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* JFFS2 : non-existent inode
@ 2009-03-04  5:43 AMUL KUMAR SAHA
  2009-03-09 13:51 ` David Woodhouse
  0 siblings, 1 reply; 5+ messages in thread
From: AMUL KUMAR SAHA @ 2009-03-04  5:43 UTC (permalink / raw)
  To: dwmw2; +Cc: linux-mtd

Hello David,

Environment : Flex-OneNAND 8Gb, Apollon Board, linux-2.6.26

I have just started with JFFS2  .  

We were running fsstress on 5 Boards for 5 Days .
On 2 out of 5 boards, we observed the message "requestied to read an nonexistent ino",
On Repetition, the BUG seems to be random.

Dwelled inside the code and thought of a possible scenario for the occurence.
I found the following explanation to it, appropriate; to my minimal knowledge :

1) 2 or more processes(say, P1 and P2) handling GC(jffs2_gc_fetch_inode) enter the function jffs2_iget almost together, before getting a mutex_lock.
2) When a request for a lock is raised, one of the processes(P1) gets the mutex_lock(&f->sem) and the other one waits.
3) P1 deletes the inode-cache(f->inocache), and releases the lock.
4) Now, when P2 ends up calling jffs2_do_read_inode with 'inode->ino' available locally in that function (unaware of the fact that, this particular inode was just destroyed).
5) JFFS2-Error with the message "requestied to read an nonexistent ino" is displayed.

In the mean time, I have come up with my own fix to this situation. Just wanting to know if my explanation makes sense, so that I can go ahead with posting the patch in mailing-list.

Thanks and Regards,

Amul Kumar Saha
Memory Solutions Group
Samsung India Software Operations

^ permalink raw reply	[flat|nested] 5+ messages in thread
* JFFS2 : non-existent inode
@ 2012-02-12 19:24 geraldwalden
  0 siblings, 0 replies; 5+ messages in thread
From: geraldwalden @ 2012-02-12 19:24 UTC (permalink / raw)
  To: linux-mtd

Hello:

Environment : Arm7 custom SBC, linux-2.6.26 

On a select number of our units (in the field) we observe the message "requestied to read an nonexistent ino" after performing a write to the flash and then performing an "ls -al" of the file we just wrote.

I am trying to pick up on the below thread that looks promising - yet has no resolution to it:

http://lists.infradead.org/pipermail/linux-mtd/2009-March/024836.html

Because I am encountering what looks to be the same problem as the above I am assuming I may be encountering the same problem.

Does anyone have any advice for me on how to pick up where the thread leaves off?  It seems to indicate that there was a real bug, or patch that might be necessary, yet after all this time (since the thread was active), I see no further references to the same - or a similar issue.

Am I to assume that a patch was created for this problem?  Is there something more I can add with respect to debug information / tracebacks / dumps / instrumentation to provide more information so I can bring this issue to the forefront again?  

Thanks for providing me with any direction as to how I can bring this issue back up as an active issue.

Jerry

^ permalink raw reply	[flat|nested] 5+ messages in thread
end of thread, other threads:[~2012-02-12 19:24 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2009-03-04  5:43 JFFS2 : non-existent inode AMUL KUMAR SAHA
2009-03-09 13:51 ` David Woodhouse
2009-03-11 15:10   ` Amul Kumar Saha
2009-03-11 15:18     ` David Woodhouse
  -- strict thread matches above, loose matches on Subject: below --
2012-02-12 19:24 geraldwalden

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