Frequent crashes after migrating from Xamarin to .Net in libmonosgen2.0.so

[SejalH96]

Description

split_config.arm64_v8a.apk!libmonosgen-2.0.so

Reproduction Steps

Random Behaviour and it is observed in release build frequently as many issues reported in play console
Observed after migrating xamarin native application to .Net for Android

Expected behavior

Behaviour of application should remain same as it is before migration

Actual behavior

2k+ crash event reported in play console affecting 200+ users

Regression?

Observed after migrating xamarin native application to .Net for Android
Current used version: 9.0.7
Xamarin project does not have this issues.

Known Workarounds

No response

Configuration

No response

Other information

Here is one of the stacktrace which is reported in play console:

---

pid: 0, tid: 2174 >>> com.matrix.satatyamv <<<

backtrace:
#00 pc 0x00000000002b1f50 /data/app/~~HmJZrNwUrs1orXn9gkzwoA==/com.matrix.satatyamv-N6vjM8z_IkRTCQPSJZS_dQ==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (BuildId: eb2c97c83bb501fba52a668d79d86d30102202c4)
#1 pc 0x00000000002b3060 /data/app/~~HmJZrNwUrs1orXn9gkzwoA==/com.matrix.satatyamv-N6vjM8z_IkRTCQPSJZS_dQ==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (BuildId: eb2c97c83bb501fba52a668d79d86d30102202c4)
#2 pc 0x00000000002b446c /data/app/~~HmJZrNwUrs1orXn9gkzwoA==/com.matrix.satatyamv-N6vjM8z_IkRTCQPSJZS_dQ==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (BuildId: eb2c97c83bb501fba52a668d79d86d30102202c4)
#3 pc 0x00000000002b4f8c /data/app/~~HmJZrNwUrs1orXn9gkzwoA==/com.matrix.satatyamv-N6vjM8z_IkRTCQPSJZS_dQ==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (BuildId: eb2c97c83bb501fba52a668d79d86d30102202c4)
#4 pc 0x00000000002b2c4c /data/app/~~HmJZrNwUrs1orXn9gkzwoA==/com.matrix.satatyamv-N6vjM8z_IkRTCQPSJZS_dQ==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (BuildId: eb2c97c83bb501fba52a668d79d86d30102202c4)
#5 pc 0x00000000002aec68 /data/app/~~HmJZrNwUrs1orXn9gkzwoA==/com.matrix.satatyamv-N6vjM8z_IkRTCQPSJZS_dQ==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (BuildId: eb2c97c83bb501fba52a668d79d86d30102202c4)
#6 pc 0x00000000002ae88c /data/app/~~HmJZrNwUrs1orXn9gkzwoA==/com.matrix.satatyamv-N6vjM8z_IkRTCQPSJZS_dQ==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (BuildId: eb2c97c83bb501fba52a668d79d86d30102202c4)
#7 pc 0x00000000002bcc8c /data/app/~~HmJZrNwUrs1orXn9gkzwoA==/com.matrix.satatyamv-N6vjM8z_IkRTCQPSJZS_dQ==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (BuildId: eb2c97c83bb501fba52a668d79d86d30102202c4)
#8 pc 0x00000000002aad54 /data/app/~~HmJZrNwUrs1orXn9gkzwoA==/com.matrix.satatyamv-N6vjM8z_IkRTCQPSJZS_dQ==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (BuildId: eb2c97c83bb501fba52a668d79d86d30102202c4)
#9 pc 0x000000000029d984 /data/app/~~HmJZrNwUrs1orXn9gkzwoA==/com.matrix.satatyamv-N6vjM8z_IkRTCQPSJZS_dQ==/split_config.arm64_v8a.apk!libmonosgen-2.0.so (BuildId: eb2c97c83bb501fba52a668d79d86d30102202c4)
#10 pc 0x000000000000b8a8

Symbolicated Stacktrace:

sejal@Sejals-Mac-mini arm64-v8a % /Users/sejal/Documents/Sejal/android-ndk-r22b/toolchains/llvm/prebuilt/darwin-x86_64/bin/llvm-addr2line -aCifp -e libmonosgen-2.0.so 0x00000000002b1f50
0x2b1f50: sgen_vtable_get_descriptor at /__w/1/s/src/mono/mono/sgen/../metadata/sgen-client-mono.h:29
(inlined by) sgen_client_par_object_get_size at /__w/1/s/src/mono/mono/sgen/../metadata/sgen-client-mono.h:146
sejal@Sejals-Mac-mini arm64-v8a % /Users/sejal/Documents/Sejal/android-ndk-r22b/toolchains/llvm/prebuilt/darwin-x86_64/bin/llvm-addr2line -aCifp -e libmonosgen-2.0.so 0x00000000002b3060
0x2b3060: sgen_safe_object_get_size at /__w/1/s/src/mono/mono/sgen/../../mono/sgen/sgen-gc.h:0
(inlined by) pin_objects_from_nursery_pin_queue at /__w/1/s/src/mono/mono/sgen/sgen-gc.c:671
(inlined by) pin_objects_in_nursery at /__w/1/s/src/mono/mono/sgen/sgen-gc.c:753
sejal@Sejals-Mac-mini arm64-v8a % /Users/sejal/Documents/Sejal/android-ndk-r22b/toolchains/llvm/prebuilt/darwin-x86_64/bin/llvm-addr2line -aCifp -e libmonosgen-2.0.so 0x00000000002b446c
0x2b446c: major_copy_or_mark_from_roots at /__w/1/s/src/mono/mono/sgen/sgen-gc.c:2126
sejal@Sejals-Mac-mini arm64-v8a % /Users/sejal/Documents/Sejal/android-ndk-r22b/toolchains/llvm/prebuilt/darwin-x86_64/bin/llvm-addr2line -aCifp -e libmonosgen-2.0.so 0x00000000002b4f8c
0x2b4f8c: major_start_collection at /__w/1/s/src/mono/mono/sgen/sgen-gc.c:2289
sejal@Sejals-Mac-mini arm64-v8a % /Users/sejal/Documents/Sejal/android-ndk-r22b/toolchains/llvm/prebuilt/darwin-x86_64/bin/llvm-addr2line -aCifp -e libmonosgen-2.0.so 0x00000000002b2c4c
0x2b2c4c: major_do_collection at /__w/1/s/src/mono/mono/sgen/sgen-gc.c:2464
sejal@Sejals-Mac-mini arm64-v8a % /Users/sejal/Documents/Sejal/android-ndk-r22b/toolchains/llvm/prebuilt/darwin-x86_64/bin/llvm-addr2line -aCifp -e libmonosgen-2.0.so 0x00000000002aec68
0x2aec68: sgen_perform_collection_inner at /__w/1/s/src/mono/mono/sgen/sgen-gc.c:2665
(inlined by) sgen_perform_collection at /__w/1/s/src/mono/mono/sgen/sgen-gc.c:2762
sejal@Sejals-Mac-mini arm64-v8a % /Users/sejal/Documents/Sejal/android-ndk-r22b/toolchains/llvm/prebuilt/darwin-x86_64/bin/llvm-addr2line -aCifp -e libmonosgen-2.0.so 0x00000000002ae88c
0x2ae88c: sgen_ensure_free_space at /__w/1/s/src/mono/mono/sgen/sgen-gc.c:2616
sejal@Sejals-Mac-mini arm64-v8a % /Users/sejal/Documents/Sejal/android-ndk-r22b/toolchains/llvm/prebuilt/darwin-x86_64/bin/llvm-addr2line -aCifp -e libmonosgen-2.0.so 0x00000000002bcc8c
0x2bcc8c: sgen_los_alloc_large_inner at /__w/1/s/src/mono/mono/sgen/sgen-los.c:442
sejal@Sejals-Mac-mini arm64-v8a % /Users/sejal/Documents/Sejal/android-ndk-r22b/toolchains/llvm/prebuilt/darwin-x86_64/bin/llvm-addr2line -aCifp -e libmonosgen-2.0.so 0x00000000002aad54
0x2aad54: sgen_alloc_obj_nolock at /__w/1/s/src/mono/mono/sgen/sgen-alloc.c:184
sejal@Sejals-Mac-mini arm64-v8a % /Users/sejal/Documents/Sejal/android-ndk-r22b/toolchains/llvm/prebuilt/darwin-x86_64/bin/llvm-addr2line -aCifp -e libmonosgen-2.0.so 0x000000000029d984
0x29d984: mono_gc_alloc_vector at /__w/1/s/src/mono/mono/metadata/sgen-mono.c:1119

[MihuBot]

I'm a bot. Here are possible related and/or duplicate issues (I may be wrong):

• Android app crashes with error split_config.arm64_v8a.apk!libmonosgen-2.0.so #109921
• [mono] android crash: sgen_client_par_object_get_size [sgen-client-mono.h : 159] #113196

[BrzVlad]

Could you try 9.0.8 as well ? There is an additional gc fix there (#116951)

[SejalH96]

We recently upgraded the project to .NET version 9.0.8. Since the exact steps that led to the crash are not known and it has only been reported in the Play Console, we need to release this version to confirm whether the issue is resolved. The release will take a few days to go live. I’ve also shared the symbolicated stack trace—could you please review it and confirm whether this matches the crash that was previously fixed?

[SejalH96]

@BrzVlad, were you able to find some time to review the stack trace?

We have noticed the following behaviour after updating the .NET version:

.NET 9.0.7

iOS app crashed within 1–1.5 hours

Android app crashed within 7–8 hours

.NET 9.0.8

iOS app crashed after 6–7 hours

Android app crashed after 19–20 hours

The update has certainly improved stability, but it seems there may still be an underlying issue.

[dee480217-cloud]

Lin

[BrzVlad]

@SejalH96 Seems like you are able to reproduce the crash quite reliably in an automated fashion. Does it reproduce also on maccatalyst ? Could you share the repro with us ?

[SejalH96]

Our app only supports Android and iOS and not built for maccatalyst. In xamarin build of same project, the app is not get crashed in iPhone even after 50 hours.