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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: None X-Rspamd-Queue-Id: 1870A11D718A5 X-Spamd-Result: default: False [2.39 / 30.00]; SUSPICIOUS_RECIPS(1.50)[]; DATE_IN_PAST(1.00)[128]; MIME_GOOD(-0.10)[text/plain]; BAYES_HAM(-0.01)[44.09%]; MAILCOW_DOMAIN_HEADER_FROM(0.00)[bootlin.com]; URIBL_BLOCKED(0.00)[bootlin.com:mid,localhost:rdns,localhost:helo]; DKIM_SIGNED(0.00)[bootlin.com:s=dkim]; ARC_NA(0.00)[]; BCC(0.00)[]; MIME_TRACE(0.00)[0:+]; FROM_HAS_DN(0.00)[]; FREEMAIL_CC(0.00)[kernel.org,lunn.ch,davemloft.net,google.com,redhat.com,gmail.com,foss.st.com,armlinux.org.uk,oss.qualcomm.com,tipi-net.de,broadcom.com,bootlin.com,vger.kernel.org,lists.infradead.org,st-md-mailman.stormreply.com,dama.to]; TAGGED_RCPT(0.00)[sashiko,netdev]; TO_MATCH_ENVRCPT_SOME(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; RCPT_COUNT_TWELVE(0.00)[21]; NEURAL_HAM(-0.00)[-1.000]; RCVD_COUNT_ZERO(0.00)[0]; MID_RHS_MATCH_FROM(0.00)[]; TO_DN_SOME(0.00)[] Hi Jakub, On 10/7/26 01:33, Jakub Kicinski wrote: > On Tue, 6 Oct 2026 09:59:29 +0200 Maxime Chevallier wrote: >>> [Severity: Medium] >>> rss_get_data_alloc() is shared by RSS_GET, RSS_SET and RSS_CREATE. Does >>> this drop flow-hash reporting for devices that have ->get_rxfh but report >>> 0/0 sizes? >> >> Yes it does, that's the intended behaviour here. RSS bits are all optional, >> but does it make sense to report hashing params when the indirection table >> is size 0 and key len is 0 ? > > Not sure if there's an implementation in the tree but > it's possible to implement poor man's RSS on strict > power-of-2 queue set with some hashing built into the > Rx engine, without a key. We'd still want to control > which fields are hashed in this case. > > In the Netlink API we combine the two so we'd break this? Hmm I wasn't aware of that :( I guess the safe choice is to check on -EOPNOTSUPP for .get_rxfh() + 0-len indir table / 0-size key and skip the device during the dump instead of returning early ? Maxime