Patch Name: PHKL_23327

Patch Description: s700 10.20 JFS sync/freeze/flush 'dirty inval' panics

Creation Date: 01/02/06

Post Date:  01/02/07

Hardware Platforms - OS Releases:
	s700: 10.20

Products: N/A

Filesets:
	JournalFS.VXFS-BASE-KRN

Automatic Reboot?: Yes

Status: General Superseded

Critical:
	Yes
	PHKL_23327: PANIC
	PHKL_17526: PANIC

Path Name: /hp-ux_patches/s700/10.X/PHKL_23327

Symptoms:
	PHKL_23327:
	(SR: 8606173382   CR: JAGad42640)
	Data Page Fault in vx_rwsleep_unlock()/vx_igunlock()
	invoked from vx_iflush() or vx_fsflushi(). This happens
	under heavy stress to VxFS filesystems. Stack of the
	panic thread may look like:

		panic+0x10
		report_trap_or_int_and_panic+0xe8
		trap+0xa48
		thandler+0xb7c
		vx_rwsleep_unlock+0xc
		vx_igunlock+0x14
		vx_iflush+0x1fc
		vx_iflush_thread+0x70
		vx_startdaemon+0xac
		vx_postinit+0x74
		vx_sync+0x14
		update+0x6c
		sync+0x20

	PHKL_17526:
	(SR: 1653285320 DTS: JAGaa44494)
	System panics with "panic:  dirty inval" message.  A stack
	trace might look like:

	        panic+0x10
	        brelse+0x230
	        vx_brelse_bp+0x34
	        vx_brelse_noflush+0x34
	        vx_brelse+0x3c
	        vx_brelse_stale+0x2c
	        vx_blkinval+0x12c
	        vx_freeze_level+0x114
	        vx_freeze+0x10
	        vx_vfsfreeze+0x28
	        freeze_and_sync_fs_dev+0x38
	        lv_single_freeze_fs+0xd0
	        lv_realloclv+0x668
	        lv_ioctl+0x9bc
	        spec_ioctl+0xd4
	        vno_ioctl+0x98
	        ioctl+0x78
	        syscall+0x1a4
	        $syscallrtn+0x0

Defect Description:
	PHKL_23327:
	(SR: 8606173382   CR: JAGad42640)
	The system panics while unlocking a lock on an inode. The
	lock was freed by a thread reusing the inode while another
	thread had locked it for flushing the inode. Later when the
	flushing thread tries to unlock the freed lock a system
	panic results.

	Resolution:
	Keep a hold on the vnode while flushing the inode so that
	the inode is not reused while being flushed.

	PHKL_17526:
	(SR: 1653285320 DTS: JAGaa44494)
	A JFS file system that is in the frozen state could have
	activity generated by a 'sync' system call.  This leaves
	some buffers in the 'invalid' (B_INVAL) and delayed write
	(B_DELWRI) state.  This causes a panic.

	Running the 'lvmerge' command and sync at the same time
	on the same file system might reproduce the problem.

	Resolution:
	Protect the 'vx_delxwri_flush_inode()' call in
	'vx_delxwri_flush()' with an ACTIVE1 level so that sync
	and freeze will coordinate.

SR:
	1653285320 8606173382

Patch Files:
	/usr/conf/lib/libvxfs_base.a(vx_iflush.o)

what(1) Output:
	/usr/conf/lib/libvxfs_base.a(vx_iflush.o):
		vx_iflush.c $Date: 2001/02/06 07:55:53 $ $Revision:
			1.6.98.17 $ PATCH_10.20 (PHKL_23327)

cksum(1) Output:
	790180885 30200 /usr/conf/lib/libvxfs_base.a(vx_iflush.o)

Patch Conflicts: None

Patch Dependencies:
	s700: 10.20: PHKL_16750

Hardware Dependencies: None

Other Dependencies: None

Supersedes:
	PHKL_17526

Equivalent Patches:
	PHKL_23328:
	s800: 10.20

Patch Package Size: 90 KBytes

Installation Instructions:
	Please review all instructions and the Hewlett-Packard
	SupportLine User Guide or your Hewlett-Packard support terms
	and conditions for precautions, scope of license,
	restrictions, and, limitation of liability and warranties,
	before installing this patch.
	------------------------------------------------------------
	1. Back up your system before installing a patch.

	2. Login as root.

	3. Copy the patch to the /tmp directory.

	4. Move to the /tmp directory and unshar the patch:

		cd /tmp
		sh PHKL_23327

	5a. For a standalone system, run swinstall to install the
	    patch:

		swinstall -x autoreboot=true -x match_target=true \
			-s /tmp/PHKL_23327.depot

	By default swinstall will archive the original software in
	/var/adm/sw/patch/PHKL_23327.  If you do not wish to retain a
	copy of the original software, you can create an empty file
	named /var/adm/sw/patch/PATCH_NOSAVE.

	WARNING: If this file exists when a patch is installed, the
	         patch cannot be deinstalled.  Please be careful
		 when using this feature.

	It is recommended that you move the PHKL_23327.text file to
	/var/adm/sw/patch for future reference.

	To put this patch on a magnetic tape and install from the
	tape drive, use the command:

		dd if=/tmp/PHKL_23327.depot of=/dev/rmt/0m bs=2k

Special Installation Instructions:
	This patch depends on base patch PHKL_16750.
	For successful installation, please ensure that PHKL_16750
	is in the same depot with this patch, or PHKL_16750 is
	already installed.