PageAnon() always look at head page to check PAGE_MAPPING_ANON and tail page's page->mapping has just a poisoned data since commit 1c290f642101e6. If makedumpfile checks page->mapping of an compound tail page to distinguish anonymous page as usual, it must fail in newer kernel. So it's necessary to export OFFSET(page.compound_head) to avoid checking compound tail pages. Signed-off-by: Atsushi Kumagai <ats-kumagai at wm.jp.nec.com> --- kernel/kexec_core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c index 7c0b61d..4726999 100644 --- a/kernel/kexec_core.c +++ b/kernel/kexec_core.c @@ -1415,6 +1415,7 @@ static int __init crash_save_vmcoreinfo_init(void) VMCOREINFO_OFFSET(page, private); VMCOREINFO_OFFSET(page, compound_dtor); VMCOREINFO_OFFSET(page, compound_order); + VMCOREINFO_OFFSET(page, compound_head); VMCOREINFO_OFFSET(pglist_data, node_zones); VMCOREINFO_OFFSET(pglist_data, nr_zones); #ifdef CONFIG_FLAT_NODE_MEM_MAP -- 2.7.2
