Installer ISO stuck in stage1 when booted from (micro) SD card

[andir]

Describe the bug
When an installer image is copied onto a SD card and booted on hardware supporting boot from SD cards (e.g. my XP13 9380) the boot loader loads fine, the stage1 boot starts but fails to find the root device (the SD card). It seems that we are just missing drivers for those devices within the initramfs / stage1.

To Reproduce
Steps to reproduce the behavior:

1. create an ISO installer from master
2. copy / dd it to a (micro) SD card
3. boot from the SD card
4. stage1 fails to find the root device.
5. launch the interactive shell and verify that /dev/mmcblkX isn't present.

Expected behavior
We should be able to boot x86_64-linux installer from SD cards. Many devices support booting from them and it is a nice alternative to USB sticks (mostly because they disappear into their slot and you do not have to care about them much).

Additional context
Add any other context about the problem here.

Metadata

• system: "x86_64-linux"
• host os: Linux 5.2.10, NixOS, 19.09pre190978.8d1510abfb5 (Loris)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.3pre6779_324a5dc9
• channels(root): "nixos-19.09pre190978.8d1510abfb5"
• channels(andi): "home-manager"
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos

Maintainer information:

# a list of nixpkgs attributes affected by the problem
attribute:
# a list of nixos modules affected by the problem
module:
  probably some of the installer profiles. I am not sure what is the best place to add the module. Also not sure what the entire landscape of drivers requried for most current systems is.

[dasJ]

Can you run 19.09 on the device and check the module in use with lsusb?
You can then verify if it was loaded by inspecting /proc/modules (I doubt there is lsmod in the initrd) on 19.09 when booting with boot.debug1devices

[andir]

As far as I can tell it must be this PCIe device:

01:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS525A PCI Express Card Reader (rev 01)
	Subsystem: Dell Device 08af
	Flags: bus master, fast devsel, latency 0, IRQ 131
	Memory at 9c400000 (32-bit, non-prefetchable) [size=4K]
	Capabilities: [80] Power Management version 3
	Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit+
	Capabilities: [b0] Express Endpoint, MSI 00
	Capabilities: [100] Advanced Error Reporting
	Capabilities: [148] Device Serial Number 00-00-00-01-00-4c-e0-00
	Capabilities: [158] Latency Tolerance Reporting
	Capabilities: [160] L1 PM Substates
	Kernel driver in use: rtsx_pci
	Kernel modules: rtsx_pci

And these are the potential modules:

# lsmod | grep mmc
mmc_block              45056  0
rtsx_pci_sdmmc         32768  0
mmc_core              155648  2 rtsx_pci_sdmmc,mmc_block
rtsx_pci               69632  2 rtsx_pci_sdmmc,rtsx_pci_ms

(from a running 19.09 system)

I can still back to the installer on the SD card and get details some time in the next days.

[lheckemann]

Considering this not-a-blocker since it's not a regression of something that worked before and not a very common use case. That said, I'd absolutely be for backporting this to 19.09 when fixed.

[stale]

Thank you for your contributions.
This has been automatically marked as stale because it has had no activity for 180 days.
If this is still important to you, we ask that you leave a comment below. Your comment can be as simple as "still important to me". This lets people see that at least one person still cares about this. Someone will have to do this at most twice a year if there is no other activity.
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[andir]

A classical example where the stalebot just adds noise. This issue is still relevant and needs to be tackled. It is just a matter of priorities. We could close it but that would not do anything about the issue...

[stale]

I marked this as stale due to inactivity. → More info