My Laptop has an SD card slot. If there is no card in the slot, the syslog repeatedly, every 50 seconds or so, records messages like: May 1 11:40:41 dellie-linux kernel: [ 8793.621511] sd 6:0:0:0: [sdb] Test WP failed, assume Write Enabled May 1 11:40:41 dellie-linux kernel: [ 8793.623878] sd 6:0:0:0: [sdb] Asking for cache data failed May 1 11:40:41 dellie-linux kernel: [ 8793.623886] sd 6:0:0:0: [sdb] Assuming drive cache: write through May 1 11:41:33 dellie-linux kernel: [ 8845.337522] sd 6:0:0:0: [sdb] Test WP failed, assume Write Enabled May 1 11:41:33 dellie-linux kernel: [ 8845.339930] sd 6:0:0:0: [sdb] Asking for cache data failed May 1 11:41:33 dellie-linux kernel: [ 8845.339939] sd 6:0:0:0: [sdb] Assuming drive cache: write through Additional info: Linux version 3.4.0-030400rc4-generic (apw@gomeisa) (gcc version 4.4.3 (Ubuntu 4.4.3-4ubuntu5.1) ) #201204230908 SMP Mon Apr 23 13:10:03 UTC 2012
Created attachment 73146 [details] cpu info
Created attachment 73147 [details] modules
Created attachment 73148 [details] ioports
Created attachment 73149 [details] iomem
Created attachment 73150 [details] lspci
Created attachment 73151 [details] scsi
Thanks for the report -- this SD controller is presenting itself as a SCSI device, and these messages are coming from the SCSI layer. So, the MMC stack isn't involved, and you should report this to the Linux SCSI maintainers, please. It looks like the linux-scsi@vger.kernel.org is a good way to do that: mailing lists tend to get read more than Bugzilla, in my experience.
*** This bug has been marked as a duplicate of bug 43191 ***