diff --git a/Documentation/arm64/tagged-address-abi.rst b/Documentation/arm64/tagged-address-abi.rst
index d4a85d535bf9..4a9d9c794ee5 100644
--- a/Documentation/arm64/tagged-address-abi.rst
+++ b/Documentation/arm64/tagged-address-abi.rst
@@ -44,8 +44,15 @@ The AArch64 Tagged Address ABI has two stages of relaxation depending
 how the user addresses are used by the kernel:
 
 1. User addresses not accessed by the kernel but used for address space
-   management (e.g. ``mmap()``, ``mprotect()``, ``madvise()``). The use
-   of valid tagged pointers in this context is always allowed.
+   management (e.g. ``mprotect()``, ``madvise()``). The use of valid
+   tagged pointers in this context is allowed with the exception of
+   ``brk()``, ``mmap()`` and the ``new_address`` argument to
+   ``mremap()`` as these have the potential to alias with existing
+   user addresses.
+
+   NOTE: This behaviour changed in v5.6 and so some earlier kernels may
+   incorrectly accept valid tagged pointers for the ``brk()``,
+   ``mmap()`` and ``mremap()`` system calls.
 
 2. User addresses accessed by the kernel (e.g. ``write()``). This ABI
    relaxation is disabled by default and the application thread needs to
diff --git a/mm/mmap.c b/mm/mmap.c
index 4390dbea4aa5..514cc19c5916 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -195,8 +195,6 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
 	bool downgraded = false;
 	LIST_HEAD(uf);
 
-	brk = untagged_addr(brk);
-
 	if (down_write_killable(&mm->mmap_sem))
 		return -EINTR;
 
@@ -1583,8 +1581,6 @@ unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len,
 	struct file *file = NULL;
 	unsigned long retval;
 
-	addr = untagged_addr(addr);
-
 	if (!(flags & MAP_ANONYMOUS)) {
 		audit_mmap_fd(fd, flags);
 		file = fget(fd);
diff --git a/mm/mremap.c b/mm/mremap.c
index 1fc8a29fbe3f..1d98281f7204 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -607,7 +607,6 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
 	LIST_HEAD(uf_unmap);
 
 	addr = untagged_addr(addr);
-	new_addr = untagged_addr(new_addr);
 
 	if (flags & ~(MREMAP_FIXED | MREMAP_MAYMOVE))
 		return ret;