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1,447,411 commits

Author SHA1 Message Date
Marek Vasut
bfb859a5cb dt-bindings: net: realtek,rtl82xx: Document realtek,*-ssc-enable property
Document support for spread spectrum clocking (SSC) on RTL8211F(D)(I)-CG,
RTL8211FS(I)(-VS)-CG, RTL8211FG(I)(-VS)-CG PHYs. Introduce DT properties
'realtek,clkout-ssc-enable', 'realtek,rxc-ssc-enable' and
'realtek,sysclk-ssc-enable' which control CLKOUT, RXC and SYSCLK
SSC spread spectrum clocking enablement on these signals. These
clock are not exposed via the clock API, therefore assigned-clock-sscs
property does not apply.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Marek Vasut <marek.vasut@mailbox.org>
Link: https://patch.msgid.link/20260405233008.148974-2-marek.vasut@mailbox.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 20:01:52 -07:00
Marek Vasut
4de7a8acd1 dt-bindings: net: realtek,rtl82xx: Keep property list sorted
Sort the documented properties alphabetically, no functional change.

Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Marek Vasut <marek.vasut@mailbox.org>
Link: https://patch.msgid.link/20260405233008.148974-1-marek.vasut@mailbox.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 20:01:52 -07:00
Jakub Kicinski
b02e3c4c80 Merge branch 'macsec-add-support-for-vlan-filtering-in-offload-mode'
Cosmin Ratiu says:

====================
macsec: Add support for VLAN filtering in offload mode

This short series adds support for VLANs in MACsec devices when offload
mode is enabled. This allows VLAN netdevs on top of MACsec netdevs to
function, which accidentally used to be the case in the past, but was
broken. This series adds back proper support.

As part of this, the existing nsim-only MACsec offload tests were
translated to Python so they can run against real HW and new
traffic-based tests were added for VLAN filter propagation, since
there's currently no uAPI to check VLAN filters.
====================

Link: https://patch.msgid.link/20260408115240.1636047-1-cratiu@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 19:38:45 -07:00
Cosmin Ratiu
a363b1c8be macsec: Support VLAN-filtering lower devices
VLAN-filtering is done through two netdev features
(NETIF_F_HW_VLAN_CTAG_FILTER and NETIF_F_HW_VLAN_STAG_FILTER) and two
netdev ops (ndo_vlan_rx_add_vid and ndo_vlan_rx_kill_vid).

Implement these and advertise the features if the lower device supports
them. This allows proper VLAN filtering to work on top of MACsec
devices, when the lower device is capable of VLAN filtering.
As a concrete example, having this chain of interfaces now works:
vlan_filtering_capable_dev(1) -> macsec_dev(2) -> macsec_vlan_dev(3)

Before the mentioned commit this used to accidentally work because the
MACsec device (and thus the lower device) was put in promiscuous mode
and the VLAN filter was not used. But after commit [1] correctly made
the macsec driver expose the IFF_UNICAST_FLT flag, promiscuous mode was
no longer used and VLAN filters on dev 1 kicked in. Without support in
dev 2 for propagating VLAN filters down, the register_vlan_dev ->
vlan_vid_add -> __vlan_vid_add -> vlan_add_rx_filter_info call from dev
3 is silently eaten (because vlan_hw_filter_capable returns false and
vlan_add_rx_filter_info silently succeeds).

For MACsec, VLAN filters are only relevant for offload, otherwise
the VLANs are encrypted and the lower devices don't care about them. So
VLAN filters are only passed on to lower devices in offload mode.
Flipping between offload modes now needs to offload/unoffload the
filters with vlan_{get,drop}_rx_*_filter_info().

To avoid the back-and-forth filter updating during rollback, the setting
of macsec->offload is moved after the add/del secy ops. This is safe
since none of the code called from those requires macsec->offload.

In case adding the filters fails, the added ones are rolled back and an
error is returned to the operation toggling the offload state.

Fixes: 0349659fd7 ("macsec: set IFF_UNICAST_FLT priv flag")
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20260408115240.1636047-5-cratiu@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 19:38:42 -07:00
Cosmin Ratiu
26555673bc selftests: Add MACsec VLAN propagation traffic test
Add VLAN filter propagation tests through offloaded MACsec devices via
actual traffic.

The tests create MACsec tunnels with matching SAs on both endpoints,
stack VLANs on top, and verify connectivity with ping. Covered:
- Offloaded MACsec with VLAN (filters propagate to HW)
- Software MACsec with VLAN (no HW filter propagation)
- Offload on/off toggle and verifying traffic still works

On netdevsim this makes use of the VLAN filter debugfs file to actually
validate that filters are applied/removed correctly.
On real hardware the traffic should validate actual VLAN filter
propagation.

Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20260408115240.1636047-4-cratiu@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 19:38:42 -07:00
Cosmin Ratiu
c89f194b6b nsim: Add support for VLAN filters
Add support for storing the list of VLANs in nsim devices, together with
ops for adding/removing them and a debug file to show them.

This will be used in upcoming tests.

Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20260408115240.1636047-3-cratiu@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 19:38:42 -07:00
Cosmin Ratiu
e1ab601bb2 selftests: Migrate nsim-only MACsec tests to Python
Move MACsec offload API and ethtool feature tests from
tools/testing/selftests/drivers/net/netdevsim/macsec-offload.sh to
tools/testing/selftests/drivers/net/macsec.py using the NetDrvEnv
framework so tests can run against both netdevsim (default) and real
hardware (NETIF=ethX). As some real hardware requires MACsec to use
encryption, add that to the tests.

Netdevsim-specific limit checks (max SecY, max RX SC) were moved into
separate test cases to avoid failures on real hardware.

Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20260408115240.1636047-2-cratiu@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 19:38:41 -07:00
Paolo Abeni
8e6405f821 ipv6: move IFA_F_PERMANENT percpu allocation in process scope
Observed at boot time:

 CPU: 43 UID: 0 PID: 3595 Comm: (t-daemon) Not tainted 6.12.0 #1
 Call Trace:
  <TASK>
  dump_stack_lvl+0x4e/0x70
  pcpu_alloc_noprof.cold+0x1f/0x4b
  fib_nh_common_init+0x4c/0x110
  fib6_nh_init+0x387/0x740
  ip6_route_info_create+0x46d/0x640
  addrconf_f6i_alloc+0x13b/0x180
  addrconf_permanent_addr+0xd0/0x220
  addrconf_notify+0x93/0x540
  notifier_call_chain+0x5a/0xd0
  __dev_notify_flags+0x5c/0xf0
  dev_change_flags+0x54/0x70
  do_setlink+0x36c/0xce0
  rtnl_setlink+0x11f/0x1d0
  rtnetlink_rcv_msg+0x142/0x3f0
  netlink_rcv_skb+0x50/0x100
  netlink_unicast+0x242/0x390
  netlink_sendmsg+0x21b/0x470
  __sys_sendto+0x1dc/0x1f0
  __x64_sys_sendto+0x24/0x30
  do_syscall_64+0x7d/0x160
  entry_SYSCALL_64_after_hwframe+0x76/0x7e
 RIP: 0033:0x7f5c3852f127
 Code: 0c 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 80 3d 85 ef 0c 00 00 41 89 ca 74 10 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 71 c3 55 48 83 ec 30 44 89 4c 24 2c 4c 89 44
 RSP: 002b:00007ffe86caf4c8 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
 RAX: ffffffffffffffda RBX: 0000556c5cd93210 RCX: 00007f5c3852f127
 RDX: 0000000000000020 RSI: 0000556c5cd938b0 RDI: 0000000000000003
 RBP: 00007ffe86caf5a0 R08: 00007ffe86caf4e0 R09: 0000000000000080
 R10: 0000000000000000 R11: 0000000000000202 R12: 0000556c5cd932d0
 R13: 00000000021d05d1 R14: 00000000021d05d1 R15: 0000000000000001

IFA_F_PERMANENT addresses require the allocation of a bunch of percpu
pointers, currently in atomic scope.

Similar to commit 51454ea42c ("ipv6: fix locking issues with loops
over idev->addr_list"), move fixup_permanent_addr() outside the
&idev->lock scope, and do the allocations with GFP_KERNEL. With such
change fixup_permanent_addr() is invoked with the BH enabled, and the
ifp lock acquired there needs the BH variant.

Note that we don't need to acquire a reference to the permanent
addresses before releasing the mentioned write lock, because
addrconf_permanent_addr() runs under RTNL and ifa removal always happens
under RTNL, too.

Also the PERMANENT flag is constant in the relevant scope, as it can be
cleared only by inet6_addr_modify() under the RTNL lock.

Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Link: https://patch.msgid.link/46a7a030727e236af2dc7752994cd4f04f4a91d2.1775658924.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 19:32:45 -07:00
David Carlier
9addea5d44 net: use get_random_u{16,32,64}() where appropriate
Use the typed random integer helpers instead of
get_random_bytes() when filling a single integer variable.
The helpers return the value directly, require no pointer
or size argument, and better express intent.

Skipped sites writing into __be16 (netdevsim) and __le64
(ceph) fields where a direct assignment would trigger
sparse endianness warnings.

Signed-off-by: David Carlier <devnexen@gmail.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260407150758.5889-1-devnexen@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 19:27:43 -07:00
Zhang Yi
981fcc5674 jbd2: fix deadlock in jbd2_journal_cancel_revoke()
Commit f76d4c28a4 ("fs/jbd2: use sleeping version of
__find_get_block()") changed jbd2_journal_cancel_revoke() to use
__find_get_block_nonatomic() which holds the folio lock instead of
i_private_lock. This breaks the lock ordering (folio -> buffer) and
causes an ABBA deadlock when the filesystem blocksize < pagesize:

     T1                                T2
ext4_mkdir()
 ext4_init_new_dir()
  ext4_append()
   ext4_getblk()
    lock_buffer()    <- A
                                   sync_blockdev()
                                    blkdev_writepages()
                                     writeback_iter()
                                      writeback_get_folio()
                                       folio_lock()   <- B
     ext4_journal_get_create_access()
      jbd2_journal_cancel_revoke()
       __find_get_block_nonatomic()
        folio_lock()  <- B
                                     block_write_full_folio()
                                      lock_buffer()   <- A

This can occasionally cause generic/013 to hang.

Fix by only calling __find_get_block_nonatomic() when the passed
buffer_head doesn't belong to the bdev, which is the only case that we
need to look up its bdev alias. Otherwise, the lookup is redundant since
the found buffer_head is equal to the one we passed in.

Fixes: f76d4c28a4 ("fs/jbd2: use sleeping version of __find_get_block()")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20260409114204.917154-1-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
2026-04-09 22:09:39 -04:00
Sohei Koyama
77d0595193 ext4: fix missing brelse() in ext4_xattr_inode_dec_ref_all()
The commit c8e008b604 ("ext4: ignore xattrs past end")
introduced a refcount leak in when block_csum is false.

ext4_xattr_inode_dec_ref_all() calls ext4_get_inode_loc() to
get iloc.bh, but never releases it with brelse().

Fixes: c8e008b604 ("ext4: ignore xattrs past end")
Signed-off-by: Sohei Koyama <skoyama@ddn.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Cc: stable@vger.kernel.org
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Baokun Li <libaokun@linux.alibaba.com>
Link: https://patch.msgid.link/20260406074830.8480-1-skoyama@ddn.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 22:06:12 -04:00
Ye Bin
22f53f08d9 ext4: fix possible null-ptr-deref in mbt_kunit_exit()
There's issue as follows:
    # test_new_blocks_simple: failed to initialize: -12
KASAN: null-ptr-deref in range [0x0000000000000638-0x000000000000063f]
Tainted: [E]=UNSIGNED_MODULE, [N]=TEST
RIP: 0010:mbt_kunit_exit+0x5e/0x3e0 [ext4_test]
Call Trace:
 <TASK>
 kunit_try_run_case_cleanup+0xbc/0x100 [kunit]
 kunit_generic_run_threadfn_adapter+0x89/0x100 [kunit]
 kthread+0x408/0x540
 ret_from_fork+0xa76/0xdf0
 ret_from_fork_asm+0x1a/0x30

If mbt_kunit_init() init testcase failed will lead to null-ptr-deref.
So add test if 'sb' is inited success in mbt_kunit_exit().

Fixes: 7c9fa399a3 ("ext4: add first unit test for ext4_mb_new_blocks_simple in mballoc")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20260330133035.287842-6-yebin@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 22:04:32 -04:00
Ye Bin
ca78c31af4 ext4: fix possible null-ptr-deref in extents_kunit_exit()
There's issue as follows:
KASAN: null-ptr-deref in range [0x00000000000002c0-0x00000000000002c7]
Tainted: [E]=UNSIGNED_MODULE, [N]=TEST
RIP: 0010:extents_kunit_exit+0x2e/0xc0 [ext4_test]
Call Trace:
 <TASK>
 kunit_try_run_case_cleanup+0xbc/0x100 [kunit]
 kunit_generic_run_threadfn_adapter+0x89/0x100 [kunit]
 kthread+0x408/0x540
 ret_from_fork+0xa76/0xdf0
 ret_from_fork_asm+0x1a/0x30

Above issue happens as extents_kunit_init() init testcase failed.
So test if testcase is inited success.

Fixes: cb1e0c1d1f ("ext4: kunit tests for extent splitting and conversion")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://patch.msgid.link/20260330133035.287842-5-yebin@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 22:04:32 -04:00
Ye Bin
17f73c95d4 ext4: fix the error handling process in extents_kunit_init).
The error processing in extents_kunit_init() is improper, causing
resource leakage.
Reconstruct the error handling process to prevent potential resource
leaks

Fixes: cb1e0c1d1f ("ext4: kunit tests for extent splitting and conversion")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20260330133035.287842-4-yebin@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 22:04:32 -04:00
Ye Bin
f9c1f7647a ext4: call deactivate_super() in extents_kunit_exit()
Call deactivate_super() is called in extents_kunit_exit() to cleanup
the file system resource.

Fixes: cb1e0c1d1f ("ext4: kunit tests for extent splitting and conversion")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20260330133035.287842-3-yebin@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 22:04:32 -04:00
Ye Bin
5941a072d4 ext4: fix miss unlock 'sb->s_umount' in extents_kunit_init()
There's warning as follows when do ext4 kunit test:
WARNING: kunit_try_catch/15923 still has locks held!
7.0.0-rc3-next-20260309-00028-g73f965a1bbb1-dirty #281 Tainted: G            E    N
1 lock held by kunit_try_catch/15923:
 #0: ffff888139f860e0 (&type->s_umount_key#70/1){+.+.}-{4:4}, at: alloc_super.constprop.0+0x172/0xa90
Call Trace:
 <TASK>
 dump_stack_lvl+0x180/0x1b0
 debug_check_no_locks_held+0xc8/0xd0
 do_exit+0x1502/0x2b20
 kthread+0x3a9/0x540
 ret_from_fork+0xa76/0xdf0
 ret_from_fork_asm+0x1a/0x30

As sget() will return 'sb' which holds 's->s_umount' lock. However,
"extents-test" miss unlock this lock.
So unlock 's->s_umount' in the end of extents_kunit_init().

Fixes: cb1e0c1d1f ("ext4: kunit tests for extent splitting and conversion")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20260330133035.287842-2-yebin@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 22:04:32 -04:00
Deepanshu Kartikey
eceafc31ea ext4: fix bounds check in check_xattrs() to prevent out-of-bounds access
The bounds check for the next xattr entry in check_xattrs() uses
(void *)next >= end, which allows next to point within sizeof(u32)
bytes of end. On the next loop iteration, IS_LAST_ENTRY() reads 4
bytes via *(__u32 *)(entry), which can overrun the valid xattr region.

For example, if next lands at end - 1, the check passes since
next < end, but IS_LAST_ENTRY() reads 4 bytes starting at end - 1,
accessing 3 bytes beyond the valid region.

Fix this by changing the check to (void *)next + sizeof(u32) > end,
ensuring there is always enough space for the IS_LAST_ENTRY() read
on the subsequent iteration.

Fixes: 3478c83cf2 ("ext4: improve xattr consistency checking and error reporting")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20260224231429.31361-1-kartikey406@gmail.com/T/ [v1]
Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com>
Link: https://patch.msgid.link/20260328150038.349497-1-kartikey406@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 22:01:39 -04:00
Zhang Yi
3f60efd654 ext4: zero post-EOF partial block before appending write
In cases of appending write beyond EOF, ext4_zero_partial_blocks() is
called within ext4_*_write_end() to zero out the partial block beyond
EOF. This prevents exposing stale data that might be written through
mmap.

However, supporting only the regular buffered write path is
insufficient. It is also necessary to support the DAX path as well as
the upcoming iomap buffered write path. Therefore, move this operation
to ext4_write_checks().

In addition, this may introduce a race window in which a post-EOF
buffered write can race with an mmap write after the old EOF block has
been zeroed. As a result, the data in this block written by the
buffer-write and the data written by the mmap-write may be mixed.
However, this is safe because users should not rely on the result of the
race condition.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-14-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:52 -04:00
Zhang Yi
1ad0f42823 ext4: move pagecache_isize_extended() out of active handle
In ext4_alloc_file_blocks(), pagecache_isize_extended() is called under
an active handle and may also hold folio lock if the block size is
smaller than the folio size. This also breaks the "folio lock ->
transaction start" lock ordering for the upcoming iomap buffered I/O
path.

Therefore, move pagecache_isize_extended() outside of an active handle.
Additionally, it is unnecessary to update the file length during each
iteration of the allocation loop. Instead, update the file length only
to the position where the allocation is successful. Postpone updating
the inode size until after the allocation loop completes or is
interrupted due to an error.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-13-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:52 -04:00
Zhang Yi
116c0bdac2 ext4: remove ctime/mtime update from ext4_alloc_file_blocks()
The ctime and mtime update is already handled by file_modified() in
ext4_fallocate(), the caller of ext4_alloc_file_blocks(). So remove the
redundant calls to inode_set_ctime_current() and inode_set_mtime_to_ts()
in ext4_alloc_file_blocks().

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-12-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:52 -04:00
Zhang Yi
c3688d212f ext4: unify SYNC mode checks in fallocate paths
In the ext4 fallocate call chain, SYNC mode handling is inconsistent:
some places check the inode state, while others check the open file
descriptor state. Unify these checks by evaluating both conditions
to ensure consistent behavior across all fallocate operations.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-11-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:52 -04:00
Zhang Yi
7d81ec0246 ext4: ensure zeroed partial blocks are persisted in SYNC mode
In ext4_zero_range() and ext4_punch_hole(), when operating in SYNC mode
and zeroing a partial block, only data=journal modes guarantee that the
zeroed data is synchronously persisted after the operation completes.
For data=ordered/writeback mode and non-journal modes, this guarantee is
missing.

Introduce a partial_zero parameter to explicitly trigger writeback for
all scenarios where a partial block is zeroed, ensuring the zeroed data
is durably persisted.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20260327102939.1095257-10-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:52 -04:00
Zhang Yi
c4602a1d09 ext4: move zero partial block range functions out of active handle
Move ext4_block_zero_eof() and ext4_zero_partial_blocks() calls out of
the active handle context, making them independent operations, and also
add return value checks. This is safe because it still ensures data is
updated before metadata for data=ordered mode and data=journal mode
because we still zero data and ordering data before modifying the
metadata.

This change is required for iomap infrastructure conversion because the
iomap buffered I/O path does not use the same journal infrastructure for
partial block zeroing. The lock ordering of folio lock and starting
transactions is "folio lock -> transaction start", which is opposite of
the current path. Therefore, zeroing partial blocks cannot be performed
under the active handle.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-9-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:52 -04:00
Zhang Yi
ad1876bc4c ext4: pass allocate range as loff_t to ext4_alloc_file_blocks()
Change ext4_alloc_file_blocks() to accept offset and len in byte
granularity instead of block granularity. This allows callers to pass
byte offsets and lengths directly, and this prepares for moving the
ext4_zero_partial_blocks() call from the while(len) loop for unaligned
append writes, where it only needs to be invoked once before doing block
allocation.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-8-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:52 -04:00
Zhang Yi
d3609a71b7 ext4: remove handle parameters from zero partial block functions
Only journal data mode requires an active journal handle when zeroing
partial blocks. Stop passing handle_t *handle to
ext4_zero_partial_blocks() and related functions, and make
ext4_block_journalled_zero_range() start a handle independently.

This change has no practical impact now because all callers invoke these
functions within the context of an active handle. It prepares for moving
ext4_block_zero_eof() out of an active handle in the next patch, which
is a prerequisite for converting block zero range operations to iomap
infrastructure.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-7-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:52 -04:00
Zhang Yi
69e2d5c1f5 ext4: move ordered data handling out of ext4_block_do_zero_range()
Remove the handle parameter from ext4_block_do_zero_range() and move the
ordered data handling to ext4_block_zero_eof().

This is necessary for truncate up and append writes across a range
extending beyond EOF. The ordered data must be committed before updating
i_disksize to prevent exposing stale on-disk data from concurrent
post-EOF mmap writes during previous folio writeback or in case of
system crash during append writes.

This is unnecessary for partial block hole punching because the entire
punch operation does not provide atomicity guarantees and can already
expose intermediate results in case of crash.

Hole punching can only ever expose data that was there before the punch
but missed zeroing during append / truncate could expose data that was
not visible in the file before the operation.

Since ordered data handling is no longer performed inside
ext4_zero_partial_blocks(), ext4_punch_hole() no longer needs to attach
jinode.

This is prepared for the conversion to the iomap infrastructure, which
does not use ordered data mode while zeroing post-EOF partial blocks.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-6-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:51 -04:00
Zhang Yi
ad11526d15 ext4: rename ext4_block_zero_page_range() to ext4_block_zero_range()
Rename ext4_block_zero_page_range() to ext4_block_zero_range() since the
"page" naming is no longer appropriate for current context. Also change
its signature to take an inode pointer instead of an address_space. This
aligns with the caller ext4_block_zero_eof() and
ext4_zero_partial_blocks().

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-5-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:51 -04:00
Zhang Yi
3b312a6f51 ext4: factor out journalled block zeroing range
Refactor __ext4_block_zero_page_range() by separating the block zeroing
operations for ordered data mode and journal data mode into two distinct
functions:

  - ext4_block_do_zero_range(): handles non-journal data mode with
    ordered data support
  - ext4_block_journalled_zero_range(): handles journal data mode

Also extract a common helper, ext4_load_tail_bh(), to handle buffer head
and folio retrieval, along with the associated error handling. This
prepares for converting the partial block zero range to the iomap
infrastructure.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-4-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:51 -04:00
Zhang Yi
bd099a0565 ext4: rename and extend ext4_block_truncate_page()
Rename ext4_block_truncate_page() to ext4_block_zero_eof() and extend
its signature to accept an explicit 'end' offset instead of calculating
the block boundary. This helper function now can replace all cases
requiring zeroing of the partial EOF block, including the append
buffered write paths in ext4_*_write_end().

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-3-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:51 -04:00
Zhang Yi
5447c8b9de ext4: add did_zero output parameter to ext4_block_zero_page_range()
Add a bool *did_zero output parameter to ext4_block_zero_page_range()
and __ext4_block_zero_page_range(). The parameter reports whether a
partial block was zeroed out, which is needed for the upcoming iomap
buffered I/O conversion.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260327102939.1095257-2-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:57:51 -04:00
David Laight
6ea3b34d86 ext4: fix diagnostic printf formats
The formats for non-terminated names should be "%.*s" not "%*.s".
The kernel currently treats "%*.s" as equivalent to "%*s" whereas
userspace requires it be equivalent to "%*.0s".
Neither is correct here.

Signed-off-by: David Laight <david.laight.linux@gmail.com>
Link: https://patch.msgid.link/20260326201804.3881-1-david.laight.linux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:54:33 -04:00
NeilBrown
52b4fea162 ext4: move dcache manipulation out of __ext4_link()
__ext4_link() has two callers.

- ext4_link() calls it during normal handling of the link() system
  call or similar
- ext4_fc_replay_link_internal() calls it when replaying the journal
  at mount time.

The former needs changes to dcache - instantiating the dentry to the
inode on success.  The latter doesn't need or want any dcache
manipulation.

So move the manipulation out of __ext4_link() and do it in ext4_link()
only.

This requires:
 - passing the qname from the dentry explicitly to __ext4_link.
   The parent dir is already passed.  The dentry is still passed
   in the ext4_link() case purely for use by ext4_fc_track_link().
 - passing the inode separately to ext4_fc_track_link() as the
   dentry will not be instantiated yet.
 - using __ext4_add_entry() in ext4_link, which doesn't need a dentry.
 - moving ihold(), d_instantiate(), drop_nlink() and iput() calls out
   of __ext4_link() into ext4_link().

Note that ext4_inc_count() and drop_nlink() remain in __ext4_link()
as both callers need them and they are not related to the dentry.

This substantially simplifies ext4_fc_replay_link_internal(), and
removes a use of d_alloc() which, it is planned, will be removed.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/20260320000838.3797494-4-neilb@ownmail.net
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:51:34 -04:00
NeilBrown
0f5f14f334 ext4: add ext4_fc_eligible()
Testing EXT4_MF_FC_INELIGIBLE is almost always combined with testing
ext4_fc_disabled().  The code can be simplified by combining these two
in a new ext4_fc_eligible().

In ext4_fc_track_inode() this moves the ext4_fc_disabled() test after
ext4_fc_mark_ineligible(), but as that is a non-op when
ext4_fc_disabled() is true, this is no no consequence.

Note that it is important to still call ext4_fc_mark_ineligible() in
ext4_fc_track_inode() even when ext4_fc_eligible() would return true.
ext4_fc_mark_ineligible() does not ONLY set the "INELIGIBLE" flag but
also updates ->s_fc_ineligible_tid to make sure that the flag remains
set until all ineligible transactions have been committed.

Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/20260320000838.3797494-3-neilb@ownmail.net
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:51:34 -04:00
NeilBrown
2879374604 ext4: split __ext4_add_entry() out of ext4_add_entry()
__ext4_add_entry() is not given a dentry - just inodes and name.
This will help the next patch which simplifies __ex4_link().

Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/20260320000838.3797494-2-neilb@ownmail.net
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:51:34 -04:00
Philipp Hahn
1d749e1102 ext4: prefer IS_ERR_OR_NULL over manual NULL check
Prefer using IS_ERR_OR_NULL() over using IS_ERR() and a manual NULL
check.

Change generated with coccinelle.

To: "Theodore Ts'o" <tytso@mit.edu>
To: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: linux-ext4@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Philipp Hahn <phahn-oss@avm.de>
Link: https://patch.msgid.link/20260310-b4-is_err_or_null-v1-4-bd63b656022d@avm.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-04-09 21:27:24 -04:00
Jakub Kicinski
581d28606c net: remove the netif_get_rx_queue_lease_locked() helpers
The netif_get_rx_queue_lease_locked() API hides the locking
and the descend onto the leased queue. Making the code
harder to follow (at least to me). Remove the API and open
code the descend a bit. Most of the code now looks like:

 if (!leased)
     return __helper(x);

 hw_rxq = ..
 netdev_lock(hw_rxq->dev);
 ret = __helper(x);
 netdev_unlock(hw_rxq->dev);

 return ret;

Of course if we have more code paths that need the wrapping
we may need to revisit. For now, IMHO, having to know what
netif_get_rx_queue_lease_locked() does is not worth the 20LoC
it saves.

Link: https://patch.msgid.link/20260408151251.72bd2482@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:26:28 -07:00
Jakub Kicinski
1508922588 Merge branch 'netkit-support-for-io_uring-zero-copy-and-af_xdp'
Daniel Borkmann says:

====================
netkit: Support for io_uring zero-copy and AF_XDP

Containers use virtual netdevs to route traffic from a physical netdev
in the host namespace. They do not have access to the physical netdev
in the host and thus can't use memory providers or AF_XDP that require
reconfiguring/restarting queues in the physical netdev.

This patchset adds the concept of queue leasing to virtual netdevs that
allow containers to use memory providers and AF_XDP at native speed.
Leased queues are bound to a real queue in a physical netdev and act
as a proxy.

Memory providers and AF_XDP operations take an ifindex and queue id,
so containers would pass in an ifindex for a virtual netdev and a queue
id of a leased queue, which then gets proxied to the underlying real
queue.

We have implemented support for this concept in netkit and tested the
latter against Nvidia ConnectX-6 (mlx5) as well as Broadcom BCM957504
(bnxt_en) 100G NICs. For more details see the individual patches.
====================

Link: https://patch.msgid.link/20260402231031.447597-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:24:35 -07:00
David Wei
65d657d806 selftests/net: Add queue leasing tests with netkit
Add extensive selftests for netkit queue leasing, using io_uring zero
copy test binary inside of a netns with netkit. This checks that memory
providers can be bound against virtual queues in a netkit within a
netns that are leasing from a physical netdev in the default netns.
Also add various test cases around corner cases for the queue creation
itself as well as queue info dumping and teardown in case of netkit in
device pair and single mode.

Signed-off-by: David Wei <dw@davidwei.uk>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/20260402231031.447597-15-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:47 -07:00
Daniel Borkmann
a14fd64748 netkit: Add xsk support for af_xdp applications
Enable support for AF_XDP applications to operate on a netkit device.
The goal is that AF_XDP applications can natively consume AF_XDP
from network namespaces. The use-case from Cilium side is to support
Kubernetes KubeVirt VMs through QEMU's AF_XDP backend. KubeVirt is a
virtual machine management add-on for Kubernetes which aims to provide
a common ground for virtualization. KubeVirt spawns the VMs inside
Kubernetes Pods which reside in their own network namespace just like
regular Pods.

Raw QEMU AF_XDP backend example with eth0 being a physical device with
16 queues where netkit is bound to the last queue (for multi-queue RSS
context can be used if supported by the driver):

  # ethtool -X eth0 start 0 equal 15
  # ethtool -X eth0 start 15 equal 1 context new
  # ethtool --config-ntuple eth0 flow-type ether \
            src 00:00:00:00:00:00 \
            src-mask ff:ff:ff:ff:ff:ff \
            dst $mac dst-mask 00:00:00:00:00:00 \
            proto 0 proto-mask 0xffff action 15
  [ ... setup BPF/XDP prog on eth0 to steer into shared xsk map ... ]
  # ip netns add foo
  # ip link add numrxqueues 2 nk type netkit single
  # ynl --family netdev --output-json --do queue-create \
        --json "{"ifindex": $(ifindex nk), "type": "rx", \
                 "lease": { "ifindex": $(ifindex eth0), \
                            "queue": { "type": "rx", "id": 15 } } }"
  {'id': 1}
  # ip link set nk netns foo
  # ip netns exec foo ip link set lo up
  # ip netns exec foo ip link set nk up
  # ip netns exec foo qemu-system-x86_64 \
          -kernel $kernel \
          -drive file=${image_name},index=0,media=disk,format=raw \
          -append "root=/dev/sda rw console=ttyS0" \
          -cpu host \
          -m $memory \
          -enable-kvm \
          -device virtio-net-pci,netdev=net0,mac=$mac \
          -netdev af-xdp,ifname=nk,id=net0,mode=native,queues=1,start-queue=1,inhibit=on,map-path=$dir/xsks_map \
          -nographic

We have tested the above against a dual-port Nvidia ConnectX-6 (mlx5)
100G NIC with successful network connectivity out of QEMU. An earlier
iteration of this work was presented at LSF/MM/BPF [0] and more
recently at LPC [1].

For getting to a first starting point to connect all things with
KubeVirt, bind mounting the xsk map from Cilium into the VM launcher
Pod which acts as a regular Kubernetes Pod while not perfect, is not
a big problem given its out of reach from the application sitting
inside the VM (and some of the control plane aspects are baked in
the launcher Pod already), so the isolation barrier is still the VM.
Eventually the goal is to have a XDP/XSK redirect extension where
there is no need to have the xsk map, and the BPF program can just
derive the target xsk through the queue where traffic was received
on.

The exposure through netkit is because Cilium should not act as a
proxy handing out xsk sockets. Existing applications expect a netdev
from kernel side and should not need to rewrite just to implement
against a CNI's protocol. Also, all the memory should not be accounted
against Cilium but rather the application Pod itself which is consuming
AF_XDP. Further, on up/downgrades we expect the data plane to being
completely decoupled from the control plane; if Cilium would own the
sockets that would be disruptive. Another use-case which opens up and
is regularly asked from users would be to have DPDK applications on
top of AF_XDP in regular Kubernetes Pods.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://bpfconf.ebpf.io/bpfconf2025/bpfconf2025_material/lsfmmbpf_2025_netkit_borkmann.pdf [0]
Link: https://lpc.events/event/19/contributions/2275/ [1]
Link: https://patch.msgid.link/20260402231031.447597-14-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:47 -07:00
Daniel Borkmann
2544447057 netkit: Add netkit notifier to check for unregistering devices
Add a netdevice notifier in netkit to watch for NETDEV_UNREGISTER events.
If the target device is indeed NETREG_UNREGISTERING and previously leased
a queue to a netkit device, then collect the related netkit devices and
batch-unregister_netdevice_many() them.

If this were not done, then the netkit device would hold a reference on
the physical device preventing it from going away. However, in case of
both io_uring zero-copy as well as AF_XDP this situation is handled
gracefully and the allocated resources are torn down.

In the case where mentioned infra is used through netkit, the applications
have a reference on netkit, and netkit in turn holds a reference on the
physical device. In order to have netkit release the reference on the
physical device, we need such watcher to then unregister the netkit ones.

This is generally quite similar to the dependency handling in case of
tunnels (e.g. vxlan bound to a underlying netdev) where the tunnel device
gets removed along with the physical device.

  # ip a
  [...]
  4: enp10s0f0np0: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default qlen 1000
      link/ether e8:eb:d3:a3:43:f6 brd ff:ff:ff:ff:ff:ff
      inet 10.0.0.2/24 scope global enp10s0f0np0
         valid_lft forever preferred_lft forever
  [...]
  8: nk@NONE: <BROADCAST,MULTICAST,NOARP> mtu 1500 qdisc noop state DOWN group default qlen 1000
      link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff
  [...]

  # rmmod mlx5_ib
  # rmmod mlx5_core
  [...]
  [  309.261822] mlx5_core 0000:0a:00.0 mlx5_0: Port: 1 Link DOWN
  [  344.235236] mlx5_core 0000:0a:00.1: E-Switch: Unload vfs: mode(LEGACY), nvfs(0), necvfs(0), active vports(0)
  [  344.246948] mlx5_core 0000:0a:00.1: E-Switch: Disable: mode(LEGACY), nvfs(0), necvfs(0), active vports(0)
  [  344.463754] mlx5_core 0000:0a:00.1: E-Switch: Disable: mode(LEGACY), nvfs(0), necvfs(0), active vports(0)
  [  344.770155] mlx5_core 0000:0a:00.1: E-Switch: cleanup
  [...]

  # ip a
  [...]
  [ both enp10s0f0np0 and nk gone ]
  [...]

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-13-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:47 -07:00
David Wei
b789acc069 netkit: Implement rtnl_link_ops->alloc and ndo_queue_create
Implement rtnl_link_ops->alloc that allows the number of rx queues to be
set when netkit is created. By default, netkit has only a single rxq (and
single txq). The number of queues is deliberately not allowed to be changed
via ethtool -L and is fixed for the lifetime of a netkit instance.

For netkit device creation, numrxqueues with larger than one rxq can be
specified. These rxqs are leasable to real rxqs in physical netdevs:

  ip link add type netkit peer numrxqueues 64      # for device pair
  ip link add numrxqueues 64 type netkit single    # for single device

The limit of numrxqueues for netkit is currently set to 1024, which allows
leasing multiple real rxqs from physical netdevs.

The implementation of ndo_queue_create() adds a new rxq during the queue
lease operation. We allow to create queues either in single device mode
or for the case of dual device mode for the netkit peer device which gets
placed into the target network namespace. For dual device mode the lease
against the primary device does not make sense for the targeted use cases,
and therefore gets rejected.

We also need to add a lockdep class for netkit, such that lockdep does
not trip over us, similarly done as in commit 0bef512012 ("net: add
netdev_lockdep_set_classes() to virtual drivers").

This is also the last missing bit to netkit for supporting io_uring with
zero-copy mode [0]. Up until this point it was not possible to consume the
latter out of containers or Kubernetes Pods where applications are in their
own network namespace.

io_uring example with eth0 being a physical device with 16 queues where
netkit is bound to the last queue, iou-zcrx.c is binary from selftests;
ethtool configuration (tcp-data-split, hds_thresh, RSS, flow steering)
is done on the physical device by the control plane; here, flow steering
to that queue is based on the service VIP:port of the server utilizing
io_uring:

  # ethtool -X eth0 start 0 equal 15
  # ethtool -X eth0 start 15 equal 1 context new
  # ethtool --config-ntuple eth0 flow-type tcp4 dst-ip 1.2.3.4 dst-port 5000 action 15
  # ip netns add foo
  # ip link add type netkit peer numrxqueues 2
  # ynl --family netdev --output-json --do queue-create \
        --json "{"ifindex": $(ifindex nk0), "type": "rx", \
                 "lease": { "ifindex": $(ifindex eth0), \
                            "queue": { "type": "rx", "id": 15 } } }"
  {'id': 1}
  # ip link set nk0 netns foo
  # ip link set nk1 up
  # ip netns exec foo ip link set lo up
  # ip netns exec foo ip link set nk0 up
  # ip netns exec foo ip addr add 1.2.3.4/32 dev nk0
  [ ... setup routing etc to get external traffic into the netns ... ]
  # ip netns exec foo ./iou-zcrx -s -p 5000 -i nk0 -q 1

Remote io_uring client:

  # ./iou-zcrx -c -h 1.2.3.4 -p 5000 -l 12840 -z 65536

We have tested the above against a Broadcom BCM957504 (bnxt_en) 100G NIC,
supporting TCP header/data split.

Similarly, this also works for devmem which we tested using ncdevmem:

  # ip netns exec foo ./ncdevmem -s 1.2.3.4 -l -p 5000 -f nk0 -t 1 -q 1

And on the remote client:

  # ./ncdevmem -s 1.2.3.4 -p 5000 -f eth0

For Cilium, the plan is to open up support for the various memory providers
for regular Kubernetes Pods when Cilium is configured with netkit datapath
mode.

Signed-off-by: David Wei <dw@davidwei.uk>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://kernel-recipes.org/en/2024/schedule/efficient-zero-copy-networking-using-io_uring [0]
Link: https://patch.msgid.link/20260402231031.447597-12-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:47 -07:00
Daniel Borkmann
4810389605 netkit: Add single device mode for netkit
Add a single device mode for netkit instead of netkit pairs. The primary
target for the paired devices is to connect network namespaces, of course,
and support has been implemented in projects like Cilium [0]. For the rxq
leasing the plan is to support two main scenarios related to single device
mode:

* For the use-case of io_uring zero-copy, the control plane can either
  set up a netkit pair where the peer device can perform rxq leasing which
  is then tied to the lifetime of the peer device, or the control plane
  can use a regular netkit pair to connect the hostns to a Pod/container
  and dynamically add/remove rxq leasing through a single device without
  having to interrupt the device pair. In the case of io_uring, the memory
  pool is used as skb non-linear pages, and thus the skb will go its way
  through the regular stack into netkit. Things like the netkit policy when
  no BPF is attached or skb scrubbing etc apply as-is in case the paired
  devices are used, or if the backend memory is tied to the single device
  and traffic goes through a paired device.

* For the use-case of AF_XDP, the control plane needs to use netkit in the
  single device mode. The single device mode currently enforces only a
  pass policy when no BPF is attached, and does not yet support BPF link
  attachments for AF_XDP. skbs sent to that device get dropped at the
  moment. Given AF_XDP operates at a lower layer of the stack tying this
  to the netkit pair did not make sense. In future, the plan is to allow
  BPF at the XDP layer which can: i) process traffic coming from the AF_XDP
  application (e.g. QEMU with AF_XDP backend) to filter egress traffic or
  to push selected egress traffic up to the single netkit device to the
  local stack (e.g. DHCP requests), and ii) vice-versa skbs sent to the
  single netkit into the AF_XDP application (e.g. DHCP replies). Also,
  the control-plane can dynamically manage rxq leasing for the single
  netkit device without having to interrupt (e.g. down/up cycle) the main
  netkit pair for the Pod which has traffic going in and out.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Jordan Rife <jordan@jrife.io>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://docs.cilium.io/en/stable/operations/performance/tuning/#netkit-device-mode [0]
Link: https://patch.msgid.link/20260402231031.447597-11-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:47 -07:00
Daniel Borkmann
910f636db9 xsk: Proxy pool management for leased queues
Similarly to the netif_mp_{open,close}_rxq handling for leased queues, proxy
the xsk_{reg,clear}_pool_at_qid via netif_get_rx_queue_lease_locked such
that in case a virtual netdev picked a leased rxq, the request gets through
to the real rxq in the physical netdev. The proxying is only relevant for
queue_id < dev->real_num_rx_queues since right now it's only supported for
rxqs.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-10-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:47 -07:00
Daniel Borkmann
9368397fb9 xsk: Extend xsk_rcv_check validation
xsk_rcv_check tests for inbound packets to see whether they match
the bound AF_XDP socket. Refactor the test into a small helper
xsk_dev_queue_valid and move the validation against xs->dev and
xs->queue_id there.

The fast-path case stays in place and allows for quick return in
xsk_dev_queue_valid. If it fails, the validation is extended to
check whether the AF_XDP socket is bound against a leased queue,
and if so, the test is redone.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-9-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:46 -07:00
David Wei
222b5566a0 net: Proxy netdev_queue_get_dma_dev for leased queues
Extend netdev_queue_get_dma_dev to return the physical device of the
real rxq for DMA in case the queue was leased. This allows memory
providers like io_uring zero-copy or devmem to bind to the physically
leased rxq via virtual devices such as netkit.

Signed-off-by: David Wei <dw@davidwei.uk>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-8-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:46 -07:00
David Wei
5602ad61eb net: Proxy netif_mp_{open,close}_rxq for leased queues
When a process in a container wants to setup a memory provider, it will
use the virtual netdev and a leased rxq, and call netif_mp_{open,close}_rxq
to try and restart the queue. At this point, proxy the queue restart on
the real rxq in the physical netdev.

For memory providers (io_uring zero-copy rx and devmem), it causes the
real rxq in the physical netdev to be filled from a memory provider that
has DMA mapped memory from a process within a container.

Signed-off-by: David Wei <dw@davidwei.uk>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-7-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:46 -07:00
Daniel Borkmann
1e91c98bc9 net: Slightly simplify net_mp_{open,close}_rxq
net_mp_open_rxq is currently not used in the tree as all callers are
using __net_mp_open_rxq directly, and net_mp_close_rxq is only used
once while all other locations use __net_mp_close_rxq.

Consolidate into a single API, netif_mp_{open,close}_rxq, using the
netif_ prefix to indicate that the caller is responsible for locking.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-6-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:46 -07:00
Daniel Borkmann
22fdf28f7c net, ethtool: Disallow leased real rxqs to be resized
Similar to AF_XDP, do not allow queues in a physical netdev to be resized
by ethtool -L when they are leased. Cover channel resize paths (both
netlink and ioctl) to reject resizing when the queues would be affected.

Given we need to have different checks for RX vs TX, detangle the code into
a two-loop version rather than the range of new_combined + min(new_rx, new_tx)
to old_combined + max(old_rx, old_tx).

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-5-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:46 -07:00
Daniel Borkmann
21d58b35e5 net: Add lease info to queue-get response
Populate nested lease info to the queue-get response that returns the
ifindex, queue id with type and optionally netns id if the device
resides in a different netns.

Example with ynl client when using AF_XDP via queue leasing:

  # ip a
  [...]
  4: enp10s0f0np0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 xdp/id:24 qdisc mq state UP group default qlen 1000
    link/ether e8:eb:d3:a3:43:f6 brd ff:ff:ff:ff:ff:ff
    inet 10.0.0.2/24 scope global enp10s0f0np0
       valid_lft forever preferred_lft forever
    inet6 fe80::eaeb:d3ff:fea3:43f6/64 scope link proto kernel_ll
       valid_lft forever preferred_lft forever
  [...]

  # ethtool -i enp10s0f0np0
  driver: mlx5_core
  [...]

  # ynl --family netdev --output-json --do queue-get \
        --json '{"ifindex": 4, "id": 15, "type": "rx"}'
  {'id': 15,
   'ifindex': 4,
   'lease': {'ifindex': 8, 'netns-id': 0, 'queue': {'id': 1, 'type': 'rx'}},
   'napi-id': 8227,
   'type': 'rx',
   'xsk': {}}

  # ip netns list
  foo (id: 0)

  # ip netns exec foo ip a
  [...]
  8: nk@NONE: <BROADCAST,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
      link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff
      inet6 fe80::200:ff:fe00:0/64 scope link proto kernel_ll
         valid_lft forever preferred_lft forever
  [...]

  # ip netns exec foo ethtool -i nk
  driver: netkit
  [...]

  # ip netns exec foo ls /sys/class/net/nk/queues/
  rx-0  rx-1  tx-0

  # ip netns exec foo ynl --family netdev --output-json --do queue-get \
        --json '{"ifindex": 8, "id": 1, "type": "rx"}'
  {"id": 1, "type": "rx", "ifindex": 8, "xsk": {}}

Note that the caller of netdev_nl_queue_fill_one() holds the netdevice
lock. For the queue-get we do not lock both devices. When queues get
{un,}leased, both devices are locked, thus if __netif_get_rx_queue_lease()
returns a lease pointer, it points to a valid device. The netns-id is
fetched via peernet2id_alloc() similarly as done in OVS.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-4-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:46 -07:00
Daniel Borkmann
d04686d9bc net: Implement netdev_nl_queue_create_doit
Implement netdev_nl_queue_create_doit which creates a new rx queue in a
virtual netdev and then leases it to a rx queue in a physical netdev.

Example with ynl client:

  # ynl --family netdev --output-json --do queue-create \
        --json '{"ifindex": 8, "type": "rx", "lease": {"ifindex": 4, "queue": {"type": "rx", "id": 15}}}'
  {'id': 1}

Note that the netdevice locking order is always from the virtual to
the physical device.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-3-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-09 18:21:45 -07:00