Bug 7826

Summary:	BUG: at mm/truncate.c:425 invalidate_inode_pages2_range()
Product:	File System	Reporter:	Andrew Clayton (andrew)
Component:	NFS	Assignee:	Andrew Morton (akpm)
Status:	RESOLVED CODE_FIX
Severity:	normal	CC:	bunk
Priority:	P2
Hardware:	i386
OS:	Linux
Kernel Version:	2.6.20-rc5	Subsystem:
Regression:	---	Bisected commit-id:

Description Andrew Clayton 2007-01-15 04:30:13 UTC

Most recent kernel where this bug did *NOT* occur:

2.6.19

Distribution:

FC6 (64bit)

Hardware Environment:

Single AMD64 3500+, 1GB RAM

Software Environment:

Stock FC6 with latest updates

gcc-4.1.1-51.fc6
binutils-2.17.50.0.6-2.fc6

Problem Description:

After some time of activity I get 

BUG: at /home/andrew/src/linux-2.6/mm/truncate.c:425 invalidate_inode_pages2_range()

Call Trace:
 [<ffffffff8024c335>] invalidate_inode_pages2_range+0x2a5/0x2d0
 [<ffffffff802d551f>] nfs_revalidate_mapping+0xaf/0x160
 [<ffffffff802d3ac5>] nfs_file_read+0x65/0xe0
 [<ffffffff80263e5f>] do_sync_read+0xcf/0x120
 [<ffffffff802d38d0>] nfs_file_open+0x0/0x80
 [<ffffffff802394c0>] autoremove_wake_function+0x0/0x30
 [<ffffffff8026255d>] do_filp_open+0x2d/0x40
 [<ffffffff804fbda9>] mutex_lock+0x9/0x20
 [<ffffffff802647ba>] vfs_read+0xba/0x180
 [<ffffffff80264c03>] sys_read+0x53/0x90
 [<ffffffff80209a0e>] system_call+0x7e/0x83

In dmesg.


Steps to reproduce:

I have some NFS mounted fileystems including my home dir

/dev/sda1 on / type ext3 (rw)
/dev/proc on /proc type proc (rw)
/dev/sys on /sys type sysfs (rw)
/dev/devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/shm on /dev/shm type tmpfs (rw)
homes.systems.pccl.info:/home/andrew on /home/andrew type nfs
(rw,nfsvers=3,hard,intr,rsize=16384,wsize=16384,addr=192.168.1.5)
homes.systems.pccl.info:/home/storage/apps on /mnt/autofs/apps type nfs
(ro,nfsvers=3,hard,intr,rsize=16384,addr=192.168.1.5)


I was last using 2.6.19 where this didn't occur. I then updated to 2.6.20-rc4
where I noticed this BUG.

This morning I updated to 2.6.20-rc5. It seemed to take a bit longer for this
BUG to happen, before it seemed to happen with sylpheed-claws where its mail
files are stored in my NFS mounted home dir, this time I noticed it after I had
started mplayer on an ogg vorbis file out of my NFS mounted home dir. 


Cheers,

Comment 1 Trond Myklebust 2007-01-15 08:18:01 UTC

Not a bug!

It is perfectly legal and acceptable for the user to ^C out of a hanging
process. In that case, the NFS client will also abandon the attempt to
invalidate the page cache, and just defer doing so until the next process needs
to access that data.

That WARN_ON crap that Andrew merged into invalidate_inode_pages2_range() needs
to be thrown out.

Comment 2 Nick Piggin 2007-01-30 00:10:55 UTC

Agreed, this is not a bug if the callers handle it correctly. Can we send a
patch to remove the WARN_ON_ONCE, and close this?

Comment 3 Andrew Morton 2007-01-30 00:26:23 UTC

we already did, I think.