On Wed, Nov 11, 2020 at 09:54:48PM +0800, Baoquan He wrote:
> On 11/11/20 at 09:27pm, chenzhou wrote:
> > Hi Baoquan,
> ...
> > >> #ifdef CONFIG_CRASH_DUMP
> > >> static int __init early_init_dt_scan_elfcorehdr(unsigned long node,
> > >> diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
> > >> index 1c0f3e02f731..c55cee290bbb 100644
> > >> --- a/arch/arm64/mm/mmu.c
> > >> +++ b/arch/arm64/mm/mmu.c
> > >> @@ -488,6 +488,10 @@ static void __init map_mem(pgd_t *pgdp)
> > >> */
> > >> memblock_mark_nomap(kernel_start, kernel_end - kernel_start);
> > >> #ifdef CONFIG_KEXEC_CORE
> > >> + if (crashk_low_res.end)
> > >> + memblock_mark_nomap(crashk_low_res.start,
> > >> + resource_size(&crashk_low_res));
> > >> +
> > >> if (crashk_res.end)
> > >> memblock_mark_nomap(crashk_res.start,
> > >> resource_size(&crashk_res));
> > >> diff --git a/kernel/crash_core.c b/kernel/crash_core.c
> > >> index d39892bdb9ae..cdef7d8c91a6 100644
> > >> --- a/kernel/crash_core.c
> > >> +++ b/kernel/crash_core.c
> > >> @@ -321,7 +321,7 @@ int __init parse_crashkernel_low(char *cmdline,
> > >>
> > >> int __init reserve_crashkernel_low(void)
> > >> {
> > >> -#ifdef CONFIG_X86_64
> > >> +#if defined(CONFIG_X86_64) || defined(CONFIG_ARM64)
> > > Not very sure if a CONFIG_64BIT checking is better.
> > If doing like this, there may be some compiling errors for other 64-bit
> > kernel, such as mips.
> > >
> > >> unsigned long long base, low_base = 0, low_size = 0;
> > >> unsigned long low_mem_limit;
> > >> int ret;
> > >> @@ -362,12 +362,14 @@ int __init reserve_crashkernel_low(void)
> > >>
> > >> crashk_low_res.start = low_base;
> > >> crashk_low_res.end = low_base + low_size - 1;
> > >> +#ifdef CONFIG_X86_64
> > >> insert_resource(&iomem_resource, &crashk_low_res);
> > >> +#endif
> > >> #endif
> > >> return 0;
> > >> }
> > >>
> > >> -#ifdef CONFIG_X86
> > >> +#if defined(CONFIG_X86) || defined(CONFIG_ARM64)
> > > Should we make this weak default so that we can remove the ARCH config?
> > The same as above, some arch may not support kdump, in that case,
> > compiling errors occur.
>
> OK, not sure if other people have better idea, oterwise, we can leave with
> it.
> Thanks for telling.
I think it would be better to have CONFIG_ARCH_WANT_RESERVE_CRASH_KERNEL
in arch/Kconfig and select this by X86 and ARM64.
Since reserve_crashkernel() implementations are quite similart on other
architectures as well, we can have more users of this later.
--
Sincerely yours,
Mike.
