linux/tools/net/ynl/pyynl, branch master

tools/ynl: Make YnlFamily closeable as a context manager

2026-04-14T15:17:01Z

YnlFamily opens an AF_NETLINK socket in __init__ but has no way to release it other than leaving it to the GC. YnlFamily holds a self reference cycle through SpecFamily's self.family = self in its super().__init__() call, so refcount GC cannot reclaim it and the socket stays open until the cyclic GC runs. If a test creates a guest netns, instantiates a YnlFamily inside it via NetNSEnter(), performs some test case work via Ynl, and then deletes the netns, then the 'ip netns del' only drops the mount binding and cleanup_net in the kernel never runs, so any subsequent test case assertions that objects got cleaned up would fail given this only gets triggered later via cyclic GC run. Add an explicit close() that closes the netlink socket and wire up the __enter__/__exit__ so callers can scope the instance deterministically via 'with YnlFamily(...) as ynl: ...'. Signed-off-by: Daniel Borkmann Reviewed-by: Nikolay Aleksandrov Link: https://patch.msgid.link/20260413220809.604592-2-daniel@iogearbox.net Signed-off-by: Jakub Kicinski

tools: ynl: move ethtool.py to selftest

2026-04-12T18:23:49Z

We have converted all the samples to selftests. This script is the last piece of random "PoC" code we still have lying around. Let's move it to tests. Signed-off-by: Hangbin Liu Link: https://patch.msgid.link/20260408-b4-ynl_ethtool-v2-1-7623a5e8f70b@gmail.com Signed-off-by: Jakub Kicinski

tools: ynl: rework policy access to support recursion

2026-03-18T23:41:42Z

Donald points out that the current naive implementation using dicts breaks if policy is recursive (child nest uses policy idx already used by its parent). Lean more into the NlPolicy class. This lets us "render" the policy on demand, when user accesses it. If someone wants to do an infinite walk that's on them :) Show policy info as attributes of the class and use dict format to descend into sub-policies for extra neatness. Reviewed-by: Donald Hunter Link: https://patch.msgid.link/20260313232047.2068518-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

tools: ynl: cli: add --policy support

2026-03-11T02:33:00Z

Add --policy flag which can be combined with --do or --dump to query the kernel's netlink policy for an operation instead of executing it. Examples: $ ynl --family netdev --do dev-get --policy {'ifindex': {'max-value': 4294967295, 'min-value': 1, 'type': 'u32'}} $ ynl --family ethtool --do channels-get --policy --output-json {"header": {"type": "nested", "policy": {"dev-index": ...}}} $ ynl --family netdev --dump dev-get --policy {} Link: https://patch.msgid.link/20260310005337.3594225-6-kuba@kernel.org Signed-off-by: Jakub Kicinski

tools: ynl: add Python API for easier access to policies

2026-03-11T02:32:46Z

The format of Netlink policy dump is a bit curious with messages in the same dump carrying both attrs and mapping info. Plus each message carries a single piece of the puzzle the caller must then reassemble. I need to do this reassembly for a test, but I think it's generally useful. So let's add proper support to YnlFamily to return more user-friendly representation. See the various docs in the patch for more details. Link: https://patch.msgid.link/20260310005337.3594225-5-kuba@kernel.org Signed-off-by: Jakub Kicinski

tools: ynl: add short doc to class YnlFamily

2026-03-11T02:30:03Z

The class is quite long. It's getting hard to find the user-facing methods. Add a short doc at the class level explaining the main API. Link: https://patch.msgid.link/20260310005337.3594225-4-kuba@kernel.org Signed-off-by: Jakub Kicinski

tools: ynl: move policy decoding out of NlMsg

2026-03-11T02:30:03Z

We'll soon need to decode policies from dump so move _decode_policy() out of class NlMsg. Link: https://patch.msgid.link/20260310005337.3594225-3-kuba@kernel.org Signed-off-by: Jakub Kicinski

tools: ynl: handle pad type during decode

2026-03-11T02:30:03Z

Apparently Python code only handled the 'pad' type in structs until now. Add it to attr decoding. nlctrl policy dumps need it. Link: https://patch.msgid.link/20260310005337.3594225-2-kuba@kernel.org Signed-off-by: Jakub Kicinski

tools: ynl: cli: order set->list conversion in JSON output

2026-03-11T00:54:02Z

NIPA tries to make sure that HW tests don't modify system state. It dumps some well known configs before and after the test and compares the outputs. Make sure that YNL json output is stable. Converting sets to lists with a naive list(o) results in a random order. Link: https://patch.msgid.link/20260307175916.1652518-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

tools: ynl: cli: make the output compact

2026-02-03T01:06:14Z

Make the default (non-JSON) output more compact. Looking at RSS context dumps is pretty much impossible without this, because default print shows the indirection table with line per entry: 'indir': [0, 1, 2, ... And indirection tables have 100-200 entries each. The compact output is far more readable: 'indir': [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, Reviewed-by: Donald Hunter Link: https://patch.msgid.link/20260131203029.1173492-1-kuba@kernel.org Signed-off-by: Jakub Kicinski