From: Valeriy Vdovin <valeriy.vdo...@virtuozzo.com> +CONFIG_OVERLAY_FS_INDEX=y +CONFIG_OVERLAY_FS_NFS_EXPORT=y
Docker uses overlayfs. Lately, I've been testing checkpoint/restore of fs notifications that were setup on top of overlayfs. I've found out that criu is not able to dump opened file descriptors of fanotify when nfs_export parameter is off. The details of that problem: at checkpoint/dump criu wants to dump fanotify fd and uses 'open_by_handle_at' with fhandle of the subject descriptor. Kernel needs to decode fhandle to convert it to inode, for that it uses mnt->mnt_sb->s_export_op->fh_to_dentry. For overlayfs mount s_export_op is only filled with valid exportfs function if nfs_export flag is true. nfs_export in its turn depends on index=on option. One way to enable them is to extend mount options with string "nfs_export=on,index=on" during call to mount. Another way which we discussed - is to tune defaults for both values to true. https://jira.sw.ru/browse/PSBM-104961 Signed-off-by: Valeriy Vdovin <valeriy.vdo...@virtuozzo.com> (cherry picked from vz8 commit 7fe31a28bad084949cd927fbce553d9152631e15) Signed-off-by: Andrey Zhadchenko <andrey.zhadche...@virtuozzo.com> --- redhat/configs/custom-overrides/generic/CONFIG_OVERLAY_FS_INDEX | 1 + redhat/configs/custom-overrides/generic/CONFIG_OVERLAY_FS_NFS_EXPORT | 1 + 2 files changed, 2 insertions(+) create mode 100644 redhat/configs/custom-overrides/generic/CONFIG_OVERLAY_FS_INDEX create mode 100644 redhat/configs/custom-overrides/generic/CONFIG_OVERLAY_FS_NFS_EXPORT diff --git a/redhat/configs/custom-overrides/generic/CONFIG_OVERLAY_FS_INDEX b/redhat/configs/custom-overrides/generic/CONFIG_OVERLAY_FS_INDEX new file mode 100644 index 0000000..c61cab2 --- /dev/null +++ b/redhat/configs/custom-overrides/generic/CONFIG_OVERLAY_FS_INDEX @@ -0,0 +1 @@ +CONFIG_OVERLAY_FS_INDEX=y diff --git a/redhat/configs/custom-overrides/generic/CONFIG_OVERLAY_FS_NFS_EXPORT b/redhat/configs/custom-overrides/generic/CONFIG_OVERLAY_FS_NFS_EXPORT new file mode 100644 index 0000000..a3fcd011 --- /dev/null +++ b/redhat/configs/custom-overrides/generic/CONFIG_OVERLAY_FS_NFS_EXPORT @@ -0,0 +1 @@ +CONFIG_OVERLAY_FS_NFS_EXPORT=y -- 1.8.3.1 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
