From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <sourceware-bugzilla@sourceware.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 47CA83882077; Tue, 22 Aug 2023 15:27:00 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 47CA83882077
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org;
	s=default; t=1692718020;
	bh=1JCDJU0deu7NyNaPrOg1AGaKyHJ+kqEHaTtqp/8BcsY=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=LnhgOU5D6X2uy+YfutOc8tTWJYpbjOLu1lx3wCbkYXGXgnNgucxUGpwtMZf2x33xQ
	 6Lri3EzajfePh/dB5jFvaQ+of/y3ANG2uRoqwuorPY5/DXZbJ94L9QNCdDSK2agzHB
	 dOFMS1APpimpna1LIpIxyBEOh088cSwyJETtIgWY=
From: "wcohen at redhat dot com" <sourceware-bugzilla@sourceware.org>
To: systemtap@sourceware.org
Subject: [Bug runtime/30777] Systemtap modules unable to run on systemtap
 supporting Intel CET IBT
Date: Tue, 22 Aug 2023 15:26:59 +0000
X-Bugzilla-Reason: AssignedTo
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: systemtap
X-Bugzilla-Component: runtime
X-Bugzilla-Version: unspecified
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: wcohen at redhat dot com
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: attachments.created
Message-ID: <bug-30777-6586-0jGGFXwnKx@http.sourceware.org/bugzilla/>
In-Reply-To: <bug-30777-6586@http.sourceware.org/bugzilla/>
References: <bug-30777-6586@http.sourceware.org/bugzilla/>
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
List-Id: <systemtap.sourceware.org>

https://sourceware.org/bugzilla/show_bug.cgi?id=3D30777

--- Comment #2 from William Cohen <wcohen at redhat dot com> ---
Created attachment 15077
  --> https://sourceware.org/bugzilla/attachment.cgi?id=3D15077&action=3Ded=
it
A sample module demonstrating a workaround approach

The flippy_ibt is a really basic module that has surrounds the indirect call
with a ibt_save and ibt_restore operation.  To test out on a machine that
support IBT:

tar xvf flippy_ibt.tar.gz
cd flippy_ibt
make -C /usr/src/kernels/$(uname -r) M=3D$PWD V=3D2=20
sudo insmod flippy_ibt.ko
sudo rmmod flippy_ibt

You should see success (no trap for the missing ENDBR) in output of:

dmesg=20

One can check that the kernel IBT support is actually active with the same
module by installing with:

sudo insmod flippy_ibt.ko ibt_disable=3D0

You will see a message on the terminal about a segmentation fault and there
will be a trap  for the missing ENDBR in the output of dmesg.

That

--=20
You are receiving this mail because:
You are the assignee for the bug.=