On Thu, 2016-15-09 at 05:11:59 UTC, Michael Ellerman wrote: > In our linker script we open code the list of text sections, because we > need to include the __ftr_alt sections, which are arch-specific. > > This means we can't use TEXT_TEXT as defined in vmlinux.lds.h, and so we > don't have the MEM_KEEP() logic for memory hotplug sections. > > If we build the kernel with the gold linker, and with CONFIG_MEMORY_HOTPLUG=y, > we see that functions marked __meminit can end up outside of the > _stext/_etext range, and also outside of _sinittext/_einittext, eg: > > c000000000000000 T _stext > c0000000009e0000 A _etext > c0000000009e3f18 T hash__vmemmap_create_mapping > c000000000ca0000 T _sinittext > c000000000d00844 T _einittext > > This causes them to not be recognised as text by is_kernel_text(), and > prevents them being patched by jump_label (and presumably ftrace/kprobes > etc.). > > Fix it by adding MEM_KEEP() directives, mirroring what TEXT_TEXT does. > > This isn't a problem when CONFIG_MEMORY_HOTPLUG=n, because we use the > standard INIT_TEXT_SECTION() and EXIT_TEXT macros from vmlinux.lds.h. > > Signed-off-by: Michael Ellerman <m...@ellerman.id.au> > Tested-by: Anton Blanchard <an...@samba.org>
Applied to powerpc next. https://git.kernel.org/powerpc/c/7de3b27bac47da9de08409df1d cheers
