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"blk_update_request: I/O error" when formatting eMMC
Added by V J about 4 years ago
Hi
In our system (rocko branch with kernel 4.9 RT ) we are using a Greenliant eMMC (https://www.greenliant.com/products/?inode=51976). This device is connected to the SOM as an SD-card, i.e. we use a 4 bit data interface. The device is quite new on the marked. When formatting this device (mke2fs) we get a couple of these error messages (e.g.):
blk_update_request: I/O error, dev mmcblk0, sector 2048
Despite the messages, the eMMC seems to be working correctly.
When testing with another eMMC from Micron and various SD-cards we do not get these I/O errors.
When connecting the eMMC (using an evaluation board) to a CentOS 7 laptop we do not see these I/O error messages.
So, we suspect there might be a driver/device tree issues? Any advice on this one?
BR
VJ
Replies (2)
RE: "blk_update_request: I/O error" when formatting eMMC - Added by Michael Williamson about 4 years ago
Hi VJ,
What version of the kernel was the CentOS 7 laptop using? Was the evaluation board presenting an MMC interface to the laptop, or was it hiding it behind a USB interface?
You might check with Greenliant and ask them if there is a specific version of the kernel their part is qualified for.
Are different sectors reported when you see the errors?
Thanks.
-Mike
RE: "blk_update_request: I/O error" when formatting eMMC - Added by V J about 4 years ago
Hi Mike,
thanks for the quick reply.
CentOS 7 laptop is using kernel: 3.10.0-957.5.1.el7.x86_64 #1 SMP Fri Feb 1 14:54:57 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
The evaluation board was connected using an external USB SD-card reader.
When formatting a partition, there is always an I/O error on the first sector , and the next following I/O error has always a sector offset of 32768. (2^15). This offset is found independent of partitioning of the device. When formatting a large partition there will be a few more I/O error messages.
BR
VJ
