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DriverKit IOUserSCSIPeripheralDeviceType00: kernel panic when setPowerState exceeds 20 seconds
We have an IOUserSCSIPeripheralDeviceType00 class DEXT supporting USB attached devices. With some high-capacity drives, the default setPowerState can exceed 20s to complete. This triggers a kernel panic, although this drive behavior is not unexpected. With a kernel extension implementing similar functionality we see no such problem as it appears from reading of Apple open source the timeout was 100s. What changes will allow setPowerState to complete without the kernel panic? kernel panic report excerpt attached. panic-full-2025-09-04-063127.0003.txt
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Oct ’25
DriverKit DEXT Logs Only Once, Subsequent Logs Are Lost Despite Normal Functionality
Hello everyone, I've encountered a very strange and persistent logging issue with my DriverKit DEXT and would appreciate any insights from the community. [Problem Summary] My DriverKit DEXT, along with its companion Swift app, is functionally working perfectly. I can repeatedly call methods in the DEXT from the app (e.g., a Ping-Pong test and a StaticProcessInbandTask call) and receive the correct response every time. However, the os_log messages within my IOUserClient subclass are only successfully recorded for the very first set of interactions. After that, all subsequent logs are completely missing. What's even stranger is that all successfully recorded logs are attributed to the kernel: process, even for purely user-space methods like ExternalMethod. [Development Environment] macOS: 15.7.1 Xcode: 16.4 Hardware: MacBook Pro M1 DEXT Logging Macro (Log.h): #include <os/log.h> #define Log(fmt, ...) \ do { \ os_log(OS_LOG_DEFAULT, "[%{public}s] " fmt, __FUNCTION__, ##__VA_ARGS__); \ } while (0) [Steps to Reproduce & Observed Behavior] The DEXT is successfully loaded via the companion app. I click the "Ping-Pong" button, then the "Process InBand" button in the app. The app's UI log correctly shows that the request was sent and a successful response was received from the DEXT. I repeat step 2 multiple times. Each interaction works flawlessly from the app's perspective. I then use the log show command to export the logs from this period, for example: log show --last 5m | grep "com.accusys.Acxxx.driver" > dext_logs.txt Observed Result (Log Content): In the dext_logs.txt file, I can only see the logs from the very first Ping-Pong and the very first Process InBand call. All subsequent, successful operations leave no trace in the logs. kernel: (com.accusys.Acxxx.driver.dext) [ExternalMethod] // { --- kernel: (com.accusys.Acxxx.driver.dext) [ExternalMethod] // --- } kernel: (com.accusys.Acxxx.driver.dext) [StaticPingPong] // { --- kernel: (com.accusys.Acxxx.driver.dext) [StaticPingPong] // --- } kernel: (com.accusys.Acxxx.driver.dext) [ExternalMethod] // { --- kernel: (com.accusys.Acxxx.driver.dext) [ExternalMethod] // --- } kernel: (com.accusys.Acxxx.driver.dext) [StaticProcessInbandTask] // { --- kernel: (com.accusys.Acxxx.driver.dext) [StaticProcessInbandTask] // --- } <--- END OF FILE (No new logs appear after this point) ---> [Core Questions] Why are logs in IOUserClient subclass only recorded once? Given the DEXT is clearly still running and processing requests, why would os_log calls only succeed in writing to the system log database on the first interaction? Why are all logs attributed to the kernel? Why would logs from 100% user-space code like ExternalMethod and StaticPingPong be attributed to the kernel process? [Solutions Attempted That Did Not Work] I have verified with ps aux that the DEXT process (com.accusys.Acxxx.driver) is running continuously in the background and has not crashed. Attempted to force-restart the logging service with sudo killall logd, but the issue persists. Performed the most thorough reset possible using systemextensionsctl reset followed by a full reboot, then reinstalled the DEXT. The issue remains exactly the same. Thank you for any possible help or suggestions Best, Charles
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Oct ’25
How to completely uninstall the old kext driver?
Hi, On macOS 11 and earlier versions, we provided users with the following script to uninstall our kext driver: sudo pkgutil --only-files --files com.magewell.ProCapture | tr '\n' '\0' | xargs -n 1 -0 sudo rm -vf sudo pkgutil --only-dirs --files com.magewell.ProCapture | grep ProCapture[^/]*$ | tr '\n' '\0' | xargs -n 1 -0 sudo rm -rvf sudo pkgutil --forget com.magewell.ProCapture sudo kextcache -system-caches However, this script no longer works on macOS 13 and returns the following error: It looks like you're trying to update the system caches. As of macOS 11, the personality cache is no longer in use for keeping kext matching information up-to-date. For more information, see `man kmutil`. This indicates we can no longer use kextcache -system-caches to clear our driver cache. This creates an issue where even after installing the new dext driver, the dext driver cannot run due to the presence of the old kext driver. We've tried various methods but haven't been able to completely uninstall the old kext driver - after every new system update, the old kext reappears. The specific process is as follows: This is the sequence I followed in my latest test - Device is running macOS 13 Ventura w/ 4247 Pro Capture kext driver installed kmutil inspect | grep -i magewell - this returns references to the kext files in /Library/Extensions, which is expected because I have not yet removed the 4247 kext driver - then I ran the following combination of your removal script and my removal steps: cd / sudo rm -r /Library/Extensions/ProCaptureDriver.kext sudo rm -r /Library/Extensions/ProCaptureEvent.kext sudo rm /System/Volumes/Preboot/*/boot/*/System/Library/Caches/com.apple.kernelcaches/kernelcache.auxkc* sudo pkgutil --only-files --files com.magewell.ProCapture | tr '\n' '\0' | xargs -n 1 -0 sudo rm -vf sudo pkgutil --only-dirs --files com.magewell.ProCapture | grep ProCapture[^/]*$ | tr '\n' '\0' | xargs -n 1 -0 sudo rm -rvf sudo pkgutil --forget com.magewell.ProCapture sudo kextcache --clear-staging sudo kcditto sudo kmutil install --update-preboot sudo shutdown -r now - After this I ran 'kmutil inspect | grep -i magewell' and got no results, which seems good but... - then I ran the upgrade to macOS 15.7 Sequoia - Afterwards I ran 'kmutil inspect | grep -i magewell' and it returned references to the old /Library/Extensions kexts again, although the files no longer exist in /Library/Extensions - I then ran my cleanup process again (slightly different for Sequoia-available commands): sudo rm /System/Volumes/Preboot/*/boot/*/System/Library/Caches/com.apple.kernelcaches/kernelcache.auxkc* sudo kextcache --clear-staging sudo kmutil rebuild sudo kcditto sudo kmutil install --update-preboot sudo shutdown -r now - Then I ran 'kmutil inspect | grep -i magewell' and got no results again - As a next test I ran a minor update to macOS 15.7.1, then ran 'kmutil inspect | grep -i magewell' and the references to the old kexts came back again We have indeed identified a solution to address this issue: kmutil trigger-panic-medic --volume-root /Volumes/<YourVolumeName> However, this method requires booting into Recovery Mode, which is unacceptable for many of our customers. Especially for those who need bulk remote management, having personnel physically operate each machine one by one is simply not feasible. Therefore, is there a method to completely uninstall the kext driver while in normal mode? Thank you!
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Oct ’25
[DriverKit SCSI] SCSI probe stalls for Target ID > 0 with IOUserSCSIParallelInterfaceController
Hello everyone, We are migrating a KEXT storage driver to DriverKit. In our KEXT, we use a "one LUN = one Target" model and successfully create multiple targets in a loop during initialization. We are now trying to replicate this architecture in our DEXT. The issue is that only Target 0 is fully probed and mounted. For Target 1, the lifecycle silently stops after the first TEST UNIT READY command is successfully acknowledged. The macOS SCSI layer never sends any subsequent probe commands (like INQUIRY) to this target. The failure sequence for Target 1, observed from our logs (regardless of whether Target 0 is created), is as follows: AsyncCreateTargetForID(1) -> UserInitializeTargetForID(1) (Succeeds) UserProcessParallelTask(Target: 1, Opcode: TUR) (Succeeds) The DEXT correctly acknowledges the TUR command for Target 1 by returning kSCSITaskStatus_CHECK_CONDITION with UNIT ATTENTION in the Sense Data (Succeeds) <-- Breakpoint --> UserProcessParallelTask(Target: 1, Opcode: INQUIRY) (Never happens) Through log comparison, we have confirmed that the DEXT's response to the TUR command for Target 1 is identical to the successful KEXT's response. We have tried creating only Target 1 (skipping Target 0 entirely), but the behavior is exactly the same -> the probe still stalls after the TUR. We initially suspected a race condition caused by consecutive calls to AsyncCreateTargetForID(). We attempted several methods to ensure that targets are created sequentially, such as trying to build a "creation chain" using OSAction completion handlers. However, these attempts were unsuccessful due to various compilation errors and API misunderstandings. In any case, this "race condition" theory was ultimately disproven by our experiment where creating only Target 1 still resulted in failure. We would like to ask two questions: Is our inability to have a Target ID greater than 0 fully probed by macOS a bug in our own code, or could there be another reason we are unaware of? If we do indeed need a "one-after-another" creation mechanism for AsyncCreateTargetForID, what is the correct way to implement a "chained creation" using OSAction completion handlers in DriverKit? Thank you for any help or guidance. Best Regards, Charles
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Jan ’26
UserSendCDB fails due to permissions
I created a custom class that inherits from IOUserSCSIPeripheralDeviceType00 in the DriverKit SCSIPeripheralsDriverKit framework. When I attempted to send a vendor-specific command to a USB storage device using the UserSendCDB function of this class instance, the function returned the error: kIOReturnNotPrivileged (iokit_common_err(0x2c1)) // privilege violation However, when using UserSendCDB in the same way to issue standard SCSI commands such as INQUIRY or Test Unit Ready, no error occurred and the returned sense data was valid. Why is UserSendCDB able to send standard SCSI commands successfully, but vendor-specific commands return kIOReturnNotPrivileged? Is there any required entitlement, DriverKit capability, or implementation detail needed to allow vendor-specific CDBs? Below are the entitlements of my DriverKit extension: <dict> <key>com.apple.developer.driverkit.transport.usb</key> <array> <dict> <key>idVendor</key> <integer>[number of vendorid]</integer> </dict> </array> <key>com.apple.developer.driverkit</key> <true/> <key>com.apple.developer.driverkit.allow-any-userclient-access</key> <true/> <key>com.apple.developer.driverkit.allow-third-party-userclients</key> <true/> <key>com.apple.developer.driverkit.communicates-with-drivers</key> <true/> <key>com.apple.developer.driverkit.family.scsicontroller</key> <true/> </dict> If there is any additional configuration or requirement to enable vendor-specific SCSI commands, I would appreciate your guidance. Environment: macOS15.6 M2 MacBook Pro
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Jan ’26
RFID read
Hi! Following this ticket: https://developer.apple.com/forums/thread/808764?page=1#868010022 Is there any way to use the hardware RFID reading capabilities of an iPhone to read ISO15693 RF tags silently, and without a UI pop-up? Perhaps using other native iOS libraries than the NFC library? If not, is there a way for a business to request this feature be allowed in internally used apps only?
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400
Jan ’26
OSSystemExtensionsWorkspace on iPadOS
Hello! I have app (macos and iPadOS platforms) with empbedded DEXT. The DEXT executable runs fine on both platforms (ver 26.2). Trying to execute from iPad App code: let sysExtWs = OSSystemExtensionsWorkspace.shared let sysExts = try sysExtWs.systemExtensions(forApplicationWithBundleID: appBudleId) but always getting OSSystemExtensionError.Code.missingEntitlement error. Which entitlement am I missing? Thank You!
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How to prevent the popup "The disk you attached was not readable by the computer" from appearing?
Hello! We develop a SAS driver and a service application for DAS devices. When users in our application create a RAID array on the device: On the 1st step, our dext driver mounts a new volume. At this step DiskUtil automatically tries to mount it. As there is no file system on the new volume - the MacOS system popup appears "The disk you attached was not readable by the computer" On the 2nd step our application creates the file system on this new volume. So we do not need this MacOS system popup to appear (as it may frustrate our users). We found a way to disable the global auto mount but this solution also impacts on other devices (which is not good). Are there any other possibilities to prevent the popup "The disk you attached was not readable by the computer" from appearing?
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288
Jan ’26
iOS printing – Finishing (Punch) options not applied for images unless a preset is selected
When printing image/photo files via AirPrint, selected finishing options (e.g., Punch) are not applied unless a preset is chosen. reproduction steps: Select an image on iOS Tap Print → choose printer/server Set Finishing Options → Punch Print Observed: Finishing options not applied IPP trace shows no finisher attributes in the request working scenario: Select any Preset (e.g., Color) before printing Finishing options are then included in IPP and applied Note: Issue does not occur when printing PDFs from iOS; finisher attributes are sent correctly. Is this expected AirPrint behavior for image jobs, or could this be a bug in how iOS constructs the IPP request for photos?
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Kernel Panic: Power state transition (0 -> 2) timeout during DriverKit (DEXT) load sequence (IOUserSCSIParallelInterfaceController)
Hi Everyone, We are currently migrating a mature legacy KEXT to DriverKit for our PCIe SCSI storage controller (connected via Thunderbolt 3). During the DEXT load sequence, we have observed that the system automatically triggers a power state transition from State 0 (Off) to State 2 (On). However, this process results in a Kernel Panic due to a timeout after approximately 21 seconds. We have verified that our implementation of Start_Impl, UserInitializeController_Impl, and SetPowerState_Impl executes extremely fast, with a total execution time of less than one second. Specifically, SetPowerState_Impl returns kIOReturnSuccess immediately upon being called. Furthermore, our current Info.plist does not contain any IOPowerManagement dictionary or related keys. Despite the fast execution and the absence of explicit power management declarations in the plist, the kernel power management state machine (IOServicePM) still generates a 21-second timeout, leading to the following panic: Panic Log: panic(cpu 7 caller 0xfffffe0020be8fec): MySCSIDriver::setPowerState(0xfffffe2fb1a65c00 : 0xfffffe0020bfed88, 0 -> 2) timed out after 21257 ms @IOServicePM.cpp:5609 com.example.driver.dext: ( id: com.example.driver.dext; path: /Library/SystemExtensions/[UUID]/com.example.driver.dext; state: loaded ) Note on Previous Discussion: I would like to express my gratitude to Kevin from Apple DTS for the helpful discussion regarding the implementation of BundleParallelTask on the forums. Since then, we have shifted our development focus toward completing the overall management ecosystem, delivering a comprehensive operational interface for users, and handling specific user environments and behaviors. Our current priority is ensuring system stability—specifically resolving these Thunderbolt-related power management issues (sleep/wake)—to prepare the product for upcoming testing. I remain very grateful for the guidance provided on batch task optimization and intend to resume those optimizations once this critical stability baseline is secured. Technical Guidance Needed for PM Migration In our legacy KEXT, we utilized PMinit(), registerPowerDriver(), and joinPMtree() to precisely control the timing of power management registration. In transitioning to the DriverKit SDK, we have not found clear guidance on several key points: Standardized Migration Path: What is the recommended way to implement equivalent power management initialization (formerly PMinit) within a DriverKit subclass? In DriverKit, how should we replicate the behavior of manually calling registerPowerDriver and joinPMtree to ensure the driver is only monitored once the hardware is ready? Implicit Power Registration: Why does the system enforce a setPowerState(0 -> 2) transition on a subclass of IOUserSCSIParallelInterfaceController even when no IOPowerManagement dictionary is defined in the Info.plist? Is this a default behavior of the SCSI or PCI transport framework? Thunderbolt Specifics: Are there specific power proxying requirements or configurations for PCIe devices over Thunderbolt to avoid conflicts with the default IOPCIFamily power policies? Best Regards, Charles
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Why don't my os_log entries show up until the second time my driver loads?
I'm in the process of writing a DriverKit USBHostInterface driver, and while I'm finally starting to get there, I've run into a bit of a frustration with logging. Naturally I have a liberal amount of os_log calls that I'm using to troubleshoot my driver. However I've noticed that they don't show up until after the first time my driver has loaded. Meaning, for example, suppose I make a new build of my driver and it's bundled user-mode app, install the bundle to /Applications, run the installer, verify it took with systemextensionsctl list, fire up Console and start streaming log entries, then plug in my device. I can see the log entries that show that my driver is loaded, etc., then a bunch of kernel -> log entries, but none of my Start method log entries. If I unplug my device and plug it in again, my log entries show up as expected. Why is this and, more importantly, how can I fix it? I'd like to see those log entries the first time the driver loads, if I could.
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Supported way to expose an iPhone+controller as a macOS gamepad without restricted entitlements?
I’m prototyping a personal-use system that lets an iPhone with a physically attached controller act as an input device for a Mac. End goal: Use the iPhone as the transport and sensor host Use the attached physical controller for buttons/sticks Map the iPhone gyroscope to the controller’s right stick to get gyro aim in Mac games / cloud-streamed games such as GeForce NOW that don't support the gyro. What I’m trying to understand is whether Apple supports any path for this on macOS that does NOT require restricted entitlements or paid-program-only capabilities. What I’ve already found: CoreHID virtual HID device creation appears to require com.apple.developer.hid.virtual.device HIDDriverKit / system extensions appear to require Apple-granted entitlements as well GCVirtualController does not seem to solve the problem because I need a controller-visible device that other apps can see, not just controls inside my own app So my concrete question is: Is there any supported, entitlement-free way for a personal macOS app to expose a game-controller-like input device that other apps can consume system-wide? If not, is the official answer that this class of solution necessarily requires one of: CoreHID with restricted entitlement HIDDriverKit/system extension entitlement some other Apple-approved framework or program I’m missing I’m not asking about App Store distribution. This is primarily for local/personal use during development. I’m trying to understand the supported platform boundary before investing further. Any guidance on the recommended architecture for this use case would be appreciated.
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Neither macOS 14.7 "Standard" 'AppleUserHIDEventDriver' Matching Driver Nor Custom HIDDriverKit Driver 'IOUserHIDEventService::dispatchDigitizerTouchEvent' API Work for a HID-standard Digitizer Touch Pad Device
I have been working on a multi-platform multi-touch HID-standard digitizer clickpad device. The device uses Bluetooth Low Energy (BLE) as its connectivity transport and advertises HID over GATT. To date, I have the device working successfully on Windows 11 as a multi-touch, gesture-capable click pad with no custom driver or app on Windows. However, I have been having difficulty getting macOS to recognize and react to it as a HID-standard multi-touch click pad digitizer with either the standard Apple HID driver (AppleUserHIDEventDriver) or with a custom-coded driver extension (DEXT) modeled, based on the DTS stylus example and looking at the IOHIDFamily open source driver(s). The trackpad works with full-gesture support on Windows 11 and the descriptors seem to be compliant with the R23 Accessory Guidelines document, §15. With the standard, matching Apple AppleUserHIDEventDriver HID driver, when enumerating using stock-standard HID mouse descriptors, the device works fine on macOS 14.7 "Sonoma" as a relative pointer device with scroll wheel capability (two finger swipe generates a HID scroll report) and a single button. With the standard, matching Apple AppleUserHIDEventDriver HID driver, when enumerating using stock-standard HID digitizer click/touch pad descriptors (those same descriptors used successfully on Windows 11), the device does nothing. No button, no cursor, no gestures, nothing. Looking at ioreg -filtb, all of the key/value pairs for the driver match look correct. Because, even with the Apple open source IOHIDFamily drivers noted above, we could get little visibility into what might be going wrong, I wrote a custom DriverKit/HIDDriverKit driver extension (DEXT) (as noted above, based on the DTS HID stylus example and the open source IOHIDEventDriver. With that custom driver, I can get a single button click from the click pad to work by dispatching button events to dispatchRelativePointerEvent; however, when parsing, processing, and dispatching HID digitizer touch finger (that is, transducer) events via IOUserHIDEventService::dispatchDigitizerTouchEvent, nothing happens. If I log with: % sudo log stream --info --debug --predicate '(subsystem == "com.apple.iohid")' either using the standard AppleUserHIDEventDriver driver or our custom driver, we can see that our input events are tickling the IOHIDNXEventTranslatorSessionFilter HID event filter, so we know HID events are getting from the device into the macOS HID stack. This was further confirmed with the DTS Bluetooth PacketLogger app. Based on these events flowing in and hitting IOHIDNXEventTranslatorSessionFilter, using the standard AppleUserHIDEventDriver driver or our custom driver, clicks or click pad activity will either wake the display or system from sleep and activity will keep the display or system from going to sleep. In short, whether with the stock driver or our custom driver, HID input reports come in over Bluetooth and get processed successfully; however, nothing happens—no pointer movement or gesture recognition. STEPS TO REPRODUCE For the standard AppleUserHIDEventDriver: Pair the device with macOS 14.7 "Sonoma" using the Bluetooth menu. Confirm that it is paired / bonded / connected in the Bluetooth menu. Attempt to click or move one or more fingers on the touchpad surface. Nothing happens. For the our custom driver: Pair the device with macOS 14.7 "Sonoma" using the Bluetooth menu. Confirm that it is paired / bonded / connected in the Bluetooth menu. Attempt to click or move one or more fingers on the touchpad surface. Clicks are correctly registered. With transducer movement, regardless of the number of fingers, nothing happens.
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Dec ’25
iOS 26 iPhone won't charge and keeps restarting.
I have an iPhone 14 Pro. I downloaded the iOS 26 beta and had a SERIOUS error, rendering the phone unusable. I charged it to 60% and kept it plugged in while updating. While updating, I restarted several times at the Apple logo, then at the Welcome screen, and it had quite a few bugs with low battery warnings. When I turned it on, I noticed I had 1% (I thought it was strange). When it was plugged in, it wouldn't charge; it only had 1% left, and it also restarted every 2 minutes. Off-plugged, it did exactly the same thing. In the end, I had to go back to iOS 18.5; I had no problems with this version.
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Jun ’25
CarPlay not working on iOS 26 beta
Just wanted to check here to see if anyone else is running into the issue of CarPlay not working at all on iOS 26 Beta 1, even with the update on Friday. I plug my phone in (wired) and CarPlay never shows up. I've seen a Reddit thread where other folks are seeing the same thing.
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515
Dec ’25
Unable to localize driver name or description
I am trying to localize the CFBundleDisplayName and OSBundleUsageDescription of a driver that is part of an app. I am able to use InfoPlist.strings files to localize the Bundle display name for the app, but when I try to use the same file as part of the driver, the name displayed in settings for the app does not change correctly. In fact, it seems to follow the default language set in the xcode project. If the default language is not included in the suite of InfoPlist.strings files, it seems to take the string from the info.plist file. sometimes it just seems to take the English version regardless of the default language or tablet language. Has anyone had success with this?
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Aug ’25
Trouble with OSDeclareDefaultStructors.
Hi guys! OK, reaching out for some help here. I am having all kinds of trouble with OSDeclareDefaultStructors. I have seriously been at this for nearly a week now and have come to the conclusion that I need to reach out for help from people that are more experience using Xcode. I believe entirely that my issue is just that I can't for whatever reason see how to set up includes and libraries and things like that. I have this line: OSDeclareDefaultStructors(NukeVirtualGamepad) No matter what I do, Xcode will not recognize OSDeclareDefaultStructors. The project builds a DriverKit &gt; Driver extension. I have literally tried absolutely everything with this. I am at a loss for words. I even set up a new blank project and it still will not recognize OSDeclareDefaultStructors. I did a lot of research and it looks like expo needs OSDeclareDefaultStructors in order for the extension to build with a binary in it instead of being just a codeless extension. Here is the code with the issue: #pragma once #include &lt;DriverKit/OSMetaClass.h&gt; #include &lt;HIDDriverKit/IOUserHIDDevice.h&gt; #include &lt;DriverKit/OSData.h&gt; class NukeVirtualGamepad : public IOUserHIDDevice { OSDeclareDefaultStructors(NukeVirtualGamepad) // The problem is right here! This line! public: // Keep it minimal; no 'override' keywords since the .h types may not mark them virtual bool init(); void free(); kern_return_t Start(IOService* provider); void Stop (IOService* provider); OSData* newReportDescriptor(); // (Optional) helper you’ll use later to inject input matching your report kern_return_t PostInput(uint16_t buttons, int8_t x, int8_t y); }; I do have to mention to everyone that I am still very new with Xcode. So there is a ton that I don't know yet or might be misunderstanding. Has anyone seen this before? Thank you in advance.
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Aug ’25
How to sending capability requests.
I want to create a DriverKit driver and send vendor-specific commands to the storage device. Since UserClient is required to access the DriverKit driver from the app, I am attempting to implement it by referring to the following sample code. [Communicating between a DriverKit extension and a client app] I want to add com.apple.developer.driverkit.allow-any-userclient-access to the driver's Entitlements, submit a Capability Request on the developer site, and create a Provisioning Profile. However, I don't know how to enable com.apple.developer.driverkit.allow-any-userclient-access. I am entering the following information in the “Request a System Extension or DriverKit Entitlement” form. Which entitlement are you applying for? : DriverKit Entitlement Which DriverKit entitlements do you need? : UserClient Access UserClient Bundle IDs : [Bundle ID of MyDriver] Describe your apps and how they’ll use these entitlements. : testing sample code However, even if this request is accepted, I believe only MyDriver will be permitted. How can I grant access to all UserClients?
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Nov ’25
How to Symbolicate an Apple Silicon Panic?
Investigating a kernel panic, I discovered that Apple Silicon Panic traces are not working with how I know to symbolicate the panic information. I have not found proper documentation that corrects this situation. Attached file is an indentity-removed panic, received from causing an intentional panic (dereferencing nullptr), so that I know what functions to expect in the call stack. This is cut-and-pasted from the "Report To Apple" dialog that appears after the reboot: panic_1_4_21_b.txt To start, I download and install the matching KDK (in this case KDK_14.6.1_23G93.kdk), identified from this line: OS version: 23G93 Kernel version: Darwin Kernel Version 23.6.0: Mon Jul 29 21:14:04 PDT 2024; root:xnu-10063.141.2~1/RELEASE_ARM64_T8122 Then start lldb from Terminal, using this command: bash_prompt % lldb -arch arm64e /Library/Developer/KDKs/KDK_14.6.1_23G93.kdk/System/Library/Kernels/kernel.release.t8122 Next I load the remaining scripts per the instructions from lldb: (lldb) settings set target.load-script-from-symbol-file true I need to know what address to load my kext symbols to, which I read from this line of the panic log, after the @ symbol: com.company.product(1.4.21d119)[92BABD94-80A4-3F6D-857A-3240E4DA8009]@0xfffffe001203bfd0->0xfffffe00120533ab I am using a debug build of my kext, so the DWARF symbols are part of the binary. I use this line to load the symbols into the lldb session: (lldb) addkext -F /Library/Extensions/KextName.kext/Contents/MacOS/KextName 0xfffffe001203bfd0 And now I should be able to use lldb image lookup to identify pointers on the stack that land within my kext. For example, the current PC at the moment of the crash lands within the kext (expected, because it was intentional): (lldb) image lookup -a 0xfffffe001203fe10 Which gives the following incorrect result: Address: KextName[0x0000000000003e40] (KextName.__TEXT.__cstring + 14456) Summary: "ffer has %d retains\n" That's not even a program instruction - that's within a cstring. No, that cstring isn't involved in anything pertaining to the intentional panic I am expecting to see. Can someone please explain what I'm doing wrong and provide instructions that will give symbol information from a panic trace on an Apple Silicon Mac? Disclaimers: Yes I know IOPCIFamily is deprecated, I am in process of transitioning to DriverKit Dext from IOKit kext. Until then I must maintain the kext. Terminal command "atos" provides similar incorrect results, and seems to not work with debug-built-binaries (only dSYM files) Yes this is an intentional panic so that I can verify the symbolicate process before I move on to investigating an unexpected panic I have set nvram boot-args to include keepsyms=1 I have tried (lldb) command script import lldb.macosx but get a result of error: no images in crash log (after the nvram settings)
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Apr ’25
DriverKit IOUserSCSIPeripheralDeviceType00: kernel panic when setPowerState exceeds 20 seconds
We have an IOUserSCSIPeripheralDeviceType00 class DEXT supporting USB attached devices. With some high-capacity drives, the default setPowerState can exceed 20s to complete. This triggers a kernel panic, although this drive behavior is not unexpected. With a kernel extension implementing similar functionality we see no such problem as it appears from reading of Apple open source the timeout was 100s. What changes will allow setPowerState to complete without the kernel panic? kernel panic report excerpt attached. panic-full-2025-09-04-063127.0003.txt
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221
Activity
Oct ’25
DriverKit DEXT Logs Only Once, Subsequent Logs Are Lost Despite Normal Functionality
Hello everyone, I've encountered a very strange and persistent logging issue with my DriverKit DEXT and would appreciate any insights from the community. [Problem Summary] My DriverKit DEXT, along with its companion Swift app, is functionally working perfectly. I can repeatedly call methods in the DEXT from the app (e.g., a Ping-Pong test and a StaticProcessInbandTask call) and receive the correct response every time. However, the os_log messages within my IOUserClient subclass are only successfully recorded for the very first set of interactions. After that, all subsequent logs are completely missing. What's even stranger is that all successfully recorded logs are attributed to the kernel: process, even for purely user-space methods like ExternalMethod. [Development Environment] macOS: 15.7.1 Xcode: 16.4 Hardware: MacBook Pro M1 DEXT Logging Macro (Log.h): #include <os/log.h> #define Log(fmt, ...) \ do { \ os_log(OS_LOG_DEFAULT, "[%{public}s] " fmt, __FUNCTION__, ##__VA_ARGS__); \ } while (0) [Steps to Reproduce & Observed Behavior] The DEXT is successfully loaded via the companion app. I click the "Ping-Pong" button, then the "Process InBand" button in the app. The app's UI log correctly shows that the request was sent and a successful response was received from the DEXT. I repeat step 2 multiple times. Each interaction works flawlessly from the app's perspective. I then use the log show command to export the logs from this period, for example: log show --last 5m | grep "com.accusys.Acxxx.driver" > dext_logs.txt Observed Result (Log Content): In the dext_logs.txt file, I can only see the logs from the very first Ping-Pong and the very first Process InBand call. All subsequent, successful operations leave no trace in the logs. kernel: (com.accusys.Acxxx.driver.dext) [ExternalMethod] // { --- kernel: (com.accusys.Acxxx.driver.dext) [ExternalMethod] // --- } kernel: (com.accusys.Acxxx.driver.dext) [StaticPingPong] // { --- kernel: (com.accusys.Acxxx.driver.dext) [StaticPingPong] // --- } kernel: (com.accusys.Acxxx.driver.dext) [ExternalMethod] // { --- kernel: (com.accusys.Acxxx.driver.dext) [ExternalMethod] // --- } kernel: (com.accusys.Acxxx.driver.dext) [StaticProcessInbandTask] // { --- kernel: (com.accusys.Acxxx.driver.dext) [StaticProcessInbandTask] // --- } <--- END OF FILE (No new logs appear after this point) ---> [Core Questions] Why are logs in IOUserClient subclass only recorded once? Given the DEXT is clearly still running and processing requests, why would os_log calls only succeed in writing to the system log database on the first interaction? Why are all logs attributed to the kernel? Why would logs from 100% user-space code like ExternalMethod and StaticPingPong be attributed to the kernel process? [Solutions Attempted That Did Not Work] I have verified with ps aux that the DEXT process (com.accusys.Acxxx.driver) is running continuously in the background and has not crashed. Attempted to force-restart the logging service with sudo killall logd, but the issue persists. Performed the most thorough reset possible using systemextensionsctl reset followed by a full reboot, then reinstalled the DEXT. The issue remains exactly the same. Thank you for any possible help or suggestions Best, Charles
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199
Activity
Oct ’25
How to completely uninstall the old kext driver?
Hi, On macOS 11 and earlier versions, we provided users with the following script to uninstall our kext driver: sudo pkgutil --only-files --files com.magewell.ProCapture | tr '\n' '\0' | xargs -n 1 -0 sudo rm -vf sudo pkgutil --only-dirs --files com.magewell.ProCapture | grep ProCapture[^/]*$ | tr '\n' '\0' | xargs -n 1 -0 sudo rm -rvf sudo pkgutil --forget com.magewell.ProCapture sudo kextcache -system-caches However, this script no longer works on macOS 13 and returns the following error: It looks like you're trying to update the system caches. As of macOS 11, the personality cache is no longer in use for keeping kext matching information up-to-date. For more information, see `man kmutil`. This indicates we can no longer use kextcache -system-caches to clear our driver cache. This creates an issue where even after installing the new dext driver, the dext driver cannot run due to the presence of the old kext driver. We've tried various methods but haven't been able to completely uninstall the old kext driver - after every new system update, the old kext reappears. The specific process is as follows: This is the sequence I followed in my latest test - Device is running macOS 13 Ventura w/ 4247 Pro Capture kext driver installed kmutil inspect | grep -i magewell - this returns references to the kext files in /Library/Extensions, which is expected because I have not yet removed the 4247 kext driver - then I ran the following combination of your removal script and my removal steps: cd / sudo rm -r /Library/Extensions/ProCaptureDriver.kext sudo rm -r /Library/Extensions/ProCaptureEvent.kext sudo rm /System/Volumes/Preboot/*/boot/*/System/Library/Caches/com.apple.kernelcaches/kernelcache.auxkc* sudo pkgutil --only-files --files com.magewell.ProCapture | tr '\n' '\0' | xargs -n 1 -0 sudo rm -vf sudo pkgutil --only-dirs --files com.magewell.ProCapture | grep ProCapture[^/]*$ | tr '\n' '\0' | xargs -n 1 -0 sudo rm -rvf sudo pkgutil --forget com.magewell.ProCapture sudo kextcache --clear-staging sudo kcditto sudo kmutil install --update-preboot sudo shutdown -r now - After this I ran 'kmutil inspect | grep -i magewell' and got no results, which seems good but... - then I ran the upgrade to macOS 15.7 Sequoia - Afterwards I ran 'kmutil inspect | grep -i magewell' and it returned references to the old /Library/Extensions kexts again, although the files no longer exist in /Library/Extensions - I then ran my cleanup process again (slightly different for Sequoia-available commands): sudo rm /System/Volumes/Preboot/*/boot/*/System/Library/Caches/com.apple.kernelcaches/kernelcache.auxkc* sudo kextcache --clear-staging sudo kmutil rebuild sudo kcditto sudo kmutil install --update-preboot sudo shutdown -r now - Then I ran 'kmutil inspect | grep -i magewell' and got no results again - As a next test I ran a minor update to macOS 15.7.1, then ran 'kmutil inspect | grep -i magewell' and the references to the old kexts came back again We have indeed identified a solution to address this issue: kmutil trigger-panic-medic --volume-root /Volumes/<YourVolumeName> However, this method requires booting into Recovery Mode, which is unacceptable for many of our customers. Especially for those who need bulk remote management, having personnel physically operate each machine one by one is simply not feasible. Therefore, is there a method to completely uninstall the kext driver while in normal mode? Thank you!
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279
Activity
Oct ’25
[DriverKit SCSI] SCSI probe stalls for Target ID > 0 with IOUserSCSIParallelInterfaceController
Hello everyone, We are migrating a KEXT storage driver to DriverKit. In our KEXT, we use a "one LUN = one Target" model and successfully create multiple targets in a loop during initialization. We are now trying to replicate this architecture in our DEXT. The issue is that only Target 0 is fully probed and mounted. For Target 1, the lifecycle silently stops after the first TEST UNIT READY command is successfully acknowledged. The macOS SCSI layer never sends any subsequent probe commands (like INQUIRY) to this target. The failure sequence for Target 1, observed from our logs (regardless of whether Target 0 is created), is as follows: AsyncCreateTargetForID(1) -> UserInitializeTargetForID(1) (Succeeds) UserProcessParallelTask(Target: 1, Opcode: TUR) (Succeeds) The DEXT correctly acknowledges the TUR command for Target 1 by returning kSCSITaskStatus_CHECK_CONDITION with UNIT ATTENTION in the Sense Data (Succeeds) <-- Breakpoint --> UserProcessParallelTask(Target: 1, Opcode: INQUIRY) (Never happens) Through log comparison, we have confirmed that the DEXT's response to the TUR command for Target 1 is identical to the successful KEXT's response. We have tried creating only Target 1 (skipping Target 0 entirely), but the behavior is exactly the same -> the probe still stalls after the TUR. We initially suspected a race condition caused by consecutive calls to AsyncCreateTargetForID(). We attempted several methods to ensure that targets are created sequentially, such as trying to build a "creation chain" using OSAction completion handlers. However, these attempts were unsuccessful due to various compilation errors and API misunderstandings. In any case, this "race condition" theory was ultimately disproven by our experiment where creating only Target 1 still resulted in failure. We would like to ask two questions: Is our inability to have a Target ID greater than 0 fully probed by macOS a bug in our own code, or could there be another reason we are unaware of? If we do indeed need a "one-after-another" creation mechanism for AsyncCreateTargetForID, what is the correct way to implement a "chained creation" using OSAction completion handlers in DriverKit? Thank you for any help or guidance. Best Regards, Charles
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327
Activity
Jan ’26
UserSendCDB fails due to permissions
I created a custom class that inherits from IOUserSCSIPeripheralDeviceType00 in the DriverKit SCSIPeripheralsDriverKit framework. When I attempted to send a vendor-specific command to a USB storage device using the UserSendCDB function of this class instance, the function returned the error: kIOReturnNotPrivileged (iokit_common_err(0x2c1)) // privilege violation However, when using UserSendCDB in the same way to issue standard SCSI commands such as INQUIRY or Test Unit Ready, no error occurred and the returned sense data was valid. Why is UserSendCDB able to send standard SCSI commands successfully, but vendor-specific commands return kIOReturnNotPrivileged? Is there any required entitlement, DriverKit capability, or implementation detail needed to allow vendor-specific CDBs? Below are the entitlements of my DriverKit extension: <dict> <key>com.apple.developer.driverkit.transport.usb</key> <array> <dict> <key>idVendor</key> <integer>[number of vendorid]</integer> </dict> </array> <key>com.apple.developer.driverkit</key> <true/> <key>com.apple.developer.driverkit.allow-any-userclient-access</key> <true/> <key>com.apple.developer.driverkit.allow-third-party-userclients</key> <true/> <key>com.apple.developer.driverkit.communicates-with-drivers</key> <true/> <key>com.apple.developer.driverkit.family.scsicontroller</key> <true/> </dict> If there is any additional configuration or requirement to enable vendor-specific SCSI commands, I would appreciate your guidance. Environment: macOS15.6 M2 MacBook Pro
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366
Activity
Jan ’26
RFID read
Hi! Following this ticket: https://developer.apple.com/forums/thread/808764?page=1#868010022 Is there any way to use the hardware RFID reading capabilities of an iPhone to read ISO15693 RF tags silently, and without a UI pop-up? Perhaps using other native iOS libraries than the NFC library? If not, is there a way for a business to request this feature be allowed in internally used apps only?
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400
Activity
Jan ’26
OSSystemExtensionsWorkspace on iPadOS
Hello! I have app (macos and iPadOS platforms) with empbedded DEXT. The DEXT executable runs fine on both platforms (ver 26.2). Trying to execute from iPad App code: let sysExtWs = OSSystemExtensionsWorkspace.shared let sysExts = try sysExtWs.systemExtensions(forApplicationWithBundleID: appBudleId) but always getting OSSystemExtensionError.Code.missingEntitlement error. Which entitlement am I missing? Thank You!
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465
Activity
1w
How to prevent the popup "The disk you attached was not readable by the computer" from appearing?
Hello! We develop a SAS driver and a service application for DAS devices. When users in our application create a RAID array on the device: On the 1st step, our dext driver mounts a new volume. At this step DiskUtil automatically tries to mount it. As there is no file system on the new volume - the MacOS system popup appears "The disk you attached was not readable by the computer" On the 2nd step our application creates the file system on this new volume. So we do not need this MacOS system popup to appear (as it may frustrate our users). We found a way to disable the global auto mount but this solution also impacts on other devices (which is not good). Are there any other possibilities to prevent the popup "The disk you attached was not readable by the computer" from appearing?
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288
Activity
Jan ’26
iOS printing – Finishing (Punch) options not applied for images unless a preset is selected
When printing image/photo files via AirPrint, selected finishing options (e.g., Punch) are not applied unless a preset is chosen. reproduction steps: Select an image on iOS Tap Print → choose printer/server Set Finishing Options → Punch Print Observed: Finishing options not applied IPP trace shows no finisher attributes in the request working scenario: Select any Preset (e.g., Color) before printing Finishing options are then included in IPP and applied Note: Issue does not occur when printing PDFs from iOS; finisher attributes are sent correctly. Is this expected AirPrint behavior for image jobs, or could this be a bug in how iOS constructs the IPP request for photos?
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Activity
2w
Kernel Panic: Power state transition (0 -> 2) timeout during DriverKit (DEXT) load sequence (IOUserSCSIParallelInterfaceController)
Hi Everyone, We are currently migrating a mature legacy KEXT to DriverKit for our PCIe SCSI storage controller (connected via Thunderbolt 3). During the DEXT load sequence, we have observed that the system automatically triggers a power state transition from State 0 (Off) to State 2 (On). However, this process results in a Kernel Panic due to a timeout after approximately 21 seconds. We have verified that our implementation of Start_Impl, UserInitializeController_Impl, and SetPowerState_Impl executes extremely fast, with a total execution time of less than one second. Specifically, SetPowerState_Impl returns kIOReturnSuccess immediately upon being called. Furthermore, our current Info.plist does not contain any IOPowerManagement dictionary or related keys. Despite the fast execution and the absence of explicit power management declarations in the plist, the kernel power management state machine (IOServicePM) still generates a 21-second timeout, leading to the following panic: Panic Log: panic(cpu 7 caller 0xfffffe0020be8fec): MySCSIDriver::setPowerState(0xfffffe2fb1a65c00 : 0xfffffe0020bfed88, 0 -> 2) timed out after 21257 ms @IOServicePM.cpp:5609 com.example.driver.dext: ( id: com.example.driver.dext; path: /Library/SystemExtensions/[UUID]/com.example.driver.dext; state: loaded ) Note on Previous Discussion: I would like to express my gratitude to Kevin from Apple DTS for the helpful discussion regarding the implementation of BundleParallelTask on the forums. Since then, we have shifted our development focus toward completing the overall management ecosystem, delivering a comprehensive operational interface for users, and handling specific user environments and behaviors. Our current priority is ensuring system stability—specifically resolving these Thunderbolt-related power management issues (sleep/wake)—to prepare the product for upcoming testing. I remain very grateful for the guidance provided on batch task optimization and intend to resume those optimizations once this critical stability baseline is secured. Technical Guidance Needed for PM Migration In our legacy KEXT, we utilized PMinit(), registerPowerDriver(), and joinPMtree() to precisely control the timing of power management registration. In transitioning to the DriverKit SDK, we have not found clear guidance on several key points: Standardized Migration Path: What is the recommended way to implement equivalent power management initialization (formerly PMinit) within a DriverKit subclass? In DriverKit, how should we replicate the behavior of manually calling registerPowerDriver and joinPMtree to ensure the driver is only monitored once the hardware is ready? Implicit Power Registration: Why does the system enforce a setPowerState(0 -> 2) transition on a subclass of IOUserSCSIParallelInterfaceController even when no IOPowerManagement dictionary is defined in the Info.plist? Is this a default behavior of the SCSI or PCI transport framework? Thunderbolt Specifics: Are there specific power proxying requirements or configurations for PCIe devices over Thunderbolt to avoid conflicts with the default IOPCIFamily power policies? Best Regards, Charles
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Activity
1w
Why don't my os_log entries show up until the second time my driver loads?
I'm in the process of writing a DriverKit USBHostInterface driver, and while I'm finally starting to get there, I've run into a bit of a frustration with logging. Naturally I have a liberal amount of os_log calls that I'm using to troubleshoot my driver. However I've noticed that they don't show up until after the first time my driver has loaded. Meaning, for example, suppose I make a new build of my driver and it's bundled user-mode app, install the bundle to /Applications, run the installer, verify it took with systemextensionsctl list, fire up Console and start streaming log entries, then plug in my device. I can see the log entries that show that my driver is loaded, etc., then a bunch of kernel -> log entries, but none of my Start method log entries. If I unplug my device and plug it in again, my log entries show up as expected. Why is this and, more importantly, how can I fix it? I'd like to see those log entries the first time the driver loads, if I could.
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Activity
6d
Supported way to expose an iPhone+controller as a macOS gamepad without restricted entitlements?
I’m prototyping a personal-use system that lets an iPhone with a physically attached controller act as an input device for a Mac. End goal: Use the iPhone as the transport and sensor host Use the attached physical controller for buttons/sticks Map the iPhone gyroscope to the controller’s right stick to get gyro aim in Mac games / cloud-streamed games such as GeForce NOW that don't support the gyro. What I’m trying to understand is whether Apple supports any path for this on macOS that does NOT require restricted entitlements or paid-program-only capabilities. What I’ve already found: CoreHID virtual HID device creation appears to require com.apple.developer.hid.virtual.device HIDDriverKit / system extensions appear to require Apple-granted entitlements as well GCVirtualController does not seem to solve the problem because I need a controller-visible device that other apps can see, not just controls inside my own app So my concrete question is: Is there any supported, entitlement-free way for a personal macOS app to expose a game-controller-like input device that other apps can consume system-wide? If not, is the official answer that this class of solution necessarily requires one of: CoreHID with restricted entitlement HIDDriverKit/system extension entitlement some other Apple-approved framework or program I’m missing I’m not asking about App Store distribution. This is primarily for local/personal use during development. I’m trying to understand the supported platform boundary before investing further. Any guidance on the recommended architecture for this use case would be appreciated.
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Activity
2d
Neither macOS 14.7 "Standard" 'AppleUserHIDEventDriver' Matching Driver Nor Custom HIDDriverKit Driver 'IOUserHIDEventService::dispatchDigitizerTouchEvent' API Work for a HID-standard Digitizer Touch Pad Device
I have been working on a multi-platform multi-touch HID-standard digitizer clickpad device. The device uses Bluetooth Low Energy (BLE) as its connectivity transport and advertises HID over GATT. To date, I have the device working successfully on Windows 11 as a multi-touch, gesture-capable click pad with no custom driver or app on Windows. However, I have been having difficulty getting macOS to recognize and react to it as a HID-standard multi-touch click pad digitizer with either the standard Apple HID driver (AppleUserHIDEventDriver) or with a custom-coded driver extension (DEXT) modeled, based on the DTS stylus example and looking at the IOHIDFamily open source driver(s). The trackpad works with full-gesture support on Windows 11 and the descriptors seem to be compliant with the R23 Accessory Guidelines document, §15. With the standard, matching Apple AppleUserHIDEventDriver HID driver, when enumerating using stock-standard HID mouse descriptors, the device works fine on macOS 14.7 "Sonoma" as a relative pointer device with scroll wheel capability (two finger swipe generates a HID scroll report) and a single button. With the standard, matching Apple AppleUserHIDEventDriver HID driver, when enumerating using stock-standard HID digitizer click/touch pad descriptors (those same descriptors used successfully on Windows 11), the device does nothing. No button, no cursor, no gestures, nothing. Looking at ioreg -filtb, all of the key/value pairs for the driver match look correct. Because, even with the Apple open source IOHIDFamily drivers noted above, we could get little visibility into what might be going wrong, I wrote a custom DriverKit/HIDDriverKit driver extension (DEXT) (as noted above, based on the DTS HID stylus example and the open source IOHIDEventDriver. With that custom driver, I can get a single button click from the click pad to work by dispatching button events to dispatchRelativePointerEvent; however, when parsing, processing, and dispatching HID digitizer touch finger (that is, transducer) events via IOUserHIDEventService::dispatchDigitizerTouchEvent, nothing happens. If I log with: % sudo log stream --info --debug --predicate '(subsystem == "com.apple.iohid")' either using the standard AppleUserHIDEventDriver driver or our custom driver, we can see that our input events are tickling the IOHIDNXEventTranslatorSessionFilter HID event filter, so we know HID events are getting from the device into the macOS HID stack. This was further confirmed with the DTS Bluetooth PacketLogger app. Based on these events flowing in and hitting IOHIDNXEventTranslatorSessionFilter, using the standard AppleUserHIDEventDriver driver or our custom driver, clicks or click pad activity will either wake the display or system from sleep and activity will keep the display or system from going to sleep. In short, whether with the stock driver or our custom driver, HID input reports come in over Bluetooth and get processed successfully; however, nothing happens—no pointer movement or gesture recognition. STEPS TO REPRODUCE For the standard AppleUserHIDEventDriver: Pair the device with macOS 14.7 "Sonoma" using the Bluetooth menu. Confirm that it is paired / bonded / connected in the Bluetooth menu. Attempt to click or move one or more fingers on the touchpad surface. Nothing happens. For the our custom driver: Pair the device with macOS 14.7 "Sonoma" using the Bluetooth menu. Confirm that it is paired / bonded / connected in the Bluetooth menu. Attempt to click or move one or more fingers on the touchpad surface. Clicks are correctly registered. With transducer movement, regardless of the number of fingers, nothing happens.
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Activity
Dec ’25
iOS 26 iPhone won't charge and keeps restarting.
I have an iPhone 14 Pro. I downloaded the iOS 26 beta and had a SERIOUS error, rendering the phone unusable. I charged it to 60% and kept it plugged in while updating. While updating, I restarted several times at the Apple logo, then at the Welcome screen, and it had quite a few bugs with low battery warnings. When I turned it on, I noticed I had 1% (I thought it was strange). When it was plugged in, it wouldn't charge; it only had 1% left, and it also restarted every 2 minutes. Off-plugged, it did exactly the same thing. In the end, I had to go back to iOS 18.5; I had no problems with this version.
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Activity
Jun ’25
CarPlay not working on iOS 26 beta
Just wanted to check here to see if anyone else is running into the issue of CarPlay not working at all on iOS 26 Beta 1, even with the update on Friday. I plug my phone in (wired) and CarPlay never shows up. I've seen a Reddit thread where other folks are seeing the same thing.
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515
Activity
Dec ’25
Unable to localize driver name or description
I am trying to localize the CFBundleDisplayName and OSBundleUsageDescription of a driver that is part of an app. I am able to use InfoPlist.strings files to localize the Bundle display name for the app, but when I try to use the same file as part of the driver, the name displayed in settings for the app does not change correctly. In fact, it seems to follow the default language set in the xcode project. If the default language is not included in the suite of InfoPlist.strings files, it seems to take the string from the info.plist file. sometimes it just seems to take the English version regardless of the default language or tablet language. Has anyone had success with this?
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7
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243
Activity
Aug ’25
Trouble with OSDeclareDefaultStructors.
Hi guys! OK, reaching out for some help here. I am having all kinds of trouble with OSDeclareDefaultStructors. I have seriously been at this for nearly a week now and have come to the conclusion that I need to reach out for help from people that are more experience using Xcode. I believe entirely that my issue is just that I can't for whatever reason see how to set up includes and libraries and things like that. I have this line: OSDeclareDefaultStructors(NukeVirtualGamepad) No matter what I do, Xcode will not recognize OSDeclareDefaultStructors. The project builds a DriverKit &gt; Driver extension. I have literally tried absolutely everything with this. I am at a loss for words. I even set up a new blank project and it still will not recognize OSDeclareDefaultStructors. I did a lot of research and it looks like expo needs OSDeclareDefaultStructors in order for the extension to build with a binary in it instead of being just a codeless extension. Here is the code with the issue: #pragma once #include &lt;DriverKit/OSMetaClass.h&gt; #include &lt;HIDDriverKit/IOUserHIDDevice.h&gt; #include &lt;DriverKit/OSData.h&gt; class NukeVirtualGamepad : public IOUserHIDDevice { OSDeclareDefaultStructors(NukeVirtualGamepad) // The problem is right here! This line! public: // Keep it minimal; no 'override' keywords since the .h types may not mark them virtual bool init(); void free(); kern_return_t Start(IOService* provider); void Stop (IOService* provider); OSData* newReportDescriptor(); // (Optional) helper you’ll use later to inject input matching your report kern_return_t PostInput(uint16_t buttons, int8_t x, int8_t y); }; I do have to mention to everyone that I am still very new with Xcode. So there is a ton that I don't know yet or might be misunderstanding. Has anyone seen this before? Thank you in advance.
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230
Activity
Aug ’25
How to sending capability requests.
I want to create a DriverKit driver and send vendor-specific commands to the storage device. Since UserClient is required to access the DriverKit driver from the app, I am attempting to implement it by referring to the following sample code. [Communicating between a DriverKit extension and a client app] I want to add com.apple.developer.driverkit.allow-any-userclient-access to the driver's Entitlements, submit a Capability Request on the developer site, and create a Provisioning Profile. However, I don't know how to enable com.apple.developer.driverkit.allow-any-userclient-access. I am entering the following information in the “Request a System Extension or DriverKit Entitlement” form. Which entitlement are you applying for? : DriverKit Entitlement Which DriverKit entitlements do you need? : UserClient Access UserClient Bundle IDs : [Bundle ID of MyDriver] Describe your apps and how they’ll use these entitlements. : testing sample code However, even if this request is accepted, I believe only MyDriver will be permitted. How can I grant access to all UserClients?
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154
Activity
Nov ’25
Can iOS communicates with a non-MFi 3rd party device over USB-C?
Hello forum, I'm trying to build communications between a non-MFi HID device (say, a keyboard with a USB-C port) and an iOS device over a MFi-licensed cable with Swift, what framework would you suggest? The USB-C cable is MFi-licensed. The keyboard is not MFi-licensed.
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1k
Activity
Jun ’25
How to Symbolicate an Apple Silicon Panic?
Investigating a kernel panic, I discovered that Apple Silicon Panic traces are not working with how I know to symbolicate the panic information. I have not found proper documentation that corrects this situation. Attached file is an indentity-removed panic, received from causing an intentional panic (dereferencing nullptr), so that I know what functions to expect in the call stack. This is cut-and-pasted from the "Report To Apple" dialog that appears after the reboot: panic_1_4_21_b.txt To start, I download and install the matching KDK (in this case KDK_14.6.1_23G93.kdk), identified from this line: OS version: 23G93 Kernel version: Darwin Kernel Version 23.6.0: Mon Jul 29 21:14:04 PDT 2024; root:xnu-10063.141.2~1/RELEASE_ARM64_T8122 Then start lldb from Terminal, using this command: bash_prompt % lldb -arch arm64e /Library/Developer/KDKs/KDK_14.6.1_23G93.kdk/System/Library/Kernels/kernel.release.t8122 Next I load the remaining scripts per the instructions from lldb: (lldb) settings set target.load-script-from-symbol-file true I need to know what address to load my kext symbols to, which I read from this line of the panic log, after the @ symbol: com.company.product(1.4.21d119)[92BABD94-80A4-3F6D-857A-3240E4DA8009]@0xfffffe001203bfd0->0xfffffe00120533ab I am using a debug build of my kext, so the DWARF symbols are part of the binary. I use this line to load the symbols into the lldb session: (lldb) addkext -F /Library/Extensions/KextName.kext/Contents/MacOS/KextName 0xfffffe001203bfd0 And now I should be able to use lldb image lookup to identify pointers on the stack that land within my kext. For example, the current PC at the moment of the crash lands within the kext (expected, because it was intentional): (lldb) image lookup -a 0xfffffe001203fe10 Which gives the following incorrect result: Address: KextName[0x0000000000003e40] (KextName.__TEXT.__cstring + 14456) Summary: "ffer has %d retains\n" That's not even a program instruction - that's within a cstring. No, that cstring isn't involved in anything pertaining to the intentional panic I am expecting to see. Can someone please explain what I'm doing wrong and provide instructions that will give symbol information from a panic trace on an Apple Silicon Mac? Disclaimers: Yes I know IOPCIFamily is deprecated, I am in process of transitioning to DriverKit Dext from IOKit kext. Until then I must maintain the kext. Terminal command "atos" provides similar incorrect results, and seems to not work with debug-built-binaries (only dSYM files) Yes this is an intentional panic so that I can verify the symbolicate process before I move on to investigating an unexpected panic I have set nvram boot-args to include keepsyms=1 I have tried (lldb) command script import lldb.macosx but get a result of error: no images in crash log (after the nvram settings)
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Activity
Apr ’25