Provide a Kconfig option indicating if note_page can be called for
intermediate page directories during ptdump.
Signed-off-by: Maxwell Bland <mbland@motorola.com>
---
mm/Kconfig.debug | 9 +++++++++
mm/ptdump.c | 21 +++++++++++++--------
2 files changed, 22 insertions(+), 8 deletions(-)
diff --git a/mm/Kconfig.debug b/mm/Kconfig.debug
index afc72fde0f03..6af5ecfdef93 100644
--- a/mm/Kconfig.debug
+++ b/mm/Kconfig.debug
@@ -201,6 +201,15 @@ config PTDUMP_DEBUGFS
If in doubt, say N.
+config ARCH_SUPPORTS_NON_LEAF_PTDUMP
+ bool "Include intermediate directory entries in pagetable dumps"
+ default n
+ help
+ Enable the inclusion of intermediate page directory entries in calls
+ to the ptdump API. Once an architecture defines correct ptdump
+ behavior for PGD, PUD, P4D, and PMD entries, this config can be
+ selected.
+
config HAVE_DEBUG_KMEMLEAK
bool
diff --git a/mm/ptdump.c b/mm/ptdump.c
index 106e1d66e9f9..6180708669fe 100644
--- a/mm/ptdump.c
+++ b/mm/ptdump.c
@@ -41,10 +41,11 @@ static int ptdump_pgd_entry(pgd_t *pgd, unsigned long addr,
if (st->effective_prot)
st->effective_prot(st, 0, pgd_val(val));
- if (pgd_leaf(val)) {
+ if (IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP) || pgd_leaf(val))
st->note_page(st, addr, 0, pgd_val(val));
+
+ if (pgd_leaf(val))
walk->action = ACTION_CONTINUE;
- }
return 0;
}
@@ -64,10 +65,11 @@ static int ptdump_p4d_entry(p4d_t *p4d, unsigned long addr,
if (st->effective_prot)
st->effective_prot(st, 1, p4d_val(val));
- if (p4d_leaf(val)) {
+ if (IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP) || pgd_leaf(val))
st->note_page(st, addr, 1, p4d_val(val));
+
+ if (p4d_leaf(val))
walk->action = ACTION_CONTINUE;
- }
return 0;
}
@@ -87,10 +89,11 @@ static int ptdump_pud_entry(pud_t *pud, unsigned long addr,
if (st->effective_prot)
st->effective_prot(st, 2, pud_val(val));
- if (pud_leaf(val)) {
+ if (IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP) || pgd_leaf(val))
st->note_page(st, addr, 2, pud_val(val));
+
+ if (pud_leaf(val))
walk->action = ACTION_CONTINUE;
- }
return 0;
}
@@ -108,10 +111,12 @@ 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)) {
+
+ if (IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP) || pgd_leaf(val))
st->note_page(st, addr, 3, pmd_val(val));
+
+ if (pmd_leaf(val))
walk->action = ACTION_CONTINUE;
- }
return 0;
}
--
2.39.2
Le 18/06/2024 à 16:40, Maxwell Bland a écrit :
> [Vous ne recevez pas souvent de courriers de mbland@motorola.com. D?couvrez pourquoi ceci est important ? https://aka.ms/LearnAboutSenderIdentification ]
>
> Provide a Kconfig option indicating if note_page can be called for
> intermediate page directories during ptdump.
>
> Signed-off-by: Maxwell Bland <mbland@motorola.com>
> ---
> mm/Kconfig.debug | 9 +++++++++
> mm/ptdump.c | 21 +++++++++++++--------
> 2 files changed, 22 insertions(+), 8 deletions(-)
>
> diff --git a/mm/Kconfig.debug b/mm/Kconfig.debug
> index afc72fde0f03..6af5ecfdef93 100644
> --- a/mm/Kconfig.debug
> +++ b/mm/Kconfig.debug
> @@ -201,6 +201,15 @@ config PTDUMP_DEBUGFS
>
> If in doubt, say N.
>
> +config ARCH_SUPPORTS_NON_LEAF_PTDUMP
> + bool "Include intermediate directory entries in pagetable dumps"
> + default n
> + help
> + Enable the inclusion of intermediate page directory entries in calls
> + to the ptdump API. Once an architecture defines correct ptdump
> + behavior for PGD, PUD, P4D, and PMD entries, this config can be
> + selected.
> +
> config HAVE_DEBUG_KMEMLEAK
> bool
>
> diff --git a/mm/ptdump.c b/mm/ptdump.c
> index 106e1d66e9f9..6180708669fe 100644
> --- a/mm/ptdump.c
> +++ b/mm/ptdump.c
> @@ -41,10 +41,11 @@ static int ptdump_pgd_entry(pgd_t *pgd, unsigned long addr,
> if (st->effective_prot)
> st->effective_prot(st, 0, pgd_val(val));
>
> - if (pgd_leaf(val)) {
> + if (IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP) || pgd_leaf(val))
> st->note_page(st, addr, 0, pgd_val(val));
> +
> + if (pgd_leaf(val))
> walk->action = ACTION_CONTINUE;
> - }
>
> return 0;
> }
> @@ -64,10 +65,11 @@ static int ptdump_p4d_entry(p4d_t *p4d, unsigned long addr,
> if (st->effective_prot)
> st->effective_prot(st, 1, p4d_val(val));
>
> - if (p4d_leaf(val)) {
> + if (IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP) || pgd_leaf(val))
Don't you mean p4d_leaf() here instead of pgd_leaf() ?
> st->note_page(st, addr, 1, p4d_val(val));
> +
> + if (p4d_leaf(val))
> walk->action = ACTION_CONTINUE;
> - }
>
> return 0;
> }
> @@ -87,10 +89,11 @@ static int ptdump_pud_entry(pud_t *pud, unsigned long addr,
> if (st->effective_prot)
> st->effective_prot(st, 2, pud_val(val));
>
> - if (pud_leaf(val)) {
> + if (IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP) || pgd_leaf(val))
Don't you mean pud_leaf() here instead of pgd_leaf() ?
> st->note_page(st, addr, 2, pud_val(val));
> +
> + if (pud_leaf(val))
> walk->action = ACTION_CONTINUE;
> - }
>
> return 0;
> }
> @@ -108,10 +111,12 @@ 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)) {
> +
> + if (IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP) || pgd_leaf(val))
Don't you mean pmd_leaf() here instead of pgd_leaf() ?
> st->note_page(st, addr, 3, pmd_val(val));
> +
> + if (pmd_leaf(val))
> walk->action = ACTION_CONTINUE;
> - }
>
> return 0;
> }
> --
> 2.39.2
>
>
On Tue, Jun 18, 2024 at 06:38:24PM GMT, LEROY Christophe wrote:
> Le 18/06/2024 à 16:40, Maxwell Bland a écrit :
> > @@ -64,10 +65,11 @@ static int ptdump_p4d_entry(p4d_t *p4d, unsigned long addr,
> > if (st->effective_prot)
> > st->effective_prot(st, 1, p4d_val(val));
> >
> > - if (p4d_leaf(val)) {
> > + if (IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP) || pgd_leaf(val))
>
> Don't you mean p4d_leaf() here instead of pgd_leaf() ?
> Don't you mean pud_leaf() here instead of pgd_leaf() ?
> Don't you mean pmd_leaf() here instead of pgd_leaf() ?
Oh my, this is embarrassing. )-:
Hence the review process---thank you for catching these, will fix in v5.
Maxwell
Le 18/06/2024 à 21:41, Maxwell Bland a écrit :
> [Vous ne recevez pas souvent de courriers de mbland@motorola.com. Découvrez pourquoi ceci est important à https://aka.ms/LearnAboutSenderIdentification ]
>
> On Tue, Jun 18, 2024 at 06:38:24PM GMT, LEROY Christophe wrote:
>> Le 18/06/2024 à 16:40, Maxwell Bland a écrit :
>>> @@ -64,10 +65,11 @@ static int ptdump_p4d_entry(p4d_t *p4d, unsigned long addr,
>>> if (st->effective_prot)
>>> st->effective_prot(st, 1, p4d_val(val));
>>>
>>> - if (p4d_leaf(val)) {
>>> + if (IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP) || pgd_leaf(val))
>>
>> Don't you mean p4d_leaf() here instead of pgd_leaf() ?
>> Don't you mean pud_leaf() here instead of pgd_leaf() ?
>> Don't you mean pmd_leaf() here instead of pgd_leaf() ?
>
> Oh my, this is embarrassing. )-:
>
> Hence the review process---thank you for catching these, will fix in v5.
Maybe we could have a nicer code with something like:
static inline bool has_non_leaf_ptdump()
{
return IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP);
}
static int ptdump_p4d_entry(...)
{
...
if (has_non_leaf_ptdump() || pgd_leaf(val))
...
}
Christophe
On Wed, Jun 19, 2024 at 08:44:21AM GMT, LEROY Christophe wrote:
> Le 18/06/2024 à 21:41, Maxwell Bland a écrit :
> > On Tue, Jun 18, 2024 at 06:38:24PM GMT, LEROY Christophe wrote:
> >> Le 18/06/2024 à 16:40, Maxwell Bland a écrit :
> >> Don't you mean pmd_leaf() here instead of pgd_leaf() ?
> > thank you for catching these, will fix in v5.
>
> Maybe we could have a nicer code with something like:
>
> static inline bool has_non_leaf_ptdump()
> {
> return IS_ENABLED(CONFIG_ARCH_SUPPORTS_NON_LEAF_PTDUMP);
> }
>
> static int ptdump_p4d_entry(...)
> {
> ...
> if (has_non_leaf_ptdump() || pgd_leaf(val))
> ...
> }
Hi Christophe, nice, thank you! I incorporated this critique as well.
Forward pointer to v5:
https://lore.kernel.org/all/2bcb3htsjhepxdybpw2bwot2jnuezl3p5mnj5rhjwgitlsufe7@xzhkyntridw3/#t
Maxwell
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