[BUG] bind command leads to invalid state where plaform data is NULL

[Simon Glass]

Hi Heinrich,

On Sun, 18 Jun 2023 at 11:12, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
> Hello Simon,
>
> from origin/next I build qemu_arm64_defconfig with CONFIG_CMD_BIND=yes.
>
> I ran the image with:
>
> qemu-system-aarch64 -semihosting \
>      -machine virt,gic-version=max -accel $(ACCEL) -m 1G -smp cores=2 \
>      -bios u-boot.bin -cpu $(CPU) -nographic -gdb tcp::1234 \
>      -netdev user,id=eth0,tftp=tftp -device e1000,netdev=eth0,romfile= \
>      -drive if=none,file=arm64.img,format=raw,id=mydisk \
>      -drive if=pflash,format=raw,index=1,file=envstore.img \
>      -device virtio-rng-pci \
>      -device ich9-ahci,id=ahci -device ide-hd,drive=mydisk,bus=ahci.0
>
> => scsi bind
> => dm tree
>   Class     Index  Probed  Driver                Name
> -----------------------------------------------------------
>   root          0  [ + ]   root_driver           root_driver
>   pci           0  [ + ]   pci_generic_ecam      |-- pcie at 10000000
>   pci_generi    0  [   ]   pci_generic_drv       |   |-- pci_0:0.0
>   ahci          0  [ + ]   ahci_pci              |   `-- ahci_pci
>   scsi          0  [ + ]   ahci_scsi             |       `-- ahci_scsi
>   blk           0  [ + ]   scsi_blk              |           |--
> ahci_scsi.id0lun0
>   partition     0  [ + ]   blk_partition         |           |   |--
> ahci_scsi.id0lun0:1
>   partition     1  [ + ]   blk_partition         |           |   `--
> ahci_scsi.id0lun0:15
>   bootdev       2  [   ]   scsi_bootdev          |           `--
> ahci_scsi.id0lun0.bootdev
> => unbind blk 0
> => dm tree
>   Class     Index  Probed  Driver                Name
> -----------------------------------------------------------
>   root          0  [ + ]   root_driver           root_driver
>   pci           0  [ + ]   pci_generic_ecam      |-- pcie at 10000000
>   pci_generi    0  [   ]   pci_generic_drv       |   |-- pci_0:0.0
>   ahci          0  [ + ]   ahci_pci              |   `-- ahci_pci
>   scsi          0  [ + ]   ahci_scsi             |       `-- ahci_scsi
>   bootdev       2  [   ]   scsi_bootdev          |           `--
> ahci_scsi.id0lun0.bootdev
> => bind scsi 0 scsi_blk
> => dm tree
>   Class     Index  Probed  Driver                Name
> -----------------------------------------------------------
>   root          0  [ + ]   root_driver           root_driver
>   pci           0  [ + ]   pci_generic_ecam      |-- pcie at 10000000
>   pci_generi    0  [   ]   pci_generic_drv       |   |-- pci_0:0.0
>   ahci          0  [ + ]   ahci_pci              |   `-- ahci_pci
>   scsi          0  [ + ]   ahci_scsi             |       `-- ahci_scsi
>   bootdev       2  [   ]   scsi_bootdev          |           |--
> ahci_scsi.id0lun0.bootdev
>   blk           0  [   ]   scsi_blk              |           `-- scsi_blk
> => part list scsi 0
> dev_get_uclass_plat: null device
> "Synchronous Abort" handler, esr 0x96000004, far 0xd503201f14000072
> elr: 000000000003392c lr : 0000000000033924 (reloc)
> elr: 000000007ff1492c lr : 000000007ff14924
> x0 : d503201f1400000a x1 : 0000000000000000
> x2 : 0000000000000090 x3 : 0000000000000013
> x4 : 000000007eda0419 x5 : 0000000000000020
> x6 : 00000000ffffffd0 x7 : 000000007eda06b0
> x8 : 0000000000000010 x9 : 0000000000000000
> x10: 0000000000000006 x11: 000000000001869f
> x12: 0000000000000016 x13: 0000000000000004
> x14: 0000000000000000 x15: 000000007eda073c
> x16: 000000007ff2547c x17: 0000000000000000
> x18: 000000007eea0db0 x19: 0000000000000000
> x20: 0000000000000000 x21: 0000000000000001
> x22: 0000000000000000 x23: 000000007eda0740
> x24: 0000000000000000 x25: 0000000000000000
> x26: 0000000000000000 x27: 0000000000000000
> x28: 0000000000000000 x29: 000000007eda06d0
>
> Code: aa0303f7 94000287 aa0003f4 f9400260 (f9403418)
> Resetting CPU ...
>
> The crash occurs in blk_read(). blk_read() does not check if desc == NULL.
>
> I would have expected "bind scsi 0 scsi_blk" to create a valid state
> where the platform data is set up.
>
> Best regards
>
> Heinrich

I am not sure what 'scsi bind' does.

But binding a blk device needs to be done by its parent device. I
suspect the 'bind' command does not know how to set up things
correctly. See for example blk_create_device() which does quite a lot
of setup.

What are you trying to fix / do?

Regards,
Simon