Any sub-page size update to ACPI table MRs will be lost during migration, as we use aligned size in ram_load_precopy() -> qemu_ram_resize() path. This will result in inconsistency in sizes between source and destination. In order to avoid this, save and restore them separately during migration.
Suggested-by: David Hildenbrand <[email protected]> Signed-off-by: Shameer Kolothum <[email protected]> --- Please find the discussion here, https://patchwork.kernel.org/patch/11339591/ --- hw/core/machine.c | 1 + hw/nvram/fw_cfg.c | 86 ++++++++++++++++++++++++++++++++++++++- include/hw/nvram/fw_cfg.h | 6 +++ 3 files changed, 92 insertions(+), 1 deletion(-) diff --git a/hw/core/machine.c b/hw/core/machine.c index 9e8c06036f..6d960bd47f 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -39,6 +39,7 @@ GlobalProperty hw_compat_4_2[] = { { "usb-redir", "suppress-remote-wake", "off" }, { "qxl", "revision", "4" }, { "qxl-vga", "revision", "4" }, + { "fw_cfg", "acpi-mr-restore", "false" }, }; const size_t hw_compat_4_2_len = G_N_ELEMENTS(hw_compat_4_2); diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c index 179b302f01..36d1e32f83 100644 --- a/hw/nvram/fw_cfg.c +++ b/hw/nvram/fw_cfg.c @@ -39,6 +39,7 @@ #include "qemu/config-file.h" #include "qemu/cutils.h" #include "qapi/error.h" +#include "hw/acpi/aml-build.h" #define FW_CFG_FILE_SLOTS_DFLT 0x20 @@ -610,6 +611,50 @@ bool fw_cfg_dma_enabled(void *opaque) return s->dma_enabled; } +static bool fw_cfg_acpi_mr_restore(void *opaque) +{ + FWCfgState *s = opaque; + return s->acpi_mr_restore; +} + +static void fw_cfg_update_mr(FWCfgState *s, uint16_t key, size_t size) +{ + MemoryRegion *mr; + ram_addr_t offset; + int arch = !!(key & FW_CFG_ARCH_LOCAL); + void *ptr; + + key &= FW_CFG_ENTRY_MASK; + assert(key < fw_cfg_max_entry(s)); + + ptr = s->entries[arch][key].data; + mr = memory_region_from_host(ptr, &offset); + + memory_region_ram_resize(mr, size, &error_abort); +} + +static int fw_cfg_acpi_mr_restore_post_load(void *opaque, int version_id) +{ + FWCfgState *s = opaque; + int i, index; + + assert(s->files); + + index = be32_to_cpu(s->files->count); + + for (i = 0; i < index; i++) { + if (!strcmp(s->files->f[i].name, ACPI_BUILD_TABLE_FILE)) { + fw_cfg_update_mr(s, FW_CFG_FILE_FIRST + i, s->table_mr_size); + } else if (!strcmp(s->files->f[i].name, ACPI_BUILD_LOADER_FILE)) { + fw_cfg_update_mr(s, FW_CFG_FILE_FIRST + i, s->linker_mr_size); + } else if (!strcmp(s->files->f[i].name, ACPI_BUILD_RSDP_FILE)) { + fw_cfg_update_mr(s, FW_CFG_FILE_FIRST + i, s->rsdp_mr_size); + } + } + + return 0; +} + static const VMStateDescription vmstate_fw_cfg_dma = { .name = "fw_cfg/dma", .needed = fw_cfg_dma_enabled, @@ -619,6 +664,20 @@ static const VMStateDescription vmstate_fw_cfg_dma = { }, }; +static const VMStateDescription vmstate_fw_cfg_acpi_mr = { + .name = "fw_cfg/acpi_mr", + .version_id = 1, + .minimum_version_id = 1, + .needed = fw_cfg_acpi_mr_restore, + .post_load = fw_cfg_acpi_mr_restore_post_load, + .fields = (VMStateField[]) { + VMSTATE_UINT64(table_mr_size, FWCfgState), + VMSTATE_UINT64(linker_mr_size, FWCfgState), + VMSTATE_UINT64(rsdp_mr_size, FWCfgState), + VMSTATE_END_OF_LIST() + }, +}; + static const VMStateDescription vmstate_fw_cfg = { .name = "fw_cfg", .version_id = 2, @@ -631,6 +690,7 @@ static const VMStateDescription vmstate_fw_cfg = { }, .subsections = (const VMStateDescription*[]) { &vmstate_fw_cfg_dma, + &vmstate_fw_cfg_acpi_mr, NULL, } }; @@ -815,6 +875,23 @@ static struct { #define FW_CFG_ORDER_OVERRIDE_LAST 200 }; +/* + * Any sub-page size update to these table MRs will be lost during migration, + * as we use aligned size in ram_load_precopy() -> qemu_ram_resize() path. + * In order to avoid the inconsistency in sizes save them seperately and + * migrate over in vmstate post_load(). + */ +static void fw_cfg_acpi_mr_save(FWCfgState *s, const char *filename, size_t len) +{ + if (!strcmp(filename, ACPI_BUILD_TABLE_FILE)) { + s->table_mr_size = len; + } else if (!strcmp(filename, ACPI_BUILD_LOADER_FILE)) { + s->linker_mr_size = len; + } else if (!strcmp(filename, ACPI_BUILD_RSDP_FILE)) { + s->rsdp_mr_size = len; + } +} + static int get_fw_cfg_order(FWCfgState *s, const char *name) { int i; @@ -914,6 +991,7 @@ void fw_cfg_add_file_callback(FWCfgState *s, const char *filename, trace_fw_cfg_add_file(s, index, s->files->f[index].name, len); s->files->count = cpu_to_be32(count+1); + fw_cfg_acpi_mr_save(s, filename, len); } void fw_cfg_add_file(FWCfgState *s, const char *filename, @@ -937,6 +1015,7 @@ void *fw_cfg_modify_file(FWCfgState *s, const char *filename, ptr = fw_cfg_modify_bytes_read(s, FW_CFG_FILE_FIRST + i, data, len); s->files->f[i].size = cpu_to_be32(len); + fw_cfg_acpi_mr_save(s, filename, len); return ptr; } } @@ -973,7 +1052,10 @@ static void fw_cfg_machine_ready(struct Notifier *n, void *data) qemu_register_reset(fw_cfg_machine_reset, s); } - +static Property fw_cfg_properties[] = { + DEFINE_PROP_BOOL("acpi-mr-restore", FWCfgState, acpi_mr_restore, true), + DEFINE_PROP_END_OF_LIST(), +}; static void fw_cfg_common_realize(DeviceState *dev, Error **errp) { @@ -1097,6 +1179,8 @@ static void fw_cfg_class_init(ObjectClass *klass, void *data) dc->reset = fw_cfg_reset; dc->vmsd = &vmstate_fw_cfg; + + device_class_set_props(dc, fw_cfg_properties); } static const TypeInfo fw_cfg_info = { diff --git a/include/hw/nvram/fw_cfg.h b/include/hw/nvram/fw_cfg.h index b5291eefad..457fee7425 100644 --- a/include/hw/nvram/fw_cfg.h +++ b/include/hw/nvram/fw_cfg.h @@ -53,6 +53,12 @@ struct FWCfgState { dma_addr_t dma_addr; AddressSpace *dma_as; MemoryRegion dma_iomem; + + /* restore during migration */ + bool acpi_mr_restore; + size_t table_mr_size; + size_t linker_mr_size; + size_t rsdp_mr_size; }; struct FWCfgIoState { -- 2.17.1
