Both the 'noac' and 'actimeo=0' mount options should ensure that attributes are not cached, however a bug in nfs_attribute_timeout() means that currently, the attributes may in fact get cached for up to one jiffy. This has been seen to cause corruption in some applications. The reason for the bug is that the time_in_range() test returns 'true' as long as the current time lies between nfsi->read_cache_jiffies and nfsi->read_cache_jiffies + nfsi->attrtimeo. In other words, if jiffies equals nfsi->read_cache_jiffies, then we still cache the attribute data. Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> --- fs/nfs/inode.c | 7 +++++++ 1 files changed, 7 insertions(+), 0 deletions(-) diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 5cb3345..38f06d3 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -707,6 +707,13 @@ int nfs_attribute_timeout(struct inode *inode) if (nfs_have_delegation(inode, FMODE_READ)) return 0; + /* + * Special case: if the attribute timeout is set to 0, then we + * treat the cache as having expired (unless we + * have a delegation). + */ + if (nfsi->attrtimeo == 0) + return 1; return !time_in_range(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo); } -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
