From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 2269A3858410; Thu, 10 Mar 2022 13:25:56 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 2269A3858410 From: "gprocida at google dot com" To: libabigail@sourceware.org Subject: [Bug default/28954] New: add Linux Kernel symbol namespace support Date: Thu, 10 Mar 2022 13:25:55 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: libabigail X-Bugzilla-Component: default X-Bugzilla-Version: unspecified X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: gprocida at google dot com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: dodji at redhat dot com X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status bug_severity priority component assigned_to reporter cc target_milestone Message-ID: 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-BeenThere: libabigail@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Mailing list of the Libabigail project List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 10 Mar 2022 13:25:56 -0000 https://sourceware.org/bugzilla/show_bug.cgi?id=3D28954 Bug ID: 28954 Summary: add Linux Kernel symbol namespace support Product: libabigail Version: unspecified Status: UNCONFIRMED Severity: normal Priority: P2 Component: default Assignee: dodji at redhat dot com Reporter: gprocida at google dot com CC: libabigail at sourceware dot org Target Milestone: --- Hi. We have started to see Linux kernel symbol namespace changes break module loading, without being picked up by ABI monitoring beforehand. If a symbol has a namespace, then any module attempting to use it (run-time load check) must have imported (compile-time) the namespace. Load failure c= an be commuted to a warning but I doubt we would do that for Android. In terms of ABI monitoring, a change to a symbol's namespace should be repo= rted as an ABI diff. While it might also be nice to store the imported namespaces per module (at= the abg-corpus level), without also tracking undefined symbols this wouldn't al= low any automatic checking of kernel / module compatibility. Also, there is a compile-time check that does that anyway. We are trying to ensure that separately built kernel and modules will (continue to) work together. At a minimum we need the following: * new ELF symbol XML attribute (and possible documentation update) * new field in ELF symbol * symtab reader changes to populate this * XML writer change to print this * XML reader change to read this * categorisation of symbol namespace changes (probably the same as for CRCs) * symbol namespace diff generation / reporting I'm happy to start work on this, but would welcome any early feedback. References https://www.kernel.org/doc/html/latest/core-api/symbol-namespaces.html https://lwn.net/Articles/760045/ https://lpc.events/event/2/contributions/220/attachments/44/51/01._Symbol_N= amespaces__Plumbers_v2.pdf Giuliano. --=20 You are receiving this mail because: You are on the CC list for the bug.=