From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 643C13858C78; Wed, 22 Nov 2023 15:02:20 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 643C13858C78 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1700665340; bh=d70mnYadKsGQAXyBdnYb9ZFqpERPYwA818YOi0sAMws=; h=From:To:Subject:Date:In-Reply-To:References:From; b=DfJdM3OQN6BukRnKVJe8ERkKzCRrbOjXTYpWspByYZTPFEcEBHMk++ETaf+7gw9Jd BHbOdelKVHwLtf+Gc5dgY4ilsmFeu4ns2JXjv7EeOVpuoryHxC4onO1b47BTfZ/vIY dZTbmP8WyeAhbBS9/bMU3OTv89Xrfov1h3Ayxh5o= From: "wcohen at redhat dot com" To: systemtap@sourceware.org Subject: [Bug runtime/31074] On aarch64 the systemtap.base/set_kernel.stp triggers "Unable to handle kernel paging request" Date: Wed, 22 Nov 2023 15:02:19 +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: ASSIGNED 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: bug_status 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=3D31074 William Cohen changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |ASSIGNED --- Comment #2 from William Cohen --- Yes, it looked like the value might NULL + offset for field. Added "-g -save-temps" to EXTRA_CFLAGS of the make file of the save /tmp/stap* to get= a better idea of what the compiler is generating for code and where things are located. for the get_buffer: adrp x3, .LANCHOR0 add x3, x3, :lo12:.LANCHOR0 add x3, x3, 568 mov x2, 512 mov x0, x3 mov w1, 0 .LVL175: .loc 23 1963 178 discriminator 1 view .LVU775 bl memset get_tracepoint (static tracepoint_table) .LVL489: .loc 27 127 36 view .LVU2068 adrp x1, .LANCHOR0 add x1, x1, :lo12:.LANCHOR0 add x1, x1, 1080 ldr x19, [x1, x0, lsl 3] One thought that crossed my mind is that the memset code is pretty optimized using cacheline zeroing for specific memset(x, 0, size) operations and migh= t be overrunning the end the static buffer into the static tracepoint_table as buffer is not aligned to cache boundaries. However, reducing the size of t= he get_buffer memset clearing didn't eliminate the problem. Thinking probably should add some diagnostics to the stp_tracepoint.c to ge= t a better understanding how tracepoint_table entries are getting corrupted. --=20 You are receiving this mail because: You are the assignee for the bug.=