2023-09-05 16:42:41

by Hongchen Zhang

Subject: [PATCH] LoongArch: add p?d_leaf() definitions

When I do LTP test, LTP test case ksm06 caused panic at
break_ksm_pmd_entry
-> pmd_leaf (Huge page table but False)
-> pte_present (panic)

The reason is pmd_leaf is not defined, So like
commit 501b81046701 ("mips: mm: add p?d_leaf() definitions")
add p?d_leaf() definition for LoongArch.

Signed-off-by: Hongchen Zhang <[email protected]>
---
arch/loongarch/include/asm/pgtable.h | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h
index 370c6568ceb8..ea54653b7aab 100644
--- a/arch/loongarch/include/asm/pgtable.h
+++ b/arch/loongarch/include/asm/pgtable.h
@@ -243,6 +243,9 @@ static inline void pmd_clear(pmd_t *pmdp)

#define pmd_phys(pmd) PHYSADDR(pmd_val(pmd))

+#define pmd_leaf(pmd) ((pmd_val(pmd) & _PAGE_HUGE) != 0)
+#define pud_leaf(pud) ((pud_val(pud) & _PAGE_HUGE) != 0)
+
#ifndef CONFIG_TRANSPARENT_HUGEPAGE
#define pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
--
2.33.0

2023-09-06 09:10:29

by David Hildenbrand

Subject: Re: [PATCH] LoongArch: add p?d_leaf() definitions

On 05.09.23 08:49, Hongchen Zhang wrote:
> When I do LTP test, LTP test case ksm06 caused panic at
> break_ksm_pmd_entry
> -> pmd_leaf (Huge page table but False)
> -> pte_present (panic)
>

Probably there are other problematic bits without that can trigger that?
I suspect walk_page_range*() callers might be affected,

> The reason is pmd_leaf is not defined, So like
> commit 501b81046701 ("mips: mm: add p?d_leaf() definitions")
> add p?d_leaf() definition for LoongArch.
>

We most certainly want to cc stable, no?

Can we come up with a Fixes: tag? Probably when we added THP support to
loongarch.

> Signed-off-by: Hongchen Zhang <[email protected]>
> ---
> arch/loongarch/include/asm/pgtable.h | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h
> index 370c6568ceb8..ea54653b7aab 100644
> --- a/arch/loongarch/include/asm/pgtable.h
> +++ b/arch/loongarch/include/asm/pgtable.h
> @@ -243,6 +243,9 @@ static inline void pmd_clear(pmd_t *pmdp)
>
> #define pmd_phys(pmd) PHYSADDR(pmd_val(pmd))
>
> +#define pmd_leaf(pmd) ((pmd_val(pmd) & _PAGE_HUGE) != 0)
> +#define pud_leaf(pud) ((pud_val(pud) & _PAGE_HUGE) != 0)
> +
> #ifndef CONFIG_TRANSPARENT_HUGEPAGE
> #define pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
> #endif /* CONFIG_TRANSPARENT_HUGEPAGE */

Acked-by: David Hildenbrand <[email protected]>

--
Cheers,

David / dhildenb