[ 324.182366] livepatch: kernel.ftrace_enabled = 1 [ 324.242695] ===== TEST: livepatch interaction with ftrace_enabled sysctl ===== [ 324.303935] livepatch: kernel.ftrace_enabled = 0 [ 324.305583] % modprobe test_klp_livepatch [ 324.389574] livepatch: enabling patch 'test_klp_livepatch' [ 324.390398] livepatch: 'test_klp_livepatch': initializing patching transition [ 324.390646] livepatch: failed to register ftrace handler for function 'cmdline_proc_show' (-16) [ 324.392007] livepatch: failed to patch object 'vmlinux' [ 324.392772] livepatch: failed to enable patch 'test_klp_livepatch' [ 324.393675] livepatch: 'test_klp_livepatch': canceling patching transition, going to unpatch [ 324.393683] livepatch: 'test_klp_livepatch': completing unpatching transition [ 324.394284] livepatch: 'test_klp_livepatch': unpatching complete [ 324.435901] modprobe: ERROR: could not insert 'test_klp_livepatch': Device or resource busy [ 324.497020] livepatch: kernel.ftrace_enabled = 1 [ 324.601006] % modprobe test_klp_livepatch [ 324.676777] livepatch: enabling patch 'test_klp_livepatch' [ 324.677633] livepatch: 'test_klp_livepatch': initializing patching transition [ 324.683435] livepatch: 'test_klp_livepatch': starting patching transition [ 324.685102] livepatch: 'test_klp_livepatch': completing patching transition [ 324.685220] livepatch: 'test_klp_livepatch': patching complete [ 324.818325] livepatch: sysctl: setting key "kernel.ftrace_enabled": Device or resource busy [ 324.852058] % echo 0 > /sys/kernel/livepatch/test_klp_livepatch/enabled [ 324.853671] livepatch: 'test_klp_livepatch': initializing unpatching transition [ 324.853749] livepatch: 'test_klp_livepatch': starting unpatching transition [ 326.252509] livepatch: 'test_klp_livepatch': completing unpatching transition [ 326.279256] livepatch: 'test_klp_livepatch': unpatching complete [ 326.405310] % rmmod test_klp_livepatch