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| author | Michael Ellerman <mpe@ellerman.id.au> | 2016-09-15 15:11:59 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2016-09-19 10:53:56 +1000 |
| commit | 7de3b27bac47da9de08409df1d69664acbb72197 (patch) | |
| tree | 34c3d7f43012a3a5a686ce95c7d94d731b0dddb4 | |
| parent | bea2dccccfd47ef3f8612f1265f653f8e018d793 (diff) | |
| download | linux-stable-7de3b27bac47da9de08409df1d69664acbb72197.tar.gz linux-stable-7de3b27bac47da9de08409df1d69664acbb72197.tar.bz2 linux-stable-7de3b27bac47da9de08409df1d69664acbb72197.zip | |
powerpc: Ensure .mem(init|exit).text are within _stext/_etext
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 <mpe@ellerman.id.au>
Tested-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| -rw-r--r-- | arch/powerpc/kernel/vmlinux.lds.S | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index b5fba689fca6..b59d75e194a5 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -56,6 +56,8 @@ SECTIONS KPROBES_TEXT IRQENTRY_TEXT SOFTIRQENTRY_TEXT + MEM_KEEP(init.text) + MEM_KEEP(exit.text) #ifdef CONFIG_PPC32 *(.got1) |