2022-06-23 08:59:30

by Christophe Leroy

Subject: [PATCH] powerpc/book3e: Fix PUD allocation size in map_kernel_page()

Commit 2fb4706057bc ("powerpc: add support for folded p4d page tables")
erroneously changed PUD setup to a mix of PMD and PUD. Fix it.

While at it, use PTE_TABLE_SIZE instead of PAGE_SIZE for PTE tables
in order to avoid any confusion.

Fixes: 2fb4706057bc ("powerpc: add support for folded p4d page tables")
Cc: [email protected]
Cc: Mike Rapoport <[email protected]>
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/mm/nohash/book3e_pgtable.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/mm/nohash/book3e_pgtable.c b/arch/powerpc/mm/nohash/book3e_pgtable.c
index 7d4368d055a6..b80fc4a91a53 100644
--- a/arch/powerpc/mm/nohash/book3e_pgtable.c
+++ b/arch/powerpc/mm/nohash/book3e_pgtable.c
@@ -96,8 +96,8 @@ int __ref map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot)
pgdp = pgd_offset_k(ea);
p4dp = p4d_offset(pgdp, ea);
if (p4d_none(*p4dp)) {
- pmdp = early_alloc_pgtable(PMD_TABLE_SIZE);
- p4d_populate(&init_mm, p4dp, pmdp);
+ pudp = early_alloc_pgtable(PUD_TABLE_SIZE);
+ p4d_populate(&init_mm, p4dp, pudp);
}
pudp = pud_offset(p4dp, ea);
if (pud_none(*pudp)) {
@@ -106,7 +106,7 @@ int __ref map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot)
}
pmdp = pmd_offset(pudp, ea);
if (!pmd_present(*pmdp)) {
- ptep = early_alloc_pgtable(PAGE_SIZE);
+ ptep = early_alloc_pgtable(PTE_TABLE_SIZE);
pmd_populate_kernel(&init_mm, pmdp, ptep);
}
ptep = pte_offset_kernel(pmdp, ea);
--
2.36.1

2022-06-23 19:08:40

by Mike Rapoport

Subject: Re: [PATCH] powerpc/book3e: Fix PUD allocation size in map_kernel_page()

On Thu, Jun 23, 2022 at 10:56:17AM +0200, Christophe Leroy wrote:
> Commit 2fb4706057bc ("powerpc: add support for folded p4d page tables")
> erroneously changed PUD setup to a mix of PMD and PUD. Fix it.
>
> While at it, use PTE_TABLE_SIZE instead of PAGE_SIZE for PTE tables
> in order to avoid any confusion.
>
> Fixes: 2fb4706057bc ("powerpc: add support for folded p4d page tables")
> Cc: [email protected]
> Cc: Mike Rapoport <[email protected]>
> Signed-off-by: Christophe Leroy <[email protected]>

Acked-by: Mike Rapoport <[email protected]>

> ---
> arch/powerpc/mm/nohash/book3e_pgtable.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/powerpc/mm/nohash/book3e_pgtable.c b/arch/powerpc/mm/nohash/book3e_pgtable.c
> index 7d4368d055a6..b80fc4a91a53 100644
> --- a/arch/powerpc/mm/nohash/book3e_pgtable.c
> +++ b/arch/powerpc/mm/nohash/book3e_pgtable.c
> @@ -96,8 +96,8 @@ int __ref map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot)
> pgdp = pgd_offset_k(ea);
> p4dp = p4d_offset(pgdp, ea);
> if (p4d_none(*p4dp)) {
> - pmdp = early_alloc_pgtable(PMD_TABLE_SIZE);
> - p4d_populate(&init_mm, p4dp, pmdp);
> + pudp = early_alloc_pgtable(PUD_TABLE_SIZE);
> + p4d_populate(&init_mm, p4dp, pudp);
> }
> pudp = pud_offset(p4dp, ea);
> if (pud_none(*pudp)) {
> @@ -106,7 +106,7 @@ int __ref map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot)
> }
> pmdp = pmd_offset(pudp, ea);
> if (!pmd_present(*pmdp)) {
> - ptep = early_alloc_pgtable(PAGE_SIZE);
> + ptep = early_alloc_pgtable(PTE_TABLE_SIZE);
> pmd_populate_kernel(&init_mm, pmdp, ptep);
> }
> ptep = pte_offset_kernel(pmdp, ea);
> --
> 2.36.1
>

--
Sincerely yours,
Mike.

2022-06-29 07:05:55

by Michael Ellerman

Subject: Re: [PATCH] powerpc/book3e: Fix PUD allocation size in map_kernel_page()

On Thu, 23 Jun 2022 10:56:17 +0200, Christophe Leroy wrote:
> Commit 2fb4706057bc ("powerpc: add support for folded p4d page tables")
> erroneously changed PUD setup to a mix of PMD and PUD. Fix it.
>
> While at it, use PTE_TABLE_SIZE instead of PAGE_SIZE for PTE tables
> in order to avoid any confusion.
>
>
> [...]

Applied to powerpc/fixes.

[1/1] powerpc/book3e: Fix PUD allocation size in map_kernel_page()
https://git.kernel.org/powerpc/c/986481618023e18e187646b0fff05a3c337531cb

cheers