On Tue 2016-01-26 11:50:25, Miroslav Benes wrote: > > [ added Petr to CC list ] > > On Mon, 25 Jan 2016, Torsten Duwe wrote: > > > * create the appropriate files+functions > > arch/powerpc/include/asm/livepatch.h > > klp_check_compiler_support, > > klp_arch_set_pc > > arch/powerpc/kernel/livepatch.c with a stub for > > klp_write_module_reloc > > This is architecture-independent work in progress. > > * introduce a fixup in arch/powerpc/kernel/entry_64.S > > for local calls that are becoming global due to live patching. > > And of course do the main KLP thing: return to a maybe different > > address, possibly altered by the live patching ftrace op. > > > > Signed-off-by: Torsten Duwe <duwe@xxxxxxx> > > Hi, > > I have a few questions... > > We still need Petr's patch from [1] to make livepatch work, right? Could > you, please, add it to this patch set to make it self-sufficient? > > Second, what is the situation with mcount prologue between gcc < 6 and > gcc-6? Are there only 12 bytes in gcc-6 prologue? If yes, we need to > change Petr's patch to make it more general and to be able to cope with > different prologues. This is unfortunate. Either way, please mention it > somewhere in a changelog. I am going to update the extra patch. There is an idea to detect the offset during build by scrips/recordmcount. This tool looks for the ftrace locations. The offset should always be a constant that depends on the used architecture, compiler, and compiler flags. The tool is called post build. We might need to pass the constant as a symbol added to the binary. The tool already adds some symbols. 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
