Bump manifest-merger from 30.0.4 to 30.1.0 in /src/manifestmerger #4
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Bumps manifest-merger from 30.0.4 to 30.1.0. --- updated-dependencies: - dependency-name: com.android.tools.build:manifest-merger dependency-type: direct:production update-type: version-update:semver-minor ... Signed-off-by: dependabot[bot] <[email protected]>
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…6672) Context: dotnet/maui#4262 Context: dotnet#6675 If you run the `maui-blazor` template in a Release build: dotnet build -t:Run -c Release it crashes at runtime: D monodroid-assembly: typemap: type with token 33555274 (0x200034a) in module {C7B4CC8F-7A03-4A3F-A34A-DC66EDC548B9} (Mono.Android) corresponds to Java type 'android/runtime/JavaProxyThrowable' … F DEBUG : backtrace: F DEBUG : #00 pc 000000000065d8fc /apex/com.android.art/lib64/libart.so (void art::StackVisitor::WalkStack<(art::StackVisitor::CountTransitions)0>(bool)+156) (BuildId: 7fbaf2a1a3317bd634b00eb90e32291e) F DEBUG : #1 pc 000000000069b25d /apex/com.android.art/lib64/libart.so (art::Thread::GetCurrentMethod(unsigned int*, bool, bool) const+157) (BuildId: 7fbaf2a1a3317bd634b00eb90e32291e) F DEBUG : #2 pc 0000000000430fed /apex/com.android.art/lib64/libart.so (art::JNI<false>::FindClass(_JNIEnv*, char const*)+765) (BuildId: 7fbaf2a1a3317bd634b00eb90e32291e) F DEBUG : #3 pc 0000000000047e5a /data/app/~~0Qm6D1S0sO3f1lwfakN0PA==/com.companyname.mauiapp2-08UokVCH5k_PlbZEH_hhkA==/split_config.x86_64.apk!libmono-android.release.so (offset 0x11e000) (java_interop_jnienv_find_class+26) (BuildId: 3d04f8b946590175e97b89aee2e3b19ceed4b524) F DEBUG : #4 pc 00000000000128ac <anonymous:41640000> The crash can be avoided by disabling the linker: dotnet build -t:Run -c Release -p:AndroidLinkMode=None # -or- dotnet build -t:Run -c Release -p:PublishTrimmed=false However, let us return to the crash: *why* is it crashing? This isn't a "good debugging experience"; we have no useful context. Lots of investigation later -- all hail printf debugging -- and we found that the cause of the crash was an unhandled exception: 1. `Mono.Android.dll` has it's Java Callable Wrappers generated from the *unlinked* assembly, into `mono.android.jar` and `mono.android.dex` files. The Java Callable Wrapper for `Android.Runtime.InputStreamAdapter` thus includes *all* `Read()` method overloads. 2. When the app is built in Release configuration, linking is enabled, and *some* of the `InputStreamAdapter.Read()` methods are removed by the linker, along with the `Java.IO.InputStream.Read()` methods that were overridden. 3. At runtime, we perform [Java Type Registration][0] for the `Android.Runtime.InputStreamAdapter` type, which eventually calls `AndroidTypeManager.RegisterNativeMembers()`, which eventually attempts to *effectively* do: Delegate.CreateDelegate ( typeof(Func<Delegate>), typeof(InputStreamAdapter), "GetReadHandler"); 4. Because of (2), `Java.IO.InputStream.GetReadHandler()` *does not exist*, and thus `Delegate.CreateDelegate()` throws an `ArgumentException`. So far, so reasonable, but… 5. `AndroidTypeManager.RegisterNativeMembers()` didn't catch any exceptions, nor did any other method between the original Java `Runtime.register()` invocation and `AndroidTypeManager.RegisterNativeMembers()`. The result is that a C# exception was "in flight", and Mono then proceeded to *tear down the stack frame* as it unwound the callstack looking for `catch` handlers. At this point, the process is toast: the runtime stack is FUBAR. This is also why the `backtrace:` is "rooted" in `JNIEnv::FindClass()`: `JNIEnv::FindClass()` invokes Java static constructors before returning, which is how the static constructor in the Java Callable Wrapper for `InputStreamAdapter` called `Runtime.register()` in the first place. All of this makes for a miserable debugging experience. Fixing the "original" linker issue will be done in dotnet#6675. This hasn't been an issue in "Classic" Xamarin.Android, presumably because the classic linker isn't as good as the net6 linker. What we want to do *here* is improve this debugging experience, by "wrapping" `AndroidTypeManager.RegisterNativeMembers()` in a `try`/`catch` block, which can then *marshal the thrown exception* back to Java. This *prevents* Mono from unwinding the callstack past a JNI boundary, and avoids the annoying-to-debug app crash. After this change, we get a much friendlier unhandled exception crash: I MonoDroid: Android.Runtime.JavaProxyThrowable: Exception_WasThrown, Android.Runtime.JavaProxyThrowable I MonoDroid: I MonoDroid: --- End of managed Android.Runtime.JavaProxyThrowable stack trace --- I MonoDroid: android.runtime.JavaProxyThrowable: System.ArgumentException: Arg_DlgtTargMeth I MonoDroid: at System.Delegate.CreateDelegate(Type , Type , String , Boolean , Boolean ) I MonoDroid: at System.Delegate.CreateDelegate(Type , Type , String ) I MonoDroid: at Android.Runtime.AndroidTypeManager.RegisterNativeMembers(JniType , Type , String ) I MonoDroid: --- End of stack trace from previous location --- I MonoDroid: at Java.Interop.JniEnvironment.StaticMethods.CallStaticObjectMethod(JniObjectReference , JniMethodInfo , JniArgumentValue* ) I MonoDroid: at Android.Runtime.JNIEnv.CallStaticObjectMethod(IntPtr , IntPtr , JValue* ) I MonoDroid: at Android.Runtime.JNIEnv.CallStaticObjectMethod(IntPtr , IntPtr , JValue[] ) I MonoDroid: at Android.Runtime.JNIEnv.FindClass(String ) I MonoDroid: at Android.Runtime.JNIEnv.AllocObject(String ) I MonoDroid: at Android.Runtime.JNIEnv.StartCreateInstance(String , String , JValue* ) I MonoDroid: at Android.Runtime.JNIEnv.StartCreateInstance(String , String , JValue[] ) I MonoDroid: at Android.Runtime.InputStreamAdapter..ctor(Stream ) I MonoDroid: at Android.Runtime.InputStreamAdapter.ToLocalJniHandle(Stream ) I MonoDroid: at Android.Webkit.WebResourceResponse..ctor(String , String , Int32 , String , IDictionary`2 , Stream ) I MonoDroid: at Microsoft.AspNetCore.Components.WebView.Maui.WebKitWebViewClient.ShouldInterceptRequest(WebView view, IWebResourceRequest request) I MonoDroid: at Android.Webkit.WebViewClient.n_ShouldInterceptRequest_Landroid_webkit_WebView_Landroid_webkit_WebResourceRequest_(IntPtr , IntPtr , IntPtr , IntPtr ) I MonoDroid: at crc64d693e2d9159537db.WebKitWebViewClient.n_shouldInterceptRequest(Native Method) I MonoDroid: at crc64d693e2d9159537db.WebKitWebViewClient.shouldInterceptRequest(WebKitWebViewClient.java:39) I MonoDroid: at Rr.a(chromium-TrichromeWebViewGoogle.apk-stable-410410686:16) I MonoDroid: at org.chromium.android_webview.AwContentsBackgroundThreadClient.shouldInterceptRequestFromNative(chromium-TrichromeWebViewGoogle.apk-stable-410410686:2) I MonoDroid: I MonoDroid: --- End of managed Android.Runtime.JavaProxyThrowable stack trace --- I MonoDroid: android.runtime.JavaProxyThrowable: System.ArgumentException: Arg_DlgtTargMeth I MonoDroid: at System.Delegate.CreateDelegate(Type , Type , String , Boolean , Boolean ) I MonoDroid: at System.Delegate.CreateDelegate(Type , Type , String ) I MonoDroid: at Android.Runtime.AndroidTypeManager.RegisterNativeMembers(JniType , Type , String ) I MonoDroid: --- End of stack trace from previous location --- I MonoDroid: at Java.Interop.JniEnvironment.StaticMethods.CallStaticObjectMethod(JniObjectReference , JniMethodInfo , JniArgumentValue* ) I MonoDroid: at Android.Runtime.JNIEnv.CallStaticObjectMethod(IntPtr , IntPtr , JValue* ) I MonoDroid: at Android.Runtime.JNIEnv.CallStaticObjectMethod(IntPtr , IntPtr , JValue[] ) I MonoDroid: at Android.Runtime.JNIEnv.FindClass(String ) I MonoDroid: at Android.Runtime.JNIEnv.AllocObject(String ) I MonoDroid: at Android.Runtime.JNIEnv.StartCreateInstance(String , String , JValue* ) I MonoDroid: at Android.Runtime.JNIEnv.StartCreateInstance(String , String , JValue[] ) I MonoDroid: at Android.Runtime.InputStreamAdapter..ctor(Stream ) I MonoDroid: at Android.Runtime.InputStreamAdapter.ToLocalJniHandle(Stream ) I MonoDroid: at Android.Webkit.WebResourceResponse..ctor(String , String , Int32 , String , IDictionary`2 , Stream ) I MonoDroid: at Microsoft.AspNetCore.Components.WebView.Maui.WebKitWebViewClient.ShouldInterceptRequest(WebView view, IWebResourceRequest request) I MonoDroid: at Android.Webkit.WebViewClient.n_ShouldInterceptRequest_Landroid_webkit_WebView_Landroid_webkit_WebResourceRequest_(IntPtr , IntPtr , IntPtr , IntPtr ) I MonoDroid: at crc64d693e2d9159537db.WebKitWebViewClient.n_shouldInterceptRequest(Native Method) I MonoDroid: at crc64d693e2d9159537db.WebKitWebViewClient.shouldInterceptRequest(WebKitWebViewClient.java:39) I MonoDroid: at Rr.a(chromium-TrichromeWebViewGoogle.apk-stable-410410686:16) I MonoDroid: at org.chromium.android_webview.AwContentsBackgroundThreadClient.shouldInterceptRequestFromNative(chromium-TrichromeWebViewGoogle.apk-stable-410410686:2) This is much easier to reason about, and will save us time in the future. [0]: https://github.com/xamarin/xamarin-android/wiki/Blueprint#java-type-registration
|
Superseded by #5. |
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…otnet#7732) Fixes: dotnet#7335 Context: d236af5 Commit d236af5 introduced embedded assembly compression, using LZ4, which speeds up startup and reduces final package size. Assemblies are compressed at build time and, at the same time, pre- allocated buffers for the **decompressed** data are allocated in `libxamarin-app.so`. The buffers are then passed to the LZ4 APIs, all threads using the same output buffer. The assumption was that we can do fine without locking as even if overlapped decompression happens, the output data will be the same and so even if two threads do the same thing at the same time, the data will be valid at all times, so long as at least one thread completes the decompression. This assumption proved to be **largely** true, but it appears that in high concurrency cases it is possible that the data in the decompression buffer differs. This can result in app crashes: A/libc: Fatal signal 6 (SIGABRT), code -1 (SI_QUEUE) in tid 3092 (.NET ThreadPool), pid 2727 (myapp.name) A/DEBUG: pid: 2727, tid: 3092, name: .NET ThreadPool >>> myapp.name <<< A/DEBUG: #1 pc 0000000000029b1c /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmono-android.release.so (offset 0x103d000) (xamarin::android::internal::MonodroidRuntime::mono_log_handler(char const*, char const*, char const*, int, void*)+144) (BuildId: 29c5a3805a0bedee1eede9b6668d7c676aa63371) A/DEBUG: #2 pc 00000000002680bc /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (offset 0x109b000) (BuildId: 4a5dd4396e8816b7f69881838bd549285213d53b) A/DEBUG: #3 pc 00000000002681e8 /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (offset 0x109b000) (BuildId: 4a5dd4396e8816b7f69881838bd549285213d53b) A/DEBUG: #4 pc 000000000008555c /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (offset 0x109b000) (mono_metadata_string_heap+188) (BuildId: 4a5dd4396e8816b7f69881838bd549285213d53b) … My guess is that LZ4 either uses the output buffer as a scratchpad area when decompressing or that it initializes/modifies the buffer before writing actual data in it. With overlapped decompression, it may lead to one thread overwriting valid data previously written by another thread, so that when the latter returns the buffer it thought to have had valid data may contain certain bytes temporarily overwritten by the decompression session in the other, still running, thread. It may happen that MonoVM reads the corrupted data just when it is still invalid (before the still running decompression session actually writes the valid data), a classic race condition. To fix this, the decompression block is now protected with a startup- aware mutex. Mutex will be held only after the initial startup phase is completed, so there should not be much loss of startup performance.
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Feb 27, 2023
…otnet#7817) Fixes: dotnet#7335 Context: d236af5 Commit d236af5 introduced embedded assembly compression, using LZ4, which speeds up startup and reduces final package size. Assemblies are compressed at build time and, at the same time, pre- allocated buffers for the **decompressed** data are allocated in `libxamarin-app.so`. The buffers are then passed to the LZ4 APIs, all threads using the same output buffer. The assumption was that we can do fine without locking as even if overlapped decompression happens, the output data will be the same and so even if two threads do the same thing at the same time, the data will be valid at all times, so long as at least one thread completes the decompression. This assumption proved to be **largely** true, but it appears that in high concurrency cases it is possible that the data in the decompression buffer differs. This can result in app crashes: A/libc: Fatal signal 6 (SIGABRT), code -1 (SI_QUEUE) in tid 3092 (.NET ThreadPool), pid 2727 (myapp.name) A/DEBUG: pid: 2727, tid: 3092, name: .NET ThreadPool >>> myapp.name <<< A/DEBUG: #1 pc 0000000000029b1c /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmono-android.release.so (offset 0x103d000) (xamarin::android::internal::MonodroidRuntime::mono_log_handler(char const*, char const*, char const*, int, void*)+144) (BuildId: 29c5a3805a0bedee1eede9b6668d7c676aa63371) A/DEBUG: #2 pc 00000000002680bc /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (offset 0x109b000) (BuildId: 4a5dd4396e8816b7f69881838bd549285213d53b) A/DEBUG: #3 pc 00000000002681e8 /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (offset 0x109b000) (BuildId: 4a5dd4396e8816b7f69881838bd549285213d53b) A/DEBUG: #4 pc 000000000008555c /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (offset 0x109b000) (mono_metadata_string_heap+188) (BuildId: 4a5dd4396e8816b7f69881838bd549285213d53b) … My guess is that LZ4 either uses the output buffer as a scratchpad area when decompressing or that it initializes/modifies the buffer before writing actual data in it. With overlapped decompression, it may lead to one thread overwriting valid data previously written by another thread, so that when the latter returns the buffer it thought to have had valid data may contain certain bytes temporarily overwritten by the decompression session in the other, still running, thread. It may happen that MonoVM reads the corrupted data just when it is still invalid (before the still running decompression session actually writes the valid data), a classic race condition. To fix this, the decompression block is now protected with a startup- aware mutex. Mutex will be held only after the initial startup phase is completed, so there should not be much loss of startup performance.
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Jul 17, 2023
) Context: 929e701 Context: ce2bc68 Context: dotnet#7473 Context: dotnet#8155 The managed linker can produce assemblies optimized for the target `$(RuntimeIdentifier)` (RID), which means that they will differ between different RIDs. Our "favorite" example of this is `IntPtr.Size`, which is inlined by the linker into `4` or `8` when targeting 32-bit or 64-bit platforms. (See also dotnet#7473 and 929e701.) Another platform difference may come in the shape of CPU intrinsics which will change the JIT-generated native code in ways that will crash the application if the assembler instructions generated for the intrinsics aren't supported by the underlying processor. In addition, the per-RID assemblies will have different [MVID][0]s and **may** have different type and method metadata token IDs, which is important because typemaps *use* type and metadata token IDs; see also ce2bc68. All of this taken together invalidates our previous assumption that all the managed assemblies are identical. "Simply" using `IntPtr.Size` in an assembly that contains `Java.Lang.Object` subclasses will break things. This in turn could cause "mysterious" behavior or crashes in Release applications; see also Issue dotnet#8155. Prevent the potential problems by processing each per-RID assembly separately and output correct per-RID LLVM IR assembly using the appropriate per-RID information. Additionally, during testing I found that for our use of Cecil within `<GenerateJavaStubs/>` doesn't consistently remove the fields, delegates, and methods we remove in `MarshalMethodsAssemblyRewriter` when marshal methods are enabled, or it generates subtly broken assemblies which cause **some** applications to segfault at run time like so: I monodroid-gc: 1 outstanding GREFs. Performing a full GC! F libc : Fatal signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 0x8 in tid 12379 (t6.helloandroid), pid 12379 (t6.helloandroid) F DEBUG : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** F DEBUG : Build fingerprint: 'google/raven_beta/raven:14/UPB3.230519.014/10284690:user/release-keys' F DEBUG : Revision: 'MP1.0' F DEBUG : ABI: 'arm64' F DEBUG : Timestamp: 2023-07-04 22:09:58.762982002+0200 F DEBUG : Process uptime: 1s F DEBUG : Cmdline: com.microsoft.net6.helloandroid F DEBUG : pid: 12379, tid: 12379, name: t6.helloandroid >>> com.microsoft.net6.helloandroid <<< F DEBUG : uid: 10288 F DEBUG : tagged_addr_ctrl: 0000000000000001 (PR_TAGGED_ADDR_ENABLE) F DEBUG : signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 0x0000000000000008 F DEBUG : Cause: null pointer dereference F DEBUG : x0 0000000000000000 x1 0000007ba1401af0 x2 00000000000000fa x3 0000000000000001 F DEBUG : x4 0000007ba1401b38 x5 0000007b9f2a8360 x6 0000000000000000 x7 0000000000000000 F DEBUG : x8 ffffffffffc00000 x9 0000007b9f800000 x10 0000000000000000 x11 0000007ba1400000 F DEBUG : x12 0000000000000000 x13 0000007ba374ad58 x14 0000000000000000 x15 00000013ead77d66 F DEBUG : x16 0000007ba372f210 x17 0000007ebdaa4a80 x18 0000007edf612000 x19 000000000000001f F DEBUG : x20 0000000000000000 x21 0000007b9f2a8320 x22 0000007b9fb02000 x23 0000000000000018 F DEBUG : x24 0000007ba374ad08 x25 0000000000000004 x26 0000007b9f2a4618 x27 0000000000000000 F DEBUG : x28 ffffffffffffffff x29 0000007fc592a780 F DEBUG : lr 0000007ba3701f44 sp 0000007fc592a730 pc 0000007ba3701e0c pst 0000000080001000 F DEBUG : 8 total frames F DEBUG : backtrace: F DEBUG : #00 pc 00000000002d4e0c /data/app/~~Av24J15xbf20XdrY3X2_wA==/com.microsoft.net6.helloandroid-4DusuNWIAkz1Ssi7fWVF-g==/lib/arm64/libmonosgen-2.0.so (BuildId: 761134f2369377582cc3a8e25ecccb43a2e0a877) F DEBUG : #1 pc 00000000002c29e8 /data/app/~~Av24J15xbf20XdrY3X2_wA==/com.microsoft.net6.helloandroid-4DusuNWIAkz1Ssi7fWVF-g==/lib/arm64/libmonosgen-2.0.so (BuildId: 761134f2369377582cc3a8e25ecccb43a2e0a877) F DEBUG : #2 pc 00000000002c34bc /data/app/~~Av24J15xbf20XdrY3X2_wA==/com.microsoft.net6.helloandroid-4DusuNWIAkz1Ssi7fWVF-g==/lib/arm64/libmonosgen-2.0.so (BuildId: 761134f2369377582cc3a8e25ecccb43a2e0a877) F DEBUG : #3 pc 00000000002c2254 /data/app/~~Av24J15xbf20XdrY3X2_wA==/com.microsoft.net6.helloandroid-4DusuNWIAkz1Ssi7fWVF-g==/lib/arm64/libmonosgen-2.0.so (BuildId: 761134f2369377582cc3a8e25ecccb43a2e0a877) F DEBUG : #4 pc 00000000002be0bc /data/app/~~Av24J15xbf20XdrY3X2_wA==/com.microsoft.net6.helloandroid-4DusuNWIAkz1Ssi7fWVF-g==/lib/arm64/libmonosgen-2.0.so (BuildId: 761134f2369377582cc3a8e25ecccb43a2e0a877) F DEBUG : #5 pc 00000000002bf050 /data/app/~~Av24J15xbf20XdrY3X2_wA==/com.microsoft.net6.helloandroid-4DusuNWIAkz1Ssi7fWVF-g==/lib/arm64/libmonosgen-2.0.so (BuildId: 761134f2369377582cc3a8e25ecccb43a2e0a877) F DEBUG : #6 pc 00000000002a53a4 /data/app/~~Av24J15xbf20XdrY3X2_wA==/com.microsoft.net6.helloandroid-4DusuNWIAkz1Ssi7fWVF-g==/lib/arm64/libmonosgen-2.0.so (mono_gc_collect+44) (BuildId: 761134f2369377582cc3a8e25ecccb43a2e0a877) F DEBUG : #7 pc 000000000000513c <anonymous:7ec716b000> This is because we generate Java Callable Wrappers over a set of original (linked or not) assemblies, then we scan them for classes derived from `Java.Lang.Object` and use that set as input to the marshal methods rewriter, which makes the changes (generates wrapper methods, decorates wrapped methods with `[UnmanagedCallersOnly]`, removes the old delegate methods as well as delegate backing fields) to all the `Java.Lang.Object` subclasses, then writes the modified assembly to a `new/<assembly.dll>` location (efa14e2), followed by copying the newly written assemblies back to the original location. At this point, we have the results returned by the subclass scanner in memory and **new** versions of those types on disk, but they are out of sync, since the types in memory refer to the **old** assemblies, but AOT is ran on the **new** assemblies which have a different layout, changed MVIDs and, potentially, different type and method token IDs (because we added some methods, removed others etc) and thus it causes the crashes at the run time. The now invalid set of "old" types is passed to the typemap generator. This only worked by accident, because we (incorrectly) used only the first linked assembly which happened to be the same one passed to the JLO scanner and AOT - so everything was fine at the execution time. Address this by *disabling* LLVM Marshal Methods (8bc7a3e) for .NET 8, setting `$(AndroidEnableMarshalMethods)`=False by default. We'll attempt to fix these issues for .NET 9. [0]: https://learn.microsoft.com/dotnet/api/system.reflection.module.moduleversionid?view=net-7.0
jonathanpeppers
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Aug 30, 2023
…otnet#7732) Fixes: dotnet#7335 Context: d236af5 Commit d236af5 introduced embedded assembly compression, using LZ4, which speeds up startup and reduces final package size. Assemblies are compressed at build time and, at the same time, pre- allocated buffers for the **decompressed** data are allocated in `libxamarin-app.so`. The buffers are then passed to the LZ4 APIs, all threads using the same output buffer. The assumption was that we can do fine without locking as even if overlapped decompression happens, the output data will be the same and so even if two threads do the same thing at the same time, the data will be valid at all times, so long as at least one thread completes the decompression. This assumption proved to be **largely** true, but it appears that in high concurrency cases it is possible that the data in the decompression buffer differs. This can result in app crashes: A/libc: Fatal signal 6 (SIGABRT), code -1 (SI_QUEUE) in tid 3092 (.NET ThreadPool), pid 2727 (myapp.name) A/DEBUG: pid: 2727, tid: 3092, name: .NET ThreadPool >>> myapp.name <<< A/DEBUG: #1 pc 0000000000029b1c /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmono-android.release.so (offset 0x103d000) (xamarin::android::internal::MonodroidRuntime::mono_log_handler(char const*, char const*, char const*, int, void*)+144) (BuildId: 29c5a3805a0bedee1eede9b6668d7c676aa63371) A/DEBUG: #2 pc 00000000002680bc /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (offset 0x109b000) (BuildId: 4a5dd4396e8816b7f69881838bd549285213d53b) A/DEBUG: #3 pc 00000000002681e8 /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (offset 0x109b000) (BuildId: 4a5dd4396e8816b7f69881838bd549285213d53b) A/DEBUG: #4 pc 000000000008555c /data/app/myapp.name-B9t_3dF9i8mDxJEKodZw5w==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (offset 0x109b000) (mono_metadata_string_heap+188) (BuildId: 4a5dd4396e8816b7f69881838bd549285213d53b) … My guess is that LZ4 either uses the output buffer as a scratchpad area when decompressing or that it initializes/modifies the buffer before writing actual data in it. With overlapped decompression, it may lead to one thread overwriting valid data previously written by another thread, so that when the latter returns the buffer it thought to have had valid data may contain certain bytes temporarily overwritten by the decompression session in the other, still running, thread. It may happen that MonoVM reads the corrupted data just when it is still invalid (before the still running decompression session actually writes the valid data), a classic race condition. To fix this, the decompression block is now protected with a startup- aware mutex. Mutex will be held only after the initial startup phase is completed, so there should not be much loss of startup performance.
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Bumps manifest-merger from 30.0.4 to 30.1.0.
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@dependabot rebasewill rebase this PR@dependabot recreatewill recreate this PR, overwriting any edits that have been made to it@dependabot mergewill merge this PR after your CI passes on it@dependabot squash and mergewill squash and merge this PR after your CI passes on it@dependabot cancel mergewill cancel a previously requested merge and block automerging@dependabot reopenwill reopen this PR if it is closed@dependabot closewill close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually@dependabot ignore this major versionwill close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)@dependabot ignore this minor versionwill close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)@dependabot ignore this dependencywill close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)