From 4158d899b56870b65b14e866882db103de2f8536 Mon Sep 17 00:00:00 2001
From: 4lDO2 <4lDO2@protonmail.com>
Date: Wed, 24 Jul 2024 22:38:25 +0200
Subject: [PATCH] Probably fix TLB shootdown "diagonal" livelock.

Diagonal as in

Thread A        Thread B
Send to B       Send to A
Wait for B      Wait for A.

I haven't reproduced this bug, but this should fix it, since the wait
steps now checks the local percpu block for pending TLB shootdowns onto
itself.
---
 src/context/memory.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/context/memory.rs b/src/context/memory.rs
index b7d4094fb5..0956c1c092 100644
--- a/src/context/memory.rs
+++ b/src/context/memory.rs
@@ -2898,6 +2898,7 @@ impl<'guard, 'addrsp> Flusher<'guard, 'addrsp> {
         }
 
         while self.state.ackword.load(Ordering::SeqCst) < affected_cpu_count {
+            PercpuBlock::current().maybe_handle_tlb_shootdown();
             core::hint::spin_loop();
         }