On Wed, Mar 11, 2020 at 05:20:06PM +0000, Shameer Kolothum wrote: > 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 <da...@redhat.com> > Signed-off-by: Shameer Kolothum <shameerali.kolothum.th...@huawei.com>
Is there a reason this is part of nvdimm patchset? > --- > 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 >
