At 09/04/2017 05:39 PM, Igor Mammedov wrote:
On Thu, 31 Aug 2017 20:04:26 +0800
Dou Liyang <douly.f...@cn.fujitsu.com> wrote:
From: Eduardo Habkost <ehabk...@redhat.com>
Currently, Using the fisrt node without memory on the machine makes
QEMU unhappy. With this example command line:
... \
-m 1024M,slots=4,maxmem=32G \
-numa node,nodeid=0 \
-numa node,mem=1024M,nodeid=1 \
-numa node,nodeid=2 \
-numa node,nodeid=3 \
Guest reports "No NUMA configuration found" and the NUMA topology is
wrong.
This is because when QEMU builds ACPI SRAT, it regards node 0 as the
default node to deal with the memory hole(640K-1M). this means the
node0 must have some memory(>1M), but, actually it can have no
memory.
Fix this problem by cut out the 640K hole in the same way the PCI
4G hole does. Also do some cleanup.
Signed-off-by: Eduardo Habkost <ehabk...@redhat.com>
Signed-off-by: Dou Liyang <douly.f...@cn.fujitsu.com>
---
hw/i386/acpi-build.c | 30 +++++++++++++++++++++++-------
1 file changed, 23 insertions(+), 7 deletions(-)
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 98dd424..48525a1 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -2318,6 +2318,9 @@ build_tpm2(GArray *table_data, BIOSLinker *linker)
(void *)tpm2_ptr, "TPM2", sizeof(*tpm2_ptr), 4, NULL, NULL);
}
+#define HOLE_640K_START (640 * 1024)
+#define HOLE_640K_END (1024 * 1024)
+
static void
build_srat(GArray *table_data, BIOSLinker *linker, MachineState *machine)
{
@@ -2373,17 +2376,30 @@ build_srat(GArray *table_data, BIOSLinker *linker,
MachineState *machine)
next_base = 0;
numa_start = table_data->len;
- numamem = acpi_data_push(table_data, sizeof *numamem);
- build_srat_memory(numamem, 0, 640 * 1024, 0, MEM_AFFINITY_ENABLED);
- next_base = 1024 * 1024;
for (i = 1; i < pcms->numa_nodes + 1; ++i) {
mem_base = next_base;
mem_len = pcms->node_mem[i - 1];
- if (i == 1) {
- mem_len -= 1024 * 1024;
- }
next_base = mem_base + mem_len;
+ /* Cut out the 640K hole */
+ if (mem_base <= HOLE_640K_START &&
+ next_base > HOLE_640K_START) {
+ mem_len -= next_base - HOLE_640K_START;
+ if (mem_len > 0) {
+ numamem = acpi_data_push(table_data, sizeof *numamem);
+ build_srat_memory(numamem, mem_base, mem_len, i - 1,
+ MEM_AFFINITY_ENABLED);
+ }
+
+ /* Check for the rare case: 640K < RAM < 1M */
+ if (next_base <= HOLE_640K_END) {
+ next_base = HOLE_640K_END;
Is this assignment really necessary?
It is necessary, because we set mem_base to next_base before setting
next_base;
But, I can refine it:
MEM_AFFINITY_ENABLED);
}
+ mem_base = HOLE_640K_END;
/* Check for the rare case: 640K < RAM < 1M */
if (next_base <= HOLE_640K_END) {
- next_base = HOLE_640K_END;
continue;
}
- mem_base = HOLE_640K_END;
mem_len = next_base - HOLE_640K_END;
}
Is it?
Thanks,
dou.
it seems that next_base will be set at the start of the loop.
+ continue;
+ }
+ mem_base = HOLE_640K_END;
+ mem_len = next_base - HOLE_640K_END;
+ }
+
/* Cut out the ACPI_PCI hole */
if (mem_base <= pcms->below_4g_mem_size &&
next_base > pcms->below_4g_mem_size) {
@@ -2395,7 +2411,7 @@ build_srat(GArray *table_data, BIOSLinker *linker,
MachineState *machine)
}
mem_base = 1ULL << 32;
mem_len = next_base - pcms->below_4g_mem_size;
- next_base += (1ULL << 32) - pcms->below_4g_mem_size;
+ next_base = mem_base + mem_len;
}
numamem = acpi_data_push(table_data, sizeof *numamem);
build_srat_memory(numamem, mem_base, mem_len, i - 1,
