[PATCH 6.0 328/862] vhost/vsock: Use kvmalloc/kvfree for larger packets.

From: Greg Kroah-Hartman
Date: Wed Oct 19 2022 - 05:02:24 EST


From: Junichi Uekawa <uekawa@xxxxxxxxxxxx>

[ Upstream commit 0e3f72931fc47bb81686020cc643cde5d9cd0bb8 ]

When copying a large file over sftp over vsock, data size is usually 32kB,
and kmalloc seems to fail to try to allocate 32 32kB regions.

vhost-5837: page allocation failure: order:4, mode:0x24040c0
Call Trace:
[<ffffffffb6a0df64>] dump_stack+0x97/0xdb
[<ffffffffb68d6aed>] warn_alloc_failed+0x10f/0x138
[<ffffffffb68d868a>] ? __alloc_pages_direct_compact+0x38/0xc8
[<ffffffffb664619f>] __alloc_pages_nodemask+0x84c/0x90d
[<ffffffffb6646e56>] alloc_kmem_pages+0x17/0x19
[<ffffffffb6653a26>] kmalloc_order_trace+0x2b/0xdb
[<ffffffffb66682f3>] __kmalloc+0x177/0x1f7
[<ffffffffb66e0d94>] ? copy_from_iter+0x8d/0x31d
[<ffffffffc0689ab7>] vhost_vsock_handle_tx_kick+0x1fa/0x301 [vhost_vsock]
[<ffffffffc06828d9>] vhost_worker+0xf7/0x157 [vhost]
[<ffffffffb683ddce>] kthread+0xfd/0x105
[<ffffffffc06827e2>] ? vhost_dev_set_owner+0x22e/0x22e [vhost]
[<ffffffffb683dcd1>] ? flush_kthread_worker+0xf3/0xf3
[<ffffffffb6eb332e>] ret_from_fork+0x4e/0x80
[<ffffffffb683dcd1>] ? flush_kthread_worker+0xf3/0xf3

Work around by doing kvmalloc instead.

Fixes: 433fc58e6bf2 ("VSOCK: Introduce vhost_vsock.ko")
Signed-off-by: Junichi Uekawa <uekawa@xxxxxxxxxxxx>
Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220928064538.667678-1-uekawa@xxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/vhost/vsock.c | 2 +-
net/vmw_vsock/virtio_transport_common.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
index 368330417bde..5703775af129 100644
--- a/drivers/vhost/vsock.c
+++ b/drivers/vhost/vsock.c
@@ -393,7 +393,7 @@ vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq,
return NULL;
}

- pkt->buf = kmalloc(pkt->len, GFP_KERNEL);
+ pkt->buf = kvmalloc(pkt->len, GFP_KERNEL);
if (!pkt->buf) {
kfree(pkt);
return NULL;
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index ec2c2afbf0d0..3a12aee33e92 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -1342,7 +1342,7 @@ EXPORT_SYMBOL_GPL(virtio_transport_recv_pkt);

void virtio_transport_free_pkt(struct virtio_vsock_pkt *pkt)
{
- kfree(pkt->buf);
+ kvfree(pkt->buf);
kfree(pkt);
}
EXPORT_SYMBOL_GPL(virtio_transport_free_pkt);
--
2.35.1