由于从 13.10 升级到 14.04（使用do-release-upgrade），我的计算机（Sony vgn-sz1vp）在启动时挂起 4 分钟。
[ 1.015598] tpm_tis 00:06: 1.2 TPM (device-id 0xB, rev-id 16)
[ 1.019920] ACPI: Battery Slot [BAT1] (battery present)
[ 1.321725] isapnp: No Plug & Play device found
[ 93.668058] random: nonblocking pool is initialized
[ 121.040029] tpm_tis 00:06: Operation Timed out
[ 121.052385] tpm_tis 00:06: A TPM error (-62) occurred attempting to determine the timeouts
[ 241.088029] tpm_tis 00:06: Operation Timed out
[ 241.100484] tpm_tis 00:06: Could not get TPM timeouts …