Team-scoped keys introduce the ability to restrict your token authentication keys to either development or production environments. Topic-specific keys in addition to environment isolation allow you to associate each key with a specific Bundle ID streamlining key management. For detailed instructions on accessing these features, read our updated documentation on establishing a token-based connection to APNs.

Hi there, I have a popular open source app called Foqos. What I'm finding in iOS 26 (might even effect older versions) is that when using the webcontent api within Managed settings as the following: store.webContent.blockedByFilter = .specific(domains) It doesn't work on Safari, but does work on third party applications like chrome, firefox, etc. But when using the all and exception enum like the following store.webContent.blockedByFilter = .all(except: domains) This does work on Safari This is pretty inconsistent behavior of the API and should be fixed to match the documentation. Documentation does not mention anything about Safari limitations Again source code is open: https://github.com/awaseem/foqos You can run the app yourself and find the same issues. Is anyone else experiencing this?

Are the Wifi-Aware's WAEndpoint's discovered ephemeral? I'm trying to understand what's the best way to reconnect a disconnected WifiAware connection - Can I just cache the endpoint and start a new connection with the same endpoint or do I need to browse again and get a new WAEndpoint? My use case requires both WifiAware connection to another device and the devices also need to be connected to infrastructure wifi most of the time. I'm concerned about the WifiAware's connection having any impact on infrastructure wifi. What is the impact on the infrastructure wifi here in comparison to using the Apple peer to peer wifi(That Multipeer framework or Network framework use)?

On macOS 26, I've run into a situation when a user “customizes” a folder icon with Finder by assigning/changing an SF Symbol or an emoji, QLThumbnailGenerator keeps returning the stale initially retrieved folder icon (no matter whether it had been customized or not) until my app quits. After the app is re-launched, the icon is correctly retrieved once again. let generator = QLThumbnailGenerator.shared let size: CGSize = CGSize(width: 64, height: 64) let request = QLThumbnailGenerator.Request(fileAt: url, size: size, scale: NSScreen.main!.backingScaleFactor, representationTypes: .icon) request.iconMode = true do { let thumb = try await generator.generateBestRepresentation(for: request) thumb.nsImage.size = size return thumb.nsImage } catch { print("generateThumbnail: \(error)") return nil } It seems like the QuickLook Thumbnailing cache does not invalidate automatically upon folder customization. Is there any way to manually invalidate the QuickLook Thumbnailing cache?

The device I am trying to develop a firmware updater for is an NVMe drive with a USB4 interface. It can connect in USB4 mode (tunneled NVMe), in USB 3 mode or in USB 2 mode. In USB 2 and USB 3 mode, the device descriptor shows one interface with two alternates. Alternate 0 uses the bulk-only protocol, with one IN and one OUT pipe. Alternate 1 uses the UAS protocol, with two IN and two OUT pipes. I use identical code in my driver to send custom CDBs. I can see using IORegistryExplorer that in USB 2 mode, macOS chooses alternate 0, the bulk-only protocol. My custom CDBs and their accompanying data pay loads are put on the bus, more or less as expected. In USB 3 mode, macOS chooses alternate 1, the UAS protocol. My custom CDB is put on the bus, but no payload data is transferred. Is this expected behavior? If so, is there a way to force the OS to choose alternate 0 even when on USB 3, perhaps with another dext? I'll file a bug about this when Feedback Assistant lets me.

Hi everyone, After updating to Xcode 16.4, my StoreKit configuration stopped working. Whenever I run the app with a .storekit file set as the active scheme, I immediately get this alert: “The file has been changed. Do you want to save your changes or revert to the file on disk?” No matter if I choose Save Anyway or Revert, StoreKit testing does not work - the purchases are not simulated, and the scheme is basically broken. This issue didn’t exist in Xcode 15.4 - the same StoreKit configuration file works fine there. What I tried so far: Clearing Derived Data - no effect Making sure no scripts/tools modify the .storekit file - still happens Restarting Xcode and macOS - no change Environment: Xcode 16.4 Happens in both Simulator and on device Reproducible 100% Has anyone else seen this in 16.4? Any known workarounds until Apple fixes it? Thanks!

AppleScript for the Music app no longer supports the current track event. Before macOS Tahoe, running the following script in Script Editor would return the current track information: tell application "Music" return name of current track end tell However, when I run this script on a device with macOS 26 Tahoe, I receive this error: "Result: error "Music got an error: Can’t get name of current track." number -1728 from name of current track” I've tested this extensively, and here are my findings: Going to the “songs” tab and playing something from there makes everything work. Playing any song directly will make it work with current track UNLESS this song is NOT in your Music library (either added through Apple Music or uploaded). If you play a song not in your library, current track is not updated even if you clicked on it specifically. Playing an album (in your library obviously) makes all the tracks within it appear in current track until autoplay takes over. Any autoplayed track won’t appear in current track even if in your library (unless: see the last bulletpoint) Music played through the “songs” tab all appear in current track even if autoplay kicks in. I assume this is because this tab is an iTunes legacy (visually and under the hood) and doesn’t use the modern autoplay. This tab also won’t play non-library songs unlike the “albums” tab which seems to use the correct autoplay and suffers the same symptoms as the “recently added”, “home”, “radio”, etc… tabs. Is this a bug, or has Apple simply deprecated this functionality?

as i want to tract activity of iphone user using core motion framework , guide me through .

Hi, This post is coming from frustration of working on using BGContinuedProcessingTask for almost 2 weeks, trying to get it to actually complete in the background after the app is backgrounded. My process will randomlly finish and not finish and have no idea why. I'm properly using and setting task?.progress.totalUnitCount = [some number] task?.progress.completedUnitCount = [increment as processed] I know this, because it all looks propler as long as the app insn't backgrounded. So it's not a progress issue. The task will ALWAYS complete. The device has full power, as it is plugged in as I run from within Xcode. So, it's not a power issue. Yes, the process will take a few minutes, but I thought that is BGContinuedProcessingTask purpose in iOS 26. For long running process that a user could place in the background and leave the app, assuming the process would actually finish. Why bother introducing a feature that only works with short tasks that don't actually need long running time in the first place.

Hello, Back in January 2024, I filed a bug report regarding a cache being kept by the macOS Wallpaper Agent. This cache contains every image ever set as a users wallpaper, and at the time the issue was reported, it never cleared, leaving hundreds of gigabytes wasted on users disks in some cases. FB13536275 This issue was ultimately fixed in macOS 15.1 beta 6, and remained fixed for the duration of macOS 15. The fix was excellent - the cache was reduced to storing just 2-3 days worth of images. Sadly, we've discovered that this issue is back in macOS Tahoe. The cache has moved locations, and once again is not clearing. We have filed this bug again, less than a year after it was first fixed: FB20636593 We develop an app called 24 Hour Wallpaper that keeps the wallpaper in sync with the time of day. This necessitates that the app regularly changes the wallpaper, which sadly now results in an infinitely growing and useless cache of BMP files generated by the system. As we waited 10 months for this to get fixed the first time, we expect to wait at least that long to get it fixed again, and have no confidence that it will stay fixed because the last fix lasted less than a year. This leaves us in a bad position, as people can't use our app without the cache growing arbitrarily and ultimately completely filling their disk. We've already had customers call Apple to complain about this, and the good news is that the support agents understand that this is a problem with macOS, not with our app. What we've decided to do is add a feature to the app that monitors the size of this cache and periodically deletes it. We're required to get the users permission the first time to do this, but after that the permission is cached, so the app can keep the cache folder clean regardless of if macOS is doing it's job or not. We haven't seen any side effects or problems as a result of doing this. We've seen other apps like CleanMyMac do this without any problems. We're wondering if there is anything we should be aware of regarding this caches behavior before releasing this flushing feature. Thanks for your time, -josh

We are trying to figure out a strange issue. Our app has not changed for at least 10 months but my devices and the QA tester device have all stopped receiving push/call notifications for twilio voip The twilio credential and apple voip services certificate are in date and valid It is pointing to the correct bundle id and topic (not changed configuration for years) token passed in to TwilioVoiceSDK.register() is retrieved from PKPushRegistry as per guide Running locally the Twilio Voice SDK successfully registers and retrieves APNs token What is interesting is if I log in with exactly the same client account on an iOS 18.5 device (and an older iPad) call notifications work perfectly (I have made sure all focus modes/dnd are off and notification settings are identical) The only changes myself and QA have made recently is minor iOS 18 version updates - 18.6.2 and 18.7.1 These now receive Invalid device token from APNs when Twilio attempts to create a call/voip notification for the user identity Our devices sometimes switch environments test/prod so I installed the app cleanly on a borrowed 18.6.2 device and got the exact same issue We have tested on these devices most of the year with no issues. I have been in touch with twilio support and added code to explicitly unregister and re register on an affected device to clear any bindings but it didn't help. Have apple made any changes in PushKit or token behaviour for later versions of iOS 18? Thanks

Hi, I have been recently debugging the BGContinuedProcessingTask API and encountered some of the following issues. I hope you can provide some answers: First, let me explain my understanding of this API. I believe its purpose is to allow an app to trigger tasks that can be represented with progress indicators and require a certain amount of time to complete. After entering the background, these tasks can continue to be completed through the BGContinuedProcessingTask, preventing the system from terminating them before they are finished. In the launchHandler of the registration process, we only need to do a few things: Determine whether the actual business processing is still ongoing. Update the progress, title, and subtitle. Handle the expirationHandler. Set the task as completed. Here are some issues I encountered during my debugging process: After I called register and submit, the BGContinuedProcessingTask could not be triggered. The return values from my API calls were all normal. I tried different device models, and some could trigger the task normally, such as the 15 Pro Max and 12 Pro Max. However, there were also some models, such as the 17 Pro, 15 Pro, and 15, that could not trigger the task properly. Moreover, there was no additional error information to help locate the issue. The background task failed unexpectedly, but my app was still running normally. As I mentioned above, my launchHandler only retrieves the actual business status and updates it. If a background task fails unexpectedly while the app is still running normally, it can mislead users and degrade the user experience of the app. Others have also mentioned the issue of inconsistent behavior on devices that do not support Dynamic Island. On devices that support Dynamic Island, when a task is triggered in the foreground, the app does not immediately display a pop-up notification within the app. However, on devices that do not support Dynamic Island, the app directly displays a pop-up notification within the app, and this notification does not disappear when switching between different screens within the same app. The user needs to actively swipe up to dismiss it. I think this experience is too intrusive for users. I would like to know whether this will be maintained in the future or if there is a plan to fix it. On devices that do not support Dynamic Island, using the beta version 26.1 of the system, if the system is in dark mode but the app triggers a business interface in white, the pop-up notification will have the same color as the current page, making it difficult to read the content inside the pop-up. Users can actively stop background tasks by using the stop button, or the system can also stop tasks automatically when resources are insufficient or when a task is abnormal. However, according to the current API, all these actions are triggered through the expirationHandler. Currently, there is no way to distinguish whether the task was stopped by the user, by the system due to resource insufficiency, or due to an abnormal task. I would like to know whether there will be more information provided in the future to help distinguish these different scenarios. I believe that the user experience issues mentioned in points 2 and 3 are the most important. Please help to answer the questions and concerns above. Thank you!

I'm trying to handle the serverRecordChanged return code you get in CKError when you have a conflict and your using the savePolicy of ifServerRecordUnchanged. According to the CKError.Code.serverRecordChanged documentation, I should be receiving all three records that I need to do a 3-way merge. The problem is that the ancestorRecord (CKRecordChangedErrorAncestorRecordKey can also be used to look it up in the userInfo) doesn't actually contain a record. It only contains the record metadata. Is there something I need to be doing to get the full ancestorRecord in the CKError? If not is it possible to query iCloud for the ancestorRecord? Given that iCloud has the change history (as I understand it), then it is theoretically possible. I just don't know how to do it if it is possible. Are 3-way merges even possible? The design of the serverRecordChanged looks like that is the intent, but I can't see how to do it with the data that CloudKit is providing.

Hello all, I am new to implementing payments in an app, and thus completely at sea here. I have created a small app that I have set a one-time (non-consumable) payment for a premium version. In the Xcode simulator (on all platforms) and on any physical test devices I have tried, the payment works as expected. I have a sandbox account and various test accounts, both dummy and actual real accounts (friends and family). Everywhere everything works perfectly fine. Yet, when I submit for review I get a rejection with this contents: We found that your in-app purchase products exhibited one or more bugs which create a poor user experience. Specifically, the app still failed to load the in-app purchase. Please review the details and resources below and complete the next steps. Review device details: Device type: iPad Air (5th generation) OS version: iPadOS 18.6 Next Steps When validating receipts on your server, your server needs to be able to handle a production-signed app getting its receipts from Apple’s test environment. The recommended approach is for your production server to always validate receipts against the production App Store first. If validation fails with the error code "Sandbox receipt used in production," you should validate against the test environment instead. Additionally, note that the Account Holder must accept the Paid Apps Agreement in the Business section of App Store Connect before paid in-app purchases will function. Resources Learn how to set up and test in-app purchase products in >the sandbox environment. Learn more about validating receipts with the App Store. Steps I have done: I have signed all agreements and all bank account details are in order. Everything in the In-app-purchases section of the AppStoreConnect in an Active state. I have triple checked that the configuration of the in-app purchases is correct (product IDs, amounts, etc.) I have created test accounts and tested in sandbox What I don't understand from the reviewer's response is what receipts validation are they talking about? I have no payment servers (the whole concept of using Apple's in-app-purchases service is to not have to deal with my own payment implementation). The StoreKit documentation specifically reads: For each transaction that represents a current purchase, your app delivers the purchased products. To validate purchases, you can verify transactions on your server, or rely on StoreKit’s verification. So now I am confused. The reviewer's response is so vague, and so completely deprived of details that I have no idea what to do... Does the problem concern the product purchase trigger and the that in production environment it does not trigger? Is it that I haven't implemented a receipt validation? Do I need to? Although the documentation mentions that it can be done by StoreKit, I couldn't find anything concerning how to do it :( Can someone give me a hand please? Cheers, Alex

When my AppShortcut phrase is: "Go (.$direction) with (.applicationName)" Then everything works correctly, the AppIntent correctly receives the parameter. But when my phrase is: "What is my game (.$direction) with (.applicationName)" The an alert dialog pops up saying: "Hey siri what is my game tomorrow with {app name} Do you want me to use ChatGPT to answer that?" The phrase is obviously heard correctly, and it's exactly what I've specified in the AppShortcut. Why isn't it being sent to my AppIntent? import Foundation import AppIntents @available(iOS 17.0, *) enum Direction: String, CaseIterable, AppEnum { case today, yesterday, tomorrow, next static var typeDisplayRepresentation: TypeDisplayRepresentation { TypeDisplayRepresentation(name: "Direction") } static var caseDisplayRepresentations: [Direction: DisplayRepresentation] = [ .today: DisplayRepresentation(title: "today", synonyms: []), .yesterday: DisplayRepresentation(title: "yesterday", synonyms: []), .tomorrow: DisplayRepresentation(title: "tomorrow", synonyms: []), .next: DisplayRepresentation(title: "next", synonyms: []) ] } @available(iOS 17.0, *) struct MoveItemIntent: AppIntent { static var title: LocalizedStringResource = "Move Item" @Parameter(title: "Direction") var direction: Direction func perform() async throws -> some IntentResult { // Logic to move item in the specified direction print("Moving item \(direction)") return .result() } } @available(iOS 17.0, *) final class MyShortcuts: AppShortcutsProvider { static let shortcutTileColor = ShortcutTileColor.navy static var appShortcuts: [AppShortcut] { AppShortcut( intent: MoveItemIntent() , phrases: [ "Go \(\.$direction) with \(.applicationName)" // "What is my game \(\.$direction) with \(.applicationName)" ] , shortTitle: "Test of direction parameter" , systemImageName: "soccerball" ) } }

My app is a VoIP softphone for Mac that allows people to make phone calls to a regular phone numbers. The app exists since before Mac App Store. The app declares itself to the system as capable of handling tel: URLs. Until now, people could change the default handler for tel URLs in FaceTime settings (Default for calls). In macOS Tahoe 26, this doesn't seem to be possible any more. That option is gone from the FaceTime settings. Is it completely gone or has it been moved somewhere else? If there is no UI control for this any more, is it possible to change it programmatically?

Dear Apple engineers and DriverKit developers, We have developed a DriverKit (DEXT) driver for an HBA RAID controller. The RAID controller is connected to hosts through Thunderbolt (PCIe port of the Thunderbolt controller). We use an IO script to verify the developed driver. The test fails after a few (10-12) hours of running with an error: “BUG IN CLIENT OF LIBDISPATCH: dispatch_sync called on queue already owned by current thread”. We inspected the stack trace of the crash report. This error happens in the interrupt handler. Thread 5 Crashed: 0 libdispatch.dylib 0x19671aa8c __DISPATCH_WAIT_FOR_QUEUE__ + 484 1 libdispatch.dylib 0x19671a5d0 _dispatch_sync_f_slow + 152 2 DriverKit 0x195d3fc1c IODispatchQueue::DispatchSync_f(void*, void (*)(void*)) + 296 3 DriverKit 0x195d40860 IOInterruptDispatchSourceThread(void*) + 380 4 libsystem_pthread.dylib 0x1968a3738 _pthread_start + 140 5 libsystem_pthread.dylib 0x1968ac6c8 thread_start + 8 On our side we created 5 DispatchQueue(s) for the interrupt processing and configured 5 interrupt handlers using ConfigureInterrupts(kIOInterruptTypePCIMessagedX, 1, 5). It gives 5 interrupts, as requested and it is not clear what is the reason for the issue. Our code samples are below uint32_t configureInterrupts(uint32_t requested, uint32_t required)  {      const kern_return_t ret = ioPCIdevice->ConfigureInterrupts(kIOInterruptTypePCIMessagedX, required, requested);      if (ret != kIOReturnSuccess)          return 0;      uint64_t interruptType = 0;      uint32_t interruptsCount = 0;      uint32_t interruptIndex = 0;        for ( ;; ++interruptIndex) {          if (IOInterruptDispatchSource::GetInterruptType(ioPCIdevice, interruptIndex, &interruptType) != kIOReturnSuccess)              break;          if ((interruptType & kIOInterruptTypePCIMessagedX) == 0)              continue;          ++interruptsCount;      }      return interruptsCount;  }  ..... // Create DQs     for(int i = 0; i < maxInterrupts; ++i) {          ret = IODispatchQueue::Create(INTERRUPT_DQ_NAME, 0, 0, &ivars->interruptQueue[i]);          if (kIOReturnSuccess != ret || nullptr == ivars->interruptQueue[i]) {              GH_PRINT_ERR("Interrupts queue %d creation failed with error %d", i, ret);              return false;          }      } ..... // Link DQ with interrupt   for(int index = 0; index < maxInterrupts; ++ index) {      kern_return_t ret = CreateActionHandleInterruptRequest(size, &ivars->interruptActions[index]);      if (kIOReturnSuccess != ret) {          GH_PRINT_ERR("Create action for interrupt handler %u failed.", index);          return ;      }      ret = IOInterruptDispatchSource::Create(ivars->PCI_io.dev, index, ivars->interruptQueue[index], &ivars->interruptSources[index]);      if (kIOReturnSuccess != ret || nullptr == ivars->interruptSources[index]) {          GH_PRINT_ERR("Creating interrupt source %u failed for interrupt index %u.", index, index);          return ;      }      ret = ivars->interruptSources[index]->SetHandler(ivars->interruptActions[index]);      if (kIOReturnSuccess != ret) {          GH_PRINT_ERR("Setting the handler for interrupt source %u failed.", index);          return ;      }      ivars->contexts[index] = ivars->interruptActions[index]->GetReference();      }  ..... // definition for interrupt handler void    HandleInterruptRequest ( OSAction *action, uint64_t count, uint64_t time) TYPE (IOInterruptDispatchSource::InterruptOccurred);  Do you have any clue how we can fix this error? Or directions and ways for investigation? Please let us know if you need more details.

Hi everyone, I am having issues with all my MacOS devices (3 so far) and push notifications. My app is in development and when i send a Test APN (From the Push Notification Console) to any of my MacOS devices (using the device token), the log is "discarded as device was offline". Fun fact, if i run the command : sudo kill apsd I receive the previously "discarded" Push notification immediately. Is it a known bug or something is wrong in my configuration ? Note : my debugProfile.entitlements is fine and the value is set to "development", i have already reloaded my certificate by cleaning the project and rebuilding (according to ChatGPT) but nothing works... I am using Xcode 26.0.1 and MacOS 26.0.1 on my 3 different MacOS devices all having this issue. Thanks in advance, Tom

If I'm reading this guide correctly, macOS will automatically/implicitly startAccessingSecurityScopedResource for files opened via drag to Dock icon or NSOpenPanel. And I'm expected to call stopAccessingSecurityScopedResource to balance it once I'm done. Does that mean that if I don't, I'm leaking kernel resources as per the docs? If you fail to relinquish your access to file-system resources when you no longer need them, your app leaks kernel resources. If sufficient kernel resources leak, your app loses its ability to add file-system locations to its sandbox, such as with Powerbox or security-scoped bookmarks, until relaunched. What is this limit in practice for macOS and iOS? I've seen number ranging from 1000-2500. From my testing, iOS does not provide the same implicit startAccessingSecurityScopedResource when using UIDocumentPickerViewController. Is this a correct observation/per design? Now, in the cases where I'm creating an NSURL by resolving a saved bookmark, I'm expected to explicitly startAccessingSecurityScopedResource. Based on this, from what I can tell, this means that I can't universally call startAccessingSecurityScopedResource whenever I access a resource by URL, balanced with a stopAccessingSecurityScopedResource when done, as depending on how I got the URL it might already be implicitly started. Is this a correct observation? Do I need to explicitly check whether I'm on iOS (never implicit?), or macOS (sometimes implicit?), and selectively startAccessingSecurityScopedResource based on every call site that may give me a security-scoped file? If so, is there a complete list of the entrypoints that may give me such files (file dialog, drag and drop, etc)? Thanks!

Our app is developed for iOS, but some users also run it on macOS (as an iOS app via Apple Silicon). The app requires local network permission, which works perfectly on iOS. Previously, the connection also worked fine on macOS, but since the recent macOS update, the app can no longer connect to our device. Additionally, our app on macOS doesn't prompt for local network permission at all, whereas it does on iOS. Is this a known issue with iOS apps running on macOS? Has anyone else experienced this problem, or is there a workaround? Any help would be appreciated!

Hello everyone, I am migrating a KEXT for a SCSI PCI RAID controller (LSI 3108 RoC) to DriverKit (DEXT). While the DEXT loads successfully, I'm facing a DMA issue: an INQUIRY command results in a 0-byte disk because the data buffer received by the DEXT is all zeros, despite our firmware logs confirming that the correct data was prepared and sent. We have gathered detailed forensic evidence and would appreciate any insights from the community. Detailed Trace of a Failing INQUIRY Command: 1, DEXT Dispatches the Command: Our UserProcessParallelTask implementation correctly receives the INQUIRY task. Logs show the requested transfer size is 6 bytes, and the DEXT obtains the IOVA (0x801c0000) to pass to the hardware. DEXT Log: [UserProcessParallelTask_Impl] --- FORENSIC ANALYSIS --- [UserProcessParallelTask_Impl] fBufferIOVMAddr = 0x801c0000 [UserProcessParallelTask_Impl] fRequestedTransferCount = 6 2, Firmware Receives IOVA and Prepares Correct Data: A probe in our firmware confirms that the hardware successfully received the correct IOVA and the 6-byte length requirement. The firmware then prepares the correct 6-byte INQUIRY response in its internal staging buffer. Firmware Logs: -- [FIRMWARE PROBE: INCOMING DMA DUMP] -- Host IOVA (High:Low) = 0x00000000801c0000 DataLength in Header = 6 (0x6) --- [Firmware Outgoing Data Dump from go_inquiry] --- Source Address: 0x228BB800, Length: 6 bytes 0x0000: 00 00 05 12 1F 00 3, Hardware Reports a Successful Transfer, but Data is Lost: After the firmware initiates the DMA write to the Host IOVA, the hardware reports a successful transfer of 6 bytes back to our DEXT. DEXT Completion Log: [AME_Host_Normal_Handler_SCSI_Request] [TaskID: 200] COMPLETING... [AME_Host_Normal_Handler_SCSI_Request] Hardware Transferred = 6 bytes [AME_Host_Normal_Handler_SCSI_Request] - ReplyStatus = SUCCESS (0x0) [AME_Host_Normal_Handler_SCSI_Request] - SCSIStatus = SUCCESS (0x0) The Core Contradiction: Despite the firmware preparing the correct data and the hardware reporting a successful DMA transfer, the fDataBuffer in our DEXT remains filled with zeros. The 6 bytes of data are lost somewhere between the PCIe bus and host memory. This "data-in-firmware, zeros-in-DEXT" phenomenon leads us to believe the issue lies in memory address translation or a system security policy, as our legacy KEXT works perfectly on the same hardware. Compared to a KEXT, are there any known, stricter IOMMU/security policies for a DEXT that could cause this kind of "silent write failure" (even with a correct IOVA)? Alternatively, what is the correct and complete expected workflow in DriverKit for preparing an IOMemoryDescriptor* fDataBuffer (received in UserProcessParallelTask) for a PCI hardware device to use as a DMA write target? Any official documentation, examples, or advice on the IOMemoryDescriptor to PCI Bus Address workflow would be immensely helpful. Thank you. Charles