From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net 2/2] s390/bpf: fix bpf frame pointer setup Date: Wed, 03 Jun 2015 19:32:17 -0700 (PDT) Message-ID: <20150603.193217.279547964953271748.davem@davemloft.net> References: <1433224115-28411-1-git-send-email-ast@plumgrid.com> <1433224115-28411-2-git-send-email-ast@plumgrid.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: holzheu@linux.vnet.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, daniel@iogearbox.net, netdev@vger.kernel.org To: ast@plumgrid.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:43353 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751809AbbFDCcS (ORCPT ); Wed, 3 Jun 2015 22:32:18 -0400 In-Reply-To: <1433224115-28411-2-git-send-email-ast@plumgrid.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Alexei Starovoitov Date: Mon, 1 Jun 2015 22:48:35 -0700 > From: Michael Holzheu > > Currently the bpf frame pointer is set to the old r15. This is > wrong because of packed stack. Fix this and adjust the frame pointer > to respect packed stack. This now generates a prolog like the following: > > 3ff8001c3fa: eb67f0480024 stmg %r6,%r7,72(%r15) > 3ff8001c400: ebcff0780024 stmg %r12,%r15,120(%r15) > 3ff8001c406: b904001f lgr %r1,%r15 <- load backchain > 3ff8001c40a: 41d0f048 la %r13,72(%r15) <- load adjusted bfp > 3ff8001c40e: a7fbfd98 aghi %r15,-616 > 3ff8001c412: e310f0980024 stg %r1,152(%r15) <- save backchain > > Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend") > Signed-off-by: Michael Holzheu > Acked-by: Heiko Carstens > Signed-off-by: Alexei Starovoitov Applied.