linux-stable.git/drivers/net/hyperv, branch linux-5.15.y

hv_netvsc: Fix panic during namespace deletion with VF

2025-08-28T14:24:31+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

2024-11-01T00:52:38+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: Fix race condition between netvsc_probe and netvsc_remove

2024-02-23T07:55:07+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

hv_netvsc: Calculate correct ring size when PAGE_SIZE is not 4 Kbytes

2024-02-23T07:54:31+00:00

commit 6941f67ad37d5465b75b9ffc498fcf6897a3c00e upstream.

Current code in netvsc_drv_init() incorrectly assumes that PAGE_SIZE
is 4 Kbytes, which is wrong on ARM64 with 16K or 64K page size. As a
result, the default VMBus ring buffer size on ARM64 with 64K page size
is 8 Mbytes instead of the expected 512 Kbytes. While this doesn't break
anything, a typical VM with 8 vCPUs and 8 netvsc channels wastes 120
Mbytes (8 channels * 2 ring buffers/channel * 7.5 Mbytes/ring buffer).

Unfortunately, the module parameter specifying the ring buffer size
is in units of 4 Kbyte pages. Ideally, it should be in units that
are independent of PAGE_SIZE, but backwards compatibility prevents
changing that now.

Fix this by having netvsc_drv_init() hardcode 4096 instead of using
PAGE_SIZE when calculating the ring buffer size in bytes. Also
use the VMBUS_RING_SIZE macro to ensure proper alignment when running
with page size larger than 4K.

Cc:  # 5.15.x
Fixes: 7aff79e297ee ("Drivers: hv: Enable Hyper-V code to be built on ARM64")
Signed-off-by: Michael Kelley 
Link: https://lore.kernel.org/r/20240122162028.348885-1-mhklinux@outlook.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: rndis_filter needs to select NLS

2023-12-13T17:36:34+00:00

[ Upstream commit 6c89f49964375c904cea33c0247467873f4daf2c ]

rndis_filter uses utf8s_to_utf16s() which is provided by setting
NLS, so select NLS to fix the build error:

ERROR: modpost: "utf8s_to_utf16s" [drivers/net/hyperv/hv_netvsc.ko] undefined!

Fixes: 1ce09e899d28 ("hyperv: Add support for setting MAC from within guests")
Signed-off-by: Randy Dunlap 
Cc: Haiyang Zhang 
Cc: K. Y. Srinivasan 
Cc: Wei Liu 
Cc: Dexuan Cui 
Reviewed-by: Simon Horman 
Tested-by: Simon Horman  # build-tested
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20231130055853.19069-1-rdunlap@infradead.org
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

hv_netvsc: fix race of netvsc and VF register_netdevice

2023-12-08T07:48:02+00:00

[ Upstream commit d30fb712e52964f2cf9a9c14cf67078394044837 ]

The rtnl lock also needs to be held before rndis_filter_device_add()
which advertises nvsp_2_vsc_capability / sriov bit, and triggers
VF NIC offering and registering. If VF NIC finished register_netdev()
earlier it may cause name based config failure.

To fix this issue, move the call to rtnl_lock() before
rndis_filter_device_add(), so VF will be registered later than netvsc
/ synthetic NIC, and gets a name numbered (ethX) after netvsc.

Cc: stable@vger.kernel.org
Fixes: e04e7a7bbd4b ("hv_netvsc: Fix a deadlock by getting rtnl lock earlier in netvsc_probe()")
Reported-by: Dexuan Cui 
Signed-off-by: Haiyang Zhang 
Reviewed-by: Wojciech Drewek 
Reviewed-by: Simon Horman 
Reviewed-by: Dexuan Cui 
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

hv_netvsc: Mark VF as slave before exposing it to user-mode

2023-12-03T06:31:24+00:00

commit c807d6cd089d2f4951baa838081ec5ae3e2360f8 upstream.

When a VF is being exposed form the kernel, it should be marked as "slave"
before exposing to the user-mode. The VF is not usable without netvsc
running as master. The user-mode should never see a VF without the "slave"
flag.

This commit moves the code of setting the slave flag to the time before
VF is exposed to user-mode.

Cc: stable@vger.kernel.org
Fixes: 0c195567a8f6 ("netvsc: transparent VF management")
Signed-off-by: Long Li 
Signed-off-by: Haiyang Zhang 
Acked-by: Stephen Hemminger 
Acked-by: Dexuan Cui 
Signed-off-by: Paolo Abeni 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: Fix race of register_netdevice_notifier and VF register

2023-12-03T06:31:24+00:00

commit 85520856466ed6bc3b1ccb013cddac70ceb437db upstream.

If VF NIC is registered earlier, NETDEV_REGISTER event is replayed,
but NETDEV_POST_INIT is not.

Move register_netdevice_notifier() earlier, so the call back
function is set before probing.

Cc: stable@vger.kernel.org
Fixes: e04e7a7bbd4b ("hv_netvsc: Fix a deadlock by getting rtnl lock earlier in netvsc_probe()")
Reported-by: Dexuan Cui 
Signed-off-by: Haiyang Zhang 
Reviewed-by: Wojciech Drewek 
Reviewed-by: Dexuan Cui 
Signed-off-by: Paolo Abeni 
Signed-off-by: Greg Kroah-Hartman