On 13/10/16 13:25, Nicholas Piggin wrote: > On Wed, 12 Oct 2016 18:35:21 +1100 > Balbir Singh <bsinghar...@gmail.com> wrote: > >> On 12/10/16 17:57, Nicholas Piggin wrote: >>> This adds a config option that can help exercise the case when >>> the kernel is not running at PAGE_OFFSET. >>> >>> Signed-off-by: Nicholas Piggin <npig...@gmail.com> >>> --- >>> arch/powerpc/Kconfig | 9 +++++++++ >>> arch/powerpc/kernel/head_64.S | 4 ++++ >>> arch/powerpc/kernel/setup-common.c | 3 +++ >>> 3 files changed, 16 insertions(+) >>> >>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig >>> index 65fba4c..5d43cb8 100644 >>> --- a/arch/powerpc/Kconfig >>> +++ b/arch/powerpc/Kconfig >>> @@ -478,6 +478,15 @@ config RELOCATABLE >>> setting can still be useful to bootwrappers that need to know the >>> load address of the kernel (eg. u-boot/mkimage). >>> >>> +config RELOCATABLE_TEST >>> + bool "Test relocatable kernel" >>> + depends on (PPC64 && RELOCATABLE) >>> + default n >>> + help >>> + This runs the relocatable kernel at the address it was initially >>> + loaded at, which tends to be non-zero and therefore test the >>> + relocation code. >>> + >>> config CRASH_DUMP >>> bool "Build a kdump crash kernel" >>> depends on PPC64 || 6xx || FSL_BOOKE || (44x && !SMP) >>> diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S >>> index 79da0641..bc9ceac 100644 >>> --- a/arch/powerpc/kernel/head_64.S >>> +++ b/arch/powerpc/kernel/head_64.S >>> @@ -111,8 +111,12 @@ __secondary_hold_acknowledge: >>> .globl __run_at_load >>> __run_at_load: >>> DEFINE_FIXED_SYMBOL(__run_at_load) >>> +#ifdef CONFIG_RELOCATABLE_TEST >>> + .long 0x1 /* Test relocation, do not relocate to 0 */ >>> +#else >>> .long 0x72756e30 /* "run0" -- relocate to 0 by default */ >>> #endif >>> +#endif >> >> Could we do something like >> >> config RELOCATION_VALUE >> default 0x72756e30 >> default 1 if CONFIG_RELOCTABLE_TEST >> >> and then get >> >> .long CONFIG_RELOCATION_VALUE > > Normally I'm up for reducing ifdefs in S and c files, but in this case > I'm not sure. I like being able to see the two possible values in the > source. I don't really mind though. If you or Michael feel strongly, I'm > happy to change it. >
I guess it depends, for me parsing two .long's under #ifdef seems a little more work than a .long with a constant depending on the configuration. I don't feel too strongly about it either Balbir Singh.
