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Date: Wed, 17 Jan 2024 14:39:21 -0800
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Message-ID: <20240117223922.1445327-1-lokeshgidra@google.com>
Subject: [PATCH] userfaultfd: fix return error if mmap_changing is non-zero in
 MOVE ioctl
From: Lokesh Gidra <lokeshgidra@google.com>
To: akpm@linux-foundation.org
Cc: lokeshgidra@google.com, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, 
	linux-kernel@vger.kernel.org, selinux@vger.kernel.org, surenb@google.com, 
	kernel-team@android.com, aarcange@redhat.com, peterx@redhat.com, 
	david@redhat.com, axelrasmussen@google.com, bgeffon@google.com, 
	willy@infradead.org, jannh@google.com, kaleshsingh@google.com, 
	ngeoffray@google.com
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To be consistent with other uffd ioctl's returning EAGAIN when
mmap_changing is detected, we should change UFFDIO_MOVE to do the same.

Signed-off-by: Lokesh Gidra <lokeshgidra@google.com>
---
 fs/userfaultfd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 959551ff9a95..05c8e8a05427 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -2047,7 +2047,7 @@ static int userfaultfd_move(struct userfaultfd_ctx *ctx,
 			ret = move_pages(ctx, mm, uffdio_move.dst, uffdio_move.src,
 					 uffdio_move.len, uffdio_move.mode);
 		else
-			ret = -EINVAL;
+			ret = -EAGAIN;
 
 		mmap_read_unlock(mm);
 		mmput(mm);
-- 
2.43.0.429.g432eaa2c6b-goog