NFS: Fix wakeup of __nfs_lookup_revalidate() in unblock_revalidate()

Trond Myklebust · Trond Myklebust · commit 1db3a48e83bb · 2025-07-22T08:10:41.000-04:00
Use store_release_wake_up() to add the appropriate memory barrier before calling wake_up_var(&dentry->d_fsdata). Reported-by: Lukáš Hejtmánek<xhejtman@ics.muni.cz> Suggested-by: Santosh Pradhan <santosh.pradhan@gmail.com> Link: https://lore.kernel.org/all/18945D18-3EDB-4771-B019-0335CE671077@ics.muni.cz/ Fixes: 99bc9f2 ("NFS: add barriers when testing for NFS_FSDATA_BLOCKED") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
@@ -1828,9 +1828,7 @@ static void block_revalidate(struct dentry *dentry)
 
 static void unblock_revalidate(struct dentry *dentry)
 {
-	/* store_release ensures wait_var_event() sees the update */
-	smp_store_release(&dentry->d_fsdata, NULL);
-	wake_up_var(&dentry->d_fsdata);
+	store_release_wake_up(&dentry->d_fsdata, NULL);
 }
 
 /*

Original file line number	Diff line number	Diff line change
`@@ -1828,9 +1828,7 @@ static void block_revalidate(struct dentry *dentry)`
`1828`	`1828`
`1829`	`1829`	`static void unblock_revalidate(struct dentry *dentry)`
`1830`	`1830`	`{`
`1831`		`- /* store_release ensures wait_var_event() sees the update */`
`1832`		`- smp_store_release(&dentry->d_fsdata, NULL);`
`1833`		`- wake_up_var(&dentry->d_fsdata);`
	`1831`	`+ store_release_wake_up(&dentry->d_fsdata, NULL);`
`1834`	`1832`	`}`
`1835`	`1833`
`1836`	`1834`	`/*`