From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13093 invoked by alias); 2 Nov 2018 20:51:56 -0000 Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org Received: (qmail 12974 invoked by uid 48); 2 Nov 2018 20:51:48 -0000 From: "me at serhei dot io" To: systemtap@sourceware.org Subject: [Bug bpf/23829] Bug introduced in bpf -base.cxx in git master Date: Fri, 02 Nov 2018 20:51:00 -0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: systemtap X-Bugzilla-Component: bpf X-Bugzilla-Version: unspecified X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: me at serhei dot io X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: systemtap at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2018-q4/txt/msg00074.txt.bz2 https://sourceware.org/bugzilla/show_bug.cgi?id=3D23829 --- Comment #6 from Serhei Makarov --- Thanks for that info. I've tested with bpf.h from kernel 4.8. Other defines aside from __BPF_FUNC_MAPPER and BPF_J{LT,LE,SLT,SLE} seem to be present. The build errors reported should be fixed in commits 3d9e0d2a5 (for _F form= at specifiers on 32-bit systems) and 8fb0cb4a (for undefined bpf.h symbols). Partly fixed by adding a fallback version of __BPF_FUNC_MAPPER and fallback defines for the new BPF_J(...) insn opcodes (these are recognized by the new embedded-code assembler; stapbpf backend already replaces these with older insns, so the code should work even on old kernel versions that do not supp= ort them). Let me know if the fixes work and I can close the bug, or if I need to refi= ne my workaround further. This exposes a deeper issue, in that SystemTap/BPF must be compiled against= a recent kernel version to generate modules that use BPF features from that version. This has also caused hiccups e.g. when building SystemTap RPM pack= ages in mockbuild on a kernel without eBPF support. Don't see an obvious workaro= und for this. --=20 You are receiving this mail because: You are the assignee for the bug.