Server deadlock when using corporea index immediately after logging in or something idk it's weird

[quat1024]

using 410-fabric-snapshot.jar in #betas

• place corporea index
• place a master spark on top of it
• relog (due to the hitbox shenanigans, might not have to do this after the fix) relogging appears to be required as of https://github.com/Vazkii/Botania/commit/34d64ccc4652f65390358bfd661c6e8c35636775
• perform a request at the corporea index
• deadlock

Looks like calling ServerChunkManager#getChunk from a packet handler explodes. In Forge this probably used an event that got executed on the main thread wait it still needs to cancel

Complete stacktrace: https://paste.ee/p/kXq2g

Stacktrace of the server thread:

"Server thread@18302" prio=5 tid=0x43 nid=NA waiting
  java.lang.Thread.State: WAITING
      at sun.misc.Unsafe.park(Unsafe.java:-1)
      at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
      at java.util.concurrent.CompletableFuture$Signaller.block(CompletableFuture.java:1693)
      at java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3323)
      at java.util.concurrent.CompletableFuture.waitingGet(CompletableFuture.java:1729)
      at java.util.concurrent.CompletableFuture.join(CompletableFuture.java:1934)
      at net.minecraft.server.world.ServerChunkManager.getChunk(ServerChunkManager.java:113)
      at net.minecraft.world.chunk.ChunkManager.getWorldChunk(ChunkManager.java:14)
      at net.minecraft.world.World.getEntitiesByClass(World.java:720)
      at vazkii.botania.common.impl.corporea.CorporeaHelperImpl.getSparkForBlock(CorporeaHelperImpl.java:144)
      at vazkii.botania.common.block.tile.corporea.TileCorporeaBase.getSpark(TileCorporeaBase.java:24)
      at vazkii.botania.common.block.tile.corporea.TileCorporeaIndex$InputHandler.onChatMessage(TileCorporeaIndex.java:376)
      at net.minecraft.server.network.ServerPlayNetworkHandler.handler$zkc000$handleCorporeaRequest(MixinServerPlayNetworkHandler.java:26)
      at net.minecraft.server.network.ServerPlayNetworkHandler.onGameMessage(ServerPlayNetworkHandler.java:1035)
      at net.minecraft.network.packet.c2s.play.ChatMessageC2SPacket.apply(ChatMessageC2SPacket.java:31)
      at net.minecraft.network.packet.c2s.play.ChatMessageC2SPacket.apply(ChatMessageC2SPacket.java:12)
      at net.minecraft.network.NetworkThreadUtils.method_11072(NetworkThreadUtils.java:20)
      at net.minecraft.network.NetworkThreadUtils$$Lambda$5742.551374760.run(Unknown Source:-1)
      at net.minecraft.server.ServerTask.run(ServerTask.java:17)
      at net.minecraft.util.thread.ThreadExecutor.executeTask(ThreadExecutor.java:136)
      at net.minecraft.util.thread.ReentrantThreadExecutor.executeTask(ReentrantThreadExecutor.java:22)
      at net.minecraft.server.MinecraftServer.executeTask(MinecraftServer.java:749)
      at net.minecraft.server.MinecraftServer.executeTask(MinecraftServer.java:1724)
      at net.minecraft.util.thread.ThreadExecutor.runTask(ThreadExecutor.java:109)
      at net.minecraft.server.MinecraftServer.method_20415(MinecraftServer.java:729)
      at net.minecraft.server.MinecraftServer.runTask(MinecraftServer.java:723)
      at net.minecraft.util.thread.ThreadExecutor.runTasks(ThreadExecutor.java:119)
      at net.minecraft.server.MinecraftServer.method_16208(MinecraftServer.java:709)
      at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:663)
      at net.minecraft.server.MinecraftServer.method_29739(MinecraftServer.java:224)
      at net.minecraft.server.MinecraftServer$$Lambda$5282.1403924920.run(Unknown Source:-1)
      at java.lang.Thread.run(Thread.java:748)

[quat1024]

I have a way better time reproing this when I activate the corporea index immediately after loading into the world, btw (Dunno how long the window is but maybe 2-3 seconds)

[quat1024]

I think you actually have to relog, as well. like if you do it first thing after opening the game, it will not deadlock. you need to open the world, close the world, open it again and immediately send a chat message, then the game hangs.

i think

[Hubry]

Reproduced on Forge, doing basically the exact same things by accident. Amazing.