From 4251c94833aa516c1fc7a0f8f504a26eadd4b91e Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Mon, 9 May 2011 15:22:15 -0400 Subject: NFS: Revert NFSROOT default mount options Marek Belisko reports that recent attempts to fix regressions in NFSROOT have broken his configuration: > After update from 2.6.38-rc8 to 2.6.38 is mounting rootfs over nfs not possible. > Log: > VFS: Mounted root (nfs filesystem) on device 0:14. > Freeing init memory: 132K > nfs: server 10.146.1.21 not responding, still trying > nfs: server 10.146.1.21 not responding, still trying > > This is never ending. I make short bisect (not too much commits > between versions) > and bad commit was reported: 53d4737580535e073963b91ce87d4216e434fab5 > > NFS: NFSROOT should default to "proto=udp" > > I've tested on mini2440 board (DM9000, static IP). > Is there some missing option or something else to be checked? An examination of a network trace captured during the failure shows that the mount is actually succeeding, but that the client is not seeing READ replies larger than 16KB. This could be a local packet filtering issue on the client, but we didn't troubleshoot this further because of the reported "git bisect" result. Last fall we removed the ad hoc mount option parser in fs/nfs/nfsroot.c in favor of using the main parser in fs/nfs/super.c (see commit 56463e50 "NFS: Use super.c for NFSROOT mount option parsing"). That commit changed the default NFSROOT mount options to be the same as those employed by user space mounts. As it turns out, these new default mount options are not tolerated by many embedded systems. So far these problems have been due to specific behavior of certain embedded NICs. The NFS community does not have such hardware on hand for running tests. Commit 53d47375 recently introduced a clean way to specify default mount options for NFSROOT, so we can now easily restore the traditional defaults for NFSROOT: vers=2,udp,rsize=4096,wsize=4096 This should revert the new default NFSROOT mount options introduced with commit 56463e50. Tested-by: Marek Belisto Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust diff --git a/fs/nfs/nfsroot.c b/fs/nfs/nfsroot.c index c541093..c4744e1 100644 --- a/fs/nfs/nfsroot.c +++ b/fs/nfs/nfsroot.c @@ -87,7 +87,7 @@ #define NFS_ROOT "/tftpboot/%s" /* Default NFSROOT mount options. */ -#define NFS_DEF_OPTIONS "udp" +#define NFS_DEF_OPTIONS "vers=2,udp,rsize=4096,wsize=4096" /* Parameters passed from the kernel command line */ static char nfs_root_parms[256] __initdata = ""; -- cgit v0.10.2