kernel/linux.git/drivers/net/hyperv, branch v5.10.259

hv_netvsc: use kmap_local_page in netvsc_copy_to_send_buf

2026-06-19T11:21:47+00:00

[ Upstream commit 004e9ecfe6c5384f9e0b2f6f6389d42ec22789af ] netvsc_copy_to_send_buf() copies page buffer entries into the VMBus send buffer using phys_to_virt() on the entry PFN. Entries for the RNDIS header and the skb linear data come from kmalloc'd memory and are always in the kernel direct map, but entries for skb fragments reference page cache or user pages, which on 32-bit x86 with CONFIG_HIGHMEM=y can live above the LOWMEM boundary. For such a page phys_to_virt() returns an address outside the direct map and the subsequent memcpy() faults on the transmit softirq path, which is fatal. Map the pages with kmap_local_page() instead, handling two properties of the page buffer entries: - pb[i].pfn is a Hyper-V PFN at HV_HYP_PAGE_SIZE (4K) granularity, not a native PFN. Reconstruct the physical address first and derive the native page from it, so the mapping stays correct where PAGE_SIZE > HV_HYP_PAGE_SIZE (e.g. arm64 with 64K pages). - Since commit 41a6328b2c55 ("hv_netvsc: Preserve contiguous PFN grouping in the page buffer array"), an entry describes a full physically contiguous fragment and pb[i].len can exceed PAGE_SIZE, while kmap_local_page() maps a single page. Copy page by page, splitting at native page boundaries. The copy path only handles packets smaller than the send section size (6144 bytes by default); larger packets take the cp_partial path where only the RNDIS header is copied. So entries here are bounded by the section size and a copy is split at most once on 4K-page systems. On !CONFIG_HIGHMEM configs kmap_local_page() folds to page_address() and no mapping work is added. Fixes: c25aaf814a63 ("hyperv: Enable sendbuf mechanism on the send path") Cc: stable@vger.kernel.org Signed-off-by: Anton Leontev Link: https://patch.msgid.link/20260604165938.32033-1-leontyevantony@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

hv_netvsc: Fix panic during namespace deletion with VF

2025-08-28T14:22:54+00:00

[ Upstream commit 33caa208dba6fa639e8a92fd0c8320b652e5550c ] The existing code move the VF NIC to new namespace when NETDEV_REGISTER is received on netvsc NIC. During deletion of the namespace, default_device_exit_batch() >> default_device_exit_net() is called. When netvsc NIC is moved back and registered to the default namespace, it automatically brings VF NIC back to the default namespace. This will cause the default_device_exit_net() >> for_each_netdev_safe loop unable to detect the list end, and hit NULL ptr: [ 231.449420] mana 7870:00:00.0 enP30832s1: Moved VF to namespace with: eth0 [ 231.449656] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 231.450246] #PF: supervisor read access in kernel mode [ 231.450579] #PF: error_code(0x0000) - not-present page [ 231.450916] PGD 17b8a8067 P4D 0 [ 231.451163] Oops: Oops: 0000 [#1] SMP NOPTI [ 231.451450] CPU: 82 UID: 0 PID: 1394 Comm: kworker/u768:1 Not tainted 6.16.0-rc4+ #3 VOLUNTARY [ 231.452042] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024 [ 231.452692] Workqueue: netns cleanup_net [ 231.452947] RIP: 0010:default_device_exit_batch+0x16c/0x3f0 [ 231.453326] Code: c0 0c f5 b3 e8 d5 db fe ff 48 85 c0 74 15 48 c7 c2 f8 fd ca b2 be 10 00 00 00 48 8d 7d c0 e8 7b 77 25 00 49 8b 86 28 01 00 00 <48> 8b 50 10 4c 8b 2a 4c 8d 62 f0 49 83 ed 10 4c 39 e0 0f 84 d6 00 [ 231.454294] RSP: 0018:ff75fc7c9bf9fd00 EFLAGS: 00010246 [ 231.454610] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 61c8864680b583eb [ 231.455094] RDX: ff1fa9f71462d800 RSI: ff75fc7c9bf9fd38 RDI: 0000000030766564 [ 231.455686] RBP: ff75fc7c9bf9fd78 R08: 0000000000000000 R09: 0000000000000000 [ 231.456126] R10: 0000000000000001 R11: 0000000000000004 R12: ff1fa9f70088e340 [ 231.456621] R13: ff1fa9f70088e340 R14: ffffffffb3f50c20 R15: ff1fa9f7103e6340 [ 231.457161] FS: 0000000000000000(0000) GS:ff1faa6783a08000(0000) knlGS:0000000000000000 [ 231.457707] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 231.458031] CR2: 0000000000000010 CR3: 0000000179ab2006 CR4: 0000000000b73ef0 [ 231.458434] Call Trace: [ 231.458600] [ 231.458777] ops_undo_list+0x100/0x220 [ 231.459015] cleanup_net+0x1b8/0x300 [ 231.459285] process_one_work+0x184/0x340 To fix it, move the ns change to a workqueue, and take rtnl_lock to avoid changing the netdev list when default_device_exit_net() is using it. Cc: stable@vger.kernel.org Fixes: 4c262801ea60 ("hv_netvsc: Fix VF namespace also in synthetic NIC NETDEV_REGISTER event") Signed-off-by: Haiyang Zhang Link: https://patch.msgid.link/1754511711-11188-1-git-send-email-haiyangz@linux.microsoft.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

hv_netvsc: Fix VF namespace also in synthetic NIC NETDEV_REGISTER event

2024-11-08T15:22:00+00:00

commit 4c262801ea60c518b5bebc22a09f5b78b3147da2 upstream. The existing code moves VF to the same namespace as the synthetic NIC during netvsc_register_vf(). But, if the synthetic device is moved to a new namespace after the VF registration, the VF won't be moved together. To make the behavior more consistent, add a namespace check for synthetic NIC's NETDEV_REGISTER event (generated during its move), and move the VF if it is not in the same namespace. Cc: stable@vger.kernel.org Fixes: c0a41b887ce6 ("hv_netvsc: move VF to same namespace as netvsc device") Suggested-by: Stephen Hemminger Signed-off-by: Haiyang Zhang Reviewed-by: Simon Horman Link: https://patch.msgid.link/1729275922-17595-1-git-send-email-haiyangz@microsoft.com Signed-off-by: Paolo Abeni Signed-off-by: Greg Kroah-Hartman

hv_netvsc: Register VF in netvsc_probe if NET_DEVICE_REGISTER missed

2024-03-15T14:48:21+00:00

[ Upstream commit 9cae43da9867412f8bd09aee5c8a8dc5e8dc3dc2 ] If hv_netvsc driver is unloaded and reloaded, the NET_DEVICE_REGISTER handler cannot perform VF register successfully as the register call is received before netvsc_probe is finished. This is because we register register_netdevice_notifier() very early( even before vmbus_driver_register()). To fix this, we try to register each such matching VF( if it is visible as a netdevice) at the end of netvsc_probe. Cc: stable@vger.kernel.org Fixes: 85520856466e ("hv_netvsc: Fix race of register_netdevice_notifier and VF register") Suggested-by: Dexuan Cui Signed-off-by: Shradha Gupta Reviewed-by: Haiyang Zhang Reviewed-by: Dexuan Cui Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

hv_netvsc: use netif_is_bond_master() instead of open code

2024-03-15T14:48:21+00:00

[ Upstream commit c60882a4566a0a62dc3a40c85131103aad83dcb3 ] Use netif_is_bond_master() function instead of open code, which is ((event_dev->priv_flags & IFF_BONDING) && (event_dev->flags & IFF_MASTER)). This patch doesn't change logic. Signed-off-by: Juhee Kang Signed-off-by: David S. Miller Stable-dep-of: 9cae43da9867 ("hv_netvsc: Register VF in netvsc_probe if NET_DEVICE_REGISTER missed") Signed-off-by: Sasha Levin

hv_netvsc: Make netvsc/VF binding check both MAC and serial number

2024-03-15T14:48:21+00:00

[ Upstream commit 64ff412ad41fe3a5bf759ff4844dc1382176485c ] Currently the netvsc/VF binding logic only checks the PCI serial number. The Microsoft Azure Network Adapter (MANA) supports multiple net_device interfaces (each such interface is called a "vPort", and has its unique MAC address) which are backed by the same VF PCI device, so the binding logic should check both the MAC address and the PCI serial number. The change should not break any other existing VF drivers, because Hyper-V NIC SR-IOV implementation requires the netvsc network interface and the VF network interface have the same MAC address. Co-developed-by: Haiyang Zhang Signed-off-by: Haiyang Zhang Co-developed-by: Shachar Raindel Signed-off-by: Shachar Raindel Acked-by: Stephen Hemminger Signed-off-by: Dexuan Cui Signed-off-by: David S. Miller Stable-dep-of: 9cae43da9867 ("hv_netvsc: Register VF in netvsc_probe if NET_DEVICE_REGISTER missed") Signed-off-by: Sasha Levin

hv_netvsc: Process NETDEV_GOING_DOWN on VF hot remove

2024-03-15T14:48:21+00:00

[ Upstream commit 34b06a2eee44d469f2e2c013a83e6dac3aff6411 ] On VF hot remove, NETDEV_GOING_DOWN is sent to notify the VF is about to go down. At this time, the VF is still sending/receiving traffic and we request the VSP to switch datapath. On completion, the datapath is switched to synthetic and we can proceed with VF hot remove. Signed-off-by: Long Li Reviewed-by: Haiyang Zhang Signed-off-by: Jakub Kicinski Stable-dep-of: 9cae43da9867 ("hv_netvsc: Register VF in netvsc_probe if NET_DEVICE_REGISTER missed") Signed-off-by: Sasha Levin

hv_netvsc: Wait for completion on request SWITCH_DATA_PATH

2024-03-15T14:48:21+00:00

[ Upstream commit 8b31f8c982b738e4130539e47f03967c599d8e22 ] The completion indicates if NVSP_MSG4_TYPE_SWITCH_DATA_PATH has been processed by the VSP. The traffic is steered to VF or synthetic after we receive this completion. Signed-off-by: Long Li Reported-by: kernel test robot Signed-off-by: Jakub Kicinski Stable-dep-of: 9cae43da9867 ("hv_netvsc: Register VF in netvsc_probe if NET_DEVICE_REGISTER missed") Signed-off-by: Sasha Levin

hv_netvsc: Use vmbus_requestor to generate transaction IDs for VMBus hardening

2024-03-15T14:48:21+00:00

[ Upstream commit 4d18fcc95f50950a99bd940d4e61a983f91d267a ] Currently, pointers to guest memory are passed to Hyper-V as transaction IDs in netvsc. In the face of errors or malicious behavior in Hyper-V, netvsc should not expose or trust the transaction IDs returned by Hyper-V to be valid guest memory addresses. Instead, use small integers generated by vmbus_requestor as requests (transaction) IDs. Signed-off-by: Andres Beltran Co-developed-by: Andrea Parri (Microsoft) Signed-off-by: Andrea Parri (Microsoft) Reviewed-by: Michael Kelley Acked-by: Jakub Kicinski Reviewed-by: Wei Liu Cc: "David S. Miller" Cc: Jakub Kicinski Cc: netdev@vger.kernel.org Link: https://lore.kernel.org/r/20201109100402.8946-4-parri.andrea@gmail.com Signed-off-by: Wei Liu Stable-dep-of: 9cae43da9867 ("hv_netvsc: Register VF in netvsc_probe if NET_DEVICE_REGISTER missed") Signed-off-by: Sasha Levin

hv_netvsc: Fix race condition between netvsc_probe and netvsc_remove

2024-02-23T07:42:27+00:00

commit e0526ec5360a48ad3ab2e26e802b0532302a7e11 upstream. In commit ac5047671758 ("hv_netvsc: Disable NAPI before closing the VMBus channel"), napi_disable was getting called for all channels, including all subchannels without confirming if they are enabled or not. This caused hv_netvsc getting hung at napi_disable, when netvsc_probe() has finished running but nvdev->subchan_work has not started yet. netvsc_subchan_work() -> rndis_set_subchannel() has not created the sub-channels and because of that netvsc_sc_open() is not running. netvsc_remove() calls cancel_work_sync(&nvdev->subchan_work), for which netvsc_subchan_work did not run. netif_napi_add() sets the bit NAPI_STATE_SCHED because it ensures NAPI cannot be scheduled. Then netvsc_sc_open() -> napi_enable will clear the NAPIF_STATE_SCHED bit, so it can be scheduled. napi_disable() does the opposite. Now during netvsc_device_remove(), when napi_disable is called for those subchannels, napi_disable gets stuck on infinite msleep. This fix addresses this problem by ensuring that napi_disable() is not getting called for non-enabled NAPI struct. But netif_napi_del() is still necessary for these non-enabled NAPI struct for cleanup purpose. Call trace: [ 654.559417] task:modprobe state:D stack: 0 pid: 2321 ppid: 1091 flags:0x00004002 [ 654.568030] Call Trace: [ 654.571221] [ 654.573790] __schedule+0x2d6/0x960 [ 654.577733] schedule+0x69/0xf0 [ 654.581214] schedule_timeout+0x87/0x140 [ 654.585463] ? __bpf_trace_tick_stop+0x20/0x20 [ 654.590291] msleep+0x2d/0x40 [ 654.593625] napi_disable+0x2b/0x80 [ 654.597437] netvsc_device_remove+0x8a/0x1f0 [hv_netvsc] [ 654.603935] rndis_filter_device_remove+0x194/0x1c0 [hv_netvsc] [ 654.611101] ? do_wait_intr+0xb0/0xb0 [ 654.615753] netvsc_remove+0x7c/0x120 [hv_netvsc] [ 654.621675] vmbus_remove+0x27/0x40 [hv_vmbus] Cc: stable@vger.kernel.org Fixes: ac5047671758 ("hv_netvsc: Disable NAPI before closing the VMBus channel") Signed-off-by: Souradeep Chakrabarti Reviewed-by: Dexuan Cui Reviewed-by: Haiyang Zhang Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/1706686551-28510-1-git-send-email-schakrabarti@linux.microsoft.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman