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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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1.7k
Apr ’25
DriverKit USB Transport to support multiple devices with different Vendor IDs
I have two different USB devices with different vendor IDs I would like to connect to. I submitted two separate requests for the com.apple.developer.driverkit.transport.usb entitlement for each vendor ID. However I am noticing the provisioning profile only has one of the vendor IDs. How do I submit a request for the USB Transport entitlement to support more than one vendor ID? I'm new to writing a DriverKit driver, so is this even possible?
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996
Dec ’24
Trouble using IOLog from a dext
Trying to use IOLog to print out a message from a dext. When I try to use IOLog, I get , though I did not or thought I did not tag it as private. I have tried to update the info.plist file for the dext according to https://developer.apple.com/forums/thread/705810, but that has not helped, or perhaps I am not defining it correctly since it's a dext. Anyone else had this issue, and how did you fix it?
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587
Feb ’25
Fails to capture IOUSBHostInterface with macOS 15.3 despite root privileges in app
I have an app that captures USB storage device and sends some commands to it. The app has a privilege helper tool which captures the USB device. Everything was working fine upto macOS 15.2 but it 15.3 update broke the functionality. When the helper tool tries to capture the USB device, it is able to capture IOUSBHostDevice but fails to capture IOUSBHostInterface. The error is Code: 3758097097; Domain: IOUSBHostErrorDomain; Description: Failed to create IOUSBHostInterface.; Reason: Failed [super init] I have verified the UID, EUID, GID, EGID = 0 for the helper process. So by IOUSBHost documentation it should have worked. The code that cause the error inside the helper tool is func captureUSBInterface(interface: io_service_t) -> IOUSBHostInterface? { let queue = DispatchQueue(label: "com.example.usbdevice.queue2") var capturedInterface: IOUSBHostInterface? do { capturedInterface = try IOUSBHostInterface(__ioService: interface, options: .deviceCapture, queue: queue, interestHandler: nil) } catch { NSLog("Failed to capture USB interface: \(error)") return nil } return capturedInterface } The app has sandbox=False and is distributed outside of the App Store. Please advise (long-term, short-term solutions) on how to make this work.
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490
Feb ’25
USB Accessory Device Charging Behavior Changed with iOS18
Hello, We are experiencing some issues with our USB accessory unexpectedly charging the iOS device it is connected with only when the iOS device supports USB-C and is on iOS 18+ The following is a description of the discrepancy we note between iOS versions: After performing a USB Role switch, our Accessory becomes a typical USB Device and the Apple device becomes the USB host. with iOS 17: 
 The Accessory then sends a PowerSourceUpdate message to the iOS 17 device via iAP2 protocol. Apple device has a USB Type C Connector. * We are specifying: AvailableCurrentForDevice = 0 mA  DeviceBatteryShouldChargeIfPowerIsPresent = 1. Three observations: iPad Battery Settings page -  we observe  'Last charged to…' (indicating no charging) On the Lumify App running (iOS 17), we observe that UIKit.current.batteryState indicated 'Not charging' Battery icon on top right of the screen indicates 'No Charging' with iOS 18: The same Accessory sends the same PowerSourceUpdate message to the iOS 18 device via iAP2 protocol using USB Type C Connector. We are specifying the same: AvailableCurrentForDevice = 0 mA DeviceBatteryShouldChargeIfPowerIsPresent = 1. We observe: iPad Battery Settings page -  we observe  'Charging'  On the Lumify App running (iOS 18), we observe that UIKit.current.batteryState indicated 'Charging' Battery icon on top right of the screen indicates 'No Charging' Please could you help us understand why the Battery status is showing as 'Charging' in the Settings page and with the 'UIKit.current.batteryState' even though we have specified 'AvailableCurrentForDevice = 0 mA'?
 Since our accessory is heavily reliant on the Battery status / Charging state, is there potentially another way we get an accurate battery charging status that we are missing? Or are there other suggestions outside of what we do currently to ensure our accessory does not place the iOS18 device into a charging state?
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459
May ’25
Cleaning up CoreAudio preferences
Hi, our virtual CoreAudio server plugin creates and removes dynamically CoreAudio devices. Each time it does so it leaves traces in /Library/Preferences/Audio com.apple.audio.DeviceSettings.plist com.apple.audio.SystemSettings.plist The files on the test machine now have become >1Mb and the system keeps recreating them. How can I manually remove/cleanup these files? (This is for development only. It already became pretty tedious to evaluate current device settings for debugging purposes.) How can the CoreAudio server plugin make sure once a device has been removed also its entries are removed from the .plist (It already removes it's storage, but the system still keeps other settings.) Is there some documentation about what gets stored and how the settings are organized in these preferences? (This is also for development and debugging only. We are not intending to access these settings directly ) Thanks!
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175
Apr ’25
bInterfaceNumber for multiple interface usb-cdcacm device
Hi, I have a usb composite device with multiple interfaces that support cdc-acm UARTs. My custom driver (.dext) loads and works for single channel usb-cdcccm device with these entries in the info.plist: bInterfaceNumber 1 But there is no option to define multiple "bInterfaceNumber" key. I tried bInterfaceClass also, as given below, but no success. Option-1: bInterfaceClass 10 bInterfaceSubClass 0 bInterfaceProtocol 0 Option-2: bInterfaceClass 10 bInterfaceSubClass 0 bInterfaceProtocol 0 Both the above options yield no result. But as I said in the beginning: <key>IOProviderClass</key> <string>IOUSBHostInterface</string> <key>IOClass</key> <string>IOUserSerial</string> <key>IOResourceMatch</key> <string>IOKit</string> <key>IOUserClass</key> <string>MyDriver</string> <key>IOUserServerName</key> <string>$(PRODUCT_BUNDLE_IDENTIFIER)</string> <key>idVendor</key> <integer>VENDORID</integer> <key>idProduct</key> <integer>PRODUCTID</integer> <key>bInterfaceNumber</key> <integer>1</integer> <key>bConfigurationValue</key> <integer>1</integer> "MyDriver" loads for interface-1 and works fine. The default AppleCDCACM driver loads for the 2nd channel. I want the same driver load for both the channels. Any help/suggestions \is very much appreciated. Thank you.
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141
Jul ’25
iPAD: achieve UserClient's privileges in background to have robust IOServiceAddMatchingNotification(...) as if ~[Background modes][Enable external communications].
1) The circumstances: iPADOS~>18, USB still-imaging-gadget, 1-3 gadgets might connect simultaneously via USB-hub, proprietary DExt, UserClient App in developers' iPADs or in TestFlight. = 1 variation A) UserClientApp has attribute [Background modes][Enable external communications]. = 1 variation B) "active USB-hub" vs "passive". = 1 variation C) "ConsoleApp logs iPAD" vs "ConsoleApp is not started". = 1 the term "zombie" below assume issue: == after plug-in ConsoleApp logs "IOUsbUserInterface::init", "::start"; == UserClient never receives respective callback from IOServiceAddMatchingNotification == further IOKit APIs "teardown", "restart" and "re-enumeration of connected gadgets" doesn't reveal the zombie (while it sees another simultaneous gadget); == unplug of the gadget logs "IOUsbUserInterface::stop". =2) The situation when UserClient is in foreground: ~ everything is fine. Note in MAC OS everything (same DExt and UserClient-code) works fine in background and in foreground. =3) The situation when UserClient is in background (beneath ~"Files" or "Safari"): =3A) "1A=true" phys plugin causes zombie in ~1/20 cases (satisfactory) =3B) "1A=false" phys plugin causes zombie in ~1/4 cases (non-satisfactory) =3C) "1 variation B" and "1 variation C" reduce zombies by ~>30%. =3D) ConsoleApp logs with filter "IOAccessory" (~about USB-energy) always look similar by my eyes. =4) From Apple-store: "The app declares support for external-accessory in the UIBackgroundModes"..."The external accessory background mode is intended for apps that communicate with hardware accessories through the External Accessory framework."..."Additionally, the app must be authorized by MFi," =5) My wish/ask: =5 option A) A clue to resolve the "zombie-plugin-issue in background" in a technical manner. = E.g. find a straightforward solution that ~elevates UserClient's "privileges" in background like [Enable external communication]... E.g. what ConsoleApp-logs to add/watch to reveal my potential bugs in DExt or in UserClient? =5 option B) A way to pursue Apple-store to accept (without MFI) an UserClientApp with [Enable external communication].
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291
Oct ’25
Custom USB Network Device Driver on iPhone
Hi, We are using the AX88772C as a USB->Ethernet bridge in a product we are developing. Due to the chip not following the NCM protocol, it is not supported by the default networking drivers on the iPhone. Initially, we intended on using DriverKit to develop a userspace driver for this device. However, we have been informed DriverKit is only available on iPad OS, not iOS. As such is the case, we have found two possible alternatives. First being IOkit, and the second being External Accessory Session (EASession). What are the limitations of each of these options? We need the ability to send and receive USB packets to Control and Bulk endpoints. Is this possible with either of the options defined above? Would either of these options require the device to be MFi certified? We have read that some APIs within IOkit require the apple device to be jailbroken. Is there a list of features that can be used without a jailbroken device? Documentation on these 2 options is limited, so any official documentation would be great. Thanks!
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177
Oct ’25
DEXT receives zero-filled buffer from DMA, despite firmware confirming data write
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
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197
Oct ’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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1k
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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2d
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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168
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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182
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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IOServiceOpen fails with -308 Error (smUnExBusError)
I have a driver project where I'm opening and closing a connection to a custom driver. If I do what I think I need to be doing to unmap the memory, when I try to open the service again, it fails. If I skip the step where I do that unmapping, the service opens successfully. If I call unmap() before trying to call openConnection() again, it will fail with a -308 error return code. If I skip that call to unmap(), it works and I'm able to communicate with my device. Here's the code where I open the service: public func openConnection() throws { guard !isOpen else { return } // Open device var connection: io_connect_t = IO_OBJECT_NULL var result = IOServiceOpen(device, mach_task_self_, 0, &connection) if result != kIOReturnSuccess { NSLog("Failed opening device with error: 0x%08x.\n", result); throw NSError.cdc_kernelReturnErrorWithError(result) } defer { IOConnectRelease(connection) } if device == IO_OBJECT_NULL || connection == IO_OBJECT_NULL { throw NSError.cdc_kernelReturnErrorWithError(result) } let receiveDataMappedMemory = ClientDriverMappedMemory(connection: connection, memoryType: MappedMemoryType_ReceiveDataBuffer) try receiveDataMappedMemory.map() let transmitDataMappedMemory = ClientDriverMappedMemory(connection: connection, memoryType: MappedMemoryType_TransmitDataBuffer) try transmitDataMappedMemory.map() // Setup async notification IONotificationPortSetDispatchQueue(dataReceivedPort, dataReceivedQueue) let callbackPort = IONotificationPortGetMachPort(dataReceivedPort) let input = DataStruct(foo: 0, bar: 0) var output = DataStruct(foo: 0, bar: 0) var outputSize = MemoryLayout<DataStruct>.size // Trampoline to C function because I don't quite know how to make this work in Swift result = setupCallback(self, connection, callbackPort, input, &output, &outputSize) if result != kIOReturnSuccess { NSLog("Error registering async callback with driver: \(result)"); throw NSError.cdc_kernelReturnErrorWithError(result) } self.connection = connection self.receivedDataMappedMemory = receiveDataMappedMemory self.transmitDataMappedMemory = transmitDataMappedMemory } map() and unmap() functions: - (BOOL)mapWithError:(NSError **)error { error = error ?: &(NSError * __autoreleasing){ nil }; kern_return_t result = IOConnectMapMemory64(self.connection, self.memoryType, mach_task_self(), &_address, &_size, kIOMapAnywhere); if (result != kIOReturnSuccess) { *error = [NSError cdc_kernelReturnErrorWithError:result]; return NO; } self.mapped = YES; return YES; } - (BOOL)unmapWithError:(NSError **)error { error = error ?: &(NSError * __autoreleasing){ nil }; kern_return_t result = IOConnectUnmapMemory64(self.connection, self.memoryType, mach_task_self(), _address); if (result != kIOReturnSuccess) { *error = [NSError cdc_kernelReturnErrorWithError:result]; return NO; } self.mapped = NO; return YES; } Any insights? What all should I be doing to close the service? Why would the unmapping create this issue or what else could the -308 error be indicated has gone wrong?
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669
Dec ’24
The curious case of the "IOKit Driver" Xcode target.
Firstly, I realise that Kexts are deprecated. And for my needs, user-space IOKit from an application might be more than I’ll ever need, but I can’t help ensuring I’ve got all my ducks in a row while I’m designing an app. I noticed in the above Kext deprecation notice that it’s more about specific APIs that are deprecated rather than the kext mechanism itself (no mention of IOKit kernel APIs there). Along with the fact that a reboot would be required and various other policy changes. While reading up on System Extensions and the various newer tools, DriverKit, Endpoint Security etc, I’ve noticed there’s no mention of this “IOKit Driver” target/deliverable in the Xcode template chooser. It looks like, from the requirements, that DriverKit is aimed at hardware manufacturers, with a need to request the DriverKit entitlement for development. With respect to Apple’s internal Kext deprecation roadmap, how safe is it to build a product that relies on using an IOKit Driver and are there any requirements similar to DriverKit? Would a developer need to request an entitlement? If I developed an app using user-space IOKit and, for illustration purposes let’s say I also included an IOKit Driver in the app bundle. If I used the IOKit API, including header file constants only (no digging around in the IORegistryExplorer for non-public keys), as Apple intends them to be used, would this fall foul of any App Store rules that anyone is aware of? Put another way, would making use of an IOKit Driver disqualify my app from being distributed via the App Store, similar to an Endpoint Security extension? As an aside, there are a lot of API in the ES Framework that could be used to build apps that have nothing to do with Endpoint Security. File system related apps for example. It’s a shame there isn’t an enhanced middle ground between FSEvents and Endpoint Security framework.
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827
Dec ’24
Issue Writing to BAR1 After BAR0 is Unavailable
Hello Everyone, I encountered an issue with PCI memory access in DriverKit. In my case, BAR0 is not available, but BAR1 is ready for use. Here’s the log output: !!! ERROR : Failed to get BAR0 info (error: 0xe00002f0). !!! BAR1 - MemoryIndex: 0x00000000, Size: 0x00040000, Type: 0 Issue Description When I initially wrote to BAR0 using memoryIndex = 0, it worked successfully: AME_Address_Write_32(pAMEData, pAMEData->memoryIndex, AME_HOST_INT_MASK_REGISTER, 0x0F); However, I mistakenly forgot to update memoryIndex to 1 for BAR1. Surprisingly, the write operation still succeeded. When I fixed memoryIndex = 1 for BAR1, the write operation no longer had any effect. There was no error, but the expected behavior did not occur. Relevant API (From IOPCIDevice.iig) /*! /*! * @brief Writes a 32-bit value to the PCI device's aperture at a given memory index. * @discussion This method writes a 32-bit register on the device and returns its value. * @param memoryIndex An index into the array of ranges assigned to the device. * @param offset An offset into the device's memory specified by the index. * @param data A 32-bit value to be written in host byte order. */ void MemoryWrite32(uint8_t memoryIndex, uint64_t offset, uint32_t data) LOCALONLY; Log Output: Writes to BAR0 (memoryIndex = 0) AME_Address_Write_32() called memoryIndex: 0, offset: 0x34, data: 0xf Wrote data 0xF to offset 52 AME_Address_Write_32() called memoryIndex: 0, offset: 0xa0, data: 0x1 Wrote data 0x1 to offset 160 AME_Address_Write_32() called memoryIndex: 0, offset: 0x20, data: 0xffffffff Wrote data 0xFFFFFFFF to offset 32 Writes to BAR1 (memoryIndex = 1) – No Response AME_Address_Write_32() called memoryIndex: 1, offset: 0x34, data: 0xf No confirmation log, no visible effect. Questions What should memoryIndex be set to for BAR1? The log shows "BAR1 - MemoryIndex: 0x00000000", but should I be using 1 instead? How can I verify if a write operation to BAR1 is successful? Is there a way to check if the memory region is actually writable? Should I use MemoryRead32() to confirm the written value? Any guidance would be greatly appreciated! Best Regards, Charles
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92
Mar ’25
Implementing Hardware Interrupt Handling with InterruptOccurred in DriverKit
Hello everyone, I’m working on implementing hardware interrupt handling in DriverKit and came across the InterruptOccurred method in IOInterruptDispatchSource. I noticed that its declaration ends with a TYPE macro: virtual void InterruptOccurred(OSAction* action, uint64_t count, uint64_t time) TYPE(IOInterruptDispatchSource::InterruptOccurred); This structure seems similar to how Timer Events are set up, where an event is linked to a callback and triggered by a timer. I’m attempting to use a similar approach, but for hardware-triggered interrupts rather than timer events. I’m currently in the trial-and-error phase of the implementation, but if anyone has a working example or reference on how to properly implement and register InterruptOccurred, it would be greatly appreciated! Best regards, Charles
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241
May ’25
Issues accessing UserDefaults and performing API calls in CarPlay while iPhone is locked
I'm developing a CarPlay Fueling app with CarPlay entitlement properly configured. While testing, I ran into two issues and would appreciate any guidance: UserDefaults access while iPhone is locked: In my CarPlay implementation, I read values from UserDefaults that were previously saved in the iOS app. However, when the iPhone is locked and the CarPlay session is active, it seems that the CarPlay extension cannot read the stored values. Is this the expected behavior? If so, how can I persist and access data across the app and CarPlay reliably? API calls while iPhone is locked: The CarPlay interface in my app communicates with a server to display lists and detail views. When the iPhone is locked, are network calls still allowed from the CarPlay extension? Currently, I do not have any background modes enabled in the app capabilities. If I enable background modes and implement background network logic to ensure API calls complete properly, would this be considered acceptable usage for CarPlay in App Store review? Or could it raise any rejection concerns during the approval process? Thanks in advance for your help.
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94
Jun ’25