From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751450AbcFVF3h (ORCPT ); Wed, 22 Jun 2016 01:29:37 -0400 Received: from ozlabs.org ([103.22.144.67]:50829 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750957AbcFVF3f (ORCPT ); Wed, 22 Jun 2016 01:29:35 -0400 Message-ID: <1466572831.19785.5.camel@ellerman.id.au> Subject: Re: [PATCH] ppc: Fix BPF JIT for ABIv2 From: Michael Ellerman To: "Naveen N. Rao" , Thadeu Lima de Souza Cascardo Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, Matt Evans , Daniel Borkmann , Alexei Starovoitov , Denis Kirjanov , Paul Mackerras , "David S. Miller" , Ananth N Mavinakayanahalli Date: Wed, 22 Jun 2016 15:20:31 +1000 In-Reply-To: <20160621085807.GE8886@naverao1-tp.localdomain> References: <908d3552b5eb240b28f70aee7c4c86e2b600aa02.1465304785.git.naveen.n.rao@linux.vnet.ibm.com> <3rWKtT2tSrz9t2G@ozlabs.org> <20160617130042.GO3516@indiana.gru.redhat.com> <20160619174914.GC8886@naverao1-tp.localdomain> <20160620185620.GD3516@indiana.gru.redhat.com> <20160621085807.GE8886@naverao1-tp.localdomain> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.16.5-1ubuntu3.1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2016-06-21 at 14:28 +0530, Naveen N. Rao wrote: > On 2016/06/20 03:56PM, Thadeu Lima de Souza Cascardo wrote: > > On Sun, Jun 19, 2016 at 11:19:14PM +0530, Naveen N. Rao wrote: > > > On 2016/06/17 10:00AM, Thadeu Lima de Souza Cascardo wrote: > > > > > > > > Hi, Michael and Naveen. > > > > > > > > I noticed independently that there is a problem with BPF JIT and ABIv2, and > > > > worked out the patch below before I noticed Naveen's patchset and the latest > > > > changes in ppc tree for a better way to check for ABI versions. > > > > > > > > However, since the issue described below affect mainline and stable kernels, > > > > would you consider applying it before merging your two patchsets, so that we can > > > > more easily backport the fix? > > > > > > Hi Cascardo, > > > Given that this has been broken on ABIv2 since forever, I didn't bother > > > fixing it. But, I can see why this would be a good thing to have for > > > -stable and existing distros. However, while your patch below may fix > > > the crash you're seeing on ppc64le, it is not sufficient -- you'll need > > > changes in bpf_jit_asm.S as well. > > > > Hi, Naveen. > > > > Any tips on how to exercise possible issues there? Or what changes you think > > would be sufficient? > > The calling convention is different with ABIv2 and so we'll need changes > in bpf_slow_path_common() and sk_negative_common(). > > However, rather than enabling classic JIT for ppc64le, are we better off > just disabling it? > > --- a/arch/powerpc/Kconfig > +++ b/arch/powerpc/Kconfig > @@ -128,7 +128,7 @@ config PPC > select IRQ_FORCED_THREADING > select HAVE_RCU_TABLE_FREE if SMP > select HAVE_SYSCALL_TRACEPOINTS > - select HAVE_CBPF_JIT > + select HAVE_CBPF_JIT if CPU_BIG_ENDIAN > select HAVE_ARCH_JUMP_LABEL > select ARCH_HAVE_NMI_SAFE_CMPXCHG > select ARCH_HAS_GCOV_PROFILE_ALL > > > Michael, > Let me know your thoughts on whether you intend to take this patch or > Cascardo's patch for -stable before the eBPF patches. I can redo my > patches accordingly. Can one of you send me a proper version of this patch, with change log and sign-off etc. cheers From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Ellerman Subject: Re: [PATCH] ppc: Fix BPF JIT for ABIv2 Date: Wed, 22 Jun 2016 15:20:31 +1000 Message-ID: <1466572831.19785.5.camel@ellerman.id.au> References: <908d3552b5eb240b28f70aee7c4c86e2b600aa02.1465304785.git.naveen.n.rao@linux.vnet.ibm.com> <3rWKtT2tSrz9t2G@ozlabs.org> <20160617130042.GO3516@indiana.gru.redhat.com> <20160619174914.GC8886@naverao1-tp.localdomain> <20160620185620.GD3516@indiana.gru.redhat.com> <20160621085807.GE8886@naverao1-tp.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Cc: Matt Evans , Daniel Borkmann , Alexei Starovoitov , netdev@vger.kernel.org, Denis Kirjanov , linux-kernel@vger.kernel.org, Paul Mackerras , linuxppc-dev@lists.ozlabs.org, "David S. Miller" , Ananth N Mavinakayanahalli To: "Naveen N. Rao" , Thadeu Lima de Souza Cascardo Return-path: In-Reply-To: <20160621085807.GE8886@naverao1-tp.localdomain> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+glppe-linuxppc-embedded-2=m.gmane.org@lists.ozlabs.org Sender: "Linuxppc-dev" List-Id: netdev.vger.kernel.org T24gVHVlLCAyMDE2LTA2LTIxIGF0IDE0OjI4ICswNTMwLCBOYXZlZW4gTi4gUmFvIHdyb3RlOgo+ IE9uIDIwMTYvMDYvMjAgMDM6NTZQTSwgVGhhZGV1IExpbWEgZGUgU291emEgQ2FzY2FyZG8gd3Jv dGU6Cj4gPiBPbiBTdW4sIEp1biAxOSwgMjAxNiBhdCAxMToxOToxNFBNICswNTMwLCBOYXZlZW4g Ti4gUmFvIHdyb3RlOgo+ID4gPiBPbiAyMDE2LzA2LzE3IDEwOjAwQU0sIFRoYWRldSBMaW1hIGRl IFNvdXphIENhc2NhcmRvIHdyb3RlOgo+ID4gPiA+IAo+ID4gPiA+IEhpLCBNaWNoYWVsIGFuZCBO YXZlZW4uCj4gPiA+ID4gCj4gPiA+ID4gSSBub3RpY2VkIGluZGVwZW5kZW50bHkgdGhhdCB0aGVy ZSBpcyBhIHByb2JsZW0gd2l0aCBCUEYgSklUIGFuZCBBQkl2MiwgYW5kCj4gPiA+ID4gd29ya2Vk IG91dCB0aGUgcGF0Y2ggYmVsb3cgYmVmb3JlIEkgbm90aWNlZCBOYXZlZW4ncyBwYXRjaHNldCBh bmQgdGhlIGxhdGVzdAo+ID4gPiA+IGNoYW5nZXMgaW4gcHBjIHRyZWUgZm9yIGEgYmV0dGVyIHdh eSB0byBjaGVjayBmb3IgQUJJIHZlcnNpb25zLgo+ID4gPiA+IAo+ID4gPiA+IEhvd2V2ZXIsIHNp bmNlIHRoZSBpc3N1ZSBkZXNjcmliZWQgYmVsb3cgYWZmZWN0IG1haW5saW5lIGFuZCBzdGFibGUg a2VybmVscywKPiA+ID4gPiB3b3VsZCB5b3UgY29uc2lkZXIgYXBwbHlpbmcgaXQgYmVmb3JlIG1l cmdpbmcgeW91ciB0d28gcGF0Y2hzZXRzLCBzbyB0aGF0IHdlIGNhbgo+ID4gPiA+IG1vcmUgZWFz aWx5IGJhY2twb3J0IHRoZSBmaXg/Cj4gPiA+IAo+ID4gPiBIaSBDYXNjYXJkbywKPiA+ID4gR2l2 ZW4gdGhhdCB0aGlzIGhhcyBiZWVuIGJyb2tlbiBvbiBBQkl2MiBzaW5jZSBmb3JldmVyLCBJIGRp ZG4ndCBib3RoZXIgCj4gPiA+IGZpeGluZyBpdC4gQnV0LCBJIGNhbiBzZWUgd2h5IHRoaXMgd291 bGQgYmUgYSBnb29kIHRoaW5nIHRvIGhhdmUgZm9yIAo+ID4gPiAtc3RhYmxlIGFuZCBleGlzdGlu ZyBkaXN0cm9zLiBIb3dldmVyLCB3aGlsZSB5b3VyIHBhdGNoIGJlbG93IG1heSBmaXggCj4gPiA+ IHRoZSBjcmFzaCB5b3UncmUgc2VlaW5nIG9uIHBwYzY0bGUsIGl0IGlzIG5vdCBzdWZmaWNpZW50 IC0tIHlvdSdsbCBuZWVkIAo+ID4gPiBjaGFuZ2VzIGluIGJwZl9qaXRfYXNtLlMgYXMgd2VsbC4K PiA+IAo+ID4gSGksIE5hdmVlbi4KPiA+IAo+ID4gQW55IHRpcHMgb24gaG93IHRvIGV4ZXJjaXNl IHBvc3NpYmxlIGlzc3VlcyB0aGVyZT8gT3Igd2hhdCBjaGFuZ2VzIHlvdSB0aGluawo+ID4gd291 bGQgYmUgc3VmZmljaWVudD8KPiAKPiBUaGUgY2FsbGluZyBjb252ZW50aW9uIGlzIGRpZmZlcmVu dCB3aXRoIEFCSXYyIGFuZCBzbyB3ZSdsbCBuZWVkIGNoYW5nZXMgCj4gaW4gYnBmX3Nsb3dfcGF0 aF9jb21tb24oKSBhbmQgc2tfbmVnYXRpdmVfY29tbW9uKCkuCj4gCj4gSG93ZXZlciwgcmF0aGVy IHRoYW4gZW5hYmxpbmcgY2xhc3NpYyBKSVQgZm9yIHBwYzY0bGUsIGFyZSB3ZSBiZXR0ZXIgb2Zm IAo+IGp1c3QgZGlzYWJsaW5nIGl0Pwo+IAo+IC0tLSBhL2FyY2gvcG93ZXJwYy9LY29uZmlnCj4g KysrIGIvYXJjaC9wb3dlcnBjL0tjb25maWcKPiBAQCAtMTI4LDcgKzEyOCw3IEBAIGNvbmZpZyBQ UEMKPiAgICAgICAgIHNlbGVjdCBJUlFfRk9SQ0VEX1RIUkVBRElORwo+ICAgICAgICAgc2VsZWN0 IEhBVkVfUkNVX1RBQkxFX0ZSRUUgaWYgU01QCj4gICAgICAgICBzZWxlY3QgSEFWRV9TWVNDQUxM X1RSQUNFUE9JTlRTCj4gLSAgICAgICBzZWxlY3QgSEFWRV9DQlBGX0pJVAo+ICsgICAgICAgc2Vs ZWN0IEhBVkVfQ0JQRl9KSVQgaWYgQ1BVX0JJR19FTkRJQU4KPiAgICAgICAgIHNlbGVjdCBIQVZF X0FSQ0hfSlVNUF9MQUJFTAo+ICAgICAgICAgc2VsZWN0IEFSQ0hfSEFWRV9OTUlfU0FGRV9DTVBY Q0hHCj4gICAgICAgICBzZWxlY3QgQVJDSF9IQVNfR0NPVl9QUk9GSUxFX0FMTAo+IAo+IAo+IE1p Y2hhZWwsCj4gTGV0IG1lIGtub3cgeW91ciB0aG91Z2h0cyBvbiB3aGV0aGVyIHlvdSBpbnRlbmQg dG8gdGFrZSB0aGlzIHBhdGNoIG9yIAo+IENhc2NhcmRvJ3MgcGF0Y2ggZm9yIC1zdGFibGUgYmVm b3JlIHRoZSBlQlBGIHBhdGNoZXMuIEkgY2FuIHJlZG8gbXkgCj4gcGF0Y2hlcyBhY2NvcmRpbmds eS4KCkNhbiBvbmUgb2YgeW91IHNlbmQgbWUgYSBwcm9wZXIgdmVyc2lvbiBvZiB0aGlzIHBhdGNo LCB3aXRoIGNoYW5nZSBsb2cgYW5kCnNpZ24tb2ZmIGV0Yy4KCmNoZWVycwoKX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KTGludXhwcGMtZGV2IG1haWxpbmcg bGlzdApMaW51eHBwYy1kZXZAbGlzdHMub3psYWJzLm9yZwpodHRwczovL2xpc3RzLm96bGFicy5v cmcvbGlzdGluZm8vbGludXhwcGMtZGV2