Public bug reported: ---Problem Description--- This is a bug report for focal.
Valgrind, including version 3.16, mishandles the L field of the sync instruction. More details are available at: https://bugs.kde.org/show_bug.cgi?id=422677 This is a request to backport the following Valgrind patch from upstream: commit fb6f7abcbc92506d302fb18a2c5fc853d2929248 Author: Carl Love <c...@us.ibm.com> Date: Tue Jun 9 10:42:03 2020 -0500 Power PC Fix extraction of the L field for sync instruction The L field is currently a two bit[22:21] field in ISA 3.0. The size of the L field has changed over time. Currently the ISA 3.0 Valgrind sync instruction support code sets the flag_L for the instruction L field to a five bit value that includes bits that are marked reserved the sync instruction. This patch fixes the issue for ISA 3.0 to only setting flag_L the specified two bits. Valgrind bugzilla: https://bugs.kde.org/show_bug.cgi?id=422677 Contact Information = Tulio Magno/tul...@linux.ibm.com ---uname output--- N/A Machine Type = Reproducible on all POWER8 and POWER9 servers ---Debugger--- A debugger is not configured ---Steps to Reproduce--- $ cat test-sync.c #define __SYNC(l) ".long (0x7c0004AC | ((" #l ") << 21))" int main () { asm volatile(__SYNC(4) : : : "memory"); } $ gcc test-sync.c && valgrind --tool=none ./a.out ==150073== Nulgrind, the minimal Valgrind tool ==150073== Copyright (C) 2002-2017, and GNU GPL'd, by Nicholas Nethercote. ==150073== Using Valgrind-3.13.0 and LibVEX; rerun with -h for copyright info ==150073== Command: ./a.out ==150073== dis_memsync(ppc)(sync/lwsync,flag_L) disInstr(ppc): unhandled instruction: 0x7C8004AC primary 31(0x1F), secondary 1196(0x4AC) ==150073== valgrind: Unrecognised instruction at address 0x180788. ==150073== at 0x180788: main (in /home/tuliom/tmp/a.out) ==150073== Your program just tried to execute an instruction that Valgrind ==150073== did not recognise. ... Userspace tool common name: Valgrind The userspace tool has the following bit modes: 64-bit Userspace deb: valgrind Userspace tool obtained from project website: na ** Affects: ubuntu-power-systems Importance: Undecided Status: New ** Affects: valgrind (Ubuntu) Importance: Undecided Assignee: Ubuntu on IBM Power Systems Bug Triage (ubuntu-power-triage) Status: New ** Tags: architecture-ppc64le bugnameltc-186878 severity-medium targetmilestone-inin20041 ** Tags added: architecture-ppc64le bugnameltc-186878 severity-medium targetmilestone-inin20041 ** Changed in: ubuntu Assignee: (unassigned) => Ubuntu on IBM Power Systems Bug Triage (ubuntu-power-triage) ** Package changed: ubuntu => valgrind (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1887974 Title: [20.04] Valgrind: PPC sync instruction L field should only be 2 bits in ISA 3.0 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1887974/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs