On 02/18/21 at 03:31pm, Baoquan He wrote:
> On 01/30/21 at 03:10pm, Chen Zhou wrote:
> > We make the functions reserve_crashkernel[_low]() as generic for
> > x86 and arm64. Since reserve_crashkernel[_low]() implementations
> > are quite similar on other architectures as well, we can have more
> > users of this later.
> >
> > So have CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL in arch/Kconfig and
> > select this by X86 and ARM64.
> >
> > Suggested-by: Mike Rapoport <rppt@xxxxxxxxxx>
> > Suggested-by: Baoquan He <bhe@xxxxxxxxxx>
> > Signed-off-by: Chen Zhou <chenzhou10@xxxxxxxxxx>
> > ---
> > arch/Kconfig | 3 +++
> > arch/arm64/Kconfig | 1 +
> > arch/x86/Kconfig | 2 ++
> > kernel/crash_core.c | 7 ++-----
> > 4 files changed, 8 insertions(+), 5 deletions(-)
> >
> > diff --git a/arch/Kconfig b/arch/Kconfig
> > index 24862d15f3a3..0ca1ff5bb157 100644
> > --- a/arch/Kconfig
> > +++ b/arch/Kconfig
> > @@ -24,6 +24,9 @@ config KEXEC_ELF
> > config HAVE_IMA_KEXEC
> > bool
> >
> > +config ARCH_WANT_RESERVE_CRASH_KERNEL
> > + bool
> > +
> > config SET_FS
> > bool
> >
> > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> > index f39568b28ec1..09365c7ff469 100644
> > --- a/arch/arm64/Kconfig
> > +++ b/arch/arm64/Kconfig
> > @@ -82,6 +82,7 @@ config ARM64
> > select ARCH_WANT_FRAME_POINTERS
> > select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
> > select ARCH_WANT_LD_ORPHAN_WARN
> > + select ARCH_WANT_RESERVE_CRASH_KERNEL if KEXEC_CORE
> > select ARCH_HAS_UBSAN_SANITIZE_ALL
> > select ARM_AMBA
> > select ARM_ARCH_TIMER
> > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> > index 21f851179ff0..e6926fcb4a40 100644
> > --- a/arch/x86/Kconfig
> > +++ b/arch/x86/Kconfig
> > @@ -12,6 +12,7 @@ config X86_32
> > depends on !64BIT
> > # Options that are inherently 32-bit kernel only:
> > select ARCH_WANT_IPC_PARSE_VERSION
> > + select ARCH_WANT_RESERVE_CRASH_KERNEL if KEXEC_CORE
> > select CLKSRC_I8253
> > select CLONE_BACKWARDS
> > select GENERIC_VDSO_32
> > @@ -28,6 +29,7 @@ config X86_64
> > select ARCH_HAS_GIGANTIC_PAGE
> > select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
> > select ARCH_USE_CMPXCHG_LOCKREF
> > + select ARCH_WANT_RESERVE_CRASH_KERNEL if KEXEC_CORE
> > select HAVE_ARCH_SOFT_DIRTY
> > select MODULES_USE_ELF_RELA
> > select NEED_DMA_MAP_STATE
> > diff --git a/kernel/crash_core.c b/kernel/crash_core.c
> > index 8479be270c0b..2c5783985db5 100644
> > --- a/kernel/crash_core.c
> > +++ b/kernel/crash_core.c
> > @@ -320,9 +320,7 @@ int __init parse_crashkernel_low(char *cmdline,
> > * --------- Crashkernel reservation ------------------------------
> > */
> >
> > -#ifdef CONFIG_KEXEC_CORE
> > -
> > -#if defined(CONFIG_X86) || defined(CONFIG_ARM64)
> > +#ifdef CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL
> > static int __init reserve_crashkernel_low(void)
> > {
> > #ifdef CONFIG_64BIT
> > @@ -450,8 +448,7 @@ void __init reserve_crashkernel(void)
> > crashk_res.start = crash_base;
> > crashk_res.end = crash_base + crash_size - 1;
> > }
> > -#endif
> > -#endif /* CONFIG_KEXEC_CORE */
> > +#endif /* CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL */
>
> Why don't you move the dummy reserve_crashkernel() here too?
>
> #ifdef CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL
> #ifdef CONFIG_KEXEC_CORE
> ...
> '...the real crashkernel reservation code...'
> ...
> #else
> static void __init reserve_crashkernel(void)
> {
> }
> #endif
> #endif /* CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL */
>
> Like this, you don't need those two dummy reserve_crashkernel() in x86
> and arm64?
Sorry, I was wrong. It's impossible like this since
CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL is selected only if KEXEC_CORE is
true. Please ignore this comment.
