diff mbox

[PATCHv2,2/2] arm: Adjust memory boundaries after reservations

Message ID 1483657274-11346-3-git-send-email-labbott@redhat.com (mailing list archive)
State New, archived
Headers show

Commit Message

Laura Abbott Jan. 5, 2017, 11:01 p.m. UTC
adjust_lowmem_bounds is responsible for setting up the boundary for
lowmem/hihgmme. This needs to be setup before memblock reservations can
occur. At the time memblock reservations can occur, memory can also be
removed from the system. The lowmem/highmem boundary and end of memory
may be affected by this but it is currently not recalculated. On some
systems this may be harmless, on o thers this may result in incorrect
ranges being passed to the main memory allocator. Correct this by
recalculating the lowmem/highmem boundary after all reservations have
been made.

Signed-off-by: Laura Abbott <labbott@redhat.com>
---
v2: Rebased for changes in sanity_check_meminfo cleanup
---
 arch/arm/kernel/setup.c | 8 ++++++++
 arch/arm/mm/mmu.c       | 9 ++++++---
 2 files changed, 14 insertions(+), 3 deletions(-)

Comments

Russell King (Oracle) Jan. 6, 2017, 12:41 a.m. UTC | #1
Only comments are to do with the comments...

On Thu, Jan 05, 2017 at 03:01:14PM -0800, Laura Abbott wrote:
> 
> adjust_lowmem_bounds is responsible for setting up the boundary for
> lowmem/hihgmme. This needs to be setup before memblock reservations can

highmem

> occur. At the time memblock reservations can occur, memory can also be
> removed from the system. The lowmem/highmem boundary and end of memory
> may be affected by this but it is currently not recalculated. On some
> systems this may be harmless, on o thers this may result in incorrect

others

> ranges being passed to the main memory allocator. Correct this by
> recalculating the lowmem/highmem boundary after all reservations have
> been made.
> 
> Signed-off-by: Laura Abbott <labbott@redhat.com>
> ---
> v2: Rebased for changes in sanity_check_meminfo cleanup
> ---
>  arch/arm/kernel/setup.c | 8 ++++++++
>  arch/arm/mm/mmu.c       | 9 ++++++---
>  2 files changed, 14 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
> index 8a8051c..4625115 100644
> --- a/arch/arm/kernel/setup.c
> +++ b/arch/arm/kernel/setup.c
> @@ -1093,8 +1093,16 @@ void __init setup_arch(char **cmdline_p)
>  	setup_dma_zone(mdesc);
>  	xen_early_init();
>  	efi_init();
> +	/*
> +	 * Make sure the calcualtion for lowmem/highmem is set appropriately

calculation

> +	 * before reserving/allocating any mmeory
> +	 */
>  	adjust_lowmem_bounds();
>  	arm_memblock_init(mdesc);
> +	/*
> +	 * Memory may have been removed so recalculate the bounds.
> +	 */

Single line comments should be... /* blah */

> +	adjust_lowmem_bounds();
>  
>  	early_ioremap_reset();
>  
> diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
> index ce5123b..7ca6910 100644
> --- a/arch/arm/mm/mmu.c
> +++ b/arch/arm/mm/mmu.c
> @@ -1157,6 +1157,7 @@ void __init adjust_lowmem_bounds(void)
>  	phys_addr_t memblock_limit = 0;
>  	u64 vmalloc_limit;
>  	struct memblock_region *reg;
> +	phys_addr_t lowmem_limit = 0;
>  
>  	/*
>  	 * Let's use our own (unoptimized) equivalent of __pa() that is
> @@ -1173,14 +1174,14 @@ void __init adjust_lowmem_bounds(void)
>  
>  
>  		if (reg->base < vmalloc_limit) {
> -			if (block_end > arm_lowmem_limit)
> +			if (block_end > lowmem_limit)
>  				/*
>  				 * Compare as u64 to ensure vmalloc_limit does
>  				 * not get truncated. block_end should always
>  				 * fit in phys_addr_t so there should be no
>  				 * issue with assignment.
>  				 */
> -				arm_lowmem_limit = min_t(u64,
> +				lowmem_limit = min_t(u64,
>  							 vmalloc_limit,
>  							 block_end);
>  
> @@ -1201,12 +1202,14 @@ void __init adjust_lowmem_bounds(void)
>  				if (!IS_ALIGNED(block_start, PMD_SIZE))
>  					memblock_limit = block_start;
>  				else if (!IS_ALIGNED(block_end, PMD_SIZE))
> -					memblock_limit = arm_lowmem_limit;
> +					memblock_limit = lowmem_limit;
>  			}
>  
>  		}
>  	}
>  
> +	arm_lowmem_limit = lowmem_limit;
> +
>  	high_memory = __va(arm_lowmem_limit - 1) + 1;
>  
>  	/*
> -- 
> 2.7.4
>
diff mbox

Patch

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 8a8051c..4625115 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -1093,8 +1093,16 @@  void __init setup_arch(char **cmdline_p)
 	setup_dma_zone(mdesc);
 	xen_early_init();
 	efi_init();
+	/*
+	 * Make sure the calcualtion for lowmem/highmem is set appropriately
+	 * before reserving/allocating any mmeory
+	 */
 	adjust_lowmem_bounds();
 	arm_memblock_init(mdesc);
+	/*
+	 * Memory may have been removed so recalculate the bounds.
+	 */
+	adjust_lowmem_bounds();
 
 	early_ioremap_reset();
 
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index ce5123b..7ca6910 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -1157,6 +1157,7 @@  void __init adjust_lowmem_bounds(void)
 	phys_addr_t memblock_limit = 0;
 	u64 vmalloc_limit;
 	struct memblock_region *reg;
+	phys_addr_t lowmem_limit = 0;
 
 	/*
 	 * Let's use our own (unoptimized) equivalent of __pa() that is
@@ -1173,14 +1174,14 @@  void __init adjust_lowmem_bounds(void)
 
 
 		if (reg->base < vmalloc_limit) {
-			if (block_end > arm_lowmem_limit)
+			if (block_end > lowmem_limit)
 				/*
 				 * Compare as u64 to ensure vmalloc_limit does
 				 * not get truncated. block_end should always
 				 * fit in phys_addr_t so there should be no
 				 * issue with assignment.
 				 */
-				arm_lowmem_limit = min_t(u64,
+				lowmem_limit = min_t(u64,
 							 vmalloc_limit,
 							 block_end);
 
@@ -1201,12 +1202,14 @@  void __init adjust_lowmem_bounds(void)
 				if (!IS_ALIGNED(block_start, PMD_SIZE))
 					memblock_limit = block_start;
 				else if (!IS_ALIGNED(block_end, PMD_SIZE))
-					memblock_limit = arm_lowmem_limit;
+					memblock_limit = lowmem_limit;
 			}
 
 		}
 	}
 
+	arm_lowmem_limit = lowmem_limit;
+
 	high_memory = __va(arm_lowmem_limit - 1) + 1;
 
 	/*