LU-7613 llite: changes to avoid cache corruption

ll_find_alias is responsible for getting alias for inode
which can be reused. Directories are assumed to have unique
alias, where in case of non-directories there can be multiple
aliases. In case of lustre there can be two type of aliases
i.e. discon_alias and invalid_alias. Usage of discon_alias in
case of non-directories may corrupt dcache and leads to kernel
crash. Changes made to avoid use of discon_alias in case of
non-directories.

Seagate-bug-id: MRP-2739, MRP-3601
Change-Id: Ieb9dabab0784bdb3c52e2cb32be1a766ffe55313
Signed-off-by: Lokesh Nagappa Jaliminche <lokesh.jaliminche@seagate.com>
Reviewed-by: Ujjwal Lanjewar <ujjwal.lanjewar@seagate.com>
Reviewed-by: Ashish Purkar <ashish.purkar@seagate.com>
Reviewed-by: Andrew Perepechko <andrew.perepechko@seagate.com>
Tested-by: Parinay Vijayprakash Kondekar <parinay.kondekar@seagate.com>
Reviewed-on: http://review.whamcloud.com/17732
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Niu Yawei <yawei.niu@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/lustre/llite/namei.c b/lustre/llite/namei.c
index 1c17b50..1427c6a 100644 (file)
--- a/lustre/llite/namei.c
+++ b/lustre/llite/namei.c
@@ -399,7 +399,8 @@ static struct dentry *ll_find_alias(struct inode *inode, struct dentry *dentry)
                LASSERT(alias != dentry);
 
                spin_lock(&alias->d_lock);
-               if (alias->d_flags & DCACHE_DISCONNECTED)
+               if ((alias->d_flags & DCACHE_DISCONNECTED) &&
+                   S_ISDIR(inode->i_mode))
                        /* LASSERT(last_discon == NULL); LU-405, bz 20055 */
                        discon_alias = alias;
                else if (alias->d_parent == dentry->d_parent             &&

diff --git a/lustre/tests/parallel-scale-nfs.sh b/lustre/tests/parallel-scale-nfs.sh
index 0f8fead..4f698c3 100755 (executable)
--- a/lustre/tests/parallel-scale-nfs.sh
+++ b/lustre/tests/parallel-scale-nfs.sh
@@ -12,6 +12,7 @@ fi
 . ${CONFIG:=$LUSTRE/tests/cfg/$NAME.sh}
 init_logging
 
+racer=$LUSTRE/tests/racer/racer.sh
 . $LUSTRE/tests/setup-nfs.sh
 
 check_and_setup_lustre
@@ -98,6 +99,11 @@ test_iorfpp() {
 }
 run_test iorfpp "iorfpp"
 
+test_racer_on_nfs() {
+       $racer $CLIENTS
+}
+run_test racer_on_nfs "racer on NFS client"
+
 # cleanup nfs
 cleanup_nfs "$MOUNT" "$lustre_client" "$CLIENTS" || \
     error_noexit false "cleanup_nfs failed"