Current calculation of max_low_pfn is introduced in commit af84eab20891
("[PATCH] uml: fix LVM crash"). It is intended to set max_low_pfn to the
same value as max_pfn.
But I am not sure why the max_pfn is set to totalram_pages, which
represents the number of usable pages in system instead of an absolute
page frame number. (The change history stops there.)
While we have already calculate it in setup_physmem(), so not necessary
to do it again.
Also this would help changing totalram_pages accounting, since we plan
to move the accounting into __free_pages_core(). With this change,
totalram_pages may not represent the total usable pages at this point,
since some pages would be deferred initialized.
Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
CC: Jeff Dike <jdike@xxxxxxxxxxxxxxx>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@xxxxxxxx>
Cc: Alasdair G Kergon <agk@xxxxxxxxxx>
CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
CC: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
CC: David Hildenbrand <david@xxxxxxxxxx>
---
v2: remove redundant assignment of max_low_pfn
---
arch/um/kernel/mem.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index ca91accd64fc..a5b4fe2ad931 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -73,7 +73,6 @@ void __init mem_init(void)
/* this will put all low memory onto the freelists */
memblock_free_all();
- max_low_pfn = totalram_pages();
max_pfn = max_low_pfn;
kmalloc_ok = 1;
}
--
2.34.1
