* [PATCH] NFSD: Decrease nfsd_users in nfsd_startup_generic fail
@ 2014-07-30 13:26 Kinglong Mee
2014-07-30 14:16 ` J. Bruce Fields
0 siblings, 1 reply; 4+ messages in thread
From: Kinglong Mee @ 2014-07-30 13:26 UTC (permalink / raw)
To: J. Bruce Fields; +Cc: Linux NFS Mailing List, kinglongmee
If nfsd_startup_generic fail, nfsd_users isn't decreased right now.
NFSD restarts will return 0 at the first nfsd_users checking,
after that, nfs4_state_start_net() will meet a bad laundry_wq
(I meet NULL), after nfsd4_grace timeout, the kernel will crash.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
---
fs/nfsd/nfssvc.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 5d026dc..752d56b 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -221,7 +221,8 @@ static int nfsd_startup_generic(int nrservs)
*/
ret = nfsd_racache_init(2*nrservs);
if (ret)
- return ret;
+ goto dec_users;
+
ret = nfs4_state_start();
if (ret)
goto out_racache;
@@ -229,6 +230,8 @@ static int nfsd_startup_generic(int nrservs)
out_racache:
nfsd_racache_shutdown();
+dec_users:
+ nfsd_users--;
return ret;
}
--
1.9.3
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] NFSD: Decrease nfsd_users in nfsd_startup_generic fail
2014-07-30 13:26 [PATCH] NFSD: Decrease nfsd_users in nfsd_startup_generic fail Kinglong Mee
@ 2014-07-30 14:16 ` J. Bruce Fields
2014-07-31 12:56 ` Kinglong Mee
0 siblings, 1 reply; 4+ messages in thread
From: J. Bruce Fields @ 2014-07-30 14:16 UTC (permalink / raw)
To: Kinglong Mee; +Cc: Linux NFS Mailing List
Thanks!
On Wed, Jul 30, 2014 at 09:26:05PM +0800, Kinglong Mee wrote:
> If nfsd_startup_generic fail, nfsd_users isn't decreased right now.
Looks like that should only fail in out of memory cases?
> NFSD restarts will return 0 at the first nfsd_users checking,
> after that, nfs4_state_start_net() will meet a bad laundry_wq
> (I meet NULL), after nfsd4_grace timeout, the kernel will crash.
So this was introduced with 4539f14981ce02d48b212786a41c8bcfb62851b4
"nfsd: replace boolean nfsd_up flag by users counter".
--b.
>
> Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
> ---
> fs/nfsd/nfssvc.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
> index 5d026dc..752d56b 100644
> --- a/fs/nfsd/nfssvc.c
> +++ b/fs/nfsd/nfssvc.c
> @@ -221,7 +221,8 @@ static int nfsd_startup_generic(int nrservs)
> */
> ret = nfsd_racache_init(2*nrservs);
> if (ret)
> - return ret;
> + goto dec_users;
> +
> ret = nfs4_state_start();
> if (ret)
> goto out_racache;
> @@ -229,6 +230,8 @@ static int nfsd_startup_generic(int nrservs)
>
> out_racache:
> nfsd_racache_shutdown();
> +dec_users:
> + nfsd_users--;
> return ret;
> }
>
> --
> 1.9.3
>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] NFSD: Decrease nfsd_users in nfsd_startup_generic fail
2014-07-30 14:16 ` J. Bruce Fields
@ 2014-07-31 12:56 ` Kinglong Mee
2014-08-01 20:29 ` J. Bruce Fields
0 siblings, 1 reply; 4+ messages in thread
From: Kinglong Mee @ 2014-07-31 12:56 UTC (permalink / raw)
To: J. Bruce Fields; +Cc: Linux NFS Mailing List, kinglongmee
On 7/30/2014 22:16, J. Bruce Fields wrote:
> Thanks!
>
> On Wed, Jul 30, 2014 at 09:26:05PM +0800, Kinglong Mee wrote:
>> If nfsd_startup_generic fail, nfsd_users isn't decreased right now.
>
> Looks like that should only fail in out of memory cases?
Yes, it is.
I found this problem through reviewing code.
>
>> NFSD restarts will return 0 at the first nfsd_users checking,
>> after that, nfs4_state_start_net() will meet a bad laundry_wq
>> (I meet NULL), after nfsd4_grace timeout, the kernel will crash.
>
> So this was introduced with 4539f14981ce02d48b212786a41c8bcfb62851b4
> "nfsd: replace boolean nfsd_up flag by users counter".
Yes, I forget adding it.
thanks,
Kinglong Mee
>> Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
>> ---
>> fs/nfsd/nfssvc.c | 5 ++++-
>> 1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
>> index 5d026dc..752d56b 100644
>> --- a/fs/nfsd/nfssvc.c
>> +++ b/fs/nfsd/nfssvc.c
>> @@ -221,7 +221,8 @@ static int nfsd_startup_generic(int nrservs)
>> */
>> ret = nfsd_racache_init(2*nrservs);
>> if (ret)
>> - return ret;
>> + goto dec_users;
>> +
>> ret = nfs4_state_start();
>> if (ret)
>> goto out_racache;
>> @@ -229,6 +230,8 @@ static int nfsd_startup_generic(int nrservs)
>>
>> out_racache:
>> nfsd_racache_shutdown();
>> +dec_users:
>> + nfsd_users--;
>> return ret;
>> }
>>
>> --
>> 1.9.3
>>
>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] NFSD: Decrease nfsd_users in nfsd_startup_generic fail
2014-07-31 12:56 ` Kinglong Mee
@ 2014-08-01 20:29 ` J. Bruce Fields
0 siblings, 0 replies; 4+ messages in thread
From: J. Bruce Fields @ 2014-08-01 20:29 UTC (permalink / raw)
To: Kinglong Mee; +Cc: Linux NFS Mailing List
On Thu, Jul 31, 2014 at 08:56:13PM +0800, Kinglong Mee wrote:
> On 7/30/2014 22:16, J. Bruce Fields wrote:
> > Thanks!
> >
> > On Wed, Jul 30, 2014 at 09:26:05PM +0800, Kinglong Mee wrote:
> >> If nfsd_startup_generic fail, nfsd_users isn't decreased right now.
> >
> > Looks like that should only fail in out of memory cases?
>
> Yes, it is.
> I found this problem through reviewing code.
Got it, thanks! Applying for 3.17 and stable.
--b.
>
> >
> >> NFSD restarts will return 0 at the first nfsd_users checking,
> >> after that, nfs4_state_start_net() will meet a bad laundry_wq
> >> (I meet NULL), after nfsd4_grace timeout, the kernel will crash.
> >
> > So this was introduced with 4539f14981ce02d48b212786a41c8bcfb62851b4
> > "nfsd: replace boolean nfsd_up flag by users counter".
>
> Yes, I forget adding it.
>
> thanks,
> Kinglong Mee
>
> >> Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
> >> ---
> >> fs/nfsd/nfssvc.c | 5 ++++-
> >> 1 file changed, 4 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
> >> index 5d026dc..752d56b 100644
> >> --- a/fs/nfsd/nfssvc.c
> >> +++ b/fs/nfsd/nfssvc.c
> >> @@ -221,7 +221,8 @@ static int nfsd_startup_generic(int nrservs)
> >> */
> >> ret = nfsd_racache_init(2*nrservs);
> >> if (ret)
> >> - return ret;
> >> + goto dec_users;
> >> +
> >> ret = nfs4_state_start();
> >> if (ret)
> >> goto out_racache;
> >> @@ -229,6 +230,8 @@ static int nfsd_startup_generic(int nrservs)
> >>
> >> out_racache:
> >> nfsd_racache_shutdown();
> >> +dec_users:
> >> + nfsd_users--;
> >> return ret;
> >> }
> >>
> >> --
> >> 1.9.3
> >>
> >
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2014-08-01 20:29 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2014-07-30 13:26 [PATCH] NFSD: Decrease nfsd_users in nfsd_startup_generic fail Kinglong Mee
2014-07-30 14:16 ` J. Bruce Fields
2014-07-31 12:56 ` Kinglong Mee
2014-08-01 20:29 ` J. Bruce Fields
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).