From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id F0DBA3858C62; Thu, 18 May 2023 17:43:50 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org F0DBA3858C62 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1684431830; bh=TznGvx4iS6bGYaR9k8AJs8uVElAivfQH+EJc1QikOR0=; h=From:To:Subject:Date:In-Reply-To:References:From; b=gQyQiN43UyTmUj4HTFYkMOcp2UaR3Y6kfPZSSBpVCWLe+4prs2/WfgKURwY+muouk wMfmRUVHZ1usekO8I3r5+/re0NHlABmGggePnP8zq6n8DoFRCytwng+JwVJxN6ImL4 1zbTUa7At/1zobHBrVoM9BB3vSqhhvWVA+zCw4oc= From: "agentzh at gmail dot com" To: systemtap@sourceware.org Subject: [Bug runtime/30393] Lockdep error in _stp_ctl_work_callback()/wake_up_interruptible() on a fedora debug kernel Date: Thu, 18 May 2023 17:43:50 +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: agentzh at gmail dot com X-Bugzilla-Status: UNCONFIRMED 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 List-Id: https://sourceware.org/bugzilla/show_bug.cgi?id=3D30393 --- Comment #4 from agentzh --- Here's my best theory: a user process has grabbed the mm map lock, and in i= ts critical section, stap runtime's ctl work timer is fired; and inside the ctl work callback, stap calls wake_up_interruptible(), which may try to trigger scheduler context switches and hence that lockdep error "Illegal context sw= itch in RCU-bh read-side critical section!". __wake_up_common_lock() appears in the lockdep backtrace, which is indeed called from __wake_up(), which is wake_up_interruptible(). Furthermore, both _stp_request_exit and _stp_ctl_work_callback are in the lockdep backtrace. --=20 You are receiving this mail because: You are the assignee for the bug.=