On Mon, 4 Sep 2017 18:16:31 +0800 Dou Liyang <douly.f...@cn.fujitsu.com> wrote:
> 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? I was wrong, so just leave it as it is now. > > 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, > > > > > > > > > >