[PATCH V2] Netvsc: Call hv_unmap_memory() in the netvsc_device_remove()
From: Tianyu Lan <hidden>
Date: 2022-02-08 14:27:07
Also in:
lkml, netdev
Subsystem:
hyper-v/azure core and drivers, networking drivers, the rest · Maintainers:
"K. Y. Srinivasan", Haiyang Zhang, Wei Liu, Dexuan Cui, Long Li, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Tianyu Lan <redacted>
netvsc_device_remove() calls vunmap() inside which should not be
called in the interrupt context. Current code calls hv_unmap_memory()
in the free_netvsc_device() which is rcu callback and maybe called
in the interrupt context. This will trigger BUG_ON(in_interrupt())
in the vunmap(). Fix it via moving hv_unmap_memory() to netvsc_device_
remove().
Fixes: 846da38de0e8 ("net: netvsc: Add Isolation VM support for netvsc driver")
Signed-off-by: Tianyu Lan <redacted>
---
Change since v1:
* Call hv_unmap_memory() before free_netvsc_device() in the
netvsc_device_remove().
---
drivers/net/hyperv/netvsc.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index afa81a9480cc..e675d1016c3c 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c@@ -154,19 +154,15 @@ static void free_netvsc_device(struct rcu_head *head) kfree(nvdev->extension); - if (nvdev->recv_original_buf) { - hv_unmap_memory(nvdev->recv_buf); + if (nvdev->recv_original_buf) vfree(nvdev->recv_original_buf); - } else { + else vfree(nvdev->recv_buf); - } - if (nvdev->send_original_buf) { - hv_unmap_memory(nvdev->send_buf); + if (nvdev->send_original_buf) vfree(nvdev->send_original_buf); - } else { + else vfree(nvdev->send_buf); - } bitmap_free(nvdev->send_section_map);
@@ -765,6 +761,12 @@ void netvsc_device_remove(struct hv_device *device) netvsc_teardown_send_gpadl(device, net_device, ndev); } + if (net_device->recv_original_buf) + hv_unmap_memory(net_device->recv_buf); + + if (net_device->send_original_buf) + hv_unmap_memory(net_device->send_buf); + /* Release all resources */ free_netvsc_device_rcu(net_device); }
@@ -1821,6 +1823,12 @@ struct netvsc_device *netvsc_device_add(struct hv_device *device, netif_napi_del(&net_device->chan_table[0].napi); cleanup2: + if (net_device->recv_original_buf) + hv_unmap_memory(net_device->recv_buf); + + if (net_device->send_original_buf) + hv_unmap_memory(net_device->send_buf); + free_netvsc_device(&net_device->rcu); return ERR_PTR(ret);
--
2.25.1