Provide a Kconfig option indicating if note_page can be called for
intermediate page directories during ptdump.
Signed-off-by: Maxwell Bland <mbland@xxxxxxxxxxxx>
---
mm/Kconfig.debug | 8 ++++++++
mm/ptdump.c | 26 ++++++++++++++++++--------
2 files changed, 26 insertions(+), 8 deletions(-)
diff --git a/mm/Kconfig.debug b/mm/Kconfig.debug
index afc72fde0f03..41071539bf9e 100644
--- a/mm/Kconfig.debug
+++ b/mm/Kconfig.debug
@@ -201,6 +201,14 @@ config PTDUMP_DEBUGFS
If in doubt, say N.
+config ARCH_SUPPORTS_NON_LEAF_PTDUMP
+ bool "Include intermediate directory entries in pagetable dumps"
+ help
+ Enable the inclusion of intermediate page directory entries in calls
+ to the ptdump API. Once an architecture defines correct ptdump
+ behavior for PGD, PUD, P4D, and PMD entries, this config can be
+ selected.
+
config HAVE_DEBUG_KMEMLEAK
bool
diff --git a/mm/ptdump.c b/mm/ptdump.c
index 106e1d66e9f9..3c8eea232282 100644
--- a/mm/ptdump.c
+++ b/mm/ptdump.c
@@ -26,6 +26,11 @@ static inline int note_kasan_page_table(struct mm_walk *walk,
}
#endif
+static inline bool has_non_leaf_ptdump(void)
+{
+ return IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP);
+}
+
static int ptdump_pgd_entry(pgd_t *pgd, unsigned long addr,
unsigned long next, struct mm_walk *walk)
{
@@ -41,10 +46,11 @@ static int ptdump_pgd_entry(pgd_t *pgd, unsigned long addr,
if (st->effective_prot)
st->effective_prot(st, 0, pgd_val(val));
- if (pgd_leaf(val)) {
+ if (has_non_leaf_ptdump() || pgd_leaf(val))
st->note_page(st, addr, 0, pgd_val(val));
+
+ if (pgd_leaf(val))
walk->action = ACTION_CONTINUE;
- }
return 0;
}
@@ -64,10 +70,11 @@ static int ptdump_p4d_entry(p4d_t *p4d, unsigned long addr,
if (st->effective_prot)
st->effective_prot(st, 1, p4d_val(val));
- if (p4d_leaf(val)) {
+ if (has_non_leaf_ptdump() || p4d_leaf(val))
st->note_page(st, addr, 1, p4d_val(val));
+
+ if (p4d_leaf(val))
walk->action = ACTION_CONTINUE;
- }
return 0;
}
@@ -87,10 +94,11 @@ static int ptdump_pud_entry(pud_t *pud, unsigned long addr,
if (st->effective_prot)
st->effective_prot(st, 2, pud_val(val));
- if (pud_leaf(val)) {
+ if (has_non_leaf_ptdump() || pud_leaf(val))
st->note_page(st, addr, 2, pud_val(val));
+
+ if (pud_leaf(val))
walk->action = ACTION_CONTINUE;
- }
return 0;
}
@@ -108,10 +116,12 @@ static int ptdump_pmd_entry(pmd_t *pmd, unsigned long addr,
if (st->effective_prot)
st->effective_prot(st, 3, pmd_val(val));
- if (pmd_leaf(val)) {
+
+ if (has_non_leaf_ptdump() || pmd_leaf(val))
st->note_page(st, addr, 3, pmd_val(val));
+
+ if (pmd_leaf(val))
walk->action = ACTION_CONTINUE;
- }
return 0;
}
--
2.43.0
