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[PATCH v10 2/5] arm64: ptdump: Expose the attribute parsing functionality

Sebastian Ene posted 5 patches 2 months, 3 weeks ago
[PATCH v10 2/5] arm64: ptdump: Expose the attribute parsing functionality
Posted by Sebastian Ene 2 months, 3 weeks ago 
Reuse the descriptor parsing functionality to keep the same output format
as the original ptdump code. In order for this to happen, move the state
tracking objects into a common header.

Signed-off-by: Sebastian Ene <sebastianene@google.com>
---
 arch/arm64/include/asm/ptdump.h | 41 +++++++++++++++++++++++-
 arch/arm64/mm/ptdump.c          | 55 +++++++--------------------------
 2 files changed, 51 insertions(+), 45 deletions(-)

diff --git a/arch/arm64/include/asm/ptdump.h b/arch/arm64/include/asm/ptdump.h
index 5b1701c76d1c..bd5d3ee3e8dc 100644
--- a/arch/arm64/include/asm/ptdump.h
+++ b/arch/arm64/include/asm/ptdump.h
@@ -9,6 +9,7 @@
 
 #include <linux/mm_types.h>
 #include <linux/seq_file.h>
+#include <linux/ptdump.h>
 
 struct addr_marker {
 	unsigned long start_address;
@@ -21,14 +22,52 @@ struct ptdump_info {
 	unsigned long			base_addr;
 };
 
+struct ptdump_prot_bits {
+	u64		mask;
+	u64		val;
+	const char	*set;
+	const char	*clear;
+};
+
+struct ptdump_pg_level {
+	const struct ptdump_prot_bits *bits;
+	char name[4];
+	int num;
+	u64 mask;
+};
+
+/*
+ * The page dumper groups page table entries of the same type into a single
+ * description. It uses pg_state to track the range information while
+ * iterating over the pte entries. When the continuity is broken it then
+ * dumps out a description of the range.
+ */
+struct ptdump_pg_state {
+	struct ptdump_state ptdump;
+	struct seq_file *seq;
+	const struct addr_marker *marker;
+	const struct mm_struct *mm;
+	unsigned long start_address;
+	int level;
+	u64 current_prot;
+	bool check_wx;
+	unsigned long wx_pages;
+	unsigned long uxn_pages;
+};
+
 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);
 #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);
 #else
 static inline void ptdump_debugfs_register(struct ptdump_info *info,
 					   const char *name) { }
-#endif
+#endif /* CONFIG_PTDUMP_DEBUGFS */
+#else
+static inline void note_page(void *pt_st, unsigned long addr,
+			     int level, u64 val) { }
 #endif /* CONFIG_PTDUMP_CORE */
 
 #endif /* __ASM_PTDUMP_H */
diff --git a/arch/arm64/mm/ptdump.c b/arch/arm64/mm/ptdump.c
index 6986827e0d64..404751fd30fe 100644
--- a/arch/arm64/mm/ptdump.c
+++ b/arch/arm64/mm/ptdump.c
@@ -38,33 +38,7 @@
 		seq_printf(m, fmt);	\
 })
 
-/*
- * The page dumper groups page table entries of the same type into a single
- * description. It uses pg_state to track the range information while
- * iterating over the pte entries. When the continuity is broken it then
- * dumps out a description of the range.
- */
-struct pg_state {
-	struct ptdump_state ptdump;
-	struct seq_file *seq;
-	const struct addr_marker *marker;
-	const struct mm_struct *mm;
-	unsigned long start_address;
-	int level;
-	u64 current_prot;
-	bool check_wx;
-	unsigned long wx_pages;
-	unsigned long uxn_pages;
-};
-
-struct prot_bits {
-	u64		mask;
-	u64		val;
-	const char	*set;
-	const char	*clear;
-};
-
-static const struct prot_bits pte_bits[] = {
+static const struct ptdump_prot_bits pte_bits[] = {
 	{
 		.mask	= PTE_VALID,
 		.val	= PTE_VALID,
@@ -143,14 +117,7 @@ static const struct prot_bits pte_bits[] = {
 	}
 };
 
-struct pg_level {
-	const struct prot_bits *bits;
-	char name[4];
-	int num;
-	u64 mask;
-};
-
-static struct pg_level pg_level[] __ro_after_init = {
+static struct ptdump_pg_level pg_level[] __ro_after_init = {
 	{ /* pgd */
 		.name	= "PGD",
 		.bits	= pte_bits,
@@ -174,7 +141,7 @@ static struct pg_level pg_level[] __ro_after_init = {
 	},
 };
 
-static void dump_prot(struct pg_state *st, const struct prot_bits *bits,
+static void dump_prot(struct ptdump_pg_state *st, const struct ptdump_prot_bits *bits,
 			size_t num)
 {
 	unsigned i;
@@ -192,7 +159,7 @@ static void dump_prot(struct pg_state *st, const struct prot_bits *bits,
 	}
 }
 
-static void note_prot_uxn(struct pg_state *st, unsigned long addr)
+static void note_prot_uxn(struct ptdump_pg_state *st, unsigned long addr)
 {
 	if (!st->check_wx)
 		return;
@@ -206,7 +173,7 @@ static void note_prot_uxn(struct pg_state *st, unsigned long addr)
 	st->uxn_pages += (addr - st->start_address) / PAGE_SIZE;
 }
 
-static void note_prot_wx(struct pg_state *st, unsigned long addr)
+static void note_prot_wx(struct ptdump_pg_state *st, unsigned long addr)
 {
 	if (!st->check_wx)
 		return;
@@ -221,10 +188,10 @@ static void note_prot_wx(struct pg_state *st, unsigned long addr)
 	st->wx_pages += (addr - st->start_address) / PAGE_SIZE;
 }
 
-static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
-		      u64 val)
+void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
+	       u64 val)
 {
-	struct pg_state *st = container_of(pt_st, struct pg_state, ptdump);
+	struct ptdump_pg_state *st = container_of(pt_st, struct ptdump_pg_state, ptdump);
 	static const char units[] = "KMGTPE";
 	u64 prot = 0;
 
@@ -286,12 +253,12 @@ static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
 void ptdump_walk(struct seq_file *s, struct ptdump_info *info)
 {
 	unsigned long end = ~0UL;
-	struct pg_state st;
+	struct ptdump_pg_state st;
 
 	if (info->base_addr < TASK_SIZE_64)
 		end = TASK_SIZE_64;
 
-	st = (struct pg_state){
+	st = (struct ptdump_pg_state){
 		.seq = s,
 		.marker = info->markers,
 		.mm = info->mm,
@@ -324,7 +291,7 @@ static struct ptdump_info kernel_ptdump_info __ro_after_init = {
 
 bool ptdump_check_wx(void)
 {
-	struct pg_state st = {
+	struct ptdump_pg_state st = {
 		.seq = NULL,
 		.marker = (struct addr_marker[]) {
 			{ 0, NULL},
-- 
2.46.0.469.g59c65b2a67-goog
Re: [PATCH v10 2/5] arm64: ptdump: Expose the attribute parsing functionality
Posted by Will Deacon 2 months, 3 weeks ago 
On Mon, Sep 09, 2024 at 12:47:18PM +0000, Sebastian Ene wrote:
> Reuse the descriptor parsing functionality to keep the same output format
> as the original ptdump code. In order for this to happen, move the state
> tracking objects into a common header.
> 
> Signed-off-by: Sebastian Ene <sebastianene@google.com>
> ---
>  arch/arm64/include/asm/ptdump.h | 41 +++++++++++++++++++++++-
>  arch/arm64/mm/ptdump.c          | 55 +++++++--------------------------
>  2 files changed, 51 insertions(+), 45 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/ptdump.h b/arch/arm64/include/asm/ptdump.h
> index 5b1701c76d1c..bd5d3ee3e8dc 100644
> --- a/arch/arm64/include/asm/ptdump.h
> +++ b/arch/arm64/include/asm/ptdump.h
> @@ -9,6 +9,7 @@
>  
>  #include <linux/mm_types.h>
>  #include <linux/seq_file.h>
> +#include <linux/ptdump.h>
>  
>  struct addr_marker {
>  	unsigned long start_address;
> @@ -21,14 +22,52 @@ struct ptdump_info {
>  	unsigned long			base_addr;
>  };
>  
> +struct ptdump_prot_bits {
> +	u64		mask;
> +	u64		val;
> +	const char	*set;
> +	const char	*clear;
> +};
> +
> +struct ptdump_pg_level {
> +	const struct ptdump_prot_bits *bits;
> +	char name[4];
> +	int num;
> +	u64 mask;
> +};
> +
> +/*
> + * The page dumper groups page table entries of the same type into a single
> + * description. It uses pg_state to track the range information while
> + * iterating over the pte entries. When the continuity is broken it then
> + * dumps out a description of the range.
> + */
> +struct ptdump_pg_state {
> +	struct ptdump_state ptdump;
> +	struct seq_file *seq;
> +	const struct addr_marker *marker;
> +	const struct mm_struct *mm;
> +	unsigned long start_address;
> +	int level;
> +	u64 current_prot;
> +	bool check_wx;
> +	unsigned long wx_pages;
> +	unsigned long uxn_pages;
> +};
> +
>  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);
>  #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);
>  #else
>  static inline void ptdump_debugfs_register(struct ptdump_info *info,
>  					   const char *name) { }
> -#endif
> +#endif /* CONFIG_PTDUMP_DEBUGFS */
> +#else
> +static inline void note_page(void *pt_st, unsigned long addr,
> +			     int level, u64 val) { }

nit: but why isn't 'pt_st' a pointer to 'struct ptdump_state'?

Perhaps you should #include <linux/ptdump.h> before the #ifdef
CONFIG_PTDUMP_CORE ?

In any case, the meat of the patch is fine:

Acked-by: Will Deacon <will@kernel.org>

Will
Re: [PATCH v10 2/5] arm64: ptdump: Expose the attribute parsing functionality
Posted by Marc Zyngier 2 months, 2 weeks ago 
On Tue, 10 Sep 2024 10:57:18 +0100,
Will Deacon <will@kernel.org> wrote:
> 
> On Mon, Sep 09, 2024 at 12:47:18PM +0000, Sebastian Ene wrote:
> > Reuse the descriptor parsing functionality to keep the same output format
> > as the original ptdump code. In order for this to happen, move the state
> > tracking objects into a common header.
> > 
> > Signed-off-by: Sebastian Ene <sebastianene@google.com>
> > ---
> >  arch/arm64/include/asm/ptdump.h | 41 +++++++++++++++++++++++-
> >  arch/arm64/mm/ptdump.c          | 55 +++++++--------------------------
> >  2 files changed, 51 insertions(+), 45 deletions(-)
> > 
> > diff --git a/arch/arm64/include/asm/ptdump.h b/arch/arm64/include/asm/ptdump.h
> > index 5b1701c76d1c..bd5d3ee3e8dc 100644
> > --- a/arch/arm64/include/asm/ptdump.h
> > +++ b/arch/arm64/include/asm/ptdump.h
> > @@ -9,6 +9,7 @@
> >  
> >  #include <linux/mm_types.h>
> >  #include <linux/seq_file.h>
> > +#include <linux/ptdump.h>
> >  
> >  struct addr_marker {
> >  	unsigned long start_address;
> > @@ -21,14 +22,52 @@ struct ptdump_info {
> >  	unsigned long			base_addr;
> >  };
> >  
> > +struct ptdump_prot_bits {
> > +	u64		mask;
> > +	u64		val;
> > +	const char	*set;
> > +	const char	*clear;
> > +};
> > +
> > +struct ptdump_pg_level {
> > +	const struct ptdump_prot_bits *bits;
> > +	char name[4];
> > +	int num;
> > +	u64 mask;
> > +};
> > +
> > +/*
> > + * The page dumper groups page table entries of the same type into a single
> > + * description. It uses pg_state to track the range information while
> > + * iterating over the pte entries. When the continuity is broken it then
> > + * dumps out a description of the range.
> > + */
> > +struct ptdump_pg_state {
> > +	struct ptdump_state ptdump;
> > +	struct seq_file *seq;
> > +	const struct addr_marker *marker;
> > +	const struct mm_struct *mm;
> > +	unsigned long start_address;
> > +	int level;
> > +	u64 current_prot;
> > +	bool check_wx;
> > +	unsigned long wx_pages;
> > +	unsigned long uxn_pages;
> > +};
> > +
> >  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);
> >  #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);
> >  #else
> >  static inline void ptdump_debugfs_register(struct ptdump_info *info,
> >  					   const char *name) { }
> > -#endif
> > +#endif /* CONFIG_PTDUMP_DEBUGFS */
> > +#else
> > +static inline void note_page(void *pt_st, unsigned long addr,
> > +			     int level, u64 val) { }
> 
> nit: but why isn't 'pt_st' a pointer to 'struct ptdump_state'?
> 
> Perhaps you should #include <linux/ptdump.h> before the #ifdef
> CONFIG_PTDUMP_CORE ?

Yup, that seems to do the trick. I'm folding this into the patch:

diff --git a/arch/arm64/include/asm/ptdump.h b/arch/arm64/include/asm/ptdump.h
index 71a7ed01153a4..6cf4aae052191 100644
--- a/arch/arm64/include/asm/ptdump.h
+++ b/arch/arm64/include/asm/ptdump.h
@@ -5,11 +5,12 @@
 #ifndef __ASM_PTDUMP_H
 #define __ASM_PTDUMP_H
 
+#include <linux/ptdump.h>
+
 #ifdef CONFIG_PTDUMP_CORE
 
 #include <linux/mm_types.h>
 #include <linux/seq_file.h>
-#include <linux/ptdump.h>
 
 struct addr_marker {
 	unsigned long start_address;
@@ -67,7 +68,7 @@ static inline void ptdump_debugfs_register(struct ptdump_info *info,
 					   const char *name) { }
 #endif /* CONFIG_PTDUMP_DEBUGFS */
 #else
-static inline void note_page(void *pt_st, unsigned long addr,
+static inline void note_page(struct ptdump_state *pt_st, unsigned long addr,
 			     int level, u64 val) { }
 #endif /* CONFIG_PTDUMP_CORE */
 
> In any case, the meat of the patch is fine:
> 
> Acked-by: Will Deacon <will@kernel.org>

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.

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