* [PATCH v2] ARM: mm: report both sections from PMD
@ 2014-02-12 22:46 ` Kees Cook
0 siblings, 0 replies; 8+ messages in thread
From: Kees Cook @ 2014-02-12 22:46 UTC (permalink / raw)
To: Russell King
Cc: Catalin Marinas, Will Deacon, Steven Capper, Christoffer Dall,
Kees Cook, Marc Zyngier, Laura Abbott, linux-arm-kernel,
linux-kernel
On 2-level page table systems, the PMD has 2 section entries. Report
these, otherwise ARM_PTDUMP will miss reporting permission changes on
odd section boundaries.
Signed-off-by: Kees Cook <keescook@chromium.org>
---
v2:
- reorganize, suggested by Catalin Marinas.
---
arch/arm/include/asm/pgtable-3level.h | 4 ----
arch/arm/include/asm/pgtable.h | 4 ++++
arch/arm/mm/dump.c | 8 +++++++-
3 files changed, 11 insertions(+), 5 deletions(-)
diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index 03243f7eeddf..fb3de59ee811 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -138,10 +138,6 @@
#define pud_none(pud) (!pud_val(pud))
#define pud_bad(pud) (!(pud_val(pud) & 2))
#define pud_present(pud) (pud_val(pud))
-#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
- PMD_TYPE_TABLE)
-#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
- PMD_TYPE_SECT)
#define pmd_large(pmd) pmd_sect(pmd)
#define pud_clear(pudp) \
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index 7d59b524f2af..934aa5b60c7c 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -183,6 +183,10 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
#define pmd_none(pmd) (!pmd_val(pmd))
#define pmd_present(pmd) (pmd_val(pmd))
+#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
+ PMD_TYPE_TABLE)
+#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
+ PMD_TYPE_SECT)
static inline pte_t *pmd_page_vaddr(pmd_t pmd)
{
diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c
index 2b342177f5de..32635b474832 100644
--- a/arch/arm/mm/dump.c
+++ b/arch/arm/mm/dump.c
@@ -260,8 +260,14 @@ static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start)
for (i = 0; i < PTRS_PER_PMD; i++, pmd++) {
addr = start + i * PMD_SIZE;
- if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd))
+ if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd)) {
note_page(st, addr, 3, pmd_val(*pmd));
+ if (SECTION_SIZE < PMD_SIZE &&
+ pmd_sect(*pmd) && pmd_sect(pmd[1])) {
+ note_page(st, addr + SECTION_SIZE, 3,
+ pmd_val(pmd[1]));
+ }
+ }
else
walk_pte(st, pmd, addr);
}
--
1.7.9.5
--
Kees Cook
Chrome OS Security
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v2] ARM: mm: report both sections from PMD
@ 2014-02-12 22:46 ` Kees Cook
0 siblings, 0 replies; 8+ messages in thread
From: Kees Cook @ 2014-02-12 22:46 UTC (permalink / raw)
To: linux-arm-kernel
On 2-level page table systems, the PMD has 2 section entries. Report
these, otherwise ARM_PTDUMP will miss reporting permission changes on
odd section boundaries.
Signed-off-by: Kees Cook <keescook@chromium.org>
---
v2:
- reorganize, suggested by Catalin Marinas.
---
arch/arm/include/asm/pgtable-3level.h | 4 ----
arch/arm/include/asm/pgtable.h | 4 ++++
arch/arm/mm/dump.c | 8 +++++++-
3 files changed, 11 insertions(+), 5 deletions(-)
diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index 03243f7eeddf..fb3de59ee811 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -138,10 +138,6 @@
#define pud_none(pud) (!pud_val(pud))
#define pud_bad(pud) (!(pud_val(pud) & 2))
#define pud_present(pud) (pud_val(pud))
-#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
- PMD_TYPE_TABLE)
-#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
- PMD_TYPE_SECT)
#define pmd_large(pmd) pmd_sect(pmd)
#define pud_clear(pudp) \
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index 7d59b524f2af..934aa5b60c7c 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -183,6 +183,10 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
#define pmd_none(pmd) (!pmd_val(pmd))
#define pmd_present(pmd) (pmd_val(pmd))
+#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
+ PMD_TYPE_TABLE)
+#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
+ PMD_TYPE_SECT)
static inline pte_t *pmd_page_vaddr(pmd_t pmd)
{
diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c
index 2b342177f5de..32635b474832 100644
--- a/arch/arm/mm/dump.c
+++ b/arch/arm/mm/dump.c
@@ -260,8 +260,14 @@ static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start)
for (i = 0; i < PTRS_PER_PMD; i++, pmd++) {
addr = start + i * PMD_SIZE;
- if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd))
+ if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd)) {
note_page(st, addr, 3, pmd_val(*pmd));
+ if (SECTION_SIZE < PMD_SIZE &&
+ pmd_sect(*pmd) && pmd_sect(pmd[1])) {
+ note_page(st, addr + SECTION_SIZE, 3,
+ pmd_val(pmd[1]));
+ }
+ }
else
walk_pte(st, pmd, addr);
}
--
1.7.9.5
--
Kees Cook
Chrome OS Security
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH v2] ARM: mm: report both sections from PMD
2014-02-12 22:46 ` Kees Cook
@ 2014-02-13 17:12 ` Catalin Marinas
-1 siblings, 0 replies; 8+ messages in thread
From: Catalin Marinas @ 2014-02-13 17:12 UTC (permalink / raw)
To: Kees Cook
Cc: Russell King, Will Deacon, Steven Capper, Christoffer Dall,
Marc Zyngier, Laura Abbott, linux-arm-kernel, linux-kernel
On Wed, Feb 12, 2014 at 10:46:38PM +0000, Kees Cook wrote:
> diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
> index 03243f7eeddf..fb3de59ee811 100644
> --- a/arch/arm/include/asm/pgtable-3level.h
> +++ b/arch/arm/include/asm/pgtable-3level.h
> @@ -138,10 +138,6 @@
> #define pud_none(pud) (!pud_val(pud))
> #define pud_bad(pud) (!(pud_val(pud) & 2))
> #define pud_present(pud) (pud_val(pud))
> -#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> - PMD_TYPE_TABLE)
> -#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> - PMD_TYPE_SECT)
> #define pmd_large(pmd) pmd_sect(pmd)
>
> #define pud_clear(pudp) \
> diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
> index 7d59b524f2af..934aa5b60c7c 100644
> --- a/arch/arm/include/asm/pgtable.h
> +++ b/arch/arm/include/asm/pgtable.h
> @@ -183,6 +183,10 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
>
> #define pmd_none(pmd) (!pmd_val(pmd))
> #define pmd_present(pmd) (pmd_val(pmd))
> +#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> + PMD_TYPE_TABLE)
> +#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> + PMD_TYPE_SECT)
Do you still need to move these two if you only use pmd_large()? AFAICT,
it is equivalent to pmd_sect().
> static inline pte_t *pmd_page_vaddr(pmd_t pmd)
> {
> diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c
> index 2b342177f5de..32635b474832 100644
> --- a/arch/arm/mm/dump.c
> +++ b/arch/arm/mm/dump.c
> @@ -260,8 +260,14 @@ static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start)
>
> for (i = 0; i < PTRS_PER_PMD; i++, pmd++) {
> addr = start + i * PMD_SIZE;
> - if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd))
> + if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd)) {
> note_page(st, addr, 3, pmd_val(*pmd));
> + if (SECTION_SIZE < PMD_SIZE &&
> + pmd_sect(*pmd) && pmd_sect(pmd[1])) {
I think the first patch was better with pmd[0] and pmd[1] treated
independently if SECTION_SIZE < PMD_SIZE, only that it should have
checked for pmd_sect(pmd[1]). I don't see anything in
__map_init_section() that would prevent populating only the second pmd
leaving the first one empty.
--
Catalin
^ permalink raw reply [flat|nested] 8+ messages in thread* [PATCH v2] ARM: mm: report both sections from PMD
@ 2014-02-13 17:12 ` Catalin Marinas
0 siblings, 0 replies; 8+ messages in thread
From: Catalin Marinas @ 2014-02-13 17:12 UTC (permalink / raw)
To: linux-arm-kernel
On Wed, Feb 12, 2014 at 10:46:38PM +0000, Kees Cook wrote:
> diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
> index 03243f7eeddf..fb3de59ee811 100644
> --- a/arch/arm/include/asm/pgtable-3level.h
> +++ b/arch/arm/include/asm/pgtable-3level.h
> @@ -138,10 +138,6 @@
> #define pud_none(pud) (!pud_val(pud))
> #define pud_bad(pud) (!(pud_val(pud) & 2))
> #define pud_present(pud) (pud_val(pud))
> -#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> - PMD_TYPE_TABLE)
> -#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> - PMD_TYPE_SECT)
> #define pmd_large(pmd) pmd_sect(pmd)
>
> #define pud_clear(pudp) \
> diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
> index 7d59b524f2af..934aa5b60c7c 100644
> --- a/arch/arm/include/asm/pgtable.h
> +++ b/arch/arm/include/asm/pgtable.h
> @@ -183,6 +183,10 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
>
> #define pmd_none(pmd) (!pmd_val(pmd))
> #define pmd_present(pmd) (pmd_val(pmd))
> +#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> + PMD_TYPE_TABLE)
> +#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> + PMD_TYPE_SECT)
Do you still need to move these two if you only use pmd_large()? AFAICT,
it is equivalent to pmd_sect().
> static inline pte_t *pmd_page_vaddr(pmd_t pmd)
> {
> diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c
> index 2b342177f5de..32635b474832 100644
> --- a/arch/arm/mm/dump.c
> +++ b/arch/arm/mm/dump.c
> @@ -260,8 +260,14 @@ static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start)
>
> for (i = 0; i < PTRS_PER_PMD; i++, pmd++) {
> addr = start + i * PMD_SIZE;
> - if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd))
> + if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd)) {
> note_page(st, addr, 3, pmd_val(*pmd));
> + if (SECTION_SIZE < PMD_SIZE &&
> + pmd_sect(*pmd) && pmd_sect(pmd[1])) {
I think the first patch was better with pmd[0] and pmd[1] treated
independently if SECTION_SIZE < PMD_SIZE, only that it should have
checked for pmd_sect(pmd[1]). I don't see anything in
__map_init_section() that would prevent populating only the second pmd
leaving the first one empty.
--
Catalin
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH v2] ARM: mm: report both sections from PMD
2014-02-13 17:12 ` Catalin Marinas
@ 2014-02-13 19:52 ` Kees Cook
-1 siblings, 0 replies; 8+ messages in thread
From: Kees Cook @ 2014-02-13 19:52 UTC (permalink / raw)
To: Catalin Marinas
Cc: Russell King, Will Deacon, Steven Capper, Christoffer Dall,
Marc Zyngier, Laura Abbott, linux-arm-kernel, linux-kernel
On Thu, Feb 13, 2014 at 9:12 AM, Catalin Marinas
<catalin.marinas@arm.com> wrote:
> On Wed, Feb 12, 2014 at 10:46:38PM +0000, Kees Cook wrote:
>> diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
>> index 03243f7eeddf..fb3de59ee811 100644
>> --- a/arch/arm/include/asm/pgtable-3level.h
>> +++ b/arch/arm/include/asm/pgtable-3level.h
>> @@ -138,10 +138,6 @@
>> #define pud_none(pud) (!pud_val(pud))
>> #define pud_bad(pud) (!(pud_val(pud) & 2))
>> #define pud_present(pud) (pud_val(pud))
>> -#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
>> - PMD_TYPE_TABLE)
>> -#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
>> - PMD_TYPE_SECT)
>> #define pmd_large(pmd) pmd_sect(pmd)
>>
>> #define pud_clear(pudp) \
>> diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
>> index 7d59b524f2af..934aa5b60c7c 100644
>> --- a/arch/arm/include/asm/pgtable.h
>> +++ b/arch/arm/include/asm/pgtable.h
>> @@ -183,6 +183,10 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
>>
>> #define pmd_none(pmd) (!pmd_val(pmd))
>> #define pmd_present(pmd) (pmd_val(pmd))
>> +#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
>> + PMD_TYPE_TABLE)
>> +#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
>> + PMD_TYPE_SECT)
>
> Do you still need to move these two if you only use pmd_large()? AFAICT,
> it is equivalent to pmd_sect().
Why does pmd_sect exist? I can reduce it to just using pmd_large.
>
>> static inline pte_t *pmd_page_vaddr(pmd_t pmd)
>> {
>> diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c
>> index 2b342177f5de..32635b474832 100644
>> --- a/arch/arm/mm/dump.c
>> +++ b/arch/arm/mm/dump.c
>> @@ -260,8 +260,14 @@ static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start)
>>
>> for (i = 0; i < PTRS_PER_PMD; i++, pmd++) {
>> addr = start + i * PMD_SIZE;
>> - if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd))
>> + if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd)) {
>> note_page(st, addr, 3, pmd_val(*pmd));
>> + if (SECTION_SIZE < PMD_SIZE &&
>> + pmd_sect(*pmd) && pmd_sect(pmd[1])) {
>
> I think the first patch was better with pmd[0] and pmd[1] treated
> independently if SECTION_SIZE < PMD_SIZE, only that it should have
> checked for pmd_sect(pmd[1]). I don't see anything in
> __map_init_section() that would prevent populating only the second pmd
> leaving the first one empty.
Ah, gotcha. Okay, I will send a new version. Thanks!
-Kees
--
Kees Cook
Chrome OS Security
^ permalink raw reply [flat|nested] 8+ messages in thread* [PATCH v2] ARM: mm: report both sections from PMD
@ 2014-02-13 19:52 ` Kees Cook
0 siblings, 0 replies; 8+ messages in thread
From: Kees Cook @ 2014-02-13 19:52 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, Feb 13, 2014 at 9:12 AM, Catalin Marinas
<catalin.marinas@arm.com> wrote:
> On Wed, Feb 12, 2014 at 10:46:38PM +0000, Kees Cook wrote:
>> diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
>> index 03243f7eeddf..fb3de59ee811 100644
>> --- a/arch/arm/include/asm/pgtable-3level.h
>> +++ b/arch/arm/include/asm/pgtable-3level.h
>> @@ -138,10 +138,6 @@
>> #define pud_none(pud) (!pud_val(pud))
>> #define pud_bad(pud) (!(pud_val(pud) & 2))
>> #define pud_present(pud) (pud_val(pud))
>> -#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
>> - PMD_TYPE_TABLE)
>> -#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
>> - PMD_TYPE_SECT)
>> #define pmd_large(pmd) pmd_sect(pmd)
>>
>> #define pud_clear(pudp) \
>> diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
>> index 7d59b524f2af..934aa5b60c7c 100644
>> --- a/arch/arm/include/asm/pgtable.h
>> +++ b/arch/arm/include/asm/pgtable.h
>> @@ -183,6 +183,10 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
>>
>> #define pmd_none(pmd) (!pmd_val(pmd))
>> #define pmd_present(pmd) (pmd_val(pmd))
>> +#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
>> + PMD_TYPE_TABLE)
>> +#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
>> + PMD_TYPE_SECT)
>
> Do you still need to move these two if you only use pmd_large()? AFAICT,
> it is equivalent to pmd_sect().
Why does pmd_sect exist? I can reduce it to just using pmd_large.
>
>> static inline pte_t *pmd_page_vaddr(pmd_t pmd)
>> {
>> diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c
>> index 2b342177f5de..32635b474832 100644
>> --- a/arch/arm/mm/dump.c
>> +++ b/arch/arm/mm/dump.c
>> @@ -260,8 +260,14 @@ static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start)
>>
>> for (i = 0; i < PTRS_PER_PMD; i++, pmd++) {
>> addr = start + i * PMD_SIZE;
>> - if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd))
>> + if (pmd_none(*pmd) || pmd_large(*pmd) || !pmd_present(*pmd)) {
>> note_page(st, addr, 3, pmd_val(*pmd));
>> + if (SECTION_SIZE < PMD_SIZE &&
>> + pmd_sect(*pmd) && pmd_sect(pmd[1])) {
>
> I think the first patch was better with pmd[0] and pmd[1] treated
> independently if SECTION_SIZE < PMD_SIZE, only that it should have
> checked for pmd_sect(pmd[1]). I don't see anything in
> __map_init_section() that would prevent populating only the second pmd
> leaving the first one empty.
Ah, gotcha. Okay, I will send a new version. Thanks!
-Kees
--
Kees Cook
Chrome OS Security
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH v2] ARM: mm: report both sections from PMD
2014-02-13 19:52 ` Kees Cook
@ 2014-02-14 10:15 ` Catalin Marinas
-1 siblings, 0 replies; 8+ messages in thread
From: Catalin Marinas @ 2014-02-14 10:15 UTC (permalink / raw)
To: Kees Cook
Cc: Russell King, Will Deacon, Steven Capper, Christoffer Dall,
Marc Zyngier, Laura Abbott, linux-arm-kernel, linux-kernel
On Thu, Feb 13, 2014 at 07:52:03PM +0000, Kees Cook wrote:
> On Thu, Feb 13, 2014 at 9:12 AM, Catalin Marinas
> <catalin.marinas@arm.com> wrote:
> > On Wed, Feb 12, 2014 at 10:46:38PM +0000, Kees Cook wrote:
> >> diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
> >> index 03243f7eeddf..fb3de59ee811 100644
> >> --- a/arch/arm/include/asm/pgtable-3level.h
> >> +++ b/arch/arm/include/asm/pgtable-3level.h
> >> @@ -138,10 +138,6 @@
> >> #define pud_none(pud) (!pud_val(pud))
> >> #define pud_bad(pud) (!(pud_val(pud) & 2))
> >> #define pud_present(pud) (pud_val(pud))
> >> -#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> >> - PMD_TYPE_TABLE)
> >> -#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> >> - PMD_TYPE_SECT)
> >> #define pmd_large(pmd) pmd_sect(pmd)
> >>
> >> #define pud_clear(pudp) \
> >> diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
> >> index 7d59b524f2af..934aa5b60c7c 100644
> >> --- a/arch/arm/include/asm/pgtable.h
> >> +++ b/arch/arm/include/asm/pgtable.h
> >> @@ -183,6 +183,10 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
> >>
> >> #define pmd_none(pmd) (!pmd_val(pmd))
> >> #define pmd_present(pmd) (pmd_val(pmd))
> >> +#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> >> + PMD_TYPE_TABLE)
> >> +#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> >> + PMD_TYPE_SECT)
> >
> > Do you still need to move these two if you only use pmd_large()? AFAICT,
> > it is equivalent to pmd_sect().
>
> Why does pmd_sect exist? I can reduce it to just using pmd_large.
pmd_sect/pmd_table were there first and used by kvm. The pmd_large() was
added by Russell because the dump.c code was derived from x86 which uses
such macro. And we have another close relative, pmd_huge(), though only
defined if CONFIG_HUGETLB_PAGE.
We could drop pmd_large() in favour of pmd_sect() but it's up to
Russell. OTOH, when someone will try to add arm64 support, I'll most
likely ask for part of the x86 code to be turned into a generic library
and we'll need some common naming for such macros (e.g. pmd_large()).
--
Catalin
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v2] ARM: mm: report both sections from PMD
@ 2014-02-14 10:15 ` Catalin Marinas
0 siblings, 0 replies; 8+ messages in thread
From: Catalin Marinas @ 2014-02-14 10:15 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, Feb 13, 2014 at 07:52:03PM +0000, Kees Cook wrote:
> On Thu, Feb 13, 2014 at 9:12 AM, Catalin Marinas
> <catalin.marinas@arm.com> wrote:
> > On Wed, Feb 12, 2014 at 10:46:38PM +0000, Kees Cook wrote:
> >> diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
> >> index 03243f7eeddf..fb3de59ee811 100644
> >> --- a/arch/arm/include/asm/pgtable-3level.h
> >> +++ b/arch/arm/include/asm/pgtable-3level.h
> >> @@ -138,10 +138,6 @@
> >> #define pud_none(pud) (!pud_val(pud))
> >> #define pud_bad(pud) (!(pud_val(pud) & 2))
> >> #define pud_present(pud) (pud_val(pud))
> >> -#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> >> - PMD_TYPE_TABLE)
> >> -#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> >> - PMD_TYPE_SECT)
> >> #define pmd_large(pmd) pmd_sect(pmd)
> >>
> >> #define pud_clear(pudp) \
> >> diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
> >> index 7d59b524f2af..934aa5b60c7c 100644
> >> --- a/arch/arm/include/asm/pgtable.h
> >> +++ b/arch/arm/include/asm/pgtable.h
> >> @@ -183,6 +183,10 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
> >>
> >> #define pmd_none(pmd) (!pmd_val(pmd))
> >> #define pmd_present(pmd) (pmd_val(pmd))
> >> +#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> >> + PMD_TYPE_TABLE)
> >> +#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
> >> + PMD_TYPE_SECT)
> >
> > Do you still need to move these two if you only use pmd_large()? AFAICT,
> > it is equivalent to pmd_sect().
>
> Why does pmd_sect exist? I can reduce it to just using pmd_large.
pmd_sect/pmd_table were there first and used by kvm. The pmd_large() was
added by Russell because the dump.c code was derived from x86 which uses
such macro. And we have another close relative, pmd_huge(), though only
defined if CONFIG_HUGETLB_PAGE.
We could drop pmd_large() in favour of pmd_sect() but it's up to
Russell. OTOH, when someone will try to add arm64 support, I'll most
likely ask for part of the x86 code to be turned into a generic library
and we'll need some common naming for such macros (e.g. pmd_large()).
--
Catalin
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2014-02-14 10:15 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-02-12 22:46 [PATCH v2] ARM: mm: report both sections from PMD Kees Cook
2014-02-12 22:46 ` Kees Cook
2014-02-13 17:12 ` Catalin Marinas
2014-02-13 17:12 ` Catalin Marinas
2014-02-13 19:52 ` Kees Cook
2014-02-13 19:52 ` Kees Cook
2014-02-14 10:15 ` Catalin Marinas
2014-02-14 10:15 ` Catalin Marinas
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