[PATCH 4.14 018/237] ext4: improve explanation of a mount failure caused by a misconfigured kernel

Greg Kroah-Hartman
2020-02-27T13:52:51Z

From: Theodore Ts'o <tytso@mit.edu>

commit d65d87a07476aa17df2dcb3ad18c22c154315bec upstream.

If CONFIG_QFMT_V2 is not enabled, but CONFIG_QUOTA is enabled, when a
user tries to mount a file system with the quota or project quota
enabled, the kernel will emit a very confusing messsage:

EXT4-fs warning (device vdc): ext4_enable_quotas:5914: Failed to enable quota tracking (type=0, err=-3). Please run e2fsck to fix.
EXT4-fs (vdc): mount failed

We will now report an explanatory message indicating which kernel
configuration options have to be enabled, to avoid customer/sysadmin
confusion.

Link: https://lore.kernel.org/r/20200215012738.565735-1-tytso@mit.edu
Google-Bug-Id: 149093531
Fixes: 7c319d328505b778 ("ext4: make quota as first class supported feature")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/ext4/super.c | 14 ++++----------
1 file changed, 4 insertions(+), 10 deletions(-)

--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2863,17 +2863,11 @@ static int ext4_feature_set_ok(struct su
return 0;
}

-#ifndef CONFIG_QUOTA
- if (ext4_has_feature_quota(sb) && !readonly) {
+#if !defined(CONFIG_QUOTA) || !defined(CONFIG_QFMT_V2)
+ if (!readonly && (ext4_has_feature_quota(sb) ||
+ ext4_has_feature_project(sb))) {
ext4_msg(sb, KERN_ERR,
- "Filesystem with quota feature cannot be mounted RDWR "
- "without CONFIG_QUOTA");
- return 0;
- }
- if (ext4_has_feature_project(sb) && !readonly) {
- ext4_msg(sb, KERN_ERR,
- "Filesystem with project quota feature cannot be mounted RDWR "
- "without CONFIG_QUOTA");
+ "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
return 0;
}
#endif /* CONFIG_QUOTA */