2021-07-28 07:17:17

by Kenneth Lee

Subject: [PATCH v2] riscv: fix the global name pfn_base confliction error

From: Kenneth Lee <[email protected]>

RISCV uses a global variable pfn_base for page/pfn translation. But this
is a common name and will be used elsewhere. In those cases, the
page-pfn macros which refer to this name will be referred to the
local/input variable instead. (such as in vfio_pin_pages_remote). This
make everything wrong.

This patch changes the name from pfn_base to riscv_pfn_base to fix
this problem

Chagne from V1:
use riscv_pfn_base instead of riscv_global_pfn_base.

Signed-off-by: Kenneth Lee <[email protected]>
---
arch/riscv/include/asm/page.h | 4 ++--
arch/riscv/mm/init.c | 6 +++---
2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h
index cca8764aed83..c690e83bde23 100644
--- a/arch/riscv/include/asm/page.h
+++ b/arch/riscv/include/asm/page.h
@@ -79,8 +79,8 @@ typedef struct page *pgtable_t;
#endif

#ifdef CONFIG_MMU
-extern unsigned long pfn_base;
-#define ARCH_PFN_OFFSET (pfn_base)
+extern unsigned long riscv_pfn_base;
+#define ARCH_PFN_OFFSET (riscv_pfn_base)
#else
#define ARCH_PFN_OFFSET (PAGE_OFFSET >> PAGE_SHIFT)
#endif /* CONFIG_MMU */
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index a14bf3910eec..788f12bb586b 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -228,8 +228,8 @@ static struct pt_alloc_ops _pt_ops __initdata;
#define pt_ops _pt_ops
#endif

-unsigned long pfn_base __ro_after_init;
-EXPORT_SYMBOL(pfn_base);
+unsigned long riscv_pfn_base __ro_after_init;
+EXPORT_SYMBOL(riscv_pfn_base);

pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
@@ -572,7 +572,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr;
#endif

- pfn_base = PFN_DOWN(kernel_map.phys_addr);
+ riscv_pfn_base = PFN_DOWN(kernel_map.phys_addr);

/*
* Enforce boot alignment requirements of RV32 and
--
2.25.1

2021-08-14 05:11:31

by Palmer Dabbelt

Subject: Re: [PATCH v2] riscv: fix the global name pfn_base confliction error

On Wed, 28 Jul 2021 00:15:57 PDT (-0700), [email protected] wrote:
> From: Kenneth Lee <[email protected]>
>
> RISCV uses a global variable pfn_base for page/pfn translation. But this
> is a common name and will be used elsewhere. In those cases, the
> page-pfn macros which refer to this name will be referred to the
> local/input variable instead. (such as in vfio_pin_pages_remote). This
> make everything wrong.
>
> This patch changes the name from pfn_base to riscv_pfn_base to fix
> this problem
>
> Chagne from V1:
> use riscv_pfn_base instead of riscv_global_pfn_base.
>
> Signed-off-by: Kenneth Lee <[email protected]>
> ---
> arch/riscv/include/asm/page.h | 4 ++--
> arch/riscv/mm/init.c | 6 +++---
> 2 files changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h
> index cca8764aed83..c690e83bde23 100644
> --- a/arch/riscv/include/asm/page.h
> +++ b/arch/riscv/include/asm/page.h
> @@ -79,8 +79,8 @@ typedef struct page *pgtable_t;
> #endif
>
> #ifdef CONFIG_MMU
> -extern unsigned long pfn_base;
> -#define ARCH_PFN_OFFSET (pfn_base)
> +extern unsigned long riscv_pfn_base;
> +#define ARCH_PFN_OFFSET (riscv_pfn_base)
> #else
> #define ARCH_PFN_OFFSET (PAGE_OFFSET >> PAGE_SHIFT)
> #endif /* CONFIG_MMU */
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index a14bf3910eec..788f12bb586b 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -228,8 +228,8 @@ static struct pt_alloc_ops _pt_ops __initdata;
> #define pt_ops _pt_ops
> #endif
>
> -unsigned long pfn_base __ro_after_init;
> -EXPORT_SYMBOL(pfn_base);
> +unsigned long riscv_pfn_base __ro_after_init;
> +EXPORT_SYMBOL(riscv_pfn_base);
>
> pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
> pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
> @@ -572,7 +572,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
> kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr;
> #endif
>
> - pfn_base = PFN_DOWN(kernel_map.phys_addr);
> + riscv_pfn_base = PFN_DOWN(kernel_map.phys_addr);
>
> /*
> * Enforce boot alignment requirements of RV32 and

Thanks, this is on for-next.