Add tests that validate vsock sockets are resilient to deleting
namespaces. The vsock sockets should still function normally.
The function check_ns_delete_doesnt_break_connection() is added to
re-use the step-by-step logic of 1) setup connections, 2) delete ns,
3) check that the connections are still ok.
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-12-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add tests to validate namespace correctness using vsock_test and socat.
The vsock_test tool is used to validate expected success tests, but
socat is used for expected failure tests. socat is used to ensure that
connections are rejected outright instead of failing due to some other
socket behavior (as tested in vsock_test). Additionally, socat is
already required for tunneling TCP traffic from vsock_test. Using only
one of the vsock_test tests like 'test_stream_client_close_client' would
have yielded a similar result, but doing so wouldn't remove the socat
dependency.
Additionally, check for the dependency socat. socat needs special
handling beyond just checking if it is on the path because it must be
compiled with support for both vsock and unix. The function
check_socat() checks that this support exists.
Add more padding to test name printf strings because the tests added in
this patch would otherwise overflow.
Add vm_dmesg_* helpers to encapsulate checking dmesg
for oops and warnings.
Add ability to pass extra args to host-side vsock_test so that tests
that cause false positives may be skipped with arg --skip.
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-11-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add tests to verify CID collision rules across different vsock namespace
modes.
1. Two VMs with the same CID cannot start in different global namespaces
(ns_global_same_cid_fails)
2. Two VMs with the same CID can start in different local namespaces
(ns_local_same_cid_ok)
3. VMs with the same CID can coexist when one is in a global namespace
and another is in a local namespace (ns_global_local_same_cid_ok and
ns_local_global_same_cid_ok)
The tests ns_global_local_same_cid_ok and ns_local_global_same_cid_ok
make sure that ordering does not matter.
The tests use a shared helper function namespaces_can_boot_same_cid()
that attempts to start two VMs with identical CIDs in the specified
namespaces and verifies whether VM initialization failed or succeeded.
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-10-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add tests for the /proc/sys/net/vsock/{ns_mode,child_ns_mode}
interfaces. Namely, that they accept/report "global" and "local" strings
and enforce their access policies.
Start a convention of commenting the test name over the test
description. Add test name comments over test descriptions that existed
before this convention.
Add a check_netns() function that checks if the test requires namespaces
and if the current kernel supports namespaces. Skip tests that require
namespaces if the system does not have namespace support.
This patch is the first to add tests that do *not* re-use the same
shared VM. For that reason, it adds a run_ns_tests() function to run
these tests and filter out the shared VM tests.
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-9-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Replace /proc/net parsing with ss(8) for detecting listening sockets in
wait_for_listener() functions and add support for TCP, VSOCK, and Unix
socket protocols.
The previous implementation parsed /proc/net/tcp using awk to detect
listening sockets, but this approach could not support vsock because
vsock does not export socket information to /proc/net/.
Instead, use ss so that we can detect listeners on tcp, vsock, and unix.
The protocol parameter is now required for all wait_for_listener family
functions (wait_for_listener, vm_wait_for_listener,
host_wait_for_listener) to explicitly specify which socket type to wait
for.
ss is added to the dependency check in check_deps().
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-8-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
These functions are reused by the VM tests to collect and compare dmesg
warnings and oops counts. The future VM-specific tests use them heavily.
This patches relies on vm_ssh() already supporting namespaces.
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-7-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add namespace support to vm management, ssh helpers, and vsock_test
wrapper functions. This enables running VMs and test helpers in specific
namespaces, which is required for upcoming namespace isolation tests.
The functions still work correctly within the init ns, though the caller
must now pass "init_ns" explicitly.
No functional changes for existing tests. All have been updated to pass
"init_ns" explicitly.
Affected functions (such as vm_start() and vm_ssh()) now wrap their
commands with 'ip netns exec' when executing commands in non-init
namespaces.
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-6-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add functions for initializing namespaces with the different vsock NS
modes. Callers can use add_namespaces() and del_namespaces() to create
namespaces global0, global1, local0, and local1.
The add_namespaces() function initializes global0, local0, etc... with
their respective vsock NS mode by toggling child_ns_mode before creating
the namespace.
Remove namespaces upon exiting the program in cleanup(). This is
unlikely to be needed for a healthy run, but it is useful for tests that
are manually killed mid-test.
This patch is in preparation for later namespace tests.
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-5-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Increase the timeout from 300s to 1200s. On a modern bare metal server
my last run showed the new set of tests taking ~400s. Multiply by an
(arbitrary) factor of three to account for slower/nested runners.
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-4-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add netns support to loopback and vhost. Keep netns disabled for
virtio-vsock, but add necessary changes to comply with common API
updates.
This is the patch in the series when vhost-vsock namespaces actually
come online.
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-3-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Associate reply packets with the sending socket. When vsock must reply
with an RST packet and there exists a sending socket (e.g., for
loopback), setting the skb owner to the socket correctly handles
reference counting between the skb and sk (i.e., the sk stays alive
until the skb is freed).
This allows the net namespace to be used for socket lookups for the
duration of the reply skb's lifetime, preventing race conditions between
the namespace lifecycle and vsock socket search using the namespace
pointer.
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-2-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add netns logic to vsock core. Additionally, modify transport hook
prototypes to be used by later transport-specific patches (e.g.,
*_seqpacket_allow()).
Namespaces are supported primarily by changing socket lookup functions
(e.g., vsock_find_connected_socket()) to take into account the socket
namespace and the namespace mode before considering a candidate socket a
"match".
This patch also introduces the sysctl /proc/sys/net/vsock/ns_mode to
report the mode and /proc/sys/net/vsock/child_ns_mode to set the mode
for new namespaces.
Add netns functionality (initialization, passing to transports, procfs,
etc...) to the af_vsock socket layer. Later patches that add netns
support to transports depend on this patch.
This patch changes the allocation of random ports for connectible vsocks
in order to avoid leaking the random port range starting point to other
namespaces.
dgram_allow(), stream_allow(), and seqpacket_allow() callbacks are
modified to take a vsk in order to perform logic on namespace modes. In
future patches, the net will also be used for socket
lookups in these functions.
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Link: https://patch.msgid.link/20260121-vsock-vmtest-v16-1-2859a7512097@meta.com
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
On 64bit arches, struct u64_stats_sync is empty and provides no help
against load/store tearing. Convert to u64_stats_t to ensure atomic
operations.
Note that does not mean the code is now tear-free: there're u32 counters
unprotected by u64_stats or anything else.
Signed-off-by: David Yang <mmyangfl@gmail.com>
Link: https://patch.msgid.link/20260123164841.2890054-1-mmyangfl@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
On 64bit arches, struct u64_stats_sync is empty and provides no help
against load/store tearing. Convert to u64_stats_t to ensure atomic
operations.
Signed-off-by: David Yang <mmyangfl@gmail.com>
Link: https://patch.msgid.link/20260123211101.2929547-1-mmyangfl@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The __exit__ method receives ex_type as the exception class when an
exception occurs. The previous code used implicit boolean evaluation:
terminate = self.terminate or (self._exit_wait and ex_type)
^^^^^^^^^^^
In Python, the and operator can be used with non-boolean values, but it
does not always return a boolean result.
This is probably not what we want, because 'self._exit_wait and ex_type'
could return the actual ex_type value (the exception class) rather than
a boolean True when an exception occurs.
Use explicit `ex_type is not None` check to properly evaluate whether
an exception occurred, returning a boolean result.
Reviewed-by: Nimrod Oren <noren@nvidia.com>
Signed-off-by: Gal Pressman <gal@nvidia.com>
Link: https://patch.msgid.link/20260125105524.773993-1-gal@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Minor simplification of the code by removing the optional size argument.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/d560ec66-848e-4290-818a-ce28f39de493@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The bits in register TxConfig used for chip identification aren't
sufficient for the number of upcoming chip versions. Therefore a register
is added with extended chip version information, for compatibility
purposes it's called TX_CONFIG_V2. First chip to use the extended chip
identification is RTL9151AS.
Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
[hkallweit1@gmail.com: add support for extended XID where XID is printed]
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/a3525b74-a1aa-43f6-8413-56615f6fa795@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
usbnet_get_link calls mii_link_ok if the device has a MII defined in
its usbnet struct and no check_connect function defined there. This is
true of these drivers, so their custom get_link functions which call
mii_link_ok are useless. Remove them in favor of usbnet_get_link.
Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Peter Korsgaard <peter@korsgaard.com>
Link: https://patch.msgid.link/20260124082217.82351-1-enelsonmoore@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The smsc95xx_ioctl function behaves identically to the
phy_do_ioctl_running function. Remove it and use the
phy_do_ioctl_running function directly instead.
Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260124080751.78488-1-enelsonmoore@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Justin Chen says:
====================
code clean up
Clean up and streamlined some code that is no longer needed due to
older HW support being dropped.
====================
Link: https://patch.msgid.link/20260122194949.1145107-1-justin.chen@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Streamline the bcmasp_probe early exit. As support for other
functionality is added(i.e. ptp), it is easier to keep track of early
exit cleanup when it is all in one place.
Signed-off-by: Justin Chen <justin.chen@broadcom.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://patch.msgid.link/20260122194949.1145107-3-justin.chen@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Removed wol_irq check. This was needed for brcm,asp-v2.0, which was
removed in previous commits.
Removed bcmasp_intf_ops. These function pointers were added to make
it easier to implement pseudo channels. These channels were removed
in newer versions of the hardware and were never implemented.
Signed-off-by: Justin Chen <justin.chen@broadcom.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://patch.msgid.link/20260122194949.1145107-2-justin.chen@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
On 64bit arches, struct u64_stats_sync is empty and provides no help
against load/store tearing. Convert to u64_stats_t to ensure atomic
operations.
Signed-off-by: David Yang <mmyangfl@gmail.com>
Link: https://patch.msgid.link/20260122185113.2760355-1-mmyangfl@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Tony Nguyen says:
====================
refactor IDPF resource access
Pavan Kumar Linga says:
Queue and vector resources for a given vport, are stored in the
idpf_vport structure. At the time of configuration, these
resources are accessed using vport pointer. Meaning, all the
config path functions are tied to the default queue and vector
resources of the vport.
There are use cases which can make use of config path functions
to configure queue and vector resources that are not tied to any
vport. One such use case is PTP secondary mailbox creation
(it would be in a followup series). To configure queue and interrupt
resources for such cases, we can make use of the existing config
infrastructure by passing the necessary queue and vector resources info.
To achieve this, group the existing queue and vector resources into
default resource group and refactor the code to pass the resource
pointer to the config path functions.
This series also includes patches which generalizes the send virtchnl
message APIs and mailbox API that are necessary for the implementation
of PTP secondary mailbox.
* '200GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/next-queue:
idpf: generalize mailbox API
idpf: avoid calling get_rx_ptypes for each vport
idpf: generalize send virtchnl message API
idpf: remove vport pointer from queue sets
idpf: add rss_data field to RSS function parameters
idpf: reshuffle idpf_vport struct members to avoid holes
idpf: move some iterator declarations inside for loops
idpf: move queue resources to idpf_q_vec_rsrc structure
idpf: introduce idpf_q_vec_rsrc struct and move vector resources to it
idpf: introduce local idpf structure to store virtchnl queue chunks
====================
Link: https://patch.msgid.link/20260122223601.2208759-1-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
SR_WR_REG and SR_WR_REGS may be confused at a cursory glance. Rename
them to be more easily differentiated to prevent this.
Suggested-by: Andrew Lunn <andrew+netdev@lunn.ch>
Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Peter Korsgaard <peter@korsgaard.com>
Link: https://patch.msgid.link/20260123080409.64165-1-enelsonmoore@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The driver hardcodes the number 6 as the number of bytes to write to
the SR_PAR register, which stores the MAC address. Use ETH_ALEN instead
to make the code clearer.
Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Peter Korsgaard <peter@korsgaard.com>
Link: https://patch.msgid.link/20260123070645.56434-1-enelsonmoore@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Petr Machata says:
====================
net: neighbour: Notify changes atomically
Andy Roulin and Francesco Ruggeri have apparently independently both hit an
issue with the current neighbor notification scheme. Francesco reported the
issue in [1]. In a response[2] to that report, Andy said:
neigh_update sends a rtnl notification if an update, e.g.,
nud_state change, was done but there is no guarantee of
ordering of the rtnl notifications. Consider the following
scenario:
userspace thread kernel thread
================ =============
neigh_update
write_lock_bh(n->lock)
n->nud_state = STALE
write_unlock_bh(n->lock)
neigh_notify
neigh_fill_info
read_lock_bh(n->lock)
ndm->nud_state = STALE
read_unlock_bh(n->lock)
-------------------------->
neigh:update
write_lock_bh(n->lock)
n->nud_state = REACHABLE
write_unlock_bh(n->lock)
neigh_notify
neigh_fill_info
read_lock_bh(n->lock)
ndm->nud_state = REACHABLE
read_unlock_bh(n->lock)
rtnl_nofify
RTNL REACHABLE sent
<--------
rtnl_notify
RTNL STALE sent
In this scenario, the kernel neigh is updated first to STALE and
then REACHABLE but the netlink notifications are sent out of order,
first REACHABLE and then STALE.
The solution presented in [2] was to extend the critical region to include
both the call to neigh_fill_info(), as well as rtnl_notify(). Then we have
a guarantee that whatever state was captured by neigh_fill_info(), will be
sent right away. The above scenario can thus not happen.
This is how this patchset begins: patches #1 and #2 add helper duals to
neigh_fill_info() and __neigh_notify() such that the __-prefixed function
assumes the neighbor lock is held, and the unprefixed one is a thin wrapper
that manages locking. This extends locking further than Andy's patch, but
makes for a clear code and supports the following part.
At that point, the original race is gone. But what can happen is the
following race, where the notification does not reflect the change that was
made:
userspace thread kernel thread
================ =============
neigh_update
write_lock_bh(n->lock)
n->nud_state = STALE
write_unlock_bh(n->lock)
-------------------------->
neigh:update
write_lock_bh(n->lock)
n->nud_state = REACHABLE
write_unlock_bh(n->lock)
neigh_notify
read_lock_bh(n->lock)
__neigh_fill_info
ndm->nud_state = REACHABLE
rtnl_notify
read_unlock_bh(n->lock)
RTNL REACHABLE sent
<--------
neigh_notify
read_lock_bh(n->lock)
__neigh_fill_info
ndm->nud_state = REACHABLE
rtnl_notify
read_unlock_bh(n->lock)
RTNL REACHABLE sent again
Here, even though neigh_update() made a change to STALE, it later sends a
notification with a NUD of REACHABLE. The obvious solution to fix this race
is to move the notifier to the same critical section that actually makes
the change.
Sending a notification in fact involves two things: invoking the internal
notifier chain, and sending the netlink notification. The overall approach
in this patchset is to move the netlink notification to the critical
section of the change, while keeping the internal notifier intact. Since
the motion is not obviously correct, the patchset presents the change in
series of incremental steps with discussion in commit messages. Please see
details in the patches themselves.
Reproducer
==========
To consistently reproduce, I injected an mdelay before the rtnl_notify()
call. Since only one thread should delay, a bit of instrumentation was
needed to see where the call originates. The mdelay was then only issued on
the call stack rooted in the RTNL request.
Then the general idea is to issue an "ip neigh replace" to mark a neighbor
entry as failed. In parallel to that, inject an ARP burst that validates
the entry. This is all observed with an "ip monitor neigh", where one can
see either a REACHABLE->FAILED transition, or FAILED->REACHABLE, while the
actual state at the end of the sequence is always REACHABLE.
With the patchset, only FAILED->REACHABLE is ever observed in the monitor.
Alternatives
============
Another approach to solving the issue would be to have a per-neighbor queue
of notification digests, each with a set of fields necessary for formatting
a notification. In pseudocode, a neighbor update would look something like
this:
neighbor_update:
- lock
- do update
- allocate notification digest, fill partially, mark not-committed
- unlock
- critical-section-breaking stuff (probes, ARP Q, etc.)
- lock
- fill in missing details to the digest (notably neigh->probes)
- mark the digest as committed
- while (front of the digest queue is committed)
- pop it, convert to notifier, send the notification
- unlock
This adds more complexity and would imply more changes to the code, which
is why I think the approach presented in this patchset is better. But it
would allow us to retain the overall structure of the code while giving us
accurate notifications.
A third approach would be to consider the second race not very serious and
be OK with seeing a notification that does not reflect the change that
prompted it. Then a two-patch prefix of this patchset would be all that is
needed.
[1]: https://lore.kernel.org/20220606230107.D70B55EC0B30@us226.sjc.aristanetworks.com
[2]: https://lore.kernel.org/ed6768c1-80b8-aee2-e545-b51661d49336@nvidia.com
====================
Link: https://patch.msgid.link/cover.1769012464.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Similarly to the issue from the previous patch, neigh_timer_handler() also
updates the neighbor separately from formatting and sending the netlink
notification message. We have not seen reports to the effect of this
causing trouble, but in theory, the same sort of issues could have come up:
neigh_timer_handler() would make changes as necessary, but before
formatting and sending a notification, is interrupted before sending by
another thread, which makes a parallel change and sends its own message.
The message send that is prompted by an earlier change thus contains
information that does not reflect the change having been made.
To solve this, the netlink notification needs to be in the same critical
section that updates the neighbor. The critical section is ended by the
neigh_probe() call which drops the lock before calling solicit. Stretching
the critical section over the solicit call is problematic, because that can
then involved all sorts of forwarding callbacks. Therefore, like in the
previous patch, split the netlink notification away from the internal one
and move it ahead of the probe call.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/e440118511cbdbe1d88eb0d71c9047116feb96e0.1769012464.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As noted in a previous patch, one race remains in the current code. A
kernel thread might interrupt a userspace thread after the change is done,
but before formatting and sending the message. Then what we would see is
two messages with the same contents:
userspace thread kernel thread
================ =============
neigh_update
write_lock_bh(n->lock)
n->nud_state = STALE
write_unlock_bh(n->lock)
-------------------------->
neigh:update
write_lock_bh(n->lock)
n->nud_state = REACHABLE
write_unlock_bh(n->lock)
neigh_notify
read_lock_bh(n->lock)
__neigh_fill_info
ndm->nud_state = REACHABLE
rtnl_notify
read_unlock_bh(n->lock)
RTNL REACHABLE sent
<--------
neigh_notify
read_lock_bh(n->lock)
__neigh_fill_info
ndm->nud_state = REACHABLE
rtnl_notify
read_unlock_bh(n->lock)
RTNL REACHABLE sent again
The solution is to send the netlink message inside the critical section
where the neighbor is changed, so that it reflects the notified-upon
neighbor state.
To that end, in __neigh_update(), move the current neigh_notify() call up
to said critical section, and convert it to __neigh_notify(), because the
lock is held. This motion crosses calls to neigh_update_managed_list(),
neigh_update_gc_list() and neigh_update_process_arp_queue(), all of which
potentially unlock and give an opportunity for the above race.
This also crosses a call to neigh_update_process_arp_queue() which calls
neigh->output(), which might be neigh_resolve_output() calls
neigh_event_send() calls neigh_event_send_probe() calls
__neigh_event_send() calls neigh_probe(), which touches neigh->probes,
an update which will now not be visible in the notification.
However, there is indication that there is no promise that these changes
will be accurately projected to notifications: fib6_table_lookup()
indirectly calls route.c's find_match() calls rt6_probe(), which looks up a
neighbor and call __neigh_set_probe_once(), which sets neigh->probes to 0,
but neither this nor the caller seems to send a notification.
Additionally, the neighbor object that the neigh_probe() mentioned above is
called on, might be the alternative neighbor looked up for the ARP queue
packet destination. If that is the case, the changed value of n1->probes is
not notified anywhere.
So at least in some circumstances, the reported number of probes needs to
be assumed to change without notification.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/ceb44995498eb52375cb2d46c3245bdb9e74b355.1769012464.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The netlink message needs to be send inside the critical section where the
neighbor is changed, so that it reflects the notified-upon neighbor state.
On the other hand, there is no such need in case of notifier chain: the
listeners do not assume lock, and often in fact just schedule a delayed
work to act on the neighbor later. At least one in fact also takes the
neighbor lock.
This requires that the netlink notification be done before the internal
notifier chain message is sent. That is safe to do, because the current
listeners, as well as __neigh_notify(), only read the updated neighbor
fields, and never modify them. (Apart from locking.)
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/f3ef74d5460f14c4d102b8a5857d4a6624da9a5a.1769012464.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The obvious idea behind the helper is to keep together the two bits that
should be done either both or neither: the internal notifier chain message,
and the netlink notification.
To make sure that the notification sent reflects the change being made, the
netlink message needs to be send inside the critical section where the
neighbor is changed. But for the notifier chain, there is no such need: the
listeners do not assume lock, and often in fact just schedule a delayed
work to act on the neighbor later. At least one in fact also takes the
neighbor lock. Therefore these two items have each different locking needs.
Now we could unlock inside the helper, but I find that error prone, and the
fact that the notification is conditional in the first place does not help
to make the call site obvious.
So in this patch, the helper is instead removed and the body, which is just
these two calls, inlined. That way we can use each notifier independently.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/e65dce5882bc6f4aa2530b8a4877d0e003071a1a.1769012464.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ARP queue processing unlocks the neighbor lock, which can allow another
thread to asynchronously perform a neighbor update and send an out of order
notification. Therefore this needs to be done after the notification is
sent.
Move it just before the end of the critical section. Since
neigh_update_process_arp_queue() unlocks, it does not form a part of the
critical section anymore but it can benefit from the lock being taken. The
intention is to eventually do the RTNL notification before this call.
This motion crosses a call to neigh_update_is_router(), which should not
influence processing of the ARP queue.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/9ea7159e71430ebdc837ebcc880a76b7e82e52a4.1769012464.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In order to make manipulation with this bit of code clearer, extract it
to a helper function, neigh_update_process_arp_queue().
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/8b0fa0abe2cf0e24484903f5436fe0ac64163057.1769012464.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Andy Roulin has described an issue with the current neighbor notification
scheme as follows. This was also presented publicly at the link below.
neigh_update sends a rtnl notification if an update, e.g.,
nud_state change, was done but there is no guarantee of
ordering of the rtnl notifications. Consider the following
scenario:
userspace thread kernel thread
================ =============
neigh_update
write_lock_bh(n->lock)
n->nud_state = STALE
write_unlock_bh(n->lock)
neigh_notify
neigh_fill_info
read_lock_bh(n->lock)
ndm->nud_state = STALE
read_unlock_bh(n->lock)
-------------------------->
neigh:update
write_lock_bh(n->lock)
n->nud_state = REACHABLE
write_unlock_bh(n->lock)
neigh_notify
neigh_fill_info
read_lock_bh(n->lock)
ndm->nud_state = REACHABLE
read_unlock_bh(n->lock)
rtnl_nofify
RTNL REACHABLE sent
<--------
rtnl_notify
RTNL STALE sent
In this scenario, the kernel neigh is updated first to STALE and
then REACHABLE but the netlink notifications are sent out of order,
first REACHABLE and then STALE.
The solution is to send the netlink message inside the same critical
section that formats the message. That way both the contents and ordering
of the message reflect the same state, and we cannot see the abovementioned
out-of-order delivery.
Even with this patch, a remaining issue that the contents of the message
may not reflect the changes made to the neighbor. A kernel thread might
still interrupt a userspace thread after the change is done, but before
formatting and sending the message. Then what we would see is two messages
with the same contents. The following patches will attempt to address that
issue.
To support those future patches, convert __neigh_notify() to a helper that
assumes that the neighbor lock is already taken by having it call
__neigh_fill_info() instead of neigh_fill_info(). Add a new helper,
neigh_notify(), which takes the lock before calling __neigh_notify().
Migrate all callers to use the latter.
Link: https://lore.kernel.org/netdev/ed6768c1-80b8-aee2-e545-b51661d49336@nvidia.com/
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/4b4368dcc5f5a7e407009cb6c36b69cfb5282864.1769012464.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The netlink message needs to be formatted and sent inside the critical
section where the neighbor is changed, so that it reflects the
notified-upon neighbor state. Because it will happen inside an already
existing critical section, it has to assume that the neighbor lock is held.
Add a helper __neigh_fill_info(), which is like neigh_fill_info(), but
makes this assumption. Convert neigh_fill_info() to a wrapper around this
new helper.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/7ec20113d5d809200e3534d3ed8f0004514914b8.1769012464.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
idev->mr_maxdelay is read and written locklessly,
add READ_ONCE()/WRITE_ONCE() annotations.
While we are at it, make this field an u32.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20260122172247.2429403-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ipvlan_ht_addr_lookup() is called four times and not inlined.
Split it to ipvlan_ht_addr_lookup6() and ipvlan_ht_addr_lookup4()
and rework ipvlan_addr_lookup() to call these helpers once,
so that they are (auto)inlined.
After this change, ipvlan_addr_lookup() is faster, and we save
350 bytes of text on x86_64.
$ scripts/bloat-o-meter -t vmlinux.old vmlinux.new
add/remove: 0/2 grow/shrink: 1/0 up/down: 123/-473 (-350)
Function old new delta
ipvlan_addr_lookup 467 590 +123
__pfx_ipvlan_ht_addr_lookup 16 - -16
ipvlan_ht_addr_lookup 457 - -457
Total: Before=22571833, After=22571483, chg -0.00%
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260122165049.2366985-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
NETDEV_RSS_KEY_LEN has been set to 52 bytes in 2014, until now.
Jakub suggested we bump the size to 128 bytes or more.
Some drivers (like idpf) were already working around the core limit.
Since this change might cause some issues in admin scripts,
bump it directly to 256 in one go.
tjbp26:~# cat /proc/sys/net/core/netdev_rss_key | wc -c
768
tjbp26:~# ethtool -x eth1
RX flow hash indirection table for eth1 with 32 RX ring(s):
...
RSS hash key:
fe:16:5b:2f:93:85:c2:c9:c1:ef:bd:60:c6:e0:2b:99:4d:bf:b7:14:c8:1e:8d:cb:31:17:51:da:55:eb:91:d9:9e:f9:89:9b:44:a1:dc:08:72:3a:b3:d6:31:86:9a:fe:02:3a:0d:eb:a1:7c:f5:a3:51:3b:08:56:c9:3f:71:69:01:ba:70:38
RSS hash function:
toeplitz: on
xor: off
crc32: off
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/netdev/20260122075206.504ec591@kernel.org/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260122190349.2771064-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Eric Dumazet says:
====================
net: few critical helpers are inlined again
Recent devmem additions increased stack depth. Some helpers
that were inlined in the past are now out-of-line.
====================
Link: https://patch.msgid.link/20260122045720.1221017-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
1) Inline this small helper to reduce code size and decrease cpu costs.
2) Constify its argument.
3) Move it to include/net/netmem.h, as a prereq for the following patch.
$ scripts/bloat-o-meter -t vmlinux.2 vmlinux.3
add/remove: 0/2 grow/shrink: 0/4 up/down: 0/-158 (-158)
Function old new delta
validate_xmit_skb 866 857 -9
__pfx_net_is_devmem_iov 16 - -16
net_is_devmem_iov 22 - -22
get_netmem 152 130 -22
put_netmem 140 114 -26
tcp_recvmsg_locked 3860 3797 -63
Total: Before=22566015, After=22565857, chg -0.00%
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260122045720.1221017-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
clang is not inlining skb_frag_unref() and __skb_frag_unref()
in gro fast path.
It also does not inline gro_try_pull_from_frag0().
Using __always_inline fixes this issue, makes the
kernel faster _and_ smaller.
Also change __skb_frag_ref(), skb_frag_ref() and skb_page_unref()
to let them inlined for the last patch in this series.
$ scripts/bloat-o-meter -t vmlinux.0 vmlinux.1
add/remove: 2/6 grow/shrink: 1/2 up/down: 218/-511 (-293)
Function old new delta
gro_pull_from_frag0 - 188 +188
__pfx_gro_pull_from_frag0 - 16 +16
skb_shift 1125 1139 +14
__pfx_skb_frag_unref 16 - -16
__pfx_gro_try_pull_from_frag0 16 - -16
__pfx___skb_frag_unref 16 - -16
__skb_frag_unref 36 - -36
skb_frag_unref 59 - -59
dev_gro_receive 1608 1514 -94
napi_gro_frags 892 771 -121
gro_try_pull_from_frag0 153 - -153
Total: Before=22566192, After=22565899, chg -0.00%
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260122045720.1221017-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
David Yang says:
====================
u64_stats: Introduce u64_stats_copy()
On 64bit arches, struct u64_stats_sync is empty and provides no help
against load/store tearing. memcpy() should not be considered atomic
against u64 values. Use u64_stats_copy() instead.
====================
Link: https://patch.msgid.link/20260120092137.2161162-1-mmyangfl@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
On 64bit arches, struct u64_stats_sync is empty and provides no help
against load/store tearing. memcpy() should not be considered atomic
against u64 values. Use u64_stats_copy() instead.
Signed-off-by: David Yang <mmyangfl@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260120092137.2161162-5-mmyangfl@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
On 64bit arches, struct u64_stats_sync is empty and provides no help
against load/store tearing. memcpy() should not be considered atomic
against u64 values. Use u64_stats_copy() instead.
Signed-off-by: David Yang <mmyangfl@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260120092137.2161162-4-mmyangfl@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
