From 67dbec82f4f05a416a78a560a726553beaa7a223 Mon Sep 17 00:00:00 2001
From: Mike Pall <mike>
Date: Wed, 10 Mar 2021 19:58:31 +0100
Subject: [PATCH] Linux/ARM64: Make mremap() non-moving due to VA space woes.

This reduces overall performance on ARM64, but we have no choice.
Linux kernel default userspace VA is 48 bit, but we'd need 47 bit.
mremap() ignores address hints due to a kernel API issue. The mapping
may move to an undesired address which will cause an assert or crash.

Reported by Raymond W. Ko.
---
 src/lj_alloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/lj_alloc.c b/src/lj_alloc.c
index 21fb7af5..165203fa 100644
--- a/src/lj_alloc.c
+++ b/src/lj_alloc.c
@@ -365,7 +365,7 @@ static void *CALL_MREMAP_(void *ptr, size_t osz, size_t nsz, int flags)
 #define CALL_MREMAP(addr, osz, nsz, mv) CALL_MREMAP_((addr), (osz), (nsz), (mv))
 #define CALL_MREMAP_NOMOVE	0
 #define CALL_MREMAP_MAYMOVE	1
-#if LJ_64 && !LJ_GC64
+#if LJ_64 && (!LJ_GC64 || LJ_TARGET_ARM64)
 #define CALL_MREMAP_MV		CALL_MREMAP_NOMOVE
 #else
 #define CALL_MREMAP_MV		CALL_MREMAP_MAYMOVE