https://bugs.kde.org/show_bug.cgi?id=419562
Bug ID: 419562 Summary: PR_SET_PTRACER error with Ubuntu on WSL Product: valgrind Version: unspecified Platform: MS Windows OS: Linux Status: REPORTED Severity: normal Priority: NOR Component: general Assignee: jsew...@acm.org Reporter: e...@ozhiker.com Target Milestone: --- Created attachment 127224 --> https://bugs.kde.org/attachment.cgi?id=127224&action=edit Possible fix by falling back to alternate PR_SET_PTRACER call SUMMARY When running Ubuntu 18.04 on Windows-Subsystem-for-Linux (WSL), I have noticed the following error during every run of Valgrind: error calling PR_SET_PTRACER, vgdb might block STEPS TO REPRODUCE 1. Use Ubuntu 18.04 on WSL 2. Build Valgrind from git ./autogen.sh && ./configure && make -j8 --quiet check 3. Run valgrind against any program: VALGRIND_LIB=./.in_place VALGRIND_LIB_INNER=./.in_place/ ./coregrind/valgrind pwd OBSERVED RESULT error calling PR_SET_PTRACER, vgdb might block EXPECTED RESULT no error SOFTWARE/OS VERSIONS Windows: 10 (1909) 10.0.18363.720 Linux: Ubuntu 18.04 on WSL Valgrind: 3.16.0.GIT ADDITIONAL INFORMATION This is caused by a bug in noted in the following stack overflow: https://stackoverflow.com/questions/57206233/valgrind-showing-error-calling-pr-set-ptracer-vgdb-might-block It was logged with Microsoft as: https://github.com/microsoft/WSL/issues/3053 It has apparently been fixed in WSL build 17723: https://docs.microsoft.com/en-us/windows/wsl/release-notes#build-17723-fast However it seems that it has not yet reached Windows Update (despite my PC being at build 18363) The error comes from VG_(set_ptracer)() in coregrind/m_gdbserver/remote-utils.c It appears that the following call fails: ret = VG_(prctl) (PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0); But if the following alternate line is enabled, the call succeeds: ret = VG_(prctl) (PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0); I believe we could work around this by just failing-over from the first prctl to the second. I will submit a patch which does that. -- You are receiving this mail because: You are watching all bug changes.