When booting up windows VM which converted by dd scsi disk, it fails with "Error Loading Operating System", root cause is rombios doesn''t simulate disk''s logical CHS properly. Real bios uses spt=32 here. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> --- a/tools/firmware/rombios/rombios.c 2011-12-09 00:50:28.000000000 +0800 +++ b/tools/firmware/rombios/rombios.c 2012-11-20 09:42:50.000000000 +0800 @@ -2674,6 +2674,8 @@ void ata_detect( ) Bit32u sectors_low, sectors_high; Bit16u cylinders, heads, spt, blksize; Bit8u translation, removable, mode; + Bit8u i; + Bit8u *p; // default mode to PIO16 mode = ATA_MODE_PIO16; @@ -2738,14 +2740,32 @@ void ata_detect( ) case ATA_TRANSLATION_NONE: break; case ATA_TRANSLATION_LBA: - spt = 63; - sectors_low /= 63; - heads = sectors_low / 1024; - if (heads>128) heads = 255; - else if (heads>64) heads = 128; - else if (heads>32) heads = 64; - else if (heads>16) heads = 32; - else heads=16; + spt = heads = 0; + if (ata_cmd_data_in(device,ATA_CMD_READ_SECTORS, 1, 0, 0, 1, 0L, 0L, get_SS(),buffer) !=0 ) + BX_PANIC("ata-detect: Failed to read first sector\n"); + for(i=0; i<4; i++) { + p = buffer + 0x1be + i * 16; + if (read_dword(get_SS(), p+12) && read_byte(get_SS(), p+5)) { + /* We make the assumption that the partition terminates on + a cylinder boundary */ + heads = read_byte(get_SS(), p+5) + 1; + spt = read_byte(get_SS(), p+6) & 63; + if (spt != 0) + break; + } + } + if (spt == 32) { + sectors_low /= spt; + } else { + spt = 63; + sectors_low /= 63; + heads = sectors_low / 1024; + if (heads>128) heads = 255; + else if (heads>64) heads = 128; + else if (heads>32) heads = 64; + else if (heads>16) heads = 32; + else heads=16; + } cylinders = sectors_low / heads; break; case ATA_TRANSLATION_RECHS:
Jan Beulich
2012-Dec-07 11:27 UTC
Re: rombios: add support for special CHS layout (spt=32)
>>> On 07.12.12 at 04:25, DuanZhenzhong <zhenzhong.duan@oracle.com> wrote: > When booting up windows VM which converted by dd scsi disk, it fails with > "Error Loading Operating System", root cause is rombios doesn''t simulate > disk''s > logical CHS properly. Real bios uses spt=32 here. > > Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> > --- a/tools/firmware/rombios/rombios.c 2011-12-09 00:50:28.000000000 +0800 > +++ b/tools/firmware/rombios/rombios.c 2012-11-20 09:42:50.000000000 +0800 > @@ -2674,6 +2674,8 @@ void ata_detect( ) > Bit32u sectors_low, sectors_high; > Bit16u cylinders, heads, spt, blksize; > Bit8u translation, removable, mode; > + Bit8u i; > + Bit8u *p; > > // default mode to PIO16 > mode = ATA_MODE_PIO16; > @@ -2738,14 +2740,32 @@ void ata_detect( ) > case ATA_TRANSLATION_NONE: > break; > case ATA_TRANSLATION_LBA: > - spt = 63; > - sectors_low /= 63; > - heads = sectors_low / 1024; > - if (heads>128) heads = 255; > - else if (heads>64) heads = 128; > - else if (heads>32) heads = 64; > - else if (heads>16) heads = 32; > - else heads=16; > + spt = heads = 0; > + if (ata_cmd_data_in(device,ATA_CMD_READ_SECTORS, 1, 0, 0, 1, 0L, 0L, get_SS(),buffer) !=0 ) > + BX_PANIC("ata-detect: Failed to read first sector\n"); > + for(i=0; i<4; i++) { > + p = buffer + 0x1be + i * 16; > + if (read_dword(get_SS(), p+12) && read_byte(get_SS(), p+5)) { > + /* We make the assumption that the partition terminates on > + a cylinder boundary */Which certainly isn''t a generally correct assumption, so I strongly recommend against basing any decisions on that. Jan> + heads = read_byte(get_SS(), p+5) + 1; > + spt = read_byte(get_SS(), p+6) & 63; > + if (spt != 0) > + break; > + } > + } > + if (spt == 32) { > + sectors_low /= spt; > + } else { > + spt = 63; > + sectors_low /= 63; > + heads = sectors_low / 1024; > + if (heads>128) heads = 255; > + else if (heads>64) heads = 128; > + else if (heads>32) heads = 64; > + else if (heads>16) heads = 32; > + else heads=16; > + } > cylinders = sectors_low / heads; > break; > case ATA_TRANSLATION_RECHS: > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel
Zhenzhong Duan
2012-Dec-10 02:15 UTC
Re: rombios: add support for special CHS layout (spt=32)
On 2012-12-07 19:27, Jan Beulich wrote:>>>> On 07.12.12 at 04:25, DuanZhenzhong <zhenzhong.duan@oracle.com> wrote: >> When booting up windows VM which converted by dd scsi disk, it fails with >> "Error Loading Operating System", root cause is rombios doesn''t simulate >> disk''s >> logical CHS properly. Real bios uses spt=32 here. >> >> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> >> --- a/tools/firmware/rombios/rombios.c 2011-12-09 00:50:28.000000000 +0800 >> +++ b/tools/firmware/rombios/rombios.c 2012-11-20 09:42:50.000000000 +0800 >> @@ -2674,6 +2674,8 @@ void ata_detect( ) >> Bit32u sectors_low, sectors_high; >> Bit16u cylinders, heads, spt, blksize; >> Bit8u translation, removable, mode; >> + Bit8u i; >> + Bit8u *p; >> >> // default mode to PIO16 >> mode = ATA_MODE_PIO16; >> @@ -2738,14 +2740,32 @@ void ata_detect( ) >> case ATA_TRANSLATION_NONE: >> break; >> case ATA_TRANSLATION_LBA: >> - spt = 63; >> - sectors_low /= 63; >> - heads = sectors_low / 1024; >> - if (heads>128) heads = 255; >> - else if (heads>64) heads = 128; >> - else if (heads>32) heads = 64; >> - else if (heads>16) heads = 32; >> - else heads=16; >> + spt = heads = 0; >> + if (ata_cmd_data_in(device,ATA_CMD_READ_SECTORS, 1, 0, 0, 1, 0L, 0L, get_SS(),buffer) !=0 ) >> + BX_PANIC("ata-detect: Failed to read first sector\n"); >> + for(i=0; i<4; i++) { >> + p = buffer + 0x1be + i * 16; >> + if (read_dword(get_SS(), p+12) && read_byte(get_SS(), p+5)) { >> + /* We make the assumption that the partition terminates on >> + a cylinder boundary */ > Which certainly isn''t a generally correct assumption, so I strongly > recommend against basing any decisions on that. > > JanThanks for comment. Are we the first facing this bug? Is there any workaround for this issue? zduan