Save PG_compound or PG_head value in VMCOREINFO
Eric W. Biederman
ebiederm at xmission.com
Tue Nov 27 16:25:35 EST 2012
Petr Tesarik <ptesarik at suse.cz> writes:
> To allow filtering of huge pages, makedumpfile must be able to identify
> them in the dump. This can be done by checking for the appropriate
> page flag, so communicate its value to makedumpfile through the VMCOREINFO
I don't have any siginificant problems with exporting this information.
However that #ifddef looks nasty and confusing.
Does that #ifdef exist in the huge page code as well?
Can we always export both? Can we only export one?
What is the purpose of the #ifdef?
As it stands that looks like code that will figure out how to bitrot
if we just leave it sitting there.
> Signed-off-by: Petr Tesarik <ptesarik at suse.cz>
> kernel/kexec.c | 5 +++++
> 1 file changed, 5 insertions(+)
> --- a/kernel/kexec.c
> +++ b/kernel/kexec.c
> @@ -1511,6 +1511,11 @@ static int __init crash_save_vmcoreinfo_
> +#ifdef CONFIG_PAGEFLAGS_EXTENDED
> + VMCOREINFO_NUMBER(PG_head);
> + VMCOREINFO_NUMBER(PG_compound);
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