diff mbox series

mm/memory_hotplug: Drop memblock_phys_free() call in try_remove_memory()

Message ID 20240605082049.973242-1-rppt@kernel.org (mailing list archive)
State New
Headers show
Series mm/memory_hotplug: Drop memblock_phys_free() call in try_remove_memory() | expand

Commit Message

Mike Rapoport June 5, 2024, 8:20 a.m. UTC
From: Jonathan Cameron <Jonathan.Cameron@huawei.com>

The call for memblock_phys_free() in try_remove_memory() does not balance
any call to memblock_alloc() (or memblock_reserve() for that matter).

There are no memblock_reserve() calls in mm/memory_hotplug.c, no memblock
allocations possible after mm_core_init(), and even if memblock_add_node()
called from add_memory_resource() would need to allocate memory, that
memory would ba allocated from slab.

The patch f9126ab9241f ("memory-hotplug: fix wrong edge when hot add a new
node") that introduced that call to memblock_free() does not provide
adequate description why that was required and tinkering with memblock in
the context of memory hotplug on x86 seems bogus because x86 never kept
memblock after boot anyway.

Drop memblock_phys_free() call in try_remove_memory().

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
[rppt: rewrite the commit message]
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
---
 mm/memory_hotplug.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

Comments

Oscar Salvador June 7, 2024, 7:37 a.m. UTC | #1
On Wed, Jun 05, 2024 at 11:20:49AM +0300, Mike Rapoport wrote:
> From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> 
> The call for memblock_phys_free() in try_remove_memory() does not balance
> any call to memblock_alloc() (or memblock_reserve() for that matter).
> 
> There are no memblock_reserve() calls in mm/memory_hotplug.c, no memblock
> allocations possible after mm_core_init(), and even if memblock_add_node()
> called from add_memory_resource() would need to allocate memory, that
> memory would ba allocated from slab.
> 
> The patch f9126ab9241f ("memory-hotplug: fix wrong edge when hot add a new
> node") that introduced that call to memblock_free() does not provide
> adequate description why that was required and tinkering with memblock in
> the context of memory hotplug on x86 seems bogus because x86 never kept
> memblock after boot anyway.
> 
> Drop memblock_phys_free() call in try_remove_memory().
> 
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> [rppt: rewrite the commit message]
> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>

Acked-by: Oscar Salvador <osalvador@suse.de>
Oscar Salvador June 10, 2024, 4:56 a.m. UTC | #2
On Wed, Jun 05, 2024 at 11:20:49AM +0300, Mike Rapoport wrote:
> From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> 
> The call for memblock_phys_free() in try_remove_memory() does not balance
> any call to memblock_alloc() (or memblock_reserve() for that matter).
> 
> There are no memblock_reserve() calls in mm/memory_hotplug.c, no memblock
> allocations possible after mm_core_init(), and even if memblock_add_node()
> called from add_memory_resource() would need to allocate memory, that
> memory would ba allocated from slab.
> 
> The patch f9126ab9241f ("memory-hotplug: fix wrong edge when hot add a new
> node") that introduced that call to memblock_free() does not provide
> adequate description why that was required and tinkering with memblock in
> the context of memory hotplug on x86 seems bogus because x86 never kept
> memblock after boot anyway.
> 
> Drop memblock_phys_free() call in try_remove_memory().
> 
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> [rppt: rewrite the commit message]
> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>

Acked-by: Oscar Salvador <osalvador@suse.de>

> ---
>  mm/memory_hotplug.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> index 431b1f6753c0..e0d49f128e0d 100644
> --- a/mm/memory_hotplug.c
> +++ b/mm/memory_hotplug.c
> @@ -2283,10 +2283,8 @@ static int __ref try_remove_memory(u64 start, u64 size)
>  		remove_memory_blocks_and_altmaps(start, size);
>  	}
>  
> -	if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) {
> -		memblock_phys_free(start, size);
> +	if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK))
>  		memblock_remove(start, size);
> -	}
>  
>  	release_mem_region_adjustable(start, size);
>  
> -- 
> 2.43.0
>
diff mbox series

Patch

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 431b1f6753c0..e0d49f128e0d 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -2283,10 +2283,8 @@  static int __ref try_remove_memory(u64 start, u64 size)
 		remove_memory_blocks_and_altmaps(start, size);
 	}
 
-	if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) {
-		memblock_phys_free(start, size);
+	if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK))
 		memblock_remove(start, size);
-	}
 
 	release_mem_region_adjustable(start, size);