diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h
index d5868f5514d3..abdd1b66f6b9 100644
--- a/fs/cachefiles/internal.h
+++ b/fs/cachefiles/internal.h
@@ -270,6 +270,8 @@ extern int cachefiles_remove_object_xattr(struct cachefiles_cache *cache,
 					  struct cachefiles_object *object,
 					  struct dentry *dentry);
 extern void cachefiles_prepare_to_write(struct fscache_cookie *cookie);
+extern bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume);
+extern int cachefiles_check_volume_xattr(struct cachefiles_volume *volume);
 
 /*
  * Error handling
diff --git a/fs/cachefiles/volume.c b/fs/cachefiles/volume.c
index 4a14f5e72764..89df0ba8ba5e 100644
--- a/fs/cachefiles/volume.c
+++ b/fs/cachefiles/volume.c
@@ -22,7 +22,8 @@ void cachefiles_acquire_volume(struct fscache_volume *vcookie)
 	struct dentry *vdentry, *fan;
 	size_t len;
 	char *name;
-	int n_accesses, i;
+	bool is_new = false;
+	int ret, n_accesses, i;
 
 	_enter("");
 
@@ -43,11 +44,29 @@ void cachefiles_acquire_volume(struct fscache_volume *vcookie)
 	memcpy(name + 1, vcookie->key + 1, len);
 	name[len + 1] = 0;
 
-	vdentry = cachefiles_get_directory(cache, cache->store, name, NULL);
+retry:
+	vdentry = cachefiles_get_directory(cache, cache->store, name, &is_new);
 	if (IS_ERR(vdentry))
 		goto error_name;
 	volume->dentry = vdentry;
 
+	if (is_new) {
+		if (!cachefiles_set_volume_xattr(volume))
+			goto error_dir;
+	} else {
+		ret = cachefiles_check_volume_xattr(volume);
+		if (ret < 0) {
+			if (ret != -ESTALE)
+				goto error_dir;
+			inode_lock_nested(d_inode(cache->store), I_MUTEX_PARENT);
+			cachefiles_bury_object(cache, NULL, cache->store, vdentry,
+					       FSCACHE_VOLUME_IS_WEIRD);
+			cachefiles_put_directory(volume->dentry);
+			cond_resched();
+			goto retry;
+		}
+	}
+	
 	for (i = 0; i < 256; i++) {
 		sprintf(name, "@%02x", i);
 		fan = cachefiles_get_directory(cache, vdentry, name, NULL);
@@ -74,6 +93,7 @@ void cachefiles_acquire_volume(struct fscache_volume *vcookie)
 error_fan:
 	for (i = 0; i < 256; i++)
 		cachefiles_put_directory(volume->fanout[i]);
+error_dir:
 	cachefiles_put_directory(volume->dentry);
 error_name:
 	kfree(name);
@@ -114,5 +134,6 @@ void cachefiles_free_volume(struct fscache_volume *vcookie)
 void cachefiles_withdraw_volume(struct cachefiles_volume *volume)
 {
 	fscache_withdraw_volume(volume->vcookie);
+	cachefiles_set_volume_xattr(volume);
 	__cachefiles_free_volume(volume);
 }
diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c
index 0601c46a22ef..4881da2c189a 100644
--- a/fs/cachefiles/xattr.c
+++ b/fs/cachefiles/xattr.c
@@ -179,3 +179,85 @@ void cachefiles_prepare_to_write(struct fscache_cookie *cookie)
 		cachefiles_end_secure(cache, saved_cred);
 	}
 }
+
+/*
+ * Set the state xattr on a volume directory.
+ */
+bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume)
+{
+	unsigned int len = volume->vcookie->coherency_len;
+	const void *p = volume->vcookie->coherency;
+	struct dentry *dentry = volume->dentry;
+	int ret;
+
+	_enter("%x,#%d", volume->vcookie->debug_id, len);
+
+	ret = cachefiles_inject_write_error();
+	if (ret == 0)
+		ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
+				   p, len, 0);
+	if (ret < 0) {
+		trace_cachefiles_vfs_error(NULL, d_inode(dentry), ret,
+					   cachefiles_trace_setxattr_error);
+		trace_cachefiles_vol_coherency(volume, d_inode(dentry)->i_ino,
+					       cachefiles_coherency_vol_set_fail);
+		if (ret != -ENOMEM)
+			cachefiles_io_error(
+				volume->cache, "Failed to set xattr with error %d", ret);
+	} else {
+		trace_cachefiles_vol_coherency(volume, d_inode(dentry)->i_ino,
+					       cachefiles_coherency_vol_set_ok);
+	}
+
+	_leave(" = %d", ret);
+	return ret == 0;
+}
+
+/*
+ * Check the consistency between the backing cache and the volume cookie.
+ */
+int cachefiles_check_volume_xattr(struct cachefiles_volume *volume)
+{
+	struct cachefiles_xattr *buf;
+	struct dentry *dentry = volume->dentry;
+	unsigned int len = volume->vcookie->coherency_len;
+	const void *p = volume->vcookie->coherency;
+	enum cachefiles_coherency_trace why;
+	ssize_t xlen;
+	int ret = -ESTALE;
+
+	_enter("");
+
+	buf = kmalloc(len, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	kdebug("COOK %*phN", (int)len, p);
+
+	xlen = cachefiles_inject_read_error();
+	if (xlen == 0)
+		xlen = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache, buf, len);
+	if (xlen >= 0)
+		kdebug("DISK %*phN", (int)xlen, buf);
+	if (xlen != len) {
+		if (xlen < 0) {
+			trace_cachefiles_vfs_error(NULL, d_inode(dentry), xlen,
+						   cachefiles_trace_getxattr_error);
+			if (xlen == -EIO)
+				cachefiles_io_error(
+					volume->cache,
+					"Failed to read xattr with error %zd", xlen);
+		}
+		why = cachefiles_coherency_vol_check_xattr;
+	} else if (memcmp(buf->data, p, len) != 0) {
+		why = cachefiles_coherency_vol_check_cmp;
+	} else {
+		why = cachefiles_coherency_vol_check_ok;
+		ret = 0;
+	}
+
+	trace_cachefiles_vol_coherency(volume, d_inode(dentry)->i_ino, why);
+	kfree(buf);
+	_leave(" = %d", ret);
+	return ret;
+}
diff --git a/fs/fscache/volume.c b/fs/fscache/volume.c
index e1a8e92a6adb..a57c6cbee858 100644
--- a/fs/fscache/volume.c
+++ b/fs/fscache/volume.c
@@ -205,15 +205,22 @@ static struct fscache_volume *fscache_alloc_volume(const char *volume_key,
 	size_t klen, hlen;
 	char *key;
 
+	if (!coherency_data)
+		coherency_len = 0;
+
 	cache = fscache_lookup_cache(cache_name, false);
 	if (IS_ERR(cache))
 		return NULL;
 
-	volume = kzalloc(sizeof(*volume), GFP_KERNEL);
+	volume = kzalloc(struct_size(volume, coherency, coherency_len),
+			 GFP_KERNEL);
 	if (!volume)
 		goto err_cache;
 
 	volume->cache = cache;
+	volume->coherency_len = coherency_len;
+	if (coherency_data)
+		memcpy(volume->coherency, coherency_data, coherency_len);
 	INIT_LIST_HEAD(&volume->proc_link);
 	INIT_WORK(&volume->work, fscache_create_volume_work);
 	refcount_set(&volume->ref, 1);
@@ -421,8 +428,11 @@ void __fscache_relinquish_volume(struct fscache_volume *volume,
 	if (WARN_ON(test_and_set_bit(FSCACHE_VOLUME_RELINQUISHED, &volume->flags)))
 		return;
 
-	if (invalidate)
+	if (invalidate) {
 		set_bit(FSCACHE_VOLUME_INVALIDATE, &volume->flags);
+	} else if (coherency_data) {
+		memcpy(volume->coherency, coherency_data, volume->coherency_len);
+	}
 
 	fscache_put_volume(volume, fscache_volume_put_relinquish);
 }
diff --git a/include/linux/fscache.h b/include/linux/fscache.h
index 0bdd5166d20b..9ad3e44418d2 100644
--- a/include/linux/fscache.h
+++ b/include/linux/fscache.h
@@ -87,6 +87,8 @@ struct fscache_volume {
 #define FSCACHE_VOLUME_COLLIDED_WITH	2	/* Volume was collided with */
 #define FSCACHE_VOLUME_ACQUIRE_PENDING	3	/* Volume is waiting to complete acquisition */
 #define FSCACHE_VOLUME_CREATING		4	/* Volume is being created on disk */
+	u8				coherency_len;	/* Length of the coherency data */
+	u8				coherency[];	/* Coherency data */
 };
 
 /*
diff --git a/include/trace/events/cachefiles.h b/include/trace/events/cachefiles.h
index ab1376ebc3ab..1172529b5b49 100644
--- a/include/trace/events/cachefiles.h
+++ b/include/trace/events/cachefiles.h
@@ -40,6 +40,7 @@ enum fscache_why_object_killed {
 	FSCACHE_OBJECT_NO_SPACE,
 	FSCACHE_OBJECT_WAS_RETIRED,
 	FSCACHE_OBJECT_WAS_CULLED,
+	FSCACHE_VOLUME_IS_WEIRD,
 };
 
 enum cachefiles_coherency_trace {
@@ -53,6 +54,11 @@ enum cachefiles_coherency_trace {
 	cachefiles_coherency_check_xattr,
 	cachefiles_coherency_set_fail,
 	cachefiles_coherency_set_ok,
+	cachefiles_coherency_vol_check_cmp,
+	cachefiles_coherency_vol_check_ok,
+	cachefiles_coherency_vol_check_xattr,
+	cachefiles_coherency_vol_set_fail,
+	cachefiles_coherency_vol_set_ok,
 };
 
 enum cachefiles_trunc_trace {
@@ -103,7 +109,8 @@ enum cachefiles_error_trace {
 	EM(FSCACHE_OBJECT_INVALIDATED,	"inval")		\
 	EM(FSCACHE_OBJECT_NO_SPACE,	"no_space")		\
 	EM(FSCACHE_OBJECT_WAS_RETIRED,	"was_retired")		\
-	E_(FSCACHE_OBJECT_WAS_CULLED,	"was_culled")
+	EM(FSCACHE_OBJECT_WAS_CULLED,	"was_culled")		\
+	E_(FSCACHE_VOLUME_IS_WEIRD,	"volume_weird")
 
 #define cachefiles_obj_ref_traces					\
 	EM(cachefiles_obj_get_ioreq,		"GET ioreq")		\
@@ -129,7 +136,12 @@ enum cachefiles_error_trace {
 	EM(cachefiles_coherency_check_type,	"BAD type")		\
 	EM(cachefiles_coherency_check_xattr,	"BAD xatt")		\
 	EM(cachefiles_coherency_set_fail,	"SET fail")		\
-	E_(cachefiles_coherency_set_ok,		"SET ok  ")
+	EM(cachefiles_coherency_set_ok,		"SET ok  ")		\
+	EM(cachefiles_coherency_vol_check_cmp,	"VOL BAD cmp ")		\
+	EM(cachefiles_coherency_vol_check_ok,	"VOL OK      ")		\
+	EM(cachefiles_coherency_vol_check_xattr,"VOL BAD xatt")		\
+	EM(cachefiles_coherency_vol_set_fail,	"VOL SET fail")		\
+	E_(cachefiles_coherency_vol_set_ok,	"VOL SET ok  ")
 
 #define cachefiles_trunc_traces						\
 	EM(cachefiles_trunc_dio_adjust,		"DIOADJ")		\
@@ -365,6 +377,32 @@ TRACE_EVENT(cachefiles_coherency,
 		      __entry->content)
 	    );
 
+TRACE_EVENT(cachefiles_vol_coherency,
+	    TP_PROTO(struct cachefiles_volume *volume,
+		     ino_t ino,
+		     enum cachefiles_coherency_trace why),
+
+	    TP_ARGS(volume, ino, why),
+
+	    /* Note that obj may be NULL */
+	    TP_STRUCT__entry(
+		    __field(unsigned int,			vol	)
+		    __field(enum cachefiles_coherency_trace,	why	)
+		    __field(u64,				ino	)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->vol	= volume->vcookie->debug_id;
+		    __entry->why	= why;
+		    __entry->ino	= ino;
+			   ),
+
+	    TP_printk("V=%08x %s i=%llx",
+		      __entry->vol,
+		      __print_symbolic(__entry->why, cachefiles_coherency_traces),
+		      __entry->ino)
+	    );
+
 TRACE_EVENT(cachefiles_prep_read,
 	    TP_PROTO(struct netfs_read_subrequest *sreq,
 		     enum netfs_read_source source,
