* Required for kernel 6.9
Kernel commit d99e3140a4d3 ("mm: turn folio_test_hugetlb into a
PageType") moved the PG_hugetlb flag from folio._flags_1 into
page._mapcount and introduced NUMBER(PAGE_HUGETLB_MAPCOUNT_VALUE) entry
into vmcoreinfo.
Without the patch, "makedumpfile -d 8" cannot exclude hugetlb pages.
Signed-off-by: Kazuhito Hagio <k-hagio-ab@xxxxxxx>
---
makedumpfile.c | 22 ++++++++++++++++++++--
makedumpfile.h | 3 +++
2 files changed, 23 insertions(+), 2 deletions(-)
diff --git a/makedumpfile.c b/makedumpfile.c
index d7f1dd41d2ca..a6cadc9092c9 100644
--- a/makedumpfile.c
+++ b/makedumpfile.c
@@ -2975,6 +2975,7 @@ read_vmcoreinfo(void)
READ_SRCFILE("pud_t", pud_t);
READ_NUMBER("PAGE_BUDDY_MAPCOUNT_VALUE", PAGE_BUDDY_MAPCOUNT_VALUE);
+ READ_NUMBER("PAGE_HUGETLB_MAPCOUNT_VALUE", PAGE_HUGETLB_MAPCOUNT_VALUE);
READ_NUMBER("PAGE_OFFLINE_MAPCOUNT_VALUE", PAGE_OFFLINE_MAPCOUNT_VALUE);
READ_NUMBER("phys_base", phys_base);
READ_NUMBER("KERNEL_IMAGE_SIZE", KERNEL_IMAGE_SIZE);
@@ -6510,6 +6511,9 @@ __exclude_unnecessary_pages(unsigned long mem_map,
_count = UINT(pcache + OFFSET(page._refcount));
mapping = ULONG(pcache + OFFSET(page.mapping));
+ if (OFFSET(page._mapcount) != NOT_FOUND_STRUCTURE)
+ _mapcount = UINT(pcache + OFFSET(page._mapcount));
+
compound_order = 0;
compound_dtor = 0;
/*
@@ -6520,6 +6524,22 @@ __exclude_unnecessary_pages(unsigned long mem_map,
if ((index_pg < PGMM_CACHED - 1) && isCompoundHead(flags)) {
unsigned char *addr = pcache + SIZE(page);
+ /*
+ * Linux 6.9 and later kernels use _mapcount value for hugetlb pages.
+ * See kernel commit d99e3140a4d3.
+ */
+ if (NUMBER(PAGE_HUGETLB_MAPCOUNT_VALUE) != NOT_FOUND_NUMBER) {
+ unsigned long _flags_1 = ULONG(addr + OFFSET(page.flags));
+ unsigned int PG_hugetlb = ~NUMBER(PAGE_HUGETLB_MAPCOUNT_VALUE);
+
+ compound_order = _flags_1 & 0xff;
+
+ if ((_mapcount & (PAGE_TYPE_BASE | PG_hugetlb)) == PAGE_TYPE_BASE)
+ compound_dtor = IS_HUGETLB;
+
+ goto check_order;
+ }
+
/*
* Linux 6.6 and later. Kernels that have PG_hugetlb should also
* have the compound order in the low byte of folio._flags_1.
@@ -6564,8 +6584,6 @@ check_order:
if (OFFSET(page.compound_head) != NOT_FOUND_STRUCTURE)
compound_head = ULONG(pcache + OFFSET(page.compound_head));
- if (OFFSET(page._mapcount) != NOT_FOUND_STRUCTURE)
- _mapcount = UINT(pcache + OFFSET(page._mapcount));
if (OFFSET(page.private) != NOT_FOUND_STRUCTURE)
private = ULONG(pcache + OFFSET(page.private));
diff --git a/makedumpfile.h b/makedumpfile.h
index 75b66ceaba21..f08c49fc73be 100644
--- a/makedumpfile.h
+++ b/makedumpfile.h
@@ -165,6 +165,8 @@ test_bit(int nr, unsigned long addr)
#define isAnon(mapping, flags) (((unsigned long)mapping & PAGE_MAPPING_ANON) != 0 \
&& !isSlab(flags))
+#define PAGE_TYPE_BASE (0xf0000000)
+
#define PTOB(X) (((unsigned long long)(X)) << PAGESHIFT())
#define BTOP(X) (((unsigned long long)(X)) >> PAGESHIFT())
@@ -2255,6 +2257,7 @@ struct number_table {
long PG_hugetlb;
long PAGE_BUDDY_MAPCOUNT_VALUE;
+ long PAGE_HUGETLB_MAPCOUNT_VALUE;
long PAGE_OFFLINE_MAPCOUNT_VALUE;
long SECTION_SIZE_BITS;
long MAX_PHYSMEM_BITS;
--
2.31.1
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