something wrong somewhere. Really appreciate it if anyone could point out how should I fix it, many thanks! VirtualSerialPortDriver.cpp: constexpr int bufferSize = 2048; using SerialPortInterface = driverkit::serial::SerialPortInterface; struct VirtualSerialPortDriver_IVars {     IOBufferMemoryDescriptor *ifmd, *rxq, *txq;     SerialPortInterface *interface;     uint64_t rx_buf, tx_buf;     bool dtr, rts; }; bool VirtualSerialPortDriver::init() {     bool result = false;     result = super::init();     if (result != true)     {         goto Exit;     }     ivars = IONewZero(VirtualSerialPortDriver_IVars, 1);     if (ivars == nullptr)     {         goto Exit;     }     kern_return_t ret;     ret = ivars->rxq->Create(kIOMemoryDirectionInOut, bufferSize, 0, &ivars->rxq);     if (ret != kIOReturnSuccess) {         goto Exit;     }     ret = ivars->txq->Create(kIOMemoryDirectionInOut, bufferSize, 0, &ivars->txq);     if (ret != kIOReturnSuccess) {         goto Exit;     }     IOAddressSegment ioaddrseg;     ivars->rxq->GetAddressRange(&ioaddrseg);     ivars->rx_buf = ioaddrseg.address;     ivars->txq->GetAddressRange(&ioaddrseg);     ivars->tx_buf = ioaddrseg.address;     return true; Exit:     return false; } kern_return_t IMPL(VirtualSerialPortDriver, HwActivate) {     kern_return_t ret;     ret = HwActivate(SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         goto Exit;     }     // Loopback, set CTS to RTS, set DSR and DCD to DTR     ret = SetModemStatus(ivars->rts, ivars->dtr, false, ivars->dtr);     if (ret != kIOReturnSuccess) {         goto Exit;     } Exit:     return ret; } kern_return_t IMPL(VirtualSerialPortDriver, HwDeactivate) {     kern_return_t ret;     ret = HwDeactivate(SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         goto Exit;     } Exit:     return ret; } kern_return_t IMPL(VirtualSerialPortDriver, Start) {     kern_return_t ret;   ret = Start(provider, SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         return ret;     }     IOMemoryDescriptor *rxq_, *txq_;     ret = ConnectQueues(&ivars->ifmd, &rxq_, &txq_, ivars->rxq, ivars->txq, 0, 0, 11, 11);     if (ret != kIOReturnSuccess) {         return ret;     }     IOAddressSegment ioaddrseg;     ivars->ifmd->GetAddressRange(&ioaddrseg);     ivars->interface = reinterpret_cast<SerialPortInterface*>(ioaddrseg.address);     SerialPortInterface &intf = *ivars->interface;     ret = RegisterService();     if (ret != kIOReturnSuccess) {         goto Exit;     }     TxFreeSpaceAvailable(); Exit:     return ret; } void IMPL(VirtualSerialPortDriver, TxDataAvailable) {     SerialPortInterface &intf = *ivars->interface;     // Loopback     // FIXME consider wrapped case     size_t tx_buf_sz = intf.txPI - intf.txCI;     void *src = reinterpret_cast<void *>(ivars->tx_buf + intf.txCI); //    char src[] = "Hello, World!";     void *dest = reinterpret_cast<void *>(ivars->rx_buf + intf.rxPI);     memcpy(dest, src, tx_buf_sz);     intf.rxPI += tx_buf_sz;     RxDataAvailable();     intf.txCI = intf.txPI;     TxFreeSpaceAvailable();     Log("[TX Buf]: %{public}s", reinterpret_cast<char *>(ivars->tx_buf));     Log("[RX Buf]: %{public}s", reinterpret_cast<char *>(ivars->rx_buf)); // dmesg confirms both buffers are all-zero     Log("[TX] txPI: %d, txCI: %d, rxPI: %d, rxCI: %d, txqoffset: %d, rxqoffset: %d, txlogsz: %d, rxlogsz: %d",         intf.txPI, intf.txCI, intf.rxPI, intf.rxCI, intf.txqoffset, intf.rxqoffset, intf.txqlogsz, intf.rxqlogsz); } void IMPL(VirtualSerialPortDriver, RxFreeSpaceAvailable) {     Log("RxFreeSpaceAvailable() called!"); } kern_return_t   IMPL(VirtualSerialPortDriver,HwResetFIFO){     Log("HwResetFIFO() called with tx: %d, rx: %d!", tx, rx);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwSendBreak){     Log("HwSendBreak() called!");     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramUART){     Log("HwProgramUART() called, BaudRate: %u, nD: %d, nS: %d, P: %d!", baudRate, nDataBits, nHalfStopBits, parity);     kern_return_t ret = kIOReturnSuccess;     return ret; }      kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramBaudRate){     Log("HwProgramBaudRate() called, BaudRate = %d!", baudRate);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramMCR){     Log("HwProgramMCR() called, DTR: %d, RTS: %d!", dtr, rts);     ivars->dtr = dtr;     ivars->rts = rts;     kern_return_t ret = kIOReturnSuccess; Exit:     return ret; } kern_return_t  IMPL(VirtualSerialPortDriver, HwGetModemStatus){     *cts = ivars->rts;     *dsr = ivars->dtr;     *ri = false;     *dcd = ivars->dtr;     Log("HwGetModemStatus() called, returning CTS=%d, DSR=%d, RI=%d, DCD=%d!", *cts, *dsr, *ri, *dcd);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramLatencyTimer){     Log("HwProgramLatencyTimer() called!");     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramFlowControl){     Log("HwProgramFlowControl() called! arg: %u, xon: %d, xoff: %d", arg, xon, xoff);     kern_return_t ret = kIOReturnSuccess; Exit:     return ret; }
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2.1k
Feb ’25
No logs from log stream | grep CompanyName
I have USB DriverKit driver. When I use the log command below to get log, there is logs from my driver on my own M-series MacBook where the driver is built using developer account. log stream | grep CompanyName But on other mac like (M-series) Mac Mini, there is no log captured from driver though the driver is communicating with the machine correctly. The only log captured are from MacOS regarding CompanyName driver status/unload/load. The MacOS is Sonoma 14.7.2 and 14.7.3. Please advise on how to get log from driver since writing to files is not allowed in DriverKit. I need logs to troubleshoot on Mac Mini. Thanks.
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517
Feb ’25
howto measure time_interval since physical plugin of a USB-gadget ?
=1) The situation: 1A) I make both a "DExt" and a "SDK" for still-imaging-USB-gadgets and MACOS>=14 ,iPADOS>=17 1B) One of the USB-gadgets needs warm_up after PlugIn (i.e End-User-App must know "now-TheMomentOfPlugIn" with precision ~1sec). =2) The question is how to do "1B" rationally? =3) My speculative guess: in BSD-descendant I expect existence (somewhere) of a "normal file" through "macports etc", which has normal "file creation time". Such a "file creation time" (accessible better via IORegistryEntry... at SDK-level; possibly via IOUSBHostInterface at DExt-level) is cognitive target of mine. =4) Additional constraints: Technically absent. I freely modify code either DExt (descendant of IOUSBHostInterface) or SDK-level (IORegistryEntryGetRegistryEntryID, IORegistryEntry...)
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633
Feb ’25
Fails to capture IOUSBHostInterface with macOS 15.3 despite root privileges in app
I have an app that captures USB storage device and sends some commands to it. The app has a privilege helper tool which captures the USB device. Everything was working fine upto macOS 15.2 but it 15.3 update broke the functionality. When the helper tool tries to capture the USB device, it is able to capture IOUSBHostDevice but fails to capture IOUSBHostInterface. The error is Code: 3758097097; Domain: IOUSBHostErrorDomain; Description: Failed to create IOUSBHostInterface.; Reason: Failed [super init] I have verified the UID, EUID, GID, EGID = 0 for the helper process. So by IOUSBHost documentation it should have worked. The code that cause the error inside the helper tool is func captureUSBInterface(interface: io_service_t) -> IOUSBHostInterface? { let queue = DispatchQueue(label: "com.example.usbdevice.queue2") var capturedInterface: IOUSBHostInterface? do { capturedInterface = try IOUSBHostInterface(__ioService: interface, options: .deviceCapture, queue: queue, interestHandler: nil) } catch { NSLog("Failed to capture USB interface: \(error)") return nil } return capturedInterface } The app has sandbox=False and is distributed outside of the App Store. Please advise (long-term, short-term solutions) on how to make this work.
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2
557
Feb ’25
Trouble using IOLog from a dext
Trying to use IOLog to print out a message from a dext. When I try to use IOLog, I get , though I did not or thought I did not tag it as private. I have tried to update the info.plist file for the dext according to https://developer.apple.com/forums/thread/705810, but that has not helped, or perhaps I am not defining it correctly since it's a dext. Anyone else had this issue, and how did you fix it?
5
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650
Feb ’25
NFC Communication Issues on iPhone 12–15 with NXP NTAG 5 (ISO15693 Pass-Through Mode)
We are developing an iOS app that communicates with a device using an NXP NTAG 5 chip in ISO15693 pass-through mode. While the app works flawlessly on older iPhone models (iPhone 8, SE, X) and most Android devices, we are experiencing severe reliability issues on iPhone 12, 13, 14, and 15. Issue Summary On newer iPhones (12–15), 90% of communication attempts fail. Retry strategies do not work, as the NFC session is unexpectedly canceled while handling CoreNFC custom commands. The issue is not consistent—sometimes all requests fail immediately, while other times, a batch of reads might succeed unexpectedly before failing again. Technical Details The failure occurs while executing the following request, which should return 256 bytes: tag.customCommand(requestFlags: .highDataRate, customCommandCode: commandCode, customRequestParameters: Data(byteArray)) { (responseData, error) in } The returned error is: -[NFCTagReaderSession transceive:tagUpdate:error:]:897 Error Domain=NFCError Code=100 "Tag connection lost" UserInfo={NSLocalizedDescription=Tag connection lost} For reference, we tested a comparable STM ST25 chip in ISO15693 and NDEF mode, and the exact same issue occurs. Observations and Debugging Attempts Positioning of the NFC antenna has been tested extensively. Disabling Bluetooth and Wi-Fi does not improve reliability. Rebooting the device or waiting between attempts sometimes improves success rates but does not provide a structural fix. When reading multiple blocks (e.g., 15 blocks of 256 bytes each): The process often fails within the first three blocks. After multiple failures, it may suddenly succeed in reading all blocks in one go before returning to a series of failures. The nfcd logs suggest issues at the low-level NFC and SPMI layers, indicating potential hardware or firmware-related problems: error 17:36:18.289099+0100 nfcd phOsalNfc_LogStr:65 NCI DATA RSP : Timer expired before data is received! error 17:36:18.292936+0100 nfcd NFHardwareSerialQuerySPMIError:1339 "Invalid argument" errno=22 setsockopt: SYSPROTO_CONTROL:IO_STOCKHOLM_SPMIERRORS error 17:36:18.293036+0100 nfcd phTmlNfc_SpmiDrvErrorStatus:1157 "Invalid argument" errno=22 Failed to query SPMI error registers error 17:36:18.293235+0100 nfcd phOsalNfc_LogStr:65 phLibNfc_SpmiStsRegInfoNtfHandler: Read Spmi Status Failed - pInfo set to NULL error 17:36:18.293313+0100 nfcd _Callback_NFDriverNotifyGeneral:2353 Unknown notification: 0x5b error 17:36:18.294163+0100 nfcd phOsalNfc_LogStr:65 Target Lost!! error 17:36:18.294678+0100 nfcd -[_NFReaderSession handleSecureElementTransactionData:appletIdentifier:]:164 Unimplemented error 17:36:18.294760+0100 nfcd -[_NFReaderSession handleSecureElementTransactionData:appletIdentifier:]:164 Unimplemented error 17:36:18.320132+0100 nfcd phOsalNfc_LogStr:65 ISO15693 XchgData,PH_NCINFC_STATUS_RF_FRAME_CORRUPTED Detected by NFCC during Data Exchange error 17:36:18.320291+0100 nfcd phOsalNfc_LogU32:74 phNciNfc_ChkDataRetransmission: Re-transmitting Data pkt Attempt..=1 error 17:36:18.622050+0100 nfcd phOsalNfc_LogStr:65 NCI DATA RSP : Timer expired before data is received! error 17:36:18.625857+0100 nfcd NFHardwareSerialQuerySPMIError:1339 "Invalid argument" errno=22 setsockopt: SYSPROTO_CONTROL:IO_STOCKHOLM_SPMIERRORS error 17:36:18.625919+0100 nfcd phTmlNfc_SpmiDrvErrorStatus:1157 "Invalid argument" errno=22 Failed to query SPMI error registers error 17:36:18.626132+0100 nfcd phOsalNfc_LogStr:65 phLibNfc_SpmiStsRegInfoNtfHandler: Read Spmi Status Failed - pInfo set to NULL error 17:36:18.626182+0100 nfcd _Callback_NFDriverNotifyGeneral:2353 Unknown notification: 0x5b error 17:36:18.626899+0100 nfcd phOsalNfc_LogStr:65 Target Lost!! error 17:36:18.627482+0100 nfcd -[_NFReaderSession handleSecureElementTransactionData:appletIdentifier:]:164 Unimplemented error 17:36:18.627568+0100 nfcd -[_NFReaderSession handleSecureElementTransactionData:appletIdentifier:]:164 Unimplemented error 17:36:18.833174+0100 nfcd -[_NFReaderSession handleSecureElementTransactionData:appletIdentifier:]:164 Unimplemented error 17:36:19.145289+0100 nfcd phOsalNfc_LogStr:65 NCI DATA RSP : Timer expired before data is received! error 17:36:19.149233+0100 nfcd NFHardwareSerialQuerySPMIError:1339 "Invalid argument" errno=22 setsockopt: SYSPROTO_CONTROL:IO_STOCKHOLM_SPMIERRORS error 17:36:19.149353+0100 nfcd phTmlNfc_SpmiDrvErrorStatus:1157 "Invalid argument" errno=22 Failed to query SPMI error registers error 17:36:19.149730+0100 nfcd phOsalNfc_LogStr:65 phLibNfc_SpmiStsRegInfoNtfHandler: Read Spmi Status Failed - pInfo set to NULL error 17:36:19.149797+0100 nfcd _Callback_NFDriverNotifyGeneral:2353 Unknown notification: 0x5b error 17:36:19.150463+0100 nfcd phOsalNfc_LogStr:65 Target Lost!! Any solutions? Has anyone else encountered similar behavior with CoreNFC on iPhone 12–15? Could this be related to changes in NFC hardware or power management in newer iPhone models? Any suggestions on possible workarounds or alternative approaches would be greatly appreciated.
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531
Feb ’25
The Map() of IOBufferMemoryDescriptor failure and cause the DriverKit Start() repeat
Hello Everyone, I am trying to develop a DriverKit for RAID system, using PCIDriverKit & SCSIControllerDriverKit framework. The driver can detect the Vendor ID and Device ID. But before communicating to the RAID system, I would like to simulate a virtual Volume using a memory block to talk with macOS. In the UserInitializeController(), I allocated a 512K memory for a IOBufferMemoryDescriptor* volumeBuffer, but fail to use Map() to map memory for volumeBuffer. result = ivars->volumeBuffer->Map( 0, // Options: Use default 0, // Offset: Start of the buffer ivars->volumeSize, // Length: Must not exceed buffer size 0, // Flags: Use default nullptr, // Address space: Default address space &mappedAddress // Output parameter ); Log("Memory mapped completed at address: 0x%llx", mappedAddress); // this line never run The Log for Map completed never run, just restart to run the Start() and makes this Driver re-run again and again, in the end, the driver eat out macOS's memory and system halt. Are the parameters for Map() error? or I should not put this code in UserInitializeController()? Any help is appreciated! Thanks in advance. Charles
0
0
389
Mar ’25
Inconsistent KEXT Status Between System Information and kextstat
Hello Everyone, I have noticed an inconsistency in the KEXT status between the System Information Extensions section and the output of the kextstat command. In System Information, the extension appears as loaded: ACS6x: Version: 3.8.3 Last Modified: 2025/3/10, 8:03 PM Bundle ID: com.Accusys.driver.Acxxx Loaded: Yes Get Info String: ACS6x 3.8.4 Copyright (c) 2004-2020 Accusys, Ltd. Architectures: arm64e 64-Bit (Intel): No Location: /Library/Extensions/ACS6x.kext/ Kext Version: 3.8.3 Load Address: 0 Loadable: Yes Dependencies: Satisfied Signed by: Developer ID Application: Accusys, Inc (K3TDMD9Y6B) Issuer: Developer ID Certification Authority Signing time: 2025-03-10 12:03:20 +0000 Identifier: com.Accusys.driver.Acxxx TeamID: K3TDMD9Y6B However, when I check using kextstat, it does not appear as loaded: $ kextstat | grep ACS6x Executing: /usr/bin/kmutil showloaded No variant specified, falling back to release I use a script to do these jobs echo " Change to build/Release" echo " CodeSign ACS6x.kext" echo " Compress to zip file" echo " Notary & Staple" echo " Unload the old Acxxx Driver" echo " Copy ACS6x.kext driver to /Library/Extensions/" echo " Change ACS6x.kext driver owner" echo " Loaded ACS6x.kext driver" sudo kextload ACS6x.kext echo " Rebiuld system cache" sudo kextcache -system-prelinked-kernel sudo kextcache -system-caches sudo kextcache -i / echo " Reboot" sudo reboot But it seems that the KEXT is not always loaded successfully. What did I forget to do? Any help would be greatly appreciated. Best regards, Charles
2
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303
Mar ’25
CoreAudio server plugin: propagate kAudioObjectPropertyName change
When my virtual CoreAudio server plugins propagates a change to it´s device name the CoreAudio system does not seem to reflect the change. My user mode application subscribes to the property change and receives the change though. I also alternatively submitted a kAudioObjectPropertyName change with the same effect. Is this possible at all and what needs to be done then? Are there restrictions about which properties can be successfully changed and are reflected by the system? Any hint is highly appreciated! Thanks
1
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78
Mar ’25
Assistance Needed for Migrating KEXT Delay Code to DriverKit
Hello Everyone, I am working on migrating a KEXT to DriverKit but am struggling to resolve a specific issue. The code in question is simple, but I haven't been able to find a solution. void AME_IO_milliseconds_Delay(AME_U32 Delay) { Log("AME_IO_milliseconds_Delay()"); IOSleep(Delay); return; } //delay for a number of microseconds void AME_IO_microseconds_Delay(AME_U32 Delay) { Log("AME_IO_microseconds_Delay()"); IODelay(Delay); return; } I've sought help from Copilot and ChatGPT, but their suggestions haven't worked. Any guidance on how to implement this functionality in DriverKit would be greatly appreciated. Thank you for your time and assistance. Best regards, Charles
1
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263
Mar ’25
Why UserInitializeTargetForID() not be invoked after UserCreateTargetForID() successfully?
Hello Everyone, I am trying to create a Fake SCSI target based on SCSIControllerDriverKit.framework and inherent from IOUserSCSIParallelInterfaceController, here is the code kern_return_t IMPL(DRV_MAIN_CLASS_NAME, Start) { ... // Programmatically create a null SCSI Target SCSIDeviceIdentifier nullTargetID = 0; // Example target ID, adjust as needed ret = UserCreateTargetForID(nullTargetID, nullptr); if (ret != kIOReturnSuccess) { Log("Failed to create Null SCSI Target for ID %llu", nullTargetID); return ret; } ... } According the document UserCreateTargetForID, after creating a TargetID successfully, the framework will call the UserInitializeTargetForID() The document said: As part of the UserCreateTargetForID call, the kernel calls several APIs like UserInitializeTargetForID which run on the default dispatch queue of the dext. But after UserCreateTargetForID created, why the UserInitializeTargetForID() not be invoked automatically? Here is the part of log show init() - Start init() - End Start() - Start Start() - try 1 times UserCreateTargetForID() - Start Allocating resources for Target ID 0 UserCreateTargetForID() - End Start() - Finished. UserInitializeController() - Start - PCI vendorID: 0x14d6, deviceID: 0x626f. - BAR0: 0x1, BAR1: 0x200004. - GetBARInfo() - BAR1 - MemoryIndex: 0, Size: 262144, Type: 0. UserInitializeController() - End UserStartController() - Start - msiInterruptIndex : 0x00000000 - interruptType info is 0x00010000 - PCI Dext interrupt final value, return status info is 0x00000000 UserStartController() - End Any assistance would be greatly appreciated! Thank you in advance for your support. Best regards, Charles
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404
Mar ’25
DriverKit IOUSBHostInterface iterator always empty
I'm trying to iterate through a USB device but the iterator is always empty or contains only the matched interface: Single interface in Iterator This happens when my driver matches against the interface. Because I need to use 2 interfaces (control and cdc), I try to open the IOUSBHostDevice (copied from the interface) and iterate through the rest, but I only get the interface my dext matched with. Empty Iterator I decided to match against USB communication devices, thinking things would be different. However, this time the interface iterator is completely empty (provider is IOUSBHostDevice). Here's a snippet of my code before iterating with IOUSBHostDevice->CopyInterface(): // teardown the configured interfaces. result = device->SetConfiguration(ivars->Config, true); __Require_noErr_Action(result, _failure_Out, ELOG("IOUSBHostDevice::SetConfiguration failed 0x%x", result)); // open usb device result = device->Open(this, 0, 0); __Require_noErr_Action(result, _failure_Out, ELOG("Failed to open IOUSBHostDevice")); // Get interface iterator result = device->CreateInterfaceIterator(&iterRef); __Require_noErr_Action(result, _failure_Out, ELOG("IOUSBHostDevice::CreateInterfaceIterator failed failed: 0x%x", result));
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286
Mar ’25
FTDI Serial Support on iOS18 with USB-C iPhones
I read that iPadOS supports driverkit, and, presumably, the same serial FTDI UARTs as macOS. Has this been migrated to USB-C iPhones on iOS 18? After some searching, the developer doc is not clear, and web responses are contradictory. We are currently using it for a wired sensor option of our BlueTooth HR sensor. When it is used in wired config, the radios are turned off. This is important to some of our customers. Since Lightning MFI sensors are being discontinued with Apple killing Lightning, we would love to have an alternative for iOS. -- Harald
2
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671
Mar ’25
Dext not initializing with a log "Failed to write extension load report plist"
When plugging in my matched USB device I see the logs below. It seems the kernelmanagerd process is sandboxed and can't write out the reason my Dext failed to load. Is there somewhere else I can look for this info? default 11:03:22.175152-0700 kernelmanagerd Received kext load notification: me.keithg.MyUserUSBInterfaceDriver default 11:03:22.177637-0700 kernel 1 duplicate report for Sandbox: icdd(2124) allow file-read-data /Library/Image Capture/Devices error 11:03:22.177681-0700 kernel Sandbox: kernelmanagerd(545) deny(1) file-write-create /private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/com.apple.kernelmanagerd/TemporaryItems com.apple.libcoreservices error 11:03:22.177711-0700 kernelmanagerd mkdir: path=/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/com.apple.kernelmanagerd/TemporaryItems/ mode= -rwx------: [1: Operation not permitted] error 11:03:22.179361-0700 kernel Sandbox: kernelmanagerd(545) deny(1) file-write-create /private/var/db/loadedkextmt.plist.sb-5a00fc77-LNttZF com.apple.libcoreservices error 11:03:22.177755-0700 kernelmanagerd _dirhelper_relative_internal: error for path <private>: [1: Operation not permitted] com.apple.accessories default 11:03:22.177674-0700 WindowServer Sending analytics event... (eventName: com.apple.ioport.transport.USB.published) error 11:03:22.179913-0700 kernelmanagerd Failed to write extension load report plist.
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155
Mar ’25
iOS support for SCSI and NVME commands.
We have a macOS application which interacts with our USB and PCI devices to perform SCSI and NVME commands on them. We use IOUSBHost, IOUSBLib and IOKitLib for USB interface and have created a custom driver to interact with PCI devices. Is there a way we can implement a similar functionality for iOS as well if we connect the cards and readers using OTG?
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163
Mar ’25
Issue Writing to BAR1 After BAR0 is Unavailable
Hello Everyone, I encountered an issue with PCI memory access in DriverKit. In my case, BAR0 is not available, but BAR1 is ready for use. Here’s the log output: !!! ERROR : Failed to get BAR0 info (error: 0xe00002f0). !!! BAR1 - MemoryIndex: 0x00000000, Size: 0x00040000, Type: 0 Issue Description When I initially wrote to BAR0 using memoryIndex = 0, it worked successfully: AME_Address_Write_32(pAMEData, pAMEData->memoryIndex, AME_HOST_INT_MASK_REGISTER, 0x0F); However, I mistakenly forgot to update memoryIndex to 1 for BAR1. Surprisingly, the write operation still succeeded. When I fixed memoryIndex = 1 for BAR1, the write operation no longer had any effect. There was no error, but the expected behavior did not occur. Relevant API (From IOPCIDevice.iig) /*! /*! * @brief Writes a 32-bit value to the PCI device's aperture at a given memory index. * @discussion This method writes a 32-bit register on the device and returns its value. * @param memoryIndex An index into the array of ranges assigned to the device. * @param offset An offset into the device's memory specified by the index. * @param data A 32-bit value to be written in host byte order. */ void MemoryWrite32(uint8_t memoryIndex, uint64_t offset, uint32_t data) LOCALONLY; Log Output: Writes to BAR0 (memoryIndex = 0) AME_Address_Write_32() called memoryIndex: 0, offset: 0x34, data: 0xf Wrote data 0xF to offset 52 AME_Address_Write_32() called memoryIndex: 0, offset: 0xa0, data: 0x1 Wrote data 0x1 to offset 160 AME_Address_Write_32() called memoryIndex: 0, offset: 0x20, data: 0xffffffff Wrote data 0xFFFFFFFF to offset 32 Writes to BAR1 (memoryIndex = 1) – No Response AME_Address_Write_32() called memoryIndex: 1, offset: 0x34, data: 0xf No confirmation log, no visible effect. Questions What should memoryIndex be set to for BAR1? The log shows "BAR1 - MemoryIndex: 0x00000000", but should I be using 1 instead? How can I verify if a write operation to BAR1 is successful? Is there a way to check if the memory region is actually writable? Should I use MemoryRead32() to confirm the written value? Any guidance would be greatly appreciated! Best Regards, Charles
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133
Mar ’25