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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: Clear (ClamAV 1.4.3/27984/Mon Apr 27 08:24:37 2026) On 4/27/26 8:01 AM, Ido Schimmel wrote: > On Sun, Apr 26, 2026 at 05:47:38PM +0200, Justin Iurman wrote: >> Ido, Daniel, >> >> As I said, my vote would definitely go to the solution without a sysctl for >> the very reason Ido mentioned. Note that an upper bound of 32 is kind of >> unrealistic, although super (SUPER!) safe. Sending more than 8 Extension >> Headers (assuming a different type for each) is not standard behavior and >> would make you non-RFC-compliant anyway. But I'm happy with 32, as long as >> we don't define a sysctl for that. > > OK, so given that: > > 1. 32 is super safe and solves the issue. > > 2. We will likely have to maintain a sysctl forever. > > 3. A sysctl has the potential to be incompatible with the upcoming > "enforce_ext_hdr_order" sysctl. > > I believe we can just go with the simplest solution of hard coding 32 as > a limit and drop the sysctl. Although to be honest, I like it slightly better if we could actually constrain it to just 8 by default rather than 32 given 32 is just an arbitrary 'large enough' pick vs 8 something sensible derived from the RFC and the sysctl knob is not out of place. Eric, what's your pref? Thanks, Daniel