[PATCH 5/5 RESEND] ptdump: add state parameter for non-leaf callback

From: Maxwell Bland <hidden>
Date: 2024-04-16 17:25:48
Also in: linux-arm-kernel, linux-mm, linux-riscv, linux-s390, lkml
Subsystem: arm64 port (aarch64 architecture), linux for powerpc (32-bit and 64-bit), memory management, memory management - core, risc-v architecture, s390 architecture, the rest, x86 architecture (32-bit and 64-bit), x86 mm · Maintainers: Catalin Marinas, Will Deacon, Madhavan Srinivasan, Michael Ellerman, Andrew Morton, David Hildenbrand, Paul Walmsley, Palmer Dabbelt, Albert Ou, Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski, Peter Zijlstra

ptdump can now note non-leaf descriptor entries, a useful addition for
debugging table descriptor permissions when working on related code

Signed-off-by: Maxwell Bland <redacted>
---
 arch/arm64/mm/ptdump.c          |  6 ++++--
 arch/powerpc/mm/ptdump/ptdump.c |  2 ++
 arch/riscv/mm/ptdump.c          |  6 ++++--
 arch/s390/mm/dump_pagetables.c  |  6 ++++--
 arch/x86/mm/dump_pagetables.c   |  3 ++-
 include/linux/ptdump.h          |  1 +
 mm/ptdump.c                     | 13 +++++++++++++
 7 files changed, 30 insertions(+), 7 deletions(-)

diff --git a/arch/arm64/mm/ptdump.c b/arch/arm64/mm/ptdump.c
index 796231a4fd63..1a6f4a3513e5 100644
--- a/arch/arm64/mm/ptdump.c
+++ b/arch/arm64/mm/ptdump.c

@@ -299,7 +299,8 @@ void ptdump_walk(struct seq_file *s, struct ptdump_info *info)
 			.range = (struct ptdump_range[]){
 				{info->base_addr, end},
 				{0, 0}
-			}
+			},
+			.note_non_leaf = false
 		}
 	};

@@ -335,7 +336,8 @@ bool ptdump_check_wx(void)
 			.range = (struct ptdump_range[]) {
 				{_PAGE_OFFSET(vabits_actual), ~0UL},
 				{0, 0}
-			}
+			},
+			.note_non_leaf = false
 		}
 	};

diff --git a/arch/powerpc/mm/ptdump/ptdump.c b/arch/powerpc/mm/ptdump/ptdump.c
index 9dc239967b77..89e673f5fd3d 100644
--- a/arch/powerpc/mm/ptdump/ptdump.c
+++ b/arch/powerpc/mm/ptdump/ptdump.c

@@ -307,6 +307,7 @@ static int ptdump_show(struct seq_file *m, void *v)
 		.ptdump = {
 			.note_page = note_page,
 			.range = ptdump_range,
+			.note_non_leaf = false
 		}
 	};

@@ -340,6 +341,7 @@ bool ptdump_check_wx(void)
 		.ptdump = {
 			.note_page = note_page,
 			.range = ptdump_range,
+			.note_non_leaf = false
 		}
 	};

diff --git a/arch/riscv/mm/ptdump.c b/arch/riscv/mm/ptdump.c
index 1289cc6d3700..b355633afcaf 100644
--- a/arch/riscv/mm/ptdump.c
+++ b/arch/riscv/mm/ptdump.c

@@ -328,7 +328,8 @@ static void ptdump_walk(struct seq_file *s, struct ptd_mm_info *pinfo)
 			.range = (struct ptdump_range[]) {
 				{pinfo->base_addr, pinfo->end},
 				{0, 0}
-			}
+			},
+			.note_non_leaf = false
 		}
 	};

@@ -350,7 +351,8 @@ bool ptdump_check_wx(void)
 			.range = (struct ptdump_range[]) {
 				{KERN_VIRT_START, ULONG_MAX},
 				{0, 0}
-			}
+			},
+			.note_non_leaf = false
 		}
 	};

diff --git a/arch/s390/mm/dump_pagetables.c b/arch/s390/mm/dump_pagetables.c
index ffd07ed7b4af..6468cfd53e2a 100644
--- a/arch/s390/mm/dump_pagetables.c
+++ b/arch/s390/mm/dump_pagetables.c

@@ -200,7 +200,8 @@ bool ptdump_check_wx(void)
 			.range = (struct ptdump_range[]) {
 				{.start = 0, .end = max_addr},
 				{.start = 0, .end = 0},
-			}
+			},
+			.note_non_leaf = false
 		},
 		.seq = NULL,
 		.level = -1,

@@ -239,7 +240,8 @@ static int ptdump_show(struct seq_file *m, void *v)
 			.range = (struct ptdump_range[]) {
 				{.start = 0, .end = max_addr},
 				{.start = 0, .end = 0},
-			}
+			},
+			.note_non_leaf = false
 		},
 		.seq = m,
 		.level = -1,

diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
index 89079ea73e65..43f00dfb955f 100644
--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c

@@ -380,7 +380,8 @@ bool ptdump_walk_pgd_level_core(struct seq_file *m,
 		.ptdump = {
 			.note_page	= note_page,
 			.effective_prot = effective_prot,
-			.range		= ptdump_ranges
+			.range		= ptdump_ranges,
+			.note_non_leaf  = false
 		},
 		.level = -1,
 		.to_dmesg	= dmesg,

diff --git a/include/linux/ptdump.h b/include/linux/ptdump.h
index 8dbd51ea8626..b3e793a5c77f 100644
--- a/include/linux/ptdump.h
+++ b/include/linux/ptdump.h

@@ -16,6 +16,7 @@ struct ptdump_state {
 			  int level, u64 val);
 	void (*effective_prot)(struct ptdump_state *st, int level, u64 val);
 	const struct ptdump_range *range;
+	bool note_non_leaf;
 };
 
 bool ptdump_walk_pgd_level_core(struct seq_file *m,

diff --git a/mm/ptdump.c b/mm/ptdump.c
index 106e1d66e9f9..97da7a765b22 100644
--- a/mm/ptdump.c
+++ b/mm/ptdump.c

@@ -41,6 +41,9 @@ static int ptdump_pgd_entry(pgd_t *pgd, unsigned long addr,
 	if (st->effective_prot)
 		st->effective_prot(st, 0, pgd_val(val));
 
+	if (st->note_non_leaf && !pgd_leaf(val))
+		st->note_page(st, addr, 0, pgd_val(val));
+
 	if (pgd_leaf(val)) {
 		st->note_page(st, addr, 0, pgd_val(val));
 		walk->action = ACTION_CONTINUE;

@@ -64,6 +67,9 @@ static int ptdump_p4d_entry(p4d_t *p4d, unsigned long addr,
 	if (st->effective_prot)
 		st->effective_prot(st, 1, p4d_val(val));
 
+	if (st->note_non_leaf && !p4d_leaf(val))
+		st->note_page(st, addr, 1, p4d_val(val));
+
 	if (p4d_leaf(val)) {
 		st->note_page(st, addr, 1, p4d_val(val));
 		walk->action = ACTION_CONTINUE;

@@ -87,6 +93,9 @@ static int ptdump_pud_entry(pud_t *pud, unsigned long addr,
 	if (st->effective_prot)
 		st->effective_prot(st, 2, pud_val(val));
 
+	if (st->note_non_leaf && !pud_leaf(val))
+		st->note_page(st, addr, 2, pud_val(val));
+
 	if (pud_leaf(val)) {
 		st->note_page(st, addr, 2, pud_val(val));
 		walk->action = ACTION_CONTINUE;

@@ -108,6 +117,10 @@ static int ptdump_pmd_entry(pmd_t *pmd, unsigned long addr,
 
 	if (st->effective_prot)
 		st->effective_prot(st, 3, pmd_val(val));
+
+	if (st->note_non_leaf && !pmd_leaf(val))
+		st->note_page(st, addr, 3, pmd_val(val));
+
 	if (pmd_leaf(val)) {
 		st->note_page(st, addr, 3, pmd_val(val));
 		walk->action = ACTION_CONTINUE;

-- 
2.39.2

`h`	back out one level
`j`	next message in thread
`k`	previous message in thread
`l`	drill in
`Esc`	close help / fold thread tree
`?`	toggle this help