From: Magnus Karlsson <magnus.karlsson@intel.com>
Date: Tue, 14 Jan 2020 10:49:25 +0100
Subject: xsk: Support allocations of large umems
Patch-mainline: v5.6-rc1
Git-commit: d3a56931f9c8644a52e7a6735954c84ea895e8c3
References: bsc#1176447

When registering a umem area that is sufficiently large (>1G on an
x86), kmalloc cannot be used to allocate one of the internal data
structures, as the size requested gets too large. Use kvmalloc instead
that falls back on vmalloc if the allocation is too large for kmalloc.

Also add accounting for this structure as it is triggered by a user
space action (the XDP_UMEM_REG setsockopt) and it is by far the
largest structure of kernel allocated memory in xsk.

Reported-by: Ryan Goodfellow <rgoodfel@isi.edu>
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Link: https://lore.kernel.org/bpf/1578995365-7050-1-git-send-email-magnus.karlsson@intel.com
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/xdp/xdp_umem.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

--- a/net/xdp/xdp_umem.c
+++ b/net/xdp/xdp_umem.c
@@ -256,7 +256,7 @@ static void xdp_umem_release(struct xdp_
 	xdp_umem_unmap_pages(umem);
 	xdp_umem_unpin_pages(umem);
 
-	kfree(umem->pages);
+	kvfree(umem->pages);
 	umem->pages = NULL;
 
 	xdp_umem_unaccount_pages(umem);
@@ -416,7 +416,8 @@ static int xdp_umem_reg(struct xdp_umem
 	if (err)
 		goto out_account;
 
-	umem->pages = kcalloc(umem->npgs, sizeof(*umem->pages), GFP_KERNEL);
+	umem->pages = kvcalloc(umem->npgs, sizeof(*umem->pages),
+			       GFP_KERNEL_ACCOUNT);
 	if (!umem->pages) {
 		err = -ENOMEM;
 		goto out_pin;
@@ -426,7 +427,7 @@ static int xdp_umem_reg(struct xdp_umem
 	if (!err)
 		return 0;
 
-	kfree(umem->pages);
+	kvfree(umem->pages);
 
 out_pin:
 	xdp_umem_unpin_pages(umem);