Created attachment 78261 [details] my kernel config First to say, this happens with 3.5.2 kernel too. After upgrade to 3.5.1 mount of my 200G+ partition started taking a lot of time, here's `strace -tt mount -a` with 3.5.1 kernel: 15:45:26.074958 mount("/dev/sda3", "/mnt/2", "ext4", MS_MGC_VAL|MS_NOATIME, "errors=remount-ro,data=journal") = 0 15:45:34.940793 access("/mnt/2", W_OK) = 0 and with 3.5.0 with same config: 15:09:33.408747 mount("/dev/sda3", "/mnt/2", "ext4", MS_MGC_VAL|MS_NOATIME, "errors=remount-ro,data=journal") = 0 15:09:33.578511 access("/mnt/2", W_OK) = 0 First I thought it was corruption on fs, but fsck -f -v and even formatting doesn't fix that. And, seems that small partition (4G), where my / is, still mounts fast.
Created attachment 78271 [details] dumpe2fs -h report of this partition
Created attachment 78281 [details] dmesg of kernel on which bug happens
Created attachment 78291 [details] smartctl -a for hdd on which this happens - no errors
Created attachment 78301 [details] hdparm -I of this hdd - all seems correct
And yes, this happens even without ugly tainting nvidia's module.
This was fixed in commit 0548bbb85337e532ca2ed697c3e9b227ff2ed4b4 which hit mainline in v3.6-rc3. It will hopefully be in the next stable release, v3.5.3, but that hasn't been released yet. Please try cherry-picking that fix, and let me know if that doesn't fix it. If it doesn't, we can reopen this bug and I'll take a closer look. But I'm 99.9% sure this should fix things for you.