Hi Jiang,

FYI, my NFSROOT mount breaks since this commit:

tree:   git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git pci/jiang-pcie-cap
head:   787d5164cb7a057cab67250b63c3cee46e98f1ad
commit: e9b21631b4f419d942de54e0a7cee51f77ac17ac [5/40] PCI/core: Use PCI Express Capability accessors

[  477.256277] fc50          307200 vdf  driver: virtio_blk
[  477.257945] DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify explicit textual name for "root=" boot option.
[  477.260925] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)
[  477.261877] Pid: 1, comm: swapper/0 Not tainted 3.6.0-rc1+ #2572
[  477.261877] Call Trace:
[  477.261877]  [<ffffffff819f7082>] panic+0xc9/0x1d2
[  477.261877]  [<ffffffff82214016>] mount_block_root+0x1e6/0x1fd
[  477.261877]  [<ffffffff82214290>] mount_root+0x144/0x14f
[  477.261877]  [<ffffffff82214408>] prepare_namespace+0x16d/0x1a6
[  477.261877]  [<ffffffff82213cfa>] kernel_init+0x1bb/0x1c0
[  477.261877]  [<ffffffff8221356f>] ? do_early_param+0x8c/0x8c
[  477.261877]  [<ffffffff81a110c4>] kernel_thread_helper+0x4/0x10
[  477.261877]  [<ffffffff81a09430>] ? retint_restore_args+0x13/0x13
[  477.261877]  [<ffffffff82213b3f>] ? start_kernel+0x37e/0x37e
[  477.261877]  [<ffffffff81a110c0>] ? gs_change+0x13/0x13
[  477.261877] Rebooting in 10 seconds..

Thanks,
Fengguang