mirror of https://github.com/acidanthera/audk.git
ce13d2d8c8
The SPC-4 says about INQUIRY,
> In response to an INQUIRY command received by an incorrect logical unit,
> the SCSI target device shall return the INQUIRY data with the peripheral
> qualifier set to the value defined in 6.4.2. The INQUIRY command shall
> return CHECK CONDITION status only when the device server is unable to
> return the requested INQUIRY data.
When a device server takes the second branch, and returns CHECK CONDITION
for a nonexistent LUN, the InquiryData structure in the
DiscoverScsiDevice() function remains filled with the original zeros.
DiscoverScsiDevice() then sees zero in both Peripheral_Qualifier and
Peripheral_Type, and therefore ScsiBusDxe produces a ScsiIo protocol
instance with device type zero, for the nonexistent LUN.
Device type zero is EFI_SCSI_TYPE_DISK. Thus ScsiDiskDxe binds the bogus
ScsiIo protocol interface, and produces a similarly bogus BlockIo
interface on top. This ripples up to BDS, where UefiBootManagerLib can
auto-generate bogus UEFI boot options for the nonexistent LUNs.
This has been encountered with QEMU, after commit ded6ddc5a7b9 ("scsi:
clarify sense codes for LUN0 emulation", 2017-08-04). QEMU now answers
INQUIRY commands that were directed to nonexistent LUNs with:
> DiscoverScsiDevice:1361: Lun=2 HostAdapterStatus=0 TargetStatus=2
> SenseDataLength=18 InquiryDataLength=96
> Sense {
> Sense 000000 70 00 05 00 00 00 00 0A 00 00 00 00 25 00 00 00
> Sense 000010 00 00
> Sense }
> Inquiry {
> Inquiry 000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> Inquiry 000010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> Inquiry 000020 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> Inquiry 000030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> Inquiry 000040 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> Inquiry 000050 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> Inquiry }
The interesting fields are:
- HostAdapterStatus=0 (OK),
- TargetStatus=2 (CHECK CONDITION),
- Sense/Error_Code=0x70 (Current error, Fixed description)
- Sense/Sense_Key=0x05 (ILLEGAL REQUEST)
According to SPC-4 "Table 41 -- Sense key descriptions (part 2 of 2)",
ILLEGAL REQUEST is justified when "the command was addressed to an
incorrect logical unit number".
Thus, recognize this kind of answer for nonexistent LUNs.
(
Checking the status fields and the sense data is justified anyway,
according to the documentation of ScsiInquiryCommand():
> @retval EFI_SUCCESS The command was executed
> successfully. See
> HostAdapterStatus,
> TargetStatus, SenseDataLength,
> and SenseData in that order for
> additional status information.
)
Cc: Eric Dong <eric.dong@intel.com>
Cc: Feng Tian <feng.tian@intel.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
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