Micro SD card not working on 4.8.3 (Slate AX / GL-AXT1800)

[ibern]

Upgraded from 4.6.x to 4.8.3. The micro SD card is no longer detected — no /dev/mmcblk devices, no kernel messages about card insertion. The SDHCI controller is initialized (mmc0: SDHCI controller on 7804000.sdhci_sd using ADMA 64-bit) and the card-detect GPIO is wired (Got CD GPIO) but the card never shows up regardless of reinsertion or driver rebinds.
This appears to be the same regression reported in the 4.8.2 thread (66083) which GL.iNet acknowledged as a kernel version compatibility issue. It persists in 4.8.3. Reverting to 4.6.11 resolves it immediately (as confirmed in the original report).

• Device: GL-AXT1800 (Slate AX)
• Firmware: v4.8.3, kernel 5.4.164
• Card: 32 GB formatted as vfat
• fstab mount config present but card never appears at kernel level
• dmesg shows no mmcblk device, no capacity detection, no partition scan
• Unbind/rebind of sdhci_msm driver doesn't help

[will.qiu]

Hi

We are still investigating this issue, although progress has been slower than expected.

Could you please help us with the following?

1. What is the brand, model, and capacity of the SD card that is experiencing the issue?

2. Could you please follow the guide and share your device with us via GoodCloud so that we can investigate it remotely?
   Technical Support via GoodCloud - GL.iNet Router Docs 4

   Kindly send us the router's MAC address and password via private message so that we can access the device.