mirror of https://gitee.com/openkylin/qemu.git
e12f3a13e2
We'd like to raise the value of FW_CFG_FILE_SLOTS. Doing it naively could lead to problems with backward migration: a more recent QEMU (running an older machine type) would allow the guest, in fw_cfg_select(), to select a high key value that is unavailable in the same machine type implemented by the older (target) QEMU. On the target host, fw_cfg_data_read() for example could dereference nonexistent entries. As first step, size the FWCfgState.entries[*] and FWCfgState.entry_order arrays dynamically. All three array sizes will be influenced by the new field FWCfgState.file_slots (and matching device property). Make the following changes: - Replace the FW_CFG_FILE_SLOTS macro with FW_CFG_FILE_SLOTS_MIN (minimum count of fw_cfg file slots) in the header file. The value remains 0x10. - Replace all uses of FW_CFG_FILE_SLOTS with a helper function called fw_cfg_file_slots(), returning the new property. - Eliminate the macro FW_CFG_MAX_ENTRY, and replace all its uses with a helper function called fw_cfg_max_entry(). - In the MMIO- and IO-mapped realize functions both, allocate all three arrays dynamically, based on the new property. - The new property defaults to FW_CFG_FILE_SLOTS_MIN. This is going to be customized in the following patches. Cc: "Gabriel L. Somlo" <somlo@cmu.edu> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Gerd Hoffmann <kraxel@redhat.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Laszlo Ersek <lersek@redhat.com> Acked-by: Gabriel Somlo <somlo@cmu.edu> Tested-by: Gabriel Somlo <somlo@cmu.edu> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com> |
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| .. | ||
| chrp_nvram.h | ||
| eeprom93xx.h | ||
| fw_cfg.h | ||
| fw_cfg_keys.h | ||
| sun_nvram.h | ||