Re: [RFC v2 3/6] crash hp: definitions and prototype changes

From: Baoquan He
Date: Wed Jan 19 2022 - 03:26:02 EST


On 01/19/22 at 04:23pm, Baoquan He wrote:
> On 12/07/21 at 02:52pm, Eric DeVolder wrote:
> > This change adds members to struct kimage to facilitate crash
> > hotplug support.
> >
> > This change also defines crash hotplug events and associated
> > prototypes.
> >
> > Signed-off-by: Eric DeVolder <eric.devolder@xxxxxxxxxx>
> > ---
> > include/linux/kexec.h | 21 +++++++++++++++++++--
> > 1 file changed, 19 insertions(+), 2 deletions(-)
> >
> > diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> > index 0c994ae37729..068f853f1c65 100644
> > --- a/include/linux/kexec.h
> > +++ b/include/linux/kexec.h
> > @@ -221,8 +221,9 @@ struct crash_mem {
> > extern int crash_exclude_mem_range(struct crash_mem *mem,
> > unsigned long long mstart,
> > unsigned long long mend);
> > -extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
> > - void **addr, unsigned long *sz);
> > +extern int crash_prepare_elf64_headers(struct kimage *image,
> > + struct crash_mem *mem, int kernel_map,
> > + void **addr, unsigned long *sz);
> > #endif /* CONFIG_KEXEC_FILE */
> >
> > #ifdef CONFIG_KEXEC_ELF
> > @@ -299,6 +300,13 @@ struct kimage {
> >
> > /* Information for loading purgatory */
> > struct purgatory_info purgatory_info;
> > +
> > +#ifdef CONFIG_CRASH_HOTPLUG
> > + bool hotplug_event;
> > + int offlinecpu;
> > + bool elf_index_valid;
> > + int elf_index;
>
> Do we really need elf_index_valid? Can we initialize elf_index to , e.g '-1',
> then check if the value is valid?

Sorry, please ignore this one, I will add this comment in v3 thread.

>
> > +#endif
> > #endif
> >
> > #ifdef CONFIG_IMA_KEXEC
> > @@ -315,6 +323,15 @@ struct kimage {
> > unsigned long elf_load_addr;
> > };
> >
> > +#ifdef CONFIG_CRASH_HOTPLUG
> > +void arch_crash_hotplug_handler(struct kimage *image,
> > + unsigned int hp_action, unsigned long a, unsigned long b);
> > +#define KEXEC_CRASH_HP_REMOVE_CPU 0
> > +#define KEXEC_CRASH_HP_ADD_CPU 1
> > +#define KEXEC_CRASH_HP_REMOVE_MEMORY 2
> > +#define KEXEC_CRASH_HP_ADD_MEMORY 3
> > +#endif /* CONFIG_CRASH_HOTPLUG */
> > +
> > /* kexec interface functions */
> > extern void machine_kexec(struct kimage *image);
> > extern int machine_kexec_prepare(struct kimage *image);
> > --
> > 2.27.0
> >
>