linux-next: manual merge of the risc-v tree with the risc-v-fixes tree

  Hi all,

Today's linux-next merge of the risc-v tree got a conflict in:

  arch/riscv/mm/init.c

between commit:

  ef69d2559fe91 ("riscv: Move early dtb mapping into the fixmap region")

from the risc-v-fixes tree and commits:

  8589e346bbb67 ("riscv: Move the linear mapping creation in its own function")
  3335068f87217 ("riscv: Use PUD/P4D/PGD pages for the linear mapping")

from the risc-v tree.

I fixed it up (see below) and can carry the fix as necessary. This
is now fixed as far as linux-next is concerned, but any non trivial
conflicts should be mentioned to your upstream maintainer when your tree
is submitted for merging.  You may also want to consider cooperating
with the maintainer of the conflicting tree to minimise any particularly
complex conflicts.

+++ b/arch/riscv/mm/init.c
@@@ -1070,26 -1112,36 +1092,47 @@@ asmlinkage void __init setup_vm(uintptr
  	pt_ops_set_fixmap();
  }
  
- static void __init setup_vm_final(void)
+ static void __init create_linear_mapping_range(phys_addr_t start,
+ 					       phys_addr_t end)
  {
+ 	phys_addr_t pa;
  	uintptr_t va, map_size;
- 	phys_addr_t pa, start, end;
- 	u64 i;
  
- 	/* Setup swapper PGD for fixmap */
 +#if !defined(CONFIG_64BIT)
 +	/*
 +	 * In 32-bit, the device tree lies in a pgd entry, so it must be copied
 +	 * directly in swapper_pg_dir in addition to the pgd entry that points
 +	 * to fixmap_pte.
 +	 */
 +	unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT));
 +
 +	set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]);
 +#endif
- 	create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
- 			   __pa_symbol(fixmap_pgd_next),
- 			   PGDIR_SIZE, PAGE_TABLE);
++
+ 	for (pa = start; pa < end; pa += map_size) {
+ 		va = (uintptr_t)__va(pa);
+ 		map_size = best_map_size(pa, end - pa);
+ 
+ 		create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
+ 				   pgprot_from_va(va));
+ 	}
+ }
+ 
+ static void __init create_linear_mapping_page_table(void)
+ {
+ 	phys_addr_t start, end;
+ 	u64 i;
+ 
+ #ifdef CONFIG_STRICT_KERNEL_RWX
+ 	phys_addr_t ktext_start = __pa_symbol(_start);
+ 	phys_addr_t ktext_size = __init_data_begin - _start;
+ 	phys_addr_t krodata_start = __pa_symbol(__start_rodata);
+ 	phys_addr_t krodata_size = _data - __start_rodata;
+ 
+ 	/* Isolate kernel text and rodata so they don't get mapped with a PUD */
+ 	memblock_mark_nomap(ktext_start,  ktext_size);
+ 	memblock_mark_nomap(krodata_start, krodata_size);
+ #endif
  
  	/* Map all memory banks in the linear mapping */
  	for_each_mem_range(i, &start, &end) {
  

Hi,

On Thu, Apr 20, 2023 at 2:40 PM <broonie@kernel.org> wrote:
>
> Hi all,
>
> Today's linux-next merge of the risc-v tree got a conflict in:
>
>   arch/riscv/mm/init.c
>
> between commit:
>
>   ef69d2559fe91 ("riscv: Move early dtb mapping into the fixmap region")
>
> from the risc-v-fixes tree and commits:
>
>   8589e346bbb67 ("riscv: Move the linear mapping creation in its own function")
>   3335068f87217 ("riscv: Use PUD/P4D/PGD pages for the linear mapping")
>
> from the risc-v tree.
>
> I fixed it up (see below) and can carry the fix as necessary. This
> is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging.  You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.
>
> diff --cc arch/riscv/mm/init.c
> index 0f14f4a8d179a,7bd66795165da..0000000000000
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@@ -1070,26 -1112,36 +1092,47 @@@ asmlinkage void __init setup_vm(uintptr
>         pt_ops_set_fixmap();
>   }
>
> - static void __init setup_vm_final(void)
> + static void __init create_linear_mapping_range(phys_addr_t start,
> +                                              phys_addr_t end)
>   {
> +       phys_addr_t pa;
>         uintptr_t va, map_size;
> -       phys_addr_t pa, start, end;
> -       u64 i;
>
> -       /* Setup swapper PGD for fixmap */
>  +#if !defined(CONFIG_64BIT)
>  +      /*
>  +       * In 32-bit, the device tree lies in a pgd entry, so it must be copied
>  +       * directly in swapper_pg_dir in addition to the pgd entry that points
>  +       * to fixmap_pte.
>  +       */
>  +      unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT));
>  +
>  +      set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]);
>  +#endif

This does not look correct, fixmap setup should not be in
create_linear_mapping_range() function.
Please find below the diff I would apply:

diff --cc arch/riscv/mm/init.c
index 0f14f4a8d179,7bd66795165d..a19146ab9341
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@@ -1070,23 -1112,63 +1092,74 @@@ asmlinkage void __init setup_vm(uintptr
        pt_ops_set_fixmap();
  }

- static void __init setup_vm_final(void)
+ static void __init create_linear_mapping_range(phys_addr_t start,
+                                              phys_addr_t end)
  {
+       phys_addr_t pa;
        uintptr_t va, map_size;
-       phys_addr_t pa, start, end;
+
+       for (pa = start; pa < end; pa += map_size) {
+               va = (uintptr_t)__va(pa);
+               map_size = best_map_size(pa, end - pa);
+
+               create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
+                                  pgprot_from_va(va));
+       }
+ }
+
+ static void __init create_linear_mapping_page_table(void)
+ {
+       phys_addr_t start, end;
        u64 i;

+ #ifdef CONFIG_STRICT_KERNEL_RWX
+       phys_addr_t ktext_start = __pa_symbol(_start);
+       phys_addr_t ktext_size = __init_data_begin - _start;
+       phys_addr_t krodata_start = __pa_symbol(__start_rodata);
+       phys_addr_t krodata_size = _data - __start_rodata;
+
+       /* Isolate kernel text and rodata so they don't get mapped with a PUD */
+       memblock_mark_nomap(ktext_start,  ktext_size);
+       memblock_mark_nomap(krodata_start, krodata_size);
+ #endif
+
+       /* Map all memory banks in the linear mapping */
+       for_each_mem_range(i, &start, &end) {
+               if (start >= end)
+                       break;
+               if (start <= __pa(PAGE_OFFSET) &&
+                   __pa(PAGE_OFFSET) < end)
+                       start = __pa(PAGE_OFFSET);
+               if (end >= __pa(PAGE_OFFSET) + memory_limit)
+                       end = __pa(PAGE_OFFSET) + memory_limit;
+
+               create_linear_mapping_range(start, end);
+       }
+
+ #ifdef CONFIG_STRICT_KERNEL_RWX
+       create_linear_mapping_range(ktext_start, ktext_start + ktext_size);
+       create_linear_mapping_range(krodata_start,
+                                   krodata_start + krodata_size);
+
+       memblock_clear_nomap(ktext_start,  ktext_size);
+       memblock_clear_nomap(krodata_start, krodata_size);
+ #endif
+ }
+
+ static void __init setup_vm_final(void)
+ {
        /* Setup swapper PGD for fixmap */
 +#if !defined(CONFIG_64BIT)
 +      /*
 +       * In 32-bit, the device tree lies in a pgd entry, so it must be copied
 +       * directly in swapper_pg_dir in addition to the pgd entry that points
 +       * to fixmap_pte.
 +       */
 +      unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT));
 +
 +      set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]);
 +#endif
++
        create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
                           __pa_symbol(fixmap_pgd_next),
                           PGDIR_SIZE, PAGE_TABLE);

> -       create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
> -                          __pa_symbol(fixmap_pgd_next),
> -                          PGDIR_SIZE, PAGE_TABLE);
> ++
> +       for (pa = start; pa < end; pa += map_size) {
> +               va = (uintptr_t)__va(pa);
> +               map_size = best_map_size(pa, end - pa);
> +
> +               create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
> +                                  pgprot_from_va(va));
> +       }
> + }
> +
> + static void __init create_linear_mapping_page_table(void)
> + {
> +       phys_addr_t start, end;
> +       u64 i;
> +
> + #ifdef CONFIG_STRICT_KERNEL_RWX
> +       phys_addr_t ktext_start = __pa_symbol(_start);
> +       phys_addr_t ktext_size = __init_data_begin - _start;
> +       phys_addr_t krodata_start = __pa_symbol(__start_rodata);
> +       phys_addr_t krodata_size = _data - __start_rodata;
> +
> +       /* Isolate kernel text and rodata so they don't get mapped with a PUD */
> +       memblock_mark_nomap(ktext_start,  ktext_size);
> +       memblock_mark_nomap(krodata_start, krodata_size);
> + #endif
>
>         /* Map all memory banks in the linear mapping */
>         for_each_mem_range(i, &start, &end) {

Thanks!

Alex
  

On Thu, Apr 20, 2023 at 03:23:55PM +0200, Alexandre Ghiti wrote:

> This does not look correct, fixmap setup should not be in
> create_linear_mapping_range() function.
> Please find below the diff I would apply:

OK, if it's opportune (basically doesn't require redoing huge amounts of
work) I'll replace the merge with your suggestion but I'm not sure if
that'll happen or not.  Probably best to highlight when sending the pull
request to Linus.
  

On Thu, Apr 20, 2023 at 03:23:55PM +0200, Alexandre Ghiti wrote:

> This does not look correct, fixmap setup should not be in
> create_linear_mapping_range() function.
> Please find below the diff I would apply:

There's actually another conflict in the riscv tree come up today so
I'll roll this in.