Hi Roman, On Wed, Feb 21, 2018 at 09:38:52AM +0100, Roman Kapl wrote: > On 02/21/2018 08:45 AM, Phil Sutter wrote: > > On Mon, Feb 19, 2018 at 09:32:51PM +0100, Roman Kapl wrote: > >> So far, if the filter was too large to fit in the allocated skb, the > >> kernel did not return any error and stopped dumping. Modify the dumper > >> so that it returns -EMSGSIZE when a filter fails to dump and it is the > >> first filter in the skb. If we are not first, we will get a next chance > >> with more room. > >> > >> I understand this is pretty near to being an API change, but the > >> original design (silent truncation) can be considered a bug. > >> > >> Note: The error case can happen pretty easily if you create a filter > >> with 32 actions and have 4kb pages. Also recent versions of iproute try > >> to be clever with their buffer allocation size, which in turn leads to > > I'm curious, what does it lead to? :) > > > > Thanks, Phil > > tc will dump all filters up to the big one, then it will stop silently. > So it will seem as if you have less filters. > > The new behavior is the same, but tc will at leas print the EMSGSIZE > error. It does not handle it in any other way.
I got that, yes. Though your commit message stops mid-sentence and I wondered what the dynamic buffer allocation "in turn leads to". Thanks, Phil
