From 5bd9d9a509dabe5e1f151e2b85c863c6c71a819f Mon Sep 17 00:00:00 2001 Message-Id: <5bd9d9a509dabe5e1f151e2b85c863c6c71a819f.1351776104.git.minovotn@redhat.com> In-Reply-To: <383c464e74b19af5a4e1e18bb56df969e9d61c2a.1351776104.git.minovotn@redhat.com> References: <383c464e74b19af5a4e1e18bb56df969e9d61c2a.1351776104.git.minovotn@redhat.com> From: Eduardo Habkost Date: Mon, 29 Oct 2012 18:52:32 +0100 Subject: [PATCH 06/11] pc: set fw_cfg data based on APIC ID calculation RH-Author: Eduardo Habkost Message-id: <1351536756-16475-7-git-send-email-ehabkost@redhat.com> Patchwork-id: 43758 O-Subject: [RHEL6.4 qemu-kvm PATCH 06/10] pc: set fw_cfg data based on APIC ID calculation Bugzilla: 733720 RH-Acked-by: Laszlo Ersek RH-Acked-by: Igor Mammedov RH-Acked-by: Gleb Natapov Bugzilla: 733720 Related TestOnly BZs: 816804, 815958, 782648 Upstream status: submitted Message-Id: <1351101001-14589-24-git-send-email-ehabkost@redhat.com> http://article.gmane.org/gmane.comp.emulators.qemu/177664 This changes FW_CFG_MAX_CPUS and FW_CFG_NUMA to use apic_id_for_cpu(), so the NUMA table can be based on the APIC IDs, instead of CPU index (SeaBIOS knows nothing about CPU indexes, just APIC IDs). Signed-off-by: Eduardo Habkost --- hw/pc.c | 41 ++++++++++++++++++++++++++++++++++------- 1 file changed, 34 insertions(+), 7 deletions(-) Signed-off-by: Michal Novotny --- hw/pc.c | 41 ++++++++++++++++++++++++++++++++++------- 1 file changed, 34 insertions(+), 7 deletions(-) diff --git a/hw/pc.c b/hw/pc.c index 0e7dee0..2a4022f 100644 --- a/hw/pc.c +++ b/hw/pc.c @@ -470,6 +470,15 @@ uint32_t apic_id_for_cpu(int cpu_index) return cpu_index; } +/* Returns the limit to APIC ID values + * + * This is used for FW_CFG_MAX_CPUS. See comments on bochs_bios_init(). + */ +static unsigned int apic_id_limit(void) +{ + return apic_id_for_cpu(max_cpus - 1) + 1; +} + static void *bochs_bios_init(void) { void *fw_cfg; @@ -477,6 +486,7 @@ static void *bochs_bios_init(void) size_t smbios_len; uint64_t *numa_fw_cfg; int i, j; + unsigned int max_apic_id = apic_id_limit(); register_ioport_write(0x400, 1, 2, bochs_bios_write, NULL); register_ioport_write(0x401, 1, 2, bochs_bios_write, NULL); @@ -490,7 +500,21 @@ static void *bochs_bios_init(void) register_ioport_write(0x503, 1, 1, bochs_bios_write, NULL); fw_cfg = fw_cfg_init(BIOS_CFG_IOPORT, BIOS_CFG_IOPORT + 1, 0, 0); - fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, (uint16_t)max_cpus); + /* FW_CFG_MAX_CPUS is a bit confusing/problematic on x86: + * + * SeaBIOS needs FW_CFG_MAX_CPUS for CPU hotplug, but the CPU hotplug + * QEMU<->SeaBIOS interface is not based on the "CPU index", but on the APIC + * ID of hotplugged CPUs[1]. This means that FW_CFG_MAX_CPUS is not the + * "maximum number of CPUs", but the "limit to the APIC ID values SeaBIOS + * may see". + * + * So, this means we must not use max_cpus, here, but the maximum possible + * APIC ID value, plus one. + * + * [1] The only kind of "CPU identifier" used between SeaBIOS and QEMU is + * the APIC ID, not the "CPU index" + */ + fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, (uint16_t)max_apic_id); fw_cfg_add_i32(fw_cfg, FW_CFG_ID, 1); fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, (uint64_t)ram_size); fw_cfg_add_bytes(fw_cfg, FW_CFG_ACPI_TABLES, (uint8_t *)acpi_tables, @@ -506,21 +530,24 @@ static void *bochs_bios_init(void) * of nodes, one word for each VCPU->node and one word for each node to * hold the amount of memory. */ - numa_fw_cfg = qemu_mallocz((1 + smp_cpus + nb_numa_nodes) * 8); + numa_fw_cfg = g_malloc0((1 + max_apic_id + nb_numa_nodes) * 8); numa_fw_cfg[0] = cpu_to_le64(nb_numa_nodes); - for (i = 0; i < smp_cpus; i++) { + unsigned int cpu_idx; + for (cpu_idx = 0; cpu_idx < max_cpus; cpu_idx++) { + unsigned int apic_id = apic_id_for_cpu(cpu_idx); + assert(apic_id < max_apic_id); for (j = 0; j < nb_numa_nodes; j++) { - if (test_bit(i, node_cpumask[j])) { - numa_fw_cfg[i + 1] = cpu_to_le64(j); + if (test_bit(cpu_idx, node_cpumask[j])) { + numa_fw_cfg[apic_id + 1] = cpu_to_le64(j); break; } } } for (i = 0; i < nb_numa_nodes; i++) { - numa_fw_cfg[smp_cpus + 1 + i] = cpu_to_le64(node_mem[i]); + numa_fw_cfg[max_apic_id + 1 + i] = cpu_to_le64(node_mem[i]); } fw_cfg_add_bytes(fw_cfg, FW_CFG_NUMA, (uint8_t *)numa_fw_cfg, - (1 + smp_cpus + nb_numa_nodes) * 8); + (1 + max_apic_id + nb_numa_nodes) * 8); return fw_cfg; } -- 1.7.11.7