Subject: linux-next: manual merge of the akpm-current tree with the risc-v tree

From: Stephen Rothwell <[email-masked]>
Date: Tue, 6 Oct 2020 21:39:06 +1100

Hi all,

Today's linux-next merge of the akpm-current tree got a conflict in:

  arch/riscv/mm/init.c

between commit:

  c29c38fa2a8b ("RISC-V: Remove any memblock representing unusable memory area")

from the risc-v tree and commits:

  3520eeb79142 ("arch, drivers: replace for_each_membock() with for_each_mem_range()")

from the akpm-current 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.

It also looks like there is a bug in that risc-v tree patch: mem_start
is used uninitialised in setup_bootmem().
-- 
Cheers,
Stephen Rothwell

diff --cc arch/riscv/mm/init.c
index 812a48c91a95,bc72bb6b5fe0..000000000000
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@@ -152,20 -141,25 +152,20 @@@ disable
  }
  #endif /* CONFIG_BLK_DEV_INITRD */
  
 -static phys_addr_t dtb_early_pa __initdata;
 -
  void __init setup_bootmem(void)
  {
- 	struct memblock_region *reg;
- 	phys_addr_t mem_start, end = 0;
 -	phys_addr_t mem_size = 0;
 -	phys_addr_t total_mem = 0;
+ 	phys_addr_t mem_start, start, end = 0;
  	phys_addr_t vmlinux_end = __pa_symbol(&_end);
  	phys_addr_t vmlinux_start = __pa_symbol(&_start);
+ 	u64 i;
  
  	/* Find the memory region containing the kernel */
- 	for_each_memblock(memory, reg) {
- 		end = reg->base + reg->size;
+ 	for_each_mem_range(i, &start, &end) {
+ 		phys_addr_t size = end - start;
 -		if (!total_mem)
 +		if (!mem_start)
- 			mem_start = reg->base;
- 		if (reg->base <= vmlinux_start && vmlinux_end <= end)
- 			BUG_ON(reg->size == 0);
+ 			mem_start = start;
+ 		if (start <= vmlinux_start && vmlinux_end <= end)
+ 			BUG_ON(size == 0);
 -		total_mem = total_mem + size;
  	}
  
  	/*
@@@ -542,18 -455,11 +533,18 @@@ static void __init setup_vm_final(void
  {
  	uintptr_t va, map_size;
  	phys_addr_t pa, start, end;
- 	struct memblock_region *reg;
+ 	u64 i;
  
 -	/* Set mmu_enabled flag */
 -	mmu_enabled = true;
 -
 +	/**
 +	 * MMU is enabled at this point. But page table setup is not complete yet.
 +	 * fixmap page table alloc functions should be used at this point
 +	 */
 +	pt_ops.alloc_pte = alloc_pte_fixmap;
 +	pt_ops.get_pte_virt = get_pte_virt_fixmap;
 +#ifndef __PAGETABLE_PMD_FOLDED
 +	pt_ops.alloc_pmd = alloc_pmd_fixmap;
 +	pt_ops.get_pmd_virt = get_pmd_virt_fixmap;
 +#endif
  	/* Setup swapper PGD for fixmap */
  	create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
  			   __pa_symbol(fixmap_pgd_next),