2013-03-07 07:21:35

by Konstantin Khlebnikov

Subject: [PATCH linux-next] procfs: fix rcu-lock/unlock in proc_reg_open() and proc_reg_release()

fix for a21813be23329e2788164eab532e79cb0e513cfc (linux-next)
"procfs: improve scaling in proc"

Signed-off-by: Konstantin Khlebnikov <[email protected]>
Cc: Nathan Zimmer <[email protected]>
Cc: Andrew Morton <[email protected]>
---
fs/proc/inode.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 6cccc4d..073846c 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -352,7 +352,7 @@ static int proc_reg_open(struct inode *inode, struct file *file)
atomic_inc(&pde->pde_users);
open = fops->open;
release = fops->release;
- rcu_read_lock();
+ rcu_read_unlock();

if (open)
rv = open(inode, file);
@@ -400,6 +400,7 @@ static int proc_reg_release(struct inode *inode, struct file *file)
rcu_read_lock();
fops = rcu_dereference(pde->proc_fops);
if (!fops) {
+ rcu_read_unlock();
/*
* Can't simply exit, __fput() will think that everything is OK,
* and move on to freeing struct file. remove_proc_entry() will

2013-03-13 00:06:53

by Peter Hurley

Subject: Re: [PATCH linux-next] procfs: fix rcu-lock/unlock in proc_reg_open() and proc_reg_release()

On Thu, 2013-03-07 at 11:21 +0400, Konstantin Khlebnikov wrote:
> fix for a21813be23329e2788164eab532e79cb0e513cfc (linux-next)
> "procfs: improve scaling in proc"
>
> Signed-off-by: Konstantin Khlebnikov <[email protected]>
> Cc: Nathan Zimmer <[email protected]>
> Cc: Andrew Morton <[email protected]>

Konstantin,

Thanks for fixing this. Now -next boots once again :)

Regards,
Peter Hurley