Patch "NFSD: narrow nfsd_mutex protection in nfsd thread" has been added to the 5.15-stable tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



This is a note to let you know that I've just added the patch titled

    NFSD: narrow nfsd_mutex protection in nfsd thread

to the 5.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     nfsd-narrow-nfsd_mutex-protection-in-nfsd-thread.patch
and it can be found in the queue-5.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 49f52c73fa67e8e823291c3ff3f600108bf659b9
Author: NeilBrown <neilb@xxxxxxx>
Date:   Mon Nov 29 15:51:25 2021 +1100

    NFSD: narrow nfsd_mutex protection in nfsd thread
    
    [ Upstream commit 9d3792aefdcda71d20c2b1ecc589c17ae71eb523 ]
    
    There is nothing happening in the start of nfsd() that requires
    protection by the mutex, so don't take it until shutting down the thread
    - which does still require protection - but only for nfsd_put().
    
    Signed-off-by: NeilBrown <neilb@xxxxxxx>
    [ cel: address merge conflict with fd2468fa1301 ]
    Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>

diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 16884a90e1ab0..eb8cc4d914fee 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -932,9 +932,6 @@ nfsd(void *vrqstp)
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 	int err;
 
-	/* Lock module and set up kernel thread */
-	mutex_lock(&nfsd_mutex);
-
 	/* At this point, the thread shares current->fs
 	 * with the init process. We need to create files with the
 	 * umask as defined by the client instead of init's umask. */
@@ -954,7 +951,6 @@ nfsd(void *vrqstp)
 	allow_signal(SIGINT);
 	allow_signal(SIGQUIT);
 
-	mutex_unlock(&nfsd_mutex);
 	atomic_inc(&nfsdstats.th_cnt);
 
 	set_freezable();
@@ -983,7 +979,6 @@ nfsd(void *vrqstp)
 	flush_signals(current);
 
 	atomic_dec(&nfsdstats.th_cnt);
-	mutex_lock(&nfsd_mutex);
 
 out:
 	/* Take an extra ref so that the svc_put in svc_exit_thread()
@@ -995,10 +990,11 @@ nfsd(void *vrqstp)
 	svc_exit_thread(rqstp);
 
 	/* Now if needed we call svc_destroy in appropriate context */
+	mutex_lock(&nfsd_mutex);
 	nfsd_put(net);
+	mutex_unlock(&nfsd_mutex);
 
 	/* Release module */
-	mutex_unlock(&nfsd_mutex);
 	module_put_and_kthread_exit(0);
 	return 0;
 }




[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux