[PATCH 1/2] Revert "x86/e820: put !E820_TYPE_RAM regions into memblock.reserved"

From: Masayoshi Mizuma
Date: Thu Aug 23 2018 - 14:25:36 EST


From: Masayoshi Mizuma <m.mizuma@xxxxxxxxxxxxxx>

commit 124049decbb1 ("x86/e820: put !E820_TYPE_RAM regions into
memblock.reserved") breaks movable_node kernel option because it
changed the memory gap range to reserved memblock. So, the node
is marked as Normal zone even if the SRAT has Hot plaggable affinity.

=====================================================================
kernel: BIOS-e820: [mem 0x0000180000000000-0x0000180fffffffff] usable
kernel: BIOS-e820: [mem 0x00001c0000000000-0x00001c0fffffffff] usable
...
kernel: reserved[0x12]#011[0x0000181000000000-0x00001bffffffffff], 0x000003f000000000 bytes flags: 0x0
...
kernel: ACPI: SRAT: Node 2 PXM 6 [mem 0x180000000000-0x1bffffffffff] hotplug
kernel: ACPI: SRAT: Node 3 PXM 7 [mem 0x1c0000000000-0x1fffffffffff] hotplug
...
kernel: Movable zone start for each node
kernel: Node 3: 0x00001c0000000000
kernel: Early memory node ranges
...
=====================================================================

Naoya's v1 patch [*] fixes the original issue and this movable_node
issue doesn't occur.
Let's revert commit 124049decbb1 ("x86/e820: put !E820_TYPE_RAM
regions into memblock.reserved") and apply the v1 patch.

[*] https://lkml.org/lkml/2018/6/13/27

Signed-off-by: Masayoshi Mizuma <m.mizuma@xxxxxxxxxxxxxx>
---
arch/x86/kernel/e820.c | 15 +++------------
1 file changed, 3 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index c88c23c658c1..d1f25c831447 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -1248,7 +1248,6 @@ void __init e820__memblock_setup(void)
{
int i;
u64 end;
- u64 addr = 0;

/*
* The bootstrap memblock region count maximum is 128 entries
@@ -1265,21 +1264,13 @@ void __init e820__memblock_setup(void)
struct e820_entry *entry = &e820_table->entries[i];

end = entry->addr + entry->size;
- if (addr < entry->addr)
- memblock_reserve(addr, entry->addr - addr);
- addr = end;
if (end != (resource_size_t)end)
continue;

- /*
- * all !E820_TYPE_RAM ranges (including gap ranges) are put
- * into memblock.reserved to make sure that struct pages in
- * such regions are not left uninitialized after bootup.
- */
if (entry->type != E820_TYPE_RAM && entry->type != E820_TYPE_RESERVED_KERN)
- memblock_reserve(entry->addr, entry->size);
- else
- memblock_add(entry->addr, entry->size);
+ continue;
+
+ memblock_add(entry->addr, entry->size);
}

/* Throw away partial pages: */
--
2.18.0