From: "Mike Rapoport (IBM)" <[email protected]>
nios2 uses kmalloc() to implement module_alloc() because CALL26/PCREL26
cannot reach all of vmalloc address space.
Define module space as 32MiB below the kernel base and switch nios2 to
use vmalloc for module allocations.
Suggested-by: Thomas Gleixner <[email protected]>
Signed-off-by: Mike Rapoport (IBM) <[email protected]>
Acked-by: Dinh Nguyen <[email protected]>
---
arch/nios2/include/asm/pgtable.h | 5 ++++-
arch/nios2/kernel/module.c | 19 ++++---------------
2 files changed, 8 insertions(+), 16 deletions(-)
diff --git a/arch/nios2/include/asm/pgtable.h b/arch/nios2/include/asm/pgtable.h
index 0f5c2564e9f5..0073b289c6a4 100644
--- a/arch/nios2/include/asm/pgtable.h
+++ b/arch/nios2/include/asm/pgtable.h
@@ -25,7 +25,10 @@
#include <asm-generic/pgtable-nopmd.h>
#define VMALLOC_START CONFIG_NIOS2_KERNEL_MMU_REGION_BASE
-#define VMALLOC_END (CONFIG_NIOS2_KERNEL_REGION_BASE - 1)
+#define VMALLOC_END (CONFIG_NIOS2_KERNEL_REGION_BASE - SZ_32M - 1)
+
+#define MODULES_VADDR (CONFIG_NIOS2_KERNEL_REGION_BASE - SZ_32M)
+#define MODULES_END (CONFIG_NIOS2_KERNEL_REGION_BASE - 1)
struct mm_struct;
diff --git a/arch/nios2/kernel/module.c b/arch/nios2/kernel/module.c
index 76e0a42d6e36..9c97b7513853 100644
--- a/arch/nios2/kernel/module.c
+++ b/arch/nios2/kernel/module.c
@@ -21,23 +21,12 @@
#include <asm/cacheflush.h>
-/*
- * Modules should NOT be allocated with kmalloc for (obvious) reasons.
- * But we do it for now to avoid relocation issues. CALL26/PCREL26 cannot reach
- * from 0x80000000 (vmalloc area) to 0xc00000000 (kernel) (kmalloc returns
- * addresses in 0xc0000000)
- */
void *module_alloc(unsigned long size)
{
- if (size == 0)
- return NULL;
- return kmalloc(size, GFP_KERNEL);
-}
-
-/* Free memory returned from module_alloc */
-void module_memfree(void *module_region)
-{
- kfree(module_region);
+ return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
+ GFP_KERNEL, PAGE_KERNEL_EXEC,
+ VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
+ __builtin_return_address(0));
}
int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
--
2.35.1
On Fri, 2023-06-16 at 11:50 +0300, Mike Rapoport wrote:
> void *module_alloc(unsigned long size)
> {
> - if (size == 0)
> - return NULL;
> - return kmalloc(size, GFP_KERNEL);
> -}
> -
> -/* Free memory returned from module_alloc */
> -void module_memfree(void *module_region)
> -{
> - kfree(module_region);
> + return __vmalloc_node_range(size, 1, MODULES_VADDR,
> MODULES_END,
> + GFP_KERNEL, PAGE_KERNEL_EXEC,
> + VM_FLUSH_RESET_PERMS,
> NUMA_NO_NODE,
> + __builtin_return_address(0));
> }
>
> int apply_relocate_add(Elf32_Shdr *sechdrs, const char *s
I wonder if the (size == 0) check is really needed, but
__vmalloc_node_range() will WARN on this case where the old code won't.
On Fri, Jun 16, 2023 at 1:51 AM Mike Rapoport <[email protected]> wrote:
>
> From: "Mike Rapoport (IBM)" <[email protected]>
>
> nios2 uses kmalloc() to implement module_alloc() because CALL26/PCREL26
> cannot reach all of vmalloc address space.
>
> Define module space as 32MiB below the kernel base and switch nios2 to
> use vmalloc for module allocations.
>
> Suggested-by: Thomas Gleixner <[email protected]>
> Signed-off-by: Mike Rapoport (IBM) <[email protected]>
> Acked-by: Dinh Nguyen <[email protected]>
Acked-by: Song Liu <[email protected]>
> ---
> arch/nios2/include/asm/pgtable.h | 5 ++++-
> arch/nios2/kernel/module.c | 19 ++++---------------
> 2 files changed, 8 insertions(+), 16 deletions(-)
>
> diff --git a/arch/nios2/include/asm/pgtable.h b/arch/nios2/include/asm/pgtable.h
> index 0f5c2564e9f5..0073b289c6a4 100644
> --- a/arch/nios2/include/asm/pgtable.h
> +++ b/arch/nios2/include/asm/pgtable.h
> @@ -25,7 +25,10 @@
> #include <asm-generic/pgtable-nopmd.h>
>
> #define VMALLOC_START CONFIG_NIOS2_KERNEL_MMU_REGION_BASE
> -#define VMALLOC_END (CONFIG_NIOS2_KERNEL_REGION_BASE - 1)
> +#define VMALLOC_END (CONFIG_NIOS2_KERNEL_REGION_BASE - SZ_32M - 1)
> +
> +#define MODULES_VADDR (CONFIG_NIOS2_KERNEL_REGION_BASE - SZ_32M)
> +#define MODULES_END (CONFIG_NIOS2_KERNEL_REGION_BASE - 1)
>
> struct mm_struct;
>
> diff --git a/arch/nios2/kernel/module.c b/arch/nios2/kernel/module.c
> index 76e0a42d6e36..9c97b7513853 100644
> --- a/arch/nios2/kernel/module.c
> +++ b/arch/nios2/kernel/module.c
> @@ -21,23 +21,12 @@
>
> #include <asm/cacheflush.h>
>
> -/*
> - * Modules should NOT be allocated with kmalloc for (obvious) reasons.
> - * But we do it for now to avoid relocation issues. CALL26/PCREL26 cannot reach
> - * from 0x80000000 (vmalloc area) to 0xc00000000 (kernel) (kmalloc returns
> - * addresses in 0xc0000000)
> - */
> void *module_alloc(unsigned long size)
> {
> - if (size == 0)
> - return NULL;
> - return kmalloc(size, GFP_KERNEL);
> -}
> -
> -/* Free memory returned from module_alloc */
> -void module_memfree(void *module_region)
> -{
> - kfree(module_region);
> + return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
> + GFP_KERNEL, PAGE_KERNEL_EXEC,
> + VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
> + __builtin_return_address(0));
> }
>
> int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
> --
> 2.35.1
>
On Fri, Jun 16, 2023 at 04:00:19PM +0000, Edgecombe, Rick P wrote:
> On Fri, 2023-06-16 at 11:50 +0300, Mike Rapoport wrote:
> > ?void *module_alloc(unsigned long size)
> > ?{
> > -???????if (size == 0)
> > -???????????????return NULL;
> > -???????return kmalloc(size, GFP_KERNEL);
> > -}
> > -
> > -/* Free memory returned from module_alloc */
> > -void module_memfree(void *module_region)
> > -{
> > -???????kfree(module_region);
> > +???????return __vmalloc_node_range(size, 1, MODULES_VADDR,
> > MODULES_END,
> > +?????????????????????????????????? GFP_KERNEL, PAGE_KERNEL_EXEC,
> > +?????????????????????????????????? VM_FLUSH_RESET_PERMS,
> > NUMA_NO_NODE,
> > +?????????????????????????????????? __builtin_return_address(0));
> > ?}
> > ?
> > ?int apply_relocate_add(Elf32_Shdr *sechdrs, const char *s
>
> I wonder if the (size == 0) check is really needed, but
> __vmalloc_node_range() will WARN on this case where the old code won't.
module_alloc() should not be called with zero size, so a warning there
would be appropriate.
Besides, no other module_alloc() had this check.
--
Sincerely yours,
Mike.