We used to only check the alignment of the physical address to decide
which mapping would fit for a certain region of the linear mapping, but
it is not enough since the virtual address must also be aligned, so check
that too.
Fixes: 3335068f8721 ("riscv: Use PUD/P4D/PGD pages for the linear mapping")
Reported-by: Song Shuai <[email protected]>
Link: https://lore.kernel.org/linux-riscv/[email protected]/
Signed-off-by: Alexandre Ghiti <[email protected]>
---
arch/riscv/mm/init.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index d42ea31c7de0..5143eef4c074 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -660,18 +660,19 @@ void __init create_pgd_mapping(pgd_t *pgdp,
create_pgd_next_mapping(nextp, va, pa, sz, prot);
}
-static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size)
+static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va,
+ phys_addr_t size)
{
- if (!(base & (PGDIR_SIZE - 1)) && size >= PGDIR_SIZE)
+ if (!(pa & (PGDIR_SIZE - 1)) && !(va & (PGDIR_SIZE - 1)) && size >= PGDIR_SIZE)
return PGDIR_SIZE;
- if (!(base & (P4D_SIZE - 1)) && size >= P4D_SIZE)
+ if (!(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE)
return P4D_SIZE;
- if (!(base & (PUD_SIZE - 1)) && size >= PUD_SIZE)
+ if (!(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE)
return PUD_SIZE;
- if (!(base & (PMD_SIZE - 1)) && size >= PMD_SIZE)
+ if (!(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE)
return PMD_SIZE;
return PAGE_SIZE;
@@ -1177,7 +1178,7 @@ static void __init create_linear_mapping_range(phys_addr_t start,
for (pa = start; pa < end; pa += map_size) {
va = (uintptr_t)__va(pa);
map_size = fixed_map_size ? fixed_map_size :
- best_map_size(pa, end - pa);
+ best_map_size(pa, va, end - pa);
create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
pgprot_from_va(va));
--
2.39.2
On 7 Jun 2023, at 13:58, Alexandre Ghiti <[email protected]> wrote:
>
> We used to only check the alignment of the physical address to decide
> which mapping would fit for a certain region of the linear mapping, but
> it is not enough since the virtual address must also be aligned, so check
> that too.
>
> Fixes: 3335068f8721 ("riscv: Use PUD/P4D/PGD pages for the linear mapping")
> Reported-by: Song Shuai <[email protected]>
> Link: https://lore.kernel.org/linux-riscv/[email protected]/
> Signed-off-by: Alexandre Ghiti <[email protected]>
> ---
> arch/riscv/mm/init.c | 13 +++++++------
> 1 file changed, 7 insertions(+), 6 deletions(-)
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index d42ea31c7de0..5143eef4c074 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -660,18 +660,19 @@ void __init create_pgd_mapping(pgd_t *pgdp,
> create_pgd_next_mapping(nextp, va, pa, sz, prot);
> }
>
> -static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size)
> +static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va,
Why on earth is this returning uintptr_t? It’s a size not a pointer.
Jess
> + phys_addr_t size)
> {
> - if (!(base & (PGDIR_SIZE - 1)) && size >= PGDIR_SIZE)
> + if (!(pa & (PGDIR_SIZE - 1)) && !(va & (PGDIR_SIZE - 1)) && size >= PGDIR_SIZE)
> return PGDIR_SIZE;
>
> - if (!(base & (P4D_SIZE - 1)) && size >= P4D_SIZE)
> + if (!(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE)
> return P4D_SIZE;
>
> - if (!(base & (PUD_SIZE - 1)) && size >= PUD_SIZE)
> + if (!(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE)
> return PUD_SIZE;
>
> - if (!(base & (PMD_SIZE - 1)) && size >= PMD_SIZE)
> + if (!(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE)
> return PMD_SIZE;
>
> return PAGE_SIZE;
> @@ -1177,7 +1178,7 @@ static void __init create_linear_mapping_range(phys_addr_t start,
> for (pa = start; pa < end; pa += map_size) {
> va = (uintptr_t)__va(pa);
> map_size = fixed_map_size ? fixed_map_size :
> - best_map_size(pa, end - pa);
> + best_map_size(pa, va, end - pa);
>
> create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
> pgprot_from_va(va));
> --
> 2.39.2
>
>
> _______________________________________________
> linux-riscv mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-riscv
On Wed, 07 Jun 2023 14:58:51 +0200, Alexandre Ghiti wrote:
> We used to only check the alignment of the physical address to decide
> which mapping would fit for a certain region of the linear mapping, but
> it is not enough since the virtual address must also be aligned, so check
> that too.
>
>
Applied, thanks!
[1/1] riscv: Check the virtual alignment before choosing a map size
https://git.kernel.org/palmer/c/49a0a3731596
Best regards,
--
Palmer Dabbelt <[email protected]>
Hello:
This patch was applied to riscv/linux.git (fixes)
by Palmer Dabbelt <[email protected]>:
On Wed, 7 Jun 2023 14:58:51 +0200 you wrote:
> We used to only check the alignment of the physical address to decide
> which mapping would fit for a certain region of the linear mapping, but
> it is not enough since the virtual address must also be aligned, so check
> that too.
>
> Fixes: 3335068f8721 ("riscv: Use PUD/P4D/PGD pages for the linear mapping")
> Reported-by: Song Shuai <[email protected]>
> Link: https://lore.kernel.org/linux-riscv/[email protected]/
> Signed-off-by: Alexandre Ghiti <[email protected]>
>
> [...]
Here is the summary with links:
- [-fixes] riscv: Check the virtual alignment before choosing a map size
https://git.kernel.org/riscv/c/49a0a3731596
You are awesome, thank you!
--
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