Re: [PATCH] s390/crash: Fix KEXEC_NOTE_BYTES definition

Dave Young
2017-06-09T02:29:04Z

On 06/09/17 at 10:17am, Xunlei Pang wrote:
> S390 KEXEC_NOTE_BYTES is not used by note_buf_t as before, which
> is now defined as follows:
> typedef u32 note_buf_t[CRASH_CORE_NOTE_BYTES/4];
> It was changed by the CONFIG_CRASH_CORE feature.
>
> This patch gets rid of all the old KEXEC_NOTE_BYTES stuff, and
> renames KEXEC_NOTE_BYTES to CRASH_CORE_NOTE_BYTES for S390.
>
> Fixes: 692f66f26a4c ("crash: move crashkernel parsing and vmcore related code under CONFIG_CRASH_CORE")
> Cc: Dave Young <dyoung@redhat.com>
> Cc: Dave Anderson <anderson@redhat.com>
> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
> Cc: Gustavo Luiz Duarte <gustavold@linux.vnet.ibm.com>
> Signed-off-by: Xunlei Pang <xlpang@redhat.com>
> ---
> arch/s390/include/asm/kexec.h | 2 +-
> include/linux/crash_core.h | 7 +++++++
> include/linux/kexec.h | 11 +----------
> 3 files changed, 9 insertions(+), 11 deletions(-)
>
> diff --git a/arch/s390/include/asm/kexec.h b/arch/s390/include/asm/kexec.h
> index 2f924bc..352deb8 100644
> --- a/arch/s390/include/asm/kexec.h
> +++ b/arch/s390/include/asm/kexec.h
> @@ -47,7 +47,7 @@
> * Seven notes plus zero note at the end: prstatus, fpregset, timer,
> * tod_cmp, tod_reg, control regs, and prefix
> */
> -#define KEXEC_NOTE_BYTES \
> +#define CRASH_CORE_NOTE_BYTES \
> (ALIGN(sizeof(struct elf_note), 4) * 8 + \
> ALIGN(sizeof("CORE"), 4) * 7 + \
> ALIGN(sizeof(struct elf_prstatus), 4) + \
> diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h
> index e9de6b4..dbc6e5c 100644
> --- a/include/linux/crash_core.h
> +++ b/include/linux/crash_core.h
> @@ -10,9 +10,16 @@
> #define CRASH_CORE_NOTE_NAME_BYTES ALIGN(sizeof(CRASH_CORE_NOTE_NAME), 4)
> #define CRASH_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
>
> +/*
> + * The per-cpu notes area is a list of notes terminated by a "NULL"
> + * note header. For kdump, the code in vmcore.c runs in the context
> + * of the second kernel to combine them into one note.
> + */
> +#ifndef CRASH_CORE_NOTE_BYTES
> #define CRASH_CORE_NOTE_BYTES ((CRASH_CORE_NOTE_HEAD_BYTES * 2) + \
> CRASH_CORE_NOTE_NAME_BYTES + \
> CRASH_CORE_NOTE_DESC_BYTES)
> +#endif
>
> #define VMCOREINFO_BYTES PAGE_SIZE
> #define VMCOREINFO_NOTE_NAME "VMCOREINFO"
> diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> index 3ea8275..133df03 100644
> --- a/include/linux/kexec.h
> +++ b/include/linux/kexec.h
> @@ -14,7 +14,6 @@
>
> #if !defined(__ASSEMBLY__)
>
> -#include <linux/crash_core.h>
> #include <asm/io.h>
>
> #include <uapi/linux/kexec.h>
> @@ -25,6 +24,7 @@
> #include <linux/ioport.h>
> #include <linux/module.h>
> #include <asm/kexec.h>
> +#include <linux/crash_core.h>
>
> /* Verify architecture specific macros are defined */
>
> @@ -63,15 +63,6 @@
> #define KEXEC_CORE_NOTE_NAME CRASH_CORE_NOTE_NAME
>
> /*
> - * The per-cpu notes area is a list of notes terminated by a "NULL"
> - * note header. For kdump, the code in vmcore.c runs in the context
> - * of the second kernel to combine them into one note.
> - */
> -#ifndef KEXEC_NOTE_BYTES
> -#define KEXEC_NOTE_BYTES CRASH_CORE_NOTE_BYTES
> -#endif

It is still not clear how does s390 use the crash_notes except this macro.
But from code point of view we do need to update this as well after the
crash_core splitting.

Acked-by: Dave Young <dyoung@redhat.com>

Thanks
Dave