kernel/linux.git/net/ethtool/rss.c, branch v6.12.93

ethtool: rss: fix hkey leak when indir_size is 0

2026-06-09T10:25:40+00:00

[ Upstream commit 78ccf1a70c6378e1f5073a8c2209b5129067b925 ] rss_get_data_alloc() allocates a single buffer that backs both the indirection table and the hash key, but only assigned data->indir_table when indir_size was nonzero. The expectation was that no driver implements RSS without supporting indirection table but apparently enic does just that (it's the only such in-tree driver). enic has get_rxfh_key_size but no get_rxfh_indir_size. data->indir_table stays as NULL, hkey gets set but rss_get_data_free() kfree(data->indir_table) is a nop and the allocation leaks. Always store the allocation base in data->indir_table so the free path is unambiguous. No caller treats indir_table as a sentinel; everything keys off indir_size. Fixes: 7112a04664bf ("ethtool: add netlink based get rss support") Link: https://patch.msgid.link/20260522230647.1705600-6-kuba@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ethtool: rss: fix hiding unsupported fields in dumps

2025-02-17T09:05:00+00:00

[ Upstream commit 244f8aa46fa9e2f4ea5fe0e04988b395d5e30fc7 ] Commit ec6e57beaf8b ("ethtool: rss: don't report key if device doesn't support it") intended to stop reporting key fields for additional rss contexts if device has a global hashing key. Later we added dump support and the filtering wasn't properly added there. So we end up reporting the key fields in dumps but not in dos: # ./pyynl/cli.py --spec netlink/specs/ethtool.yaml --do rss-get \ --json '{"header": {"dev-index":2}, "context": 1 }' { "header": { ... }, "context": 1, "indir": [0, 1, 2, 3, ...]] } # ./pyynl/cli.py --spec netlink/specs/ethtool.yaml --dump rss-get [ ... snip context 0 ... { "header": { ... }, "context": 1, "indir": [0, 1, 2, 3, ...], -> "input_xfrm": 255, -> "hfunc": 1, -> "hkey": "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" } ] Hide these fields correctly. The drivers/net/hw/rss_ctx.py selftest catches this when run on a device with single key, already: # Check| At /root/./ksft-net-drv/drivers/net/hw/rss_ctx.py, line 381, in test_rss_context_dump: # Check| ksft_ne(set(data.get('hkey', [1])), {0}, "key is all zero") # Check failed {0} == {0} key is all zero not ok 8 rss_ctx.test_rss_context_dump Fixes: f6122900f4e2 ("ethtool: rss: support dumping RSS contexts") Reviewed-by: Gal Pressman Reviewed-by: Joe Damato Link: https://patch.msgid.link/20250201013040.725123-2-kuba@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ethtool: rss: support skipping contexts during dump

2024-08-12T13:16:24+00:00

Applications may want to deal with dynamic RSS contexts only. So dumping context 0 will be counter-productive for them. Support starting the dump from a given context ID. Alternative would be to implement a dump flag to skip just context 0, not sure which is better... Reviewed-by: Edward Cree Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

ethtool: rss: support dumping RSS contexts

2024-08-12T13:16:24+00:00

Now that we track RSS contexts in the core we can easily dump them. This is a major introspection improvement, as previously the only way to find all contexts would be to try all ids (of which there may be 2^32 - 1). Don't use the XArray iterators (like xa_for_each_start()) as they do not move the index past the end of the array once done, which caused multiple bugs in Netlink dumps in the past. Reviewed-by: Edward Cree Reviewed-by: Joe Damato Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

ethtool: rss: report info about additional contexts from XArray

2024-08-12T13:16:24+00:00

IOCTL already uses the XArray when reporting info about additional contexts. Do the same thing in netlink code. Reviewed-by: Edward Cree Reviewed-by: Joe Damato Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

ethtool: rss: move the device op invocation out of rss_prepare_data()

2024-08-12T13:16:24+00:00

Factor calling device ops out of rss_prepare_data(). Next patch will add alternative path using xarray. No functional changes. Reviewed-by: Joe Damato Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

ethtool: rss: don't report key if device doesn't support it

2024-08-12T13:16:24+00:00

marvell/otx2 and mvpp2 do not support setting different keys for different RSS contexts. Contexts have separate indirection tables but key is shared with all other contexts. This is likely fine, indirection table is the most important piece. Don't report the key-related parameters from such drivers. This prevents driver-errors, e.g. otx2 always writes the main key, even when user asks to change per-context key. The second reason is that without this change tracking the keys by the core gets complicated. Even if the driver correctly reject setting key with rss_context != 0, change of the main key would have to be reflected in the XArray for all additional contexts. Since the additional contexts don't have their own keys not including the attributes (in Netlink speak) seems intuitive. ethtool CLI seems to deal with it just fine. Having to set the flag in majority of the drivers is a bit tedious but not reporting the key is a safer default. Reviewed-by: Edward Cree Reviewed-by: Joe Damato Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

ethtool: make ethtool_ops::cap_rss_ctx_supported optional

2024-08-12T13:16:24+00:00

cap_rss_ctx_supported was created because the API for creating and configuring additional contexts is mux'ed with the normal RSS API. Presence of ops does not imply driver can actually support rss_context != 0 (in fact drivers mostly ignore that field). cap_rss_ctx_supported lets core check that the driver is context-aware before calling it. Now that we have .create_rxfh_context, there is no such ambiguity. We can depend on presence of the op. Make setting the bit optional. Reviewed-by: Gal Pressman Reviewed-by: Edward Cree Reviewed-by: Joe Damato Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

ethtool: rss: echo the context number back

2024-07-25T23:23:47+00:00

The response to a GET request in Netlink should fully identify the queried object. RSS_GET accepts context id as an input, so it must echo that attribute back to the response. After (assuming context 1 has been created): $ ./cli.py --spec netlink/specs/ethtool.yaml \ --do rss-get \ --json '{"header": {"dev-index": 2}, "context": 1}' {'context': 1, 'header': {'dev-index': 2, 'dev-name': 'eth0'}, [...] Fixes: 7112a04664bf ("ethtool: add netlink based get rss support") Acked-by: Paolo Abeni Reviewed-by: Joe Damato Link: https://patch.msgid.link/20240724234249.2621109-3-kuba@kernel.org Signed-off-by: Jakub Kicinski

net: ethtool: add support for symmetric-xor RSS hash

2023-12-14T06:07:16+00:00

Symmetric RSS hash functions are beneficial in applications that monitor both Tx and Rx packets of the same flow (IDS, software firewalls, ..etc). Getting all traffic of the same flow on the same RX queue results in higher CPU cache efficiency. A NIC that supports "symmetric-xor" can achieve this RSS hash symmetry by XORing the source and destination fields and pass the values to the RSS hash algorithm. The user may request RSS hash symmetry for a specific algorithm, via: # ethtool -X eth0 hfunc symmetric-xor or turn symmetry off (asymmetric) by: # ethtool -X eth0 hfunc The specific fields for each flow type should then be specified as usual via: # ethtool -N|-U eth0 rx-flow-hash s|d|f|n Reviewed-by: Wojciech Drewek Signed-off-by: Ahmed Zaki Link: https://lore.kernel.org/r/20231213003321.605376-4-ahmed.zaki@intel.com Signed-off-by: Jakub Kicinski