On Thu, Nov 12, 2026, at 12:54, Mike Rapoport wrote:
> On Thu, Nov 12, 2026 at 12:25:26PM +0100, Arnd Bergmann wrote:
>> From: Arnd Bergmann <[email protected]>
>>
>> With both x86 and arm having dropped CONFIG_HIGHPTE support, no
>> architecture is left using it, so remove the remnants in common code.
>>
>> It is likely that further cleanups are possible in the page table
>> code but those are not obvious from the config options.
>>
>> Signed-off-by: Arnd Bergmann <[email protected]>
>> ---
>> include/linux/hugetlb.h | 5 +----
>> include/linux/mm.h | 1 -
>> include/linux/pgtable.h | 9 ---------
>> 3 files changed, 1 insertion(+), 14 deletions(-)
>
> With this and arm HIGHPTE patches applied there are still a few leftovers:
>
> $ git grep HIGHPTE
> arch/arm/configs/vt8500_v6_v7_defconfig:CONFIG_HIGHPTE=y
This got dropped in patch 5/6 in v2, but I've moved that here now.
> mm/memory.c: * Dumping the PTE would be nice, but it's tricky with
> CONFIG_HIGHPTE,
Added the patch below for this. Untested so far.
> mm/pgtable-generic.c: * kmapped if necessary (when CONFIG_HIGHPTE), and
> locked against concurrent
Updated the comment and also dropped __pte_map() after I noticed that
open-coding the only caller in pte_offset_map_rw_nolock() is consistent
with that comment change:
--- a/mm/pgtable-generic.c
+++ b/mm/pgtable-generic.c
@@ -314,7 +314,7 @@ pte_t *__pte_offset_map(pmd_t *pmd, unsigned long addr,
pmd_t *pmdvalp)
pmd_clear_bad(pmd);
goto nomap;
}
- return __pte_map(&pmdval, addr);
+ return pte_offset_kernel(&pmdval, addr);
nomap:
rcu_read_unlock();
return NULL;
> mm/userfaultfd.c: * index ordering when CONFIG_HIGHPTE is
> enabled. We mapped dst_pte
Dropped that comment block as it no longer applies.
> Acked-by: Mike Rapoport (Microsoft) <[email protected]>
Thanks,
Arnd
---
Subject: [PATCH] mm: print pte in __print_bad_page_map_pgtable()
HIGHPTE support is gone now, so it's easy enough to print the
PTE here along with the upper level entries.
Signed-off-by: Arnd Bergmann <[email protected]>
diff --git a/mm/memory.c b/mm/memory.c
index ec3d9d99ccee..dabeb5568c94 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -528,9 +528,11 @@ static void __print_bad_page_map_pgtable(struct mm_struct
*mm, unsigned long add
char p4d_str[PTVAL_STR_MAX];
char pud_str[PTVAL_STR_MAX];
char pmd_str[PTVAL_STR_MAX];
+ char pte_str[PTVAL_STR_MAX];
p4d_t p4d, *p4dp;
pud_t pud, *pudp;
pmd_t pmd, *pmdp;
+ pte_t pte, *ptep;
pgd_t *pgdp;
/*
@@ -567,13 +569,18 @@ static void __print_bad_page_map_pgtable(struct mm_struct
*mm, unsigned long add
pmd = pmdp_get(pmdp);
ptval_to_str(pmd_str, pmd_val(pmd));
- /*
- * Dumping the PTE would be nice, but it's tricky with CONFIG_HIGHPTE,
- * because the table should already be mapped by the caller and
- * doing another map would be bad. print_bad_page_map() should
- * already take care of printing the PTE.
- */
- pr_alert("pgd:%s p4d:%s pud:%s pmd:%s\n", pgd_str, p4d_str, pud_str,
pmd_str);
+ if (!pmd_present(pmd) || pmd_leaf(pmd)) {
+ pr_alert("pgd:%s p4d:%s pud:%s pmd: %s\n",
+ pgd_str, p4d_str, pud_str, pmd_str);
+ return;
+ }
+
+ ptep = pte_offset_kernel(pmdp, addr);
+ pte = ptep_get(ptep);
+ ptval_to_str(pte_str, pte_val(pte));
+
+ pr_alert("pgd:%s p4d:%s pud:%s pmd:%s pte:%s\n",
+ pgd_str, p4d_str, pud_str, pmd_str, pte_str);
}
/*
