* [PATCH V2 0/3] mm/ptdump: Drop assumption that pxd_val() is u64
@ 2025-04-07 5:31 Anshuman Khandual
2025-04-07 5:31 ` [PATCH V2 1/3] mm/ptdump: Split note_page() into level specific callbacks Anshuman Khandual
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Anshuman Khandual @ 2025-04-07 5:31 UTC (permalink / raw)
To: linux-mm
Cc: mark.rutland, Anshuman Khandual, Catalin Marinas, Will Deacon,
Steven Price, Ryan Roberts, Madhavan Srinivasan, Nicholas Piggin,
Paul Walmsley, Palmer Dabbelt, Gerald Schaefer, Heiko Carstens,
Peter Zijlstra, Thomas Gleixner, Ingo Molnar, Alexander Gordeev,
Andrew Morton, linux-arm-kernel, linux-kernel, linuxppc-dev,
linux-riscv, linux-s390
Last argument passed down in note_page() is u64 assuming pxd_val() returned
value (all page table levels) is 64 bit - which might not be the case going
ahead when D128 page tables is enabled on arm64 platform. Besides pxd_val()
is very platform specific and its type should not be assumed in generic MM.
A similar problem exists for effective_prot(), although it is restricted to
x86 platform.
This series splits note_page() and effective_prot() into individual page
table level specific callbacks which accepts corresponding pxd_t page table
entry as an argument instead and later on all subscribing platforms could
derive pxd_val() from the table entries as required and proceed as before.
Define ptdesc_t type which describes the basic page table descriptor layout
on arm64 platform. Subsequently all level specific pxxval_t descriptors are
derived from ptdesc_t thus establishing a common original format, which can
also be appropriate for page table entries, masks and protection values etc
which are used at all page table levels.
This series has been tested on arm64 platform but it does build on other
relevant platforms (v6.15-rc1).
Changes in V2:
- Added a patch to split effective_prot() callback per Alexander
- Added a patch to define ptdesc_t data type on arm64 platform per Ryan
Changes in V1:
https://lore.kernel.org/all/20250317061818.16244-1-anshuman.khandual@arm.com/
- Added note_page_flush() callback and implemented the same on all
subscribing platforms
- Moved note_page() argument change from u64 to pteval_t on arm64 platform
from second patch to the first patch instead
Changes in RFC:
https://lore.kernel.org/all/20250310095902.390664-1-anshuman.khandual@arm.com/
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Steven Price <steven.price@arm.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: linux-mm@kvack.org
Anshuman Khandual (3):
mm/ptdump: Split note_page() into level specific callbacks
mm/ptdump: Split effective_prot() into level specific callbacks
arm64/mm: Define ptdesc_t
arch/arm64/include/asm/pgtable-types.h | 20 +++++---
arch/arm64/include/asm/ptdump.h | 24 ++++++---
arch/arm64/kernel/efi.c | 4 +-
arch/arm64/kernel/pi/map_kernel.c | 2 +-
arch/arm64/kernel/pi/map_range.c | 4 +-
arch/arm64/kernel/pi/pi.h | 2 +-
arch/arm64/mm/mmap.c | 2 +-
arch/arm64/mm/ptdump.c | 50 ++++++++++++++++--
arch/powerpc/mm/ptdump/ptdump.c | 46 ++++++++++++++++-
arch/riscv/mm/ptdump.c | 46 ++++++++++++++++-
arch/s390/mm/dump_pagetables.c | 46 ++++++++++++++++-
arch/x86/mm/dump_pagetables.c | 71 +++++++++++++++++++++++++-
include/linux/ptdump.h | 15 ++++--
mm/ptdump.c | 62 ++++++++++++++--------
14 files changed, 339 insertions(+), 55 deletions(-)
--
2.25.1
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH V2 1/3] mm/ptdump: Split note_page() into level specific callbacks
2025-04-07 5:31 [PATCH V2 0/3] mm/ptdump: Drop assumption that pxd_val() is u64 Anshuman Khandual
@ 2025-04-07 5:31 ` Anshuman Khandual
2025-04-07 5:31 ` [PATCH V2 2/3] mm/ptdump: Split effective_prot() " Anshuman Khandual
2025-04-07 5:31 ` [PATCH V2 3/3] arm64/mm: Define ptdesc_t Anshuman Khandual
2 siblings, 0 replies; 4+ messages in thread
From: Anshuman Khandual @ 2025-04-07 5:31 UTC (permalink / raw)
To: linux-mm
Cc: mark.rutland, Anshuman Khandual, Catalin Marinas, Will Deacon,
Steven Price, Ryan Roberts, Madhavan Srinivasan, Nicholas Piggin,
Paul Walmsley, Palmer Dabbelt, Gerald Schaefer, Heiko Carstens,
Peter Zijlstra, Thomas Gleixner, Ingo Molnar, Alexander Gordeev,
Andrew Morton, linux-arm-kernel, linux-kernel, linuxppc-dev,
linux-riscv, linux-s390
Last argument passed down in note_page() is u64 assuming pxd_val() returned
value (all page table levels) is 64 bit - which might not be the case going
ahead when D128 page tables is enabled on arm64 platform. Besides pxd_val()
is very platform specific and its type should not be assumed in generic MM.
Split note_page() into individual page table level specific callbacks which
accepts corresponding pxd_t argument instead and then subscribing platforms
just derive pxd_val() from the entries as required and proceed as earlier.
Also add a note_page_flush() callback for flushing the last page table page
that was being handled earlier via level = -1.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: linux-mm@kvack.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
arch/arm64/include/asm/ptdump.h | 16 +++++++++--
arch/arm64/mm/ptdump.c | 48 ++++++++++++++++++++++++++++++---
arch/powerpc/mm/ptdump/ptdump.c | 46 +++++++++++++++++++++++++++++--
arch/riscv/mm/ptdump.c | 46 +++++++++++++++++++++++++++++--
arch/s390/mm/dump_pagetables.c | 46 +++++++++++++++++++++++++++++--
arch/x86/mm/dump_pagetables.c | 39 ++++++++++++++++++++++++++-
include/linux/ptdump.h | 9 ++++---
mm/ptdump.c | 42 ++++++++++++++++++++++-------
8 files changed, 267 insertions(+), 25 deletions(-)
diff --git a/arch/arm64/include/asm/ptdump.h b/arch/arm64/include/asm/ptdump.h
index b2931d1ae0fb..01033c1d38dc 100644
--- a/arch/arm64/include/asm/ptdump.h
+++ b/arch/arm64/include/asm/ptdump.h
@@ -59,7 +59,13 @@ struct ptdump_pg_state {
void ptdump_walk(struct seq_file *s, struct ptdump_info *info);
void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
- u64 val);
+ pteval_t val);
+void note_page_pte(struct ptdump_state *st, unsigned long addr, pte_t pte);
+void note_page_pmd(struct ptdump_state *st, unsigned long addr, pmd_t pmd);
+void note_page_pud(struct ptdump_state *st, unsigned long addr, pud_t pud);
+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);
#ifdef CONFIG_PTDUMP_DEBUGFS
#define EFI_RUNTIME_MAP_END DEFAULT_MAP_WINDOW_64
void __init ptdump_debugfs_register(struct ptdump_info *info, const char *name);
@@ -69,7 +75,13 @@ static inline void ptdump_debugfs_register(struct ptdump_info *info,
#endif /* CONFIG_PTDUMP_DEBUGFS */
#else
static inline void note_page(struct ptdump_state *pt_st, unsigned long addr,
- int level, u64 val) { }
+ int level, pteval_t val) { }
+static inline void note_page_pte(struct ptdump_state *st, unsigned long addr, pte_t pte) { }
+static inline void note_page_pmd(struct ptdump_state *st, unsigned long addr, pmd_t pmd) { }
+static inline void note_page_pud(struct ptdump_state *st, unsigned long addr, pud_t pud) { }
+static inline void note_page_p4d(struct ptdump_state *st, unsigned long addr, p4d_t p4d) { }
+static inline void note_page_pgd(struct ptdump_state *st, unsigned long addr, pgd_t pgd) { }
+static inline void note_page_flush(struct ptdump_state *st) { }
#endif /* CONFIG_PTDUMP */
#endif /* __ASM_PTDUMP_H */
diff --git a/arch/arm64/mm/ptdump.c b/arch/arm64/mm/ptdump.c
index 8cec0da4cff2..ac0c20ba0cd9 100644
--- a/arch/arm64/mm/ptdump.c
+++ b/arch/arm64/mm/ptdump.c
@@ -189,7 +189,7 @@ static void note_prot_wx(struct ptdump_pg_state *st, unsigned long addr)
}
void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
- u64 val)
+ pteval_t val)
{
struct ptdump_pg_state *st = container_of(pt_st, struct ptdump_pg_state, ptdump);
struct ptdump_pg_level *pg_level = st->pg_level;
@@ -251,6 +251,38 @@ void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
}
+void note_page_pte(struct ptdump_state *pt_st, unsigned long addr, pte_t pte)
+{
+ note_page(pt_st, addr, 4, pte_val(pte));
+}
+
+void note_page_pmd(struct ptdump_state *pt_st, unsigned long addr, pmd_t pmd)
+{
+ note_page(pt_st, addr, 3, pmd_val(pmd));
+}
+
+void note_page_pud(struct ptdump_state *pt_st, unsigned long addr, pud_t pud)
+{
+ note_page(pt_st, addr, 2, pud_val(pud));
+}
+
+void note_page_p4d(struct ptdump_state *pt_st, unsigned long addr, p4d_t p4d)
+{
+ note_page(pt_st, addr, 1, p4d_val(p4d));
+}
+
+void note_page_pgd(struct ptdump_state *pt_st, unsigned long addr, pgd_t pgd)
+{
+ note_page(pt_st, addr, 0, pgd_val(pgd));
+}
+
+void note_page_flush(struct ptdump_state *pt_st)
+{
+ pte_t pte_zero = {0};
+
+ note_page(pt_st, 0, -1, pte_val(pte_zero));
+}
+
void ptdump_walk(struct seq_file *s, struct ptdump_info *info)
{
unsigned long end = ~0UL;
@@ -266,7 +298,12 @@ void ptdump_walk(struct seq_file *s, struct ptdump_info *info)
.pg_level = &kernel_pg_levels[0],
.level = -1,
.ptdump = {
- .note_page = note_page,
+ .note_page_pte = note_page_pte,
+ .note_page_pmd = note_page_pmd,
+ .note_page_pud = note_page_pud,
+ .note_page_p4d = note_page_p4d,
+ .note_page_pgd = note_page_pgd,
+ .note_page_flush = note_page_flush,
.range = (struct ptdump_range[]){
{info->base_addr, end},
{0, 0}
@@ -303,7 +340,12 @@ bool ptdump_check_wx(void)
.level = -1,
.check_wx = true,
.ptdump = {
- .note_page = note_page,
+ .note_page_pte = note_page_pte,
+ .note_page_pmd = note_page_pmd,
+ .note_page_pud = note_page_pud,
+ .note_page_p4d = note_page_p4d,
+ .note_page_pgd = note_page_pgd,
+ .note_page_flush = note_page_flush,
.range = (struct ptdump_range[]) {
{_PAGE_OFFSET(vabits_actual), ~0UL},
{0, 0}
diff --git a/arch/powerpc/mm/ptdump/ptdump.c b/arch/powerpc/mm/ptdump/ptdump.c
index 9dc239967b77..b2358d794855 100644
--- a/arch/powerpc/mm/ptdump/ptdump.c
+++ b/arch/powerpc/mm/ptdump/ptdump.c
@@ -298,6 +298,38 @@ static void populate_markers(void)
#endif
}
+static void note_page_pte(struct ptdump_state *pt_st, unsigned long addr, pte_t pte)
+{
+ note_page(pt_st, addr, 4, pte_val(pte));
+}
+
+static void note_page_pmd(struct ptdump_state *pt_st, unsigned long addr, pmd_t pmd)
+{
+ note_page(pt_st, addr, 3, pmd_val(pmd));
+}
+
+static void note_page_pud(struct ptdump_state *pt_st, unsigned long addr, pud_t pud)
+{
+ note_page(pt_st, addr, 2, pud_val(pud));
+}
+
+static void note_page_p4d(struct ptdump_state *pt_st, unsigned long addr, p4d_t p4d)
+{
+ note_page(pt_st, addr, 1, p4d_val(p4d));
+}
+
+static void note_page_pgd(struct ptdump_state *pt_st, unsigned long addr, pgd_t pgd)
+{
+ note_page(pt_st, addr, 0, pgd_val(pgd));
+}
+
+static void note_page_flush(struct ptdump_state *pt_st)
+{
+ pte_t pte_zero = {0};
+
+ note_page(pt_st, 0, -1, pte_val(pte_zero));
+}
+
static int ptdump_show(struct seq_file *m, void *v)
{
struct pg_state st = {
@@ -305,7 +337,12 @@ static int ptdump_show(struct seq_file *m, void *v)
.marker = address_markers,
.level = -1,
.ptdump = {
- .note_page = note_page,
+ .note_page_pte = note_page_pte,
+ .note_page_pmd = note_page_pmd,
+ .note_page_pud = note_page_pud,
+ .note_page_p4d = note_page_p4d,
+ .note_page_pgd = note_page_pgd,
+ .note_page_flush = note_page_flush,
.range = ptdump_range,
}
};
@@ -338,7 +375,12 @@ bool ptdump_check_wx(void)
.level = -1,
.check_wx = true,
.ptdump = {
- .note_page = note_page,
+ .note_page_pte = note_page_pte,
+ .note_page_pmd = note_page_pmd,
+ .note_page_pud = note_page_pud,
+ .note_page_p4d = note_page_p4d,
+ .note_page_pgd = note_page_pgd,
+ .note_page_flush = note_page_flush,
.range = ptdump_range,
}
};
diff --git a/arch/riscv/mm/ptdump.c b/arch/riscv/mm/ptdump.c
index 9d5f657a251b..32922550a50a 100644
--- a/arch/riscv/mm/ptdump.c
+++ b/arch/riscv/mm/ptdump.c
@@ -318,6 +318,38 @@ static void note_page(struct ptdump_state *pt_st, unsigned long addr,
}
}
+static void note_page_pte(struct ptdump_state *pt_st, unsigned long addr, pte_t pte)
+{
+ note_page(pt_st, addr, 4, pte_val(pte));
+}
+
+static void note_page_pmd(struct ptdump_state *pt_st, unsigned long addr, pmd_t pmd)
+{
+ note_page(pt_st, addr, 3, pmd_val(pmd));
+}
+
+static void note_page_pud(struct ptdump_state *pt_st, unsigned long addr, pud_t pud)
+{
+ note_page(pt_st, addr, 2, pud_val(pud));
+}
+
+static void note_page_p4d(struct ptdump_state *pt_st, unsigned long addr, p4d_t p4d)
+{
+ note_page(pt_st, addr, 1, p4d_val(p4d));
+}
+
+static void note_page_pgd(struct ptdump_state *pt_st, unsigned long addr, pgd_t pgd)
+{
+ note_page(pt_st, addr, 0, pgd_val(pgd));
+}
+
+static void note_page_flush(struct ptdump_state *pt_st)
+{
+ pte_t pte_zero = {0};
+
+ note_page(pt_st, 0, -1, pte_val(pte_zero));
+}
+
static void ptdump_walk(struct seq_file *s, struct ptd_mm_info *pinfo)
{
struct pg_state st = {
@@ -325,7 +357,12 @@ static void ptdump_walk(struct seq_file *s, struct ptd_mm_info *pinfo)
.marker = pinfo->markers,
.level = -1,
.ptdump = {
- .note_page = note_page,
+ .note_page_pte = note_page_pte,
+ .note_page_pmd = note_page_pmd,
+ .note_page_pud = note_page_pud,
+ .note_page_p4d = note_page_p4d,
+ .note_page_pgd = note_page_pgd,
+ .note_page_flush = note_page_flush,
.range = (struct ptdump_range[]) {
{pinfo->base_addr, pinfo->end},
{0, 0}
@@ -347,7 +384,12 @@ bool ptdump_check_wx(void)
.level = -1,
.check_wx = true,
.ptdump = {
- .note_page = note_page,
+ .note_page_pte = note_page_pte,
+ .note_page_pmd = note_page_pmd,
+ .note_page_pud = note_page_pud,
+ .note_page_p4d = note_page_p4d,
+ .note_page_pgd = note_page_pgd,
+ .note_page_flush = note_page_flush,
.range = (struct ptdump_range[]) {
{KERN_VIRT_START, ULONG_MAX},
{0, 0}
diff --git a/arch/s390/mm/dump_pagetables.c b/arch/s390/mm/dump_pagetables.c
index d3e943752fa0..ac604b176660 100644
--- a/arch/s390/mm/dump_pagetables.c
+++ b/arch/s390/mm/dump_pagetables.c
@@ -147,11 +147,48 @@ static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
}
}
+static void note_page_pte(struct ptdump_state *pt_st, unsigned long addr, pte_t pte)
+{
+ note_page(pt_st, addr, 4, pte_val(pte));
+}
+
+static void note_page_pmd(struct ptdump_state *pt_st, unsigned long addr, pmd_t pmd)
+{
+ note_page(pt_st, addr, 3, pmd_val(pmd));
+}
+
+static void note_page_pud(struct ptdump_state *pt_st, unsigned long addr, pud_t pud)
+{
+ note_page(pt_st, addr, 2, pud_val(pud));
+}
+
+static void note_page_p4d(struct ptdump_state *pt_st, unsigned long addr, p4d_t p4d)
+{
+ note_page(pt_st, addr, 1, p4d_val(p4d));
+}
+
+static void note_page_pgd(struct ptdump_state *pt_st, unsigned long addr, pgd_t pgd)
+{
+ note_page(pt_st, addr, 0, pgd_val(pgd));
+}
+
+static void note_page_flush(struct ptdump_state *pt_st)
+{
+ pte_t pte_zero = {0};
+
+ note_page(pt_st, 0, -1, pte_val(pte_zero));
+}
+
bool ptdump_check_wx(void)
{
struct pg_state st = {
.ptdump = {
- .note_page = note_page,
+ .note_page_pte = note_page_pte,
+ .note_page_pmd = note_page_pmd,
+ .note_page_pud = note_page_pud,
+ .note_page_p4d = note_page_p4d,
+ .note_page_pgd = note_page_pgd,
+ .note_page_flush = note_page_flush,
.range = (struct ptdump_range[]) {
{.start = 0, .end = max_addr},
{.start = 0, .end = 0},
@@ -190,7 +227,12 @@ static int ptdump_show(struct seq_file *m, void *v)
{
struct pg_state st = {
.ptdump = {
- .note_page = note_page,
+ .note_page_pte = note_page_pte,
+ .note_page_pmd = note_page_pmd,
+ .note_page_pud = note_page_pud,
+ .note_page_p4d = note_page_p4d,
+ .note_page_pgd = note_page_pgd,
+ .note_page_flush = note_page_flush,
.range = (struct ptdump_range[]) {
{.start = 0, .end = max_addr},
{.start = 0, .end = 0},
diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
index 89079ea73e65..2e1c2d006ace 100644
--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c
@@ -362,6 +362,38 @@ static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
}
}
+static void note_page_pte(struct ptdump_state *pt_st, unsigned long addr, pte_t pte)
+{
+ note_page(pt_st, addr, 4, pte_val(pte));
+}
+
+static void note_page_pmd(struct ptdump_state *pt_st, unsigned long addr, pmd_t pmd)
+{
+ note_page(pt_st, addr, 3, pmd_val(pmd));
+}
+
+static void note_page_pud(struct ptdump_state *pt_st, unsigned long addr, pud_t pud)
+{
+ note_page(pt_st, addr, 2, pud_val(pud));
+}
+
+static void note_page_p4d(struct ptdump_state *pt_st, unsigned long addr, p4d_t p4d)
+{
+ note_page(pt_st, addr, 1, p4d_val(p4d));
+}
+
+static void note_page_pgd(struct ptdump_state *pt_st, unsigned long addr, pgd_t pgd)
+{
+ note_page(pt_st, addr, 0, pgd_val(pgd));
+}
+
+static void note_page_flush(struct ptdump_state *pt_st)
+{
+ pte_t pte_zero = {0};
+
+ note_page(pt_st, 0, -1, pte_val(pte_zero));
+}
+
bool ptdump_walk_pgd_level_core(struct seq_file *m,
struct mm_struct *mm, pgd_t *pgd,
bool checkwx, bool dmesg)
@@ -378,7 +410,12 @@ bool ptdump_walk_pgd_level_core(struct seq_file *m,
struct pg_state st = {
.ptdump = {
- .note_page = note_page,
+ .note_page_pte = note_page_pte,
+ .note_page_pmd = note_page_pmd,
+ .note_page_pud = note_page_pud,
+ .note_page_p4d = note_page_p4d,
+ .note_page_pgd = note_page_pgd,
+ .note_page_flush = note_page_flush,
.effective_prot = effective_prot,
.range = ptdump_ranges
},
diff --git a/include/linux/ptdump.h b/include/linux/ptdump.h
index 8dbd51ea8626..1c1eb1fae199 100644
--- a/include/linux/ptdump.h
+++ b/include/linux/ptdump.h
@@ -11,9 +11,12 @@ struct ptdump_range {
};
struct ptdump_state {
- /* level is 0:PGD to 4:PTE, or -1 if unknown */
- void (*note_page)(struct ptdump_state *st, unsigned long addr,
- int level, u64 val);
+ void (*note_page_pte)(struct ptdump_state *st, unsigned long addr, pte_t pte);
+ void (*note_page_pmd)(struct ptdump_state *st, unsigned long addr, pmd_t pmd);
+ void (*note_page_pud)(struct ptdump_state *st, unsigned long addr, pud_t pud);
+ 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);
const struct ptdump_range *range;
};
diff --git a/mm/ptdump.c b/mm/ptdump.c
index 106e1d66e9f9..706cfc19439b 100644
--- a/mm/ptdump.c
+++ b/mm/ptdump.c
@@ -18,7 +18,7 @@ static inline int note_kasan_page_table(struct mm_walk *walk,
{
struct ptdump_state *st = walk->private;
- st->note_page(st, addr, 4, pte_val(kasan_early_shadow_pte[0]));
+ st->note_page_pte(st, addr, kasan_early_shadow_pte[0]);
walk->action = ACTION_CONTINUE;
@@ -42,7 +42,7 @@ static int ptdump_pgd_entry(pgd_t *pgd, unsigned long addr,
st->effective_prot(st, 0, pgd_val(val));
if (pgd_leaf(val)) {
- st->note_page(st, addr, 0, pgd_val(val));
+ st->note_page_pgd(st, addr, val);
walk->action = ACTION_CONTINUE;
}
@@ -65,7 +65,7 @@ static int ptdump_p4d_entry(p4d_t *p4d, unsigned long addr,
st->effective_prot(st, 1, p4d_val(val));
if (p4d_leaf(val)) {
- st->note_page(st, addr, 1, p4d_val(val));
+ st->note_page_p4d(st, addr, val);
walk->action = ACTION_CONTINUE;
}
@@ -88,7 +88,7 @@ static int ptdump_pud_entry(pud_t *pud, unsigned long addr,
st->effective_prot(st, 2, pud_val(val));
if (pud_leaf(val)) {
- st->note_page(st, addr, 2, pud_val(val));
+ st->note_page_pud(st, addr, val);
walk->action = ACTION_CONTINUE;
}
@@ -109,7 +109,7 @@ 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)) {
- st->note_page(st, addr, 3, pmd_val(val));
+ st->note_page_pmd(st, addr, val);
walk->action = ACTION_CONTINUE;
}
@@ -125,7 +125,7 @@ static int ptdump_pte_entry(pte_t *pte, unsigned long addr,
if (st->effective_prot)
st->effective_prot(st, 4, pte_val(val));
- st->note_page(st, addr, 4, pte_val(val));
+ st->note_page_pte(st, addr, val);
return 0;
}
@@ -134,9 +134,31 @@ static int ptdump_hole(unsigned long addr, unsigned long next,
int depth, struct mm_walk *walk)
{
struct ptdump_state *st = walk->private;
-
- st->note_page(st, addr, depth, 0);
-
+ pte_t pte_zero = {0};
+ pmd_t pmd_zero = {0};
+ pud_t pud_zero = {0};
+ p4d_t p4d_zero = {0};
+ pgd_t pgd_zero = {0};
+
+ switch (depth) {
+ case 4:
+ st->note_page_pte(st, addr, pte_zero);
+ break;
+ case 3:
+ st->note_page_pmd(st, addr, pmd_zero);
+ break;
+ case 2:
+ st->note_page_pud(st, addr, pud_zero);
+ break;
+ case 1:
+ st->note_page_p4d(st, addr, p4d_zero);
+ break;
+ case 0:
+ st->note_page_pgd(st, addr, pgd_zero);
+ break;
+ default:
+ break;
+ }
return 0;
}
@@ -162,7 +184,7 @@ void ptdump_walk_pgd(struct ptdump_state *st, struct mm_struct *mm, pgd_t *pgd)
mmap_write_unlock(mm);
/* Flush out the last page */
- st->note_page(st, 0, -1, 0);
+ st->note_page_flush(st);
}
static int check_wx_show(struct seq_file *m, void *v)
--
2.25.1
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH V2 2/3] mm/ptdump: Split effective_prot() into level specific callbacks
2025-04-07 5:31 [PATCH V2 0/3] mm/ptdump: Drop assumption that pxd_val() is u64 Anshuman Khandual
2025-04-07 5:31 ` [PATCH V2 1/3] mm/ptdump: Split note_page() into level specific callbacks Anshuman Khandual
@ 2025-04-07 5:31 ` Anshuman Khandual
2025-04-07 5:31 ` [PATCH V2 3/3] arm64/mm: Define ptdesc_t Anshuman Khandual
2 siblings, 0 replies; 4+ messages in thread
From: Anshuman Khandual @ 2025-04-07 5:31 UTC (permalink / raw)
To: linux-mm
Cc: mark.rutland, Anshuman Khandual, Catalin Marinas, Will Deacon,
Steven Price, Ryan Roberts, Madhavan Srinivasan, Nicholas Piggin,
Paul Walmsley, Palmer Dabbelt, Gerald Schaefer, Heiko Carstens,
Peter Zijlstra, Thomas Gleixner, Ingo Molnar, Alexander Gordeev,
Andrew Morton, linux-arm-kernel, linux-kernel, linuxppc-dev,
linux-riscv, linux-s390, Dave Hansen
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 <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
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 <anshuman.khandual@arm.com>
---
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
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH V2 3/3] arm64/mm: Define ptdesc_t
2025-04-07 5:31 [PATCH V2 0/3] mm/ptdump: Drop assumption that pxd_val() is u64 Anshuman Khandual
2025-04-07 5:31 ` [PATCH V2 1/3] mm/ptdump: Split note_page() into level specific callbacks Anshuman Khandual
2025-04-07 5:31 ` [PATCH V2 2/3] mm/ptdump: Split effective_prot() " Anshuman Khandual
@ 2025-04-07 5:31 ` Anshuman Khandual
2 siblings, 0 replies; 4+ messages in thread
From: Anshuman Khandual @ 2025-04-07 5:31 UTC (permalink / raw)
To: linux-mm
Cc: mark.rutland, Anshuman Khandual, Catalin Marinas, Will Deacon,
Steven Price, Ryan Roberts, Madhavan Srinivasan, Nicholas Piggin,
Paul Walmsley, Palmer Dabbelt, Gerald Schaefer, Heiko Carstens,
Peter Zijlstra, Thomas Gleixner, Ingo Molnar, Alexander Gordeev,
Andrew Morton, linux-arm-kernel, linux-kernel, linuxppc-dev,
linux-riscv, linux-s390, Ard Biesheuvel, linux-efi
Define ptdesc_t type which describes the basic page table descriptor layout
on arm64 platform. Subsequently all level specific pxxval_t descriptors are
derived from ptdesc_t thus establishing a common original format, which can
also be appropriate for page table entries, masks and protection values etc
which are used at all page table levels.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Suggested-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
arch/arm64/include/asm/pgtable-types.h | 20 ++++++++++++++------
arch/arm64/include/asm/ptdump.h | 8 ++++----
arch/arm64/kernel/efi.c | 4 ++--
arch/arm64/kernel/pi/map_kernel.c | 2 +-
arch/arm64/kernel/pi/map_range.c | 4 ++--
arch/arm64/kernel/pi/pi.h | 2 +-
arch/arm64/mm/mmap.c | 2 +-
arch/arm64/mm/ptdump.c | 2 +-
8 files changed, 26 insertions(+), 18 deletions(-)
diff --git a/arch/arm64/include/asm/pgtable-types.h b/arch/arm64/include/asm/pgtable-types.h
index 6d6d4065b0cb..265e8301d7ba 100644
--- a/arch/arm64/include/asm/pgtable-types.h
+++ b/arch/arm64/include/asm/pgtable-types.h
@@ -11,11 +11,19 @@
#include <asm/types.h>
-typedef u64 pteval_t;
-typedef u64 pmdval_t;
-typedef u64 pudval_t;
-typedef u64 p4dval_t;
-typedef u64 pgdval_t;
+/*
+ * Page Table Descriptor
+ *
+ * Generic page table descriptor format from which
+ * all level specific descriptors can be derived.
+ */
+typedef u64 ptdesc_t;
+
+typedef ptdesc_t pteval_t;
+typedef ptdesc_t pmdval_t;
+typedef ptdesc_t pudval_t;
+typedef ptdesc_t p4dval_t;
+typedef ptdesc_t pgdval_t;
/*
* These are used to make use of C type-checking..
@@ -46,7 +54,7 @@ typedef struct { pgdval_t pgd; } pgd_t;
#define pgd_val(x) ((x).pgd)
#define __pgd(x) ((pgd_t) { (x) } )
-typedef struct { pteval_t pgprot; } pgprot_t;
+typedef struct { ptdesc_t pgprot; } pgprot_t;
#define pgprot_val(x) ((x).pgprot)
#define __pgprot(x) ((pgprot_t) { (x) } )
diff --git a/arch/arm64/include/asm/ptdump.h b/arch/arm64/include/asm/ptdump.h
index 01033c1d38dc..fded5358641f 100644
--- a/arch/arm64/include/asm/ptdump.h
+++ b/arch/arm64/include/asm/ptdump.h
@@ -24,8 +24,8 @@ struct ptdump_info {
};
struct ptdump_prot_bits {
- u64 mask;
- u64 val;
+ ptdesc_t mask;
+ ptdesc_t val;
const char *set;
const char *clear;
};
@@ -34,7 +34,7 @@ struct ptdump_pg_level {
const struct ptdump_prot_bits *bits;
char name[4];
int num;
- u64 mask;
+ ptdesc_t mask;
};
/*
@@ -51,7 +51,7 @@ struct ptdump_pg_state {
const struct mm_struct *mm;
unsigned long start_address;
int level;
- u64 current_prot;
+ ptdesc_t current_prot;
bool check_wx;
unsigned long wx_pages;
unsigned long uxn_pages;
diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c
index 1d25d8899dbf..42e281c07c2f 100644
--- a/arch/arm64/kernel/efi.c
+++ b/arch/arm64/kernel/efi.c
@@ -29,7 +29,7 @@ static bool region_is_misaligned(const efi_memory_desc_t *md)
* executable, everything else can be mapped with the XN bits
* set. Also take the new (optional) RO/XP bits into account.
*/
-static __init pteval_t create_mapping_protection(efi_memory_desc_t *md)
+static __init ptdesc_t create_mapping_protection(efi_memory_desc_t *md)
{
u64 attr = md->attribute;
u32 type = md->type;
@@ -83,7 +83,7 @@ static __init pteval_t create_mapping_protection(efi_memory_desc_t *md)
int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md)
{
- pteval_t prot_val = create_mapping_protection(md);
+ ptdesc_t prot_val = create_mapping_protection(md);
bool page_mappings_only = (md->type == EFI_RUNTIME_SERVICES_CODE ||
md->type == EFI_RUNTIME_SERVICES_DATA);
diff --git a/arch/arm64/kernel/pi/map_kernel.c b/arch/arm64/kernel/pi/map_kernel.c
index e57b043f324b..a00f57c73d81 100644
--- a/arch/arm64/kernel/pi/map_kernel.c
+++ b/arch/arm64/kernel/pi/map_kernel.c
@@ -159,7 +159,7 @@ static void noinline __section(".idmap.text") set_ttbr0_for_lpa2(u64 ttbr)
static void __init remap_idmap_for_lpa2(void)
{
/* clear the bits that change meaning once LPA2 is turned on */
- pteval_t mask = PTE_SHARED;
+ ptdesc_t mask = PTE_SHARED;
/*
* We have to clear bits [9:8] in all block or page descriptors in the
diff --git a/arch/arm64/kernel/pi/map_range.c b/arch/arm64/kernel/pi/map_range.c
index 81345f68f9fc..7982788e7b9a 100644
--- a/arch/arm64/kernel/pi/map_range.c
+++ b/arch/arm64/kernel/pi/map_range.c
@@ -30,7 +30,7 @@ void __init map_range(u64 *pte, u64 start, u64 end, u64 pa, pgprot_t prot,
int level, pte_t *tbl, bool may_use_cont, u64 va_offset)
{
u64 cmask = (level == 3) ? CONT_PTE_SIZE - 1 : U64_MAX;
- pteval_t protval = pgprot_val(prot) & ~PTE_TYPE_MASK;
+ ptdesc_t protval = pgprot_val(prot) & ~PTE_TYPE_MASK;
int lshift = (3 - level) * PTDESC_TABLE_SHIFT;
u64 lmask = (PAGE_SIZE << lshift) - 1;
@@ -87,7 +87,7 @@ void __init map_range(u64 *pte, u64 start, u64 end, u64 pa, pgprot_t prot,
}
}
-asmlinkage u64 __init create_init_idmap(pgd_t *pg_dir, pteval_t clrmask)
+asmlinkage u64 __init create_init_idmap(pgd_t *pg_dir, ptdesc_t clrmask)
{
u64 ptep = (u64)pg_dir + PAGE_SIZE;
pgprot_t text_prot = PAGE_KERNEL_ROX;
diff --git a/arch/arm64/kernel/pi/pi.h b/arch/arm64/kernel/pi/pi.h
index c91e5e965cd3..91dcb5b6bbd1 100644
--- a/arch/arm64/kernel/pi/pi.h
+++ b/arch/arm64/kernel/pi/pi.h
@@ -33,4 +33,4 @@ void map_range(u64 *pgd, u64 start, u64 end, u64 pa, pgprot_t prot,
asmlinkage void early_map_kernel(u64 boot_status, void *fdt);
-asmlinkage u64 create_init_idmap(pgd_t *pgd, pteval_t clrmask);
+asmlinkage u64 create_init_idmap(pgd_t *pgd, ptdesc_t clrmask);
diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c
index 07aeab8a7606..c86c348857c4 100644
--- a/arch/arm64/mm/mmap.c
+++ b/arch/arm64/mm/mmap.c
@@ -83,7 +83,7 @@ arch_initcall(adjust_protection_map);
pgprot_t vm_get_page_prot(unsigned long vm_flags)
{
- pteval_t prot;
+ ptdesc_t prot;
/* Short circuit GCS to avoid bloating the table. */
if (system_supports_gcs() && (vm_flags & VM_SHADOW_STACK)) {
diff --git a/arch/arm64/mm/ptdump.c b/arch/arm64/mm/ptdump.c
index ac0c20ba0cd9..421a5de806c6 100644
--- a/arch/arm64/mm/ptdump.c
+++ b/arch/arm64/mm/ptdump.c
@@ -194,7 +194,7 @@ void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
struct ptdump_pg_state *st = container_of(pt_st, struct ptdump_pg_state, ptdump);
struct ptdump_pg_level *pg_level = st->pg_level;
static const char units[] = "KMGTPE";
- u64 prot = 0;
+ ptdesc_t prot = 0;
/* check if the current level has been folded dynamically */
if (st->mm && ((level == 1 && mm_p4d_folded(st->mm)) ||
--
2.25.1
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2025-04-07 5:31 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2025-04-07 5:31 [PATCH V2 0/3] mm/ptdump: Drop assumption that pxd_val() is u64 Anshuman Khandual
2025-04-07 5:31 ` [PATCH V2 1/3] mm/ptdump: Split note_page() into level specific callbacks Anshuman Khandual
2025-04-07 5:31 ` [PATCH V2 2/3] mm/ptdump: Split effective_prot() " Anshuman Khandual
2025-04-07 5:31 ` [PATCH V2 3/3] arm64/mm: Define ptdesc_t Anshuman Khandual
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox