On Wed, 29 Jun 2011, Peter Rasmussen wrote: > Alan> Did you notice this response from the "mount" program? > > > root@kultorvet:/home/plr# mount /dev/sda1 /mnt/usb > > mount: wrong fs type, bad option, bad superblock on /dev/sda1, > > missing codepage or helper program, or other error > > In some cases useful info is found in syslog - try > > dmesg | tail or so > > Peter> Yes, I have seen it many times in the past and never really found it > useful, thus not paying much attention to it. In this case, the "missing codepage" is what gave me the clue. > Alan> first glance it appears that your 3.0-rc4 kernel configuration is > Alan> missing something. Did you forget to build in support for VFAT > Alan> (CONFIG_VFAT_FS) or the appropriate codepage (CONFIG_NLS_ASCII and > Alan> CONFIG_NLS_CODEPAGE_437)? > > Peter> Thanks a lot, now I got tracking on something! CONFIG_VFAT_FS is set, but > CONFIG_NLS_ASCII and CONFIG_NLS_CODEPAGE_437 wasn't set in my 3.0rc4 kernel. > Peter> When executing "mkfs.ext2 /dev/sda1" I could mount it, and after > rebuilding 3.0rc4 with those flags set, I can now also mount it with a FAT32 FS > on. > Peter> I didn't actually _forget_ to set the two _NLS_ flags, as I had never > made the connection unless you had mentioned it. Being from Denmark I prefer > table 865 and sometimes I have set the tables 865 and/or 850, without paying > much attention as it isn't something I have ever seen as an issue, until now. > Peter> I am however, from the 'old school' and most often build my kernels as > lean as possible, with everything that I need built in and nothing else, so they > were most often unset and not just for example set to be built as modules. > Peter> As config files sometimes changes after an update I don't always get > everything adjusted, and an ASCII or a 437 may sometimes have slipped in. Perhaps you could omit the 437 codepage if you change the setting of CONFIG_FAT_DEFAULT_CODEPAGE. I don't know what the ASCII gets used for -- maybe it's not necessary. > Peter> A better (=more precise) error message when attempting to mount a volume > would be great, There's a limited communication channel for errors between the kernel and userspace, and error codes sometimes are necessarily imprecise. > Peter> I am very glad that this first issue seems to be cleared, I learned > something, and I will continue with the next issue that I mentioned in the first > post, ie. other adapters behaving differently with the same flash card and the > same kernel. > Peter> I do hope it is more exciting than being some silly CONFIG flag. Probably. To start with, let's see the dmesg log and a usbmon trace showing what happens when you plug in one of those other adapters with the SDHC card present. You can continue to use 3.0-rc4, and make sure that CONFIG_USB_DEBUG is enabled. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
