[PATCH V2 2/3] mm/ptdump: Split effective_prot() into level specific callbacks
From: Anshuman Khandual <hidden>
Date: 2025-04-07 05:31:41
Also in:
linux-arm-kernel, linux-mm, linux-riscv, linux-s390, lkml
Subsystem:
memory management, memory management - core, the rest, x86 architecture (32-bit and 64-bit), x86 mm · Maintainers:
Andrew Morton, David Hildenbrand, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski, Peter Zijlstra
Last argument in effective_prot() is u64 assuming pxd_val() returned value (all page table levels) is 64 bit. pxd_val() is very platform specific and its type should not be assumed in generic MM. Split effective_prot() into individual page table level specific callbacks which accepts corresponding pxd_t argument instead and then the subscribing platform (only x86) just derive pxd_val() from the entries as required and proceed as earlier. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Paul Walmsley <redacted> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <redacted> Cc: Ingo Molnar <mingo@redhat.com> Cc: linux-kernel@vger.kernel.org Cc: linux-riscv@lists.infradead.org Cc: linux-mm@kvack.org Signed-off-by: Anshuman Khandual <redacted> --- arch/x86/mm/dump_pagetables.c | 32 +++++++++++++++++++++++++++++++- include/linux/ptdump.h | 6 +++++- mm/ptdump.c | 20 ++++++++++---------- 3 files changed, 46 insertions(+), 12 deletions(-)
diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
index 2e1c2d006ace..a4700ef6eb64 100644
--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c@@ -266,6 +266,32 @@ static void effective_prot(struct ptdump_state *pt_st, int level, u64 val) st->prot_levels[level] = effective; } +static void effective_prot_pte(struct ptdump_state *st, pte_t pte) +{ + effective_prot(st, 4, pte_val(pte)); +} + +static void effective_prot_pmd(struct ptdump_state *st, pmd_t pmd) +{ + effective_prot(st, 3, pmd_val(pmd)); +} + +static void effective_prot_pud(struct ptdump_state *st, pud_t pud) +{ + effective_prot(st, 2, pud_val(pud)); +} + +static void effective_prot_p4d(struct ptdump_state *st, p4d_t p4d) +{ + effective_prot(st, 1, p4d_val(p4d)); +} + +static void effective_prot_pgd(struct ptdump_state *st, pgd_t pgd) +{ + effective_prot(st, 0, pgd_val(pgd)); +} + + /* * This function gets called on a break in a continuous series * of PTE entries; the next one is different so we need to
@@ -416,7 +442,11 @@ bool ptdump_walk_pgd_level_core(struct seq_file *m, .note_page_p4d = note_page_p4d, .note_page_pgd = note_page_pgd, .note_page_flush = note_page_flush, - .effective_prot = effective_prot, + .effective_prot_pte = effective_prot_pte, + .effective_prot_pmd = effective_prot_pmd, + .effective_prot_pud = effective_prot_pud, + .effective_prot_p4d = effective_prot_p4d, + .effective_prot_pgd = effective_prot_pgd, .range = ptdump_ranges }, .level = -1,
diff --git a/include/linux/ptdump.h b/include/linux/ptdump.h
index 1c1eb1fae199..240bd3bff18d 100644
--- a/include/linux/ptdump.h
+++ b/include/linux/ptdump.h@@ -17,7 +17,11 @@ struct ptdump_state { void (*note_page_p4d)(struct ptdump_state *st, unsigned long addr, p4d_t p4d); void (*note_page_pgd)(struct ptdump_state *st, unsigned long addr, pgd_t pgd); void (*note_page_flush)(struct ptdump_state *st); - void (*effective_prot)(struct ptdump_state *st, int level, u64 val); + void (*effective_prot_pte)(struct ptdump_state *st, pte_t pte); + void (*effective_prot_pmd)(struct ptdump_state *st, pmd_t pmd); + void (*effective_prot_pud)(struct ptdump_state *st, pud_t pud); + void (*effective_prot_p4d)(struct ptdump_state *st, p4d_t p4d); + void (*effective_prot_pgd)(struct ptdump_state *st, pgd_t pgd); const struct ptdump_range *range; };
diff --git a/mm/ptdump.c b/mm/ptdump.c
index 706cfc19439b..9374f29cdc6f 100644
--- a/mm/ptdump.c
+++ b/mm/ptdump.c@@ -38,8 +38,8 @@ static int ptdump_pgd_entry(pgd_t *pgd, unsigned long addr, return note_kasan_page_table(walk, addr); #endif - if (st->effective_prot) - st->effective_prot(st, 0, pgd_val(val)); + if (st->effective_prot_pgd) + st->effective_prot_pgd(st, val); if (pgd_leaf(val)) { st->note_page_pgd(st, addr, val);
@@ -61,8 +61,8 @@ static int ptdump_p4d_entry(p4d_t *p4d, unsigned long addr, return note_kasan_page_table(walk, addr); #endif - if (st->effective_prot) - st->effective_prot(st, 1, p4d_val(val)); + if (st->effective_prot_p4d) + st->effective_prot_p4d(st, val); if (p4d_leaf(val)) { st->note_page_p4d(st, addr, val);
@@ -84,8 +84,8 @@ static int ptdump_pud_entry(pud_t *pud, unsigned long addr, return note_kasan_page_table(walk, addr); #endif - if (st->effective_prot) - st->effective_prot(st, 2, pud_val(val)); + if (st->effective_prot_pud) + st->effective_prot_pud(st, val); if (pud_leaf(val)) { st->note_page_pud(st, addr, val);
@@ -106,8 +106,8 @@ static int ptdump_pmd_entry(pmd_t *pmd, unsigned long addr, return note_kasan_page_table(walk, addr); #endif - if (st->effective_prot) - st->effective_prot(st, 3, pmd_val(val)); + if (st->effective_prot_pmd) + st->effective_prot_pmd(st, val); if (pmd_leaf(val)) { st->note_page_pmd(st, addr, val); walk->action = ACTION_CONTINUE;
@@ -122,8 +122,8 @@ static int ptdump_pte_entry(pte_t *pte, unsigned long addr, struct ptdump_state *st = walk->private; pte_t val = ptep_get_lockless(pte); - if (st->effective_prot) - st->effective_prot(st, 4, pte_val(val)); + if (st->effective_prot_pte) + st->effective_prot_pte(st, val); st->note_page_pte(st, addr, val);
--
2.25.1