Server crash on player disconnect (something in PlayerQuitEvent)

[gummianka]

Stack trace

[10:30:13 INFO]: gummi_anka lost connection: Disconnected
[10:30:13 ERROR]: Thread Region Scheduler Thread #0 failed main thread check: Cannot remove entity off-main
java.lang.Throwable: null
  at io.papermc.paper.util.TickThread.ensureTickThread(TickThread.java:78) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.world.entity.Entity.setRemoved(Entity.java:5602) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.world.entity.Entity.remove(Entity.java:708) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.world.entity.LivingEntity.remove(LivingEntity.java:783) ~[?:?]
  at net.minecraft.world.entity.player.Player.remove(Player.java:1522) ~[?:?]
  at net.minecraft.server.level.ServerLevel.removePlayerImmediately(ServerLevel.java:1932) ~[?:?]
  at net.minecraft.server.players.PlayerList.remove(PlayerList.java:757) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.server.players.PlayerList.remove(PlayerList.java:696) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.server.network.ServerGamePacketListenerImpl.removePlayerFromWorld(ServerGamePacketListenerImpl.java:2143) ~[?:?]
  at net.minecraft.server.network.ServerGamePacketListenerImpl.onDisconnect(ServerGamePacketListenerImpl.java:2121) ~[?:?]
  at net.minecraft.server.network.ServerGamePacketListenerImpl.onDisconnect(ServerGamePacketListenerImpl.java:2108) ~[?:?]
  at net.minecraft.network.Connection.handleDisconnection(Connection.java:894) ~[?:?]
  at io.papermc.paper.threadedregions.RegionizedWorldData.tickConnections(RegionizedWorldData.java:516) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.server.MinecraftServer.tickChildren(MinecraftServer.java:1843) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.server.dedicated.DedicatedServer.tickChildren(DedicatedServer.java:447) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.server.MinecraftServer.tickServer(MinecraftServer.java:1657) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at io.papermc.paper.threadedregions.TickRegions$ConcreteRegionTickHandle.tickRegion(TickRegions.java:407) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at io.papermc.paper.threadedregions.TickRegionScheduler$RegionScheduleHandle.runTick(TickRegionScheduler.java:404) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at ca.spottedleaf.concurrentutil.scheduler.SchedulerThreadPool$TickThreadRunner.run(SchedulerThreadPool.java:525) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at java.lang.Thread.run(Thread.java:1583) ~[?:?]
[10:30:13 ERROR]: [io.papermc.paper.threadedregions.TickRegionScheduler] Region #1 centered at chunk [41, 53] in world 'arena' failed to tick:
java.lang.IllegalStateException: Cannot remove entity off-main
  at io.papermc.paper.util.TickThread.ensureTickThread(TickThread.java:79) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.world.entity.Entity.setRemoved(Entity.java:5602) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.world.entity.Entity.remove(Entity.java:708) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.world.entity.LivingEntity.remove(LivingEntity.java:783) ~[?:?]
  at net.minecraft.world.entity.player.Player.remove(Player.java:1522) ~[?:?]
  at net.minecraft.server.level.ServerLevel.removePlayerImmediately(ServerLevel.java:1932) ~[?:?]
  at net.minecraft.server.players.PlayerList.remove(PlayerList.java:757) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.server.players.PlayerList.remove(PlayerList.java:696) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.server.network.ServerGamePacketListenerImpl.removePlayerFromWorld(ServerGamePacketListenerImpl.java:2143) ~[?:?]
  at net.minecraft.server.network.ServerGamePacketListenerImpl.onDisconnect(ServerGamePacketListenerImpl.java:2121) ~[?:?]
  at net.minecraft.server.network.ServerGamePacketListenerImpl.onDisconnect(ServerGamePacketListenerImpl.java:2108) ~[?:?]
  at net.minecraft.network.Connection.handleDisconnection(Connection.java:894) ~[?:?]
  at io.papermc.paper.threadedregions.RegionizedWorldData.tickConnections(RegionizedWorldData.java:516) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.server.MinecraftServer.tickChildren(MinecraftServer.java:1843) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.server.dedicated.DedicatedServer.tickChildren(DedicatedServer.java:447) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at net.minecraft.server.MinecraftServer.tickServer(MinecraftServer.java:1657) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at io.papermc.paper.threadedregions.TickRegions$ConcreteRegionTickHandle.tickRegion(TickRegions.java:407) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at io.papermc.paper.threadedregions.TickRegionScheduler$RegionScheduleHandle.runTick(TickRegionScheduler.java:404) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at ca.spottedleaf.concurrentutil.scheduler.SchedulerThreadPool$TickThreadRunner.run(SchedulerThreadPool.java:525) ~[folia-1.20.4.jar:git-Folia-"2986554"]
  at java.lang.Thread.run(Thread.java:1583) ~[?:?]

Plugin and Datapack List

MyOwnPlugin, GrimAC, Chunky, ProtocolLib, ViaBackwards, ViaVersion, WorldEdit, spark

Actions to reproduce (if known)

I have my own duels minigame plugin, when a player leaves from a duel (disconnect, command) I call:

player.teleportAsync(loc)
player.getInventory().clear();
player.getAttribute(Attribute.GENERIC_MAX_HEALTH).setBaseValue(20);
player.setHealth(20);
player.setFoodLevel(20);
player.setSaturation(0);
player.setExhaustion(0);
player.setFireTicks(0);

for (PotionEffect effect : player.getActivePotionEffects()) {
    player.removePotionEffect(effect.getType());
}

On paper it was fine to do this on PlayerQuitEvent, I have disabled calling these methods and the server stopped crashing on player disconnect.

Folia version

git-Folia-"2986554" (MC: 1.20.4) (Implementing API version 1.20.4-R0.1-SNAPSHOT) (Git: 2986554)

Other

I patched folia myself for some changes for my server, but also on "clear" folia with last commit 25ee657 I can reproduce same issue

[electronicboy]

We cannot accept stack traces from software that isn't ours

[gummianka]

I tried to reproduce this issue on full empty server, only with plugin with PlayerQuitEvent, tried to teleport player to different worlds, but there is no crash.

But I can still reproduce this crash with my plugins on clear folia. This stack traces doesnt contains my methods, that is why I created this issue

This server is running Folia version git-Folia-"25ee657" (MC: 1.20.4) (Implementing API version 1.20.4-R0.1-SNAPSHOT) (Git: 25ee657)\nYou are running the latest version

[14:34:00] [Region Scheduler Thread #1/INFO]: gummi_anka lost connection: Disconnected
[14:34:00] [Region Scheduler Thread #1/ERROR]: Thread Region Scheduler Thread #1 failed main thread check: Cannot remove entity off-main
java.lang.Throwable: null
	at io.papermc.paper.util.TickThread.ensureTickThread(TickThread.java:78) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.world.entity.Entity.setRemoved(Entity.java:5588) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.world.entity.Entity.remove(Entity.java:708) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.world.entity.LivingEntity.remove(LivingEntity.java:783) ~[?:?]
	at net.minecraft.world.entity.player.Player.remove(Player.java:1522) ~[?:?]
	at net.minecraft.server.level.ServerLevel.removePlayerImmediately(ServerLevel.java:1932) ~[?:?]
	at net.minecraft.server.players.PlayerList.remove(PlayerList.java:757) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.server.players.PlayerList.remove(PlayerList.java:696) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.server.network.ServerGamePacketListenerImpl.removePlayerFromWorld(ServerGamePacketListenerImpl.java:2143) ~[?:?]
	at net.minecraft.server.network.ServerGamePacketListenerImpl.onDisconnect(ServerGamePacketListenerImpl.java:2121) ~[?:?]
	at net.minecraft.server.network.ServerGamePacketListenerImpl.onDisconnect(ServerGamePacketListenerImpl.java:2108) ~[?:?]
	at net.minecraft.network.Connection.handleDisconnection(Connection.java:894) ~[?:?]
	at io.papermc.paper.threadedregions.RegionizedWorldData.tickConnections(RegionizedWorldData.java:516) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.server.MinecraftServer.tickChildren(MinecraftServer.java:1843) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.server.dedicated.DedicatedServer.tickChildren(DedicatedServer.java:447) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.server.MinecraftServer.tickServer(MinecraftServer.java:1657) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at io.papermc.paper.threadedregions.TickRegions$ConcreteRegionTickHandle.tickRegion(TickRegions.java:407) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at io.papermc.paper.threadedregions.TickRegionScheduler$RegionScheduleHandle.runTick(TickRegionScheduler.java:404) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at ca.spottedleaf.concurrentutil.scheduler.SchedulerThreadPool$TickThreadRunner.run(SchedulerThreadPool.java:525) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at java.lang.Thread.run(Thread.java:1583) ~[?:?]
[14:34:00] [Region Scheduler Thread #1/ERROR]: [io.papermc.paper.threadedregions.TickRegionScheduler] Region #1 centered at chunk [41, 53] in world 'arena' failed to tick:
java.lang.IllegalStateException: Cannot remove entity off-main
	at io.papermc.paper.util.TickThread.ensureTickThread(TickThread.java:79) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.world.entity.Entity.setRemoved(Entity.java:5588) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.world.entity.Entity.remove(Entity.java:708) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.world.entity.LivingEntity.remove(LivingEntity.java:783) ~[?:?]
	at net.minecraft.world.entity.player.Player.remove(Player.java:1522) ~[?:?]
	at net.minecraft.server.level.ServerLevel.removePlayerImmediately(ServerLevel.java:1932) ~[?:?]
	at net.minecraft.server.players.PlayerList.remove(PlayerList.java:757) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.server.players.PlayerList.remove(PlayerList.java:696) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.server.network.ServerGamePacketListenerImpl.removePlayerFromWorld(ServerGamePacketListenerImpl.java:2143) ~[?:?]
	at net.minecraft.server.network.ServerGamePacketListenerImpl.onDisconnect(ServerGamePacketListenerImpl.java:2121) ~[?:?]
	at net.minecraft.server.network.ServerGamePacketListenerImpl.onDisconnect(ServerGamePacketListenerImpl.java:2108) ~[?:?]
	at net.minecraft.network.Connection.handleDisconnection(Connection.java:894) ~[?:?]
	at io.papermc.paper.threadedregions.RegionizedWorldData.tickConnections(RegionizedWorldData.java:516) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.server.MinecraftServer.tickChildren(MinecraftServer.java:1843) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.server.dedicated.DedicatedServer.tickChildren(DedicatedServer.java:447) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at net.minecraft.server.MinecraftServer.tickServer(MinecraftServer.java:1657) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at io.papermc.paper.threadedregions.TickRegions$ConcreteRegionTickHandle.tickRegion(TickRegions.java:407) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at io.papermc.paper.threadedregions.TickRegionScheduler$RegionScheduleHandle.runTick(TickRegionScheduler.java:404) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at ca.spottedleaf.concurrentutil.scheduler.SchedulerThreadPool$TickThreadRunner.run(SchedulerThreadPool.java:525) ~[folia-1.20.4.jar:git-Folia-"25ee657"]
	at java.lang.Thread.run(Thread.java:1583) ~[?:?]
[14:34:00] [Region shutdown thread/INFO]: [RegionShutdownThread] Awaiting scheduler termination for 60s
[14:34:00] [Region shutdown thread/INFO]: [RegionShutdownThread] Scheduler halted
[14:34:00] [Region shutdown thread/INFO]: Stopping server

[PedroMPagani]

player.teleportAsync(loc)
player.getInventory().clear();
player.getAttribute(Attribute.GENERIC_MAX_HEALTH).setBaseValue(20);
player.setHealth(20);
player.setFoodLevel(20);
player.setSaturation(0);
player.setExhaustion(0);
player.setFireTicks(0);

for (PotionEffect effect : player.getActivePotionEffects()) {
player.removePotionEffect(effect.getType());
}

these actions on a player quit are kind of "dumb", you should schedule those actions for the new player join event instead