From: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= <bjorn.topel@intel.com>
Date: Mon, 7 May 2018 19:43:50 +0200
Subject: xsk: fix 64-bit division
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Patch-mainline: v4.18-rc1
Git-commit: ea7e3435297c6ba3c8ae51db6ea48f1ed657dc5c
References: bsc#1109837

i386 builds report:
  net/xdp/xdp_umem.o: In function `xdp_umem_reg':
  xdp_umem.c:(.text+0x47e): undefined reference to `__udivdi3'

This fix uses div_u64 instead of the GCC built-in.

Fixes: c0c77d8fb787 ("xsk: add user memory registration support sockopt")
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/xdp/xdp_umem.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/xdp/xdp_umem.c
+++ b/net/xdp/xdp_umem.c
@@ -204,7 +204,7 @@ int xdp_umem_reg(struct xdp_umem *umem,
 	if ((addr + size) < addr)
 		return -EINVAL;
 
-	nframes = size / frame_size;
+	nframes = (unsigned int)div_u64(size, frame_size);
 	if (nframes == 0 || nframes > UINT_MAX)
 		return -EINVAL;