Can't mount my sdcard rw
I tried to format /sdcard/ via the recovery, but it would do nothing, contrary to what it logs.

So finally i've formatted it via newfs_msdos (/system/ needs to be mounted, the command is located at /system/bin/newfs_msdos ) :

/system/bin # ./newfs_msdos -F 32 /dev/block/mmcblk0p1
./newfs_msdos: warning, /dev/block/mmcblk0p1 is not a character device
./newfs_msdos: Skipping mount checks
/dev/block/mmcblk0p1: 5992960 sectors in 93640 FAT32 clusters (32768 bytes/cluster)
bps=512 spc=64 res=32 nft=2 mid=0xf0 spt=16 hds=4 hid=0 bsec=5994496 bspf=732 rdcl=2 infs=1 bkbs=2
/system/bin # ./newfs_msdos -F 32 /dev/block/mmcblk0p1
./newfs_msdos: warning, /dev/block/mmcblk0p1 is not a character device
./newfs_msdos: Skipping mount checks
/dev/block/mmcblk0p1: 5992960 sectors in 93640 FAT32 clusters (32768 bytes/cluster)
bps=512 spc=64 res=32 nft=2 mid=0xf0 spt=16 hds=4 hid=0 bsec=5994496 bspf=732 rdcl=2 infs=1 bkbs=2


and then my sdcard was fine, I could write on it and use it via USB. I guess it was somewhat corrupted.