[PATCH] ARM: NOMMU: Fix conversion for_each_membock() to for_each_mem_range()

[Mike Rapoport]

On Wed, Mar 10, 2021 at 10:20:13AM +0000, Vladimir Murzin wrote:
> for_each_mem_range() uses a loop variable, yet looking into code it is
> not just iteration counter but more complex entity which encodes
> information about memblock. Thus condition i == 0 looks fragile.
> Indeed, it broke boot of R-class platforms since it never took i == 0
> path (due to i was set to 1).

Oops, sorry about that.

> Fix that with restoring original flag
> check.
> 
> Fixes: b10d6bca8720 ("arch, drivers: replace for_each_membock() with for_each_mem_range()")
> Signed-off-by: Vladimir Murzin <vladimir.murzin at arm.com>

Acked-by: Mike Rapoport <rppt at linux.ibm.com>

> ---
>  arch/arm/mm/pmsa-v7.c | 4 +++-
>  arch/arm/mm/pmsa-v8.c | 4 +++-
>  2 files changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/mm/pmsa-v7.c b/arch/arm/mm/pmsa-v7.c
> index 88950e41a3a9..59d916ccdf25 100644
> --- a/arch/arm/mm/pmsa-v7.c
> +++ b/arch/arm/mm/pmsa-v7.c
> @@ -235,6 +235,7 @@ void __init pmsav7_adjust_lowmem_bounds(void)
>  	phys_addr_t mem_end;
>  	phys_addr_t reg_start, reg_end;
>  	unsigned int mem_max_regions;
> +	bool first = true;
>  	int num;
>  	u64 i;
>  
> @@ -263,7 +264,7 @@ void __init pmsav7_adjust_lowmem_bounds(void)
>  #endif
>  
>  	for_each_mem_range(i, &reg_start, &reg_end) {
> -		if (i == 0) {
> +		if (first) {
>  			phys_addr_t phys_offset = PHYS_OFFSET;
>  
>  			/*
> @@ -275,6 +276,7 @@ void __init pmsav7_adjust_lowmem_bounds(void)
>  			mem_start = reg_start;
>  			mem_end = reg_end;
>  			specified_mem_size = mem_end - mem_start;
> +			first = false;
>  		} else {
>  			/*
>  			 * memblock auto merges contiguous blocks, remove
> diff --git a/arch/arm/mm/pmsa-v8.c b/arch/arm/mm/pmsa-v8.c
> index 2de019f7503e..8359748a19a1 100644
> --- a/arch/arm/mm/pmsa-v8.c
> +++ b/arch/arm/mm/pmsa-v8.c
> @@ -95,10 +95,11 @@ void __init pmsav8_adjust_lowmem_bounds(void)
>  {
>  	phys_addr_t mem_end;
>  	phys_addr_t reg_start, reg_end;
> +	bool first = true;
>  	u64 i;
>  
>  	for_each_mem_range(i, &reg_start, &reg_end) {
> -		if (i == 0) {
> +		if (first) {
>  			phys_addr_t phys_offset = PHYS_OFFSET;
>  
>  			/*
> @@ -107,6 +108,7 @@ void __init pmsav8_adjust_lowmem_bounds(void)
>  			if (reg_start != phys_offset)
>  				panic("First memory bank must be contiguous from PHYS_OFFSET");
>  			mem_end = reg_end;
> +			first = false;
>  		} else {
>  			/*
>  			 * memblock auto merges contiguous blocks, remove
> -- 
> 2.24.0
> 

-- 
Sincerely yours,
Mike.