diff options
| author | Sam Eiderman <shmuel.eiderman@oracle.com> | 2019-10-16 19:41:44 +0300 |
|---|---|---|
| committer | John Snow <jsnow@redhat.com> | 2019-10-31 11:47:38 -0400 |
| commit | aea60a13b9d43bb4c5748a1216af954a0e9d22d4 (patch) | |
| tree | 8b8a8e2439331639633636a48136604f9dc65720 /hw/nvram | |
| parent | 42f068019926078e8cd61c7c4357143199003f0b (diff) | |
bootdevice: FW_CFG interface for LCHS values
Using fw_cfg, supply logical CHS values directly from QEMU to the BIOS.
Non-standard logical geometries break under QEMU.
A virtual disk which contains an operating system which depends on
logical geometries (consistent values being reported from BIOS INT13
AH=08) will most likely break under QEMU/SeaBIOS if it has non-standard
logical geometries - for example 56 SPT (sectors per track).
No matter what QEMU will report - SeaBIOS, for large enough disks - will
use LBA translation, which will report 63 SPT instead.
In addition we cannot force SeaBIOS to rely on physical geometries at
all. A virtio-blk-pci virtual disk with 255 phyiscal heads cannot
report more than 16 physical heads when moved to an IDE controller,
since the ATA spec allows a maximum of 16 heads - this is an artifact of
virtualization.
By supplying the logical geometries directly we are able to support such
"exotic" disks.
We serialize this information in a similar way to the "bootorder"
interface.
The new fw_cfg entry is "bios-geometry".
Reviewed-by: Karl Heubaum <karl.heubaum@oracle.com>
Reviewed-by: Arbel Moshe <arbel.moshe@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Sam Eiderman <shmuel.eiderman@oracle.com>
Signed-off-by: Sam Eiderman <sameid@google.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Diffstat (limited to 'hw/nvram')
| -rw-r--r-- | hw/nvram/fw_cfg.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c index aef1727250..44a3c19326 100644 --- a/hw/nvram/fw_cfg.c +++ b/hw/nvram/fw_cfg.c @@ -949,13 +949,21 @@ void *fw_cfg_modify_file(FWCfgState *s, const char *filename, static void fw_cfg_machine_reset(void *opaque) { + MachineClass *mc = MACHINE_GET_CLASS(qdev_get_machine()); + FWCfgState *s = opaque; void *ptr; size_t len; - FWCfgState *s = opaque; - char *bootindex = get_boot_devices_list(&len); + char *buf; - ptr = fw_cfg_modify_file(s, "bootorder", (uint8_t *)bootindex, len); + buf = get_boot_devices_list(&len); + ptr = fw_cfg_modify_file(s, "bootorder", (uint8_t *)buf, len); g_free(ptr); + + if (!mc->legacy_fw_cfg_order) { + buf = get_boot_devices_lchs_list(&len); + ptr = fw_cfg_modify_file(s, "bios-geometry", (uint8_t *)buf, len); + g_free(ptr); + } } static void fw_cfg_machine_ready(struct Notifier *n, void *data) |