From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [REGRESSION][PATCH V4 2/3] bpf jit: Let the x86 jit handle negative offsets Date: Fri, 30 Mar 2012 20:58:00 +0200 Message-ID: <1333133880.2325.2430.camel@edumazet-glaptop> References: <4F75CA89.4010709@googlemail.com> <4F75D015.30609@googlemail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "David S. Miller" To: kaffeemonster@googlemail.com Return-path: In-Reply-To: <4F75D015.30609@googlemail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, 2012-03-30 at 17:24 +0200, Jan Seiffert wrote: > Now the helper function from filter.c for negative offsets is exported, > it can be used it in the jit to handle negative offsets. > > First modify the asm load helper functions to handle: > - know positive offsets > - know negative offsets > - any offset > > then the compiler can be modified to explicitly use these helper > when appropriate. > > This fixes the case of a negative X register and allows to lift > the restriction that bpf programs with negative offsets can't > be jited. > > Signed-of-by: Jan Seiffert Nice work Jan, thanks a lot. Signed-off-by: Eric Dumazet