On Wed 2016-01-20 17:03:23, Michael Ellerman wrote: > On Wed, 2016-01-06 at 15:17 +0100, Petr Mladek wrote: > > On Fri 2015-12-04 15:45:29, Torsten Duwe wrote: > > > Changes since v4: > > > * change comment style in entry_64.S to C89 > > > (nobody is using assembler syntax comments there). > > > * the bool function restore_r2 shouldn't return 2, > > > that's a little confusing. > > > * Test whether the compiler supports -mprofile-kernel > > > and only then define CC_USING_MPROFILE_KERNEL > > > * also make the return value of klp_check_compiler_support > > > depend on that. > > > > Note that there is still needed the extra patch from > > http://thread.gmane.org/gmane.linux.kernel/2093867/focus=2099603 > > to get the livepatching working. > > Sorry which extra patch? It was in an older reply and can be found at http://thread.gmane.org/gmane.linux.kernel/2093867/focus=2099603 > > Both ftrace with regs and live patching works for me with this patch > > set and the extra patch. So. for the whole patchset: > > > > Tested-by: Petr Mladek <pmladek@xxxxxxxx> > > Can you give me some more info on how you're testing it? What config options, > toolchain etc.? You need to fulfill all dependencies for CONFIG_LIVEPATCH, see kernel/livepatch/Kconfig. Please, find attached the config that that I used. I did the testing on PPC64LE with a kernel based on 4.4.0-rc8 using the attached config. I used the following stuff: $> gcc --version gcc (SUSE Linux) 4.8.5 Copyright (C) 2015 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $> rpm -q binutils binutils-2.25.0-13.1.ppc64le I tested it the following way: # booted the compiled kernel and printed the default cmdline $> cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-4.4.0-rc3-11-default+ root=UUID=... # tried function_graph tracer to check ftrace with regs echo function_graph >/sys/kernel/debug/tracing/current_tracer ; \ echo 1 >/sys/kernel/debug/tracing/tracing_on ; \ sleep 1 ; \ /usr/bin/ls /proc ; \ echo 0 >/sys/kernel/debug/tracing/tracing_on ; \ less /sys/kernel/debug/tracing/trace # loaded the patch and printed the patch cmdline $> modprobe livepatch-sample $> cat /proc/cmdline this has been live patched # tried to disable and enable the patch $> echo 0 > /sys/kernel/livepatch/livepatch_sample/enabled $> cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-4.4.0-rc3-11-default+ root=UUID=... $> echo 1 > /sys/kernel/livepatch/livepatch_sample/enabled $> cat /proc/cmdline this has been live patched # also checked messages $> dmesg | tail -n 4 [ 33.673057] livepatch: tainting kernel with TAINT_LIVEPATCH [ 33.673068] livepatch: enabling patch 'livepatch_sample' [ 1997.098257] livepatch: disabling patch 'livepatch_sample' [ 2079.696277] livepatch: enabling patch 'livepatch_sample' > For me the series doesn't even boot, even with livepatching disabled. I wonder if you have enabled CONFIG_FTRACE_STARTUP_TEST and if the ftrace with regs fails on your setup. Best Regards, Petr -- To unsubscribe from this list: send the line "unsubscribe live-patching" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
