Patch Name: PHKL_23225

Patch Description: s700_800 11.11 Fix for dqput() data page fault panic

Creation Date: 01/02/01

Post Date:  01/05/01

Hardware Platforms - OS Releases:
	s700: 11.11
	s800: 11.11

Products: N/A

Filesets:
	OS-Core.CORE2-KRN,fr=B.11.11,fa=HP-UX_B.11.11_32,v=HP
	OS-Core.CORE2-KRN,fr=B.11.11,fa=HP-UX_B.11.11_64,v=HP

Automatic Reboot?: Yes

Status: General Release

Critical:
	Yes
	PHKL_23225: PANIC

Category Tags:
	defect_repair general_release critical panic

Path Name: /hp-ux_patches/s700_800/11.X/PHKL_23225

Symptoms:
	PHKL_23225:
	( SR:8606167622 CR:JAGad36908 )
	Data Page fault due to a race between mkdir( ) and unmount
	on a filesystem with quotas. The stack trace for this race
	condition looks like:
	            stack trace for event 0
	            crash event was a panic
	            panic+0x14
	            dqput+0x38
	            dqrele+0xb8
	            ieget+0x1b4
	            in_get+0x30
	            iget+0x18
	            ialloc+0x114
	            dirmakeinode+0xc8
	            direnter+0x1e4
	            ufs_mkdir+0x4c
	            vns_create+0x168
	            vn_create+0xcc
	            mkdir+0x80
	            syscall+0x480
	           $syscallrtn+0x0

Defect Description:
	PHKL_23225:
	( SR:8606167622 CR:JAGad36908 )
	This is due to a race between two threads one running
	mkdir( ) and the other umount( ) at the same time, on
	a filesystem with quotas on. umount( ) grabs the
	filesystem semaphore, but has not yet gotten rid of
	the quota (dquot) structure. At this time mkdir( )
	seeing the dquot structure still valid tries to execute
	dqrele(), but blocks or sleeps because the filesystem
	semaphore is held by umount( ). umount( ) finishes what
	it is doing, including getting rid of the dquot
	structure. It then releases the filesystem semaphore.
	dqrele() now gets the filesystem semaphore and continues.
	It dosen't check again to see if the dquot structure
	is still valid. At this point it is trying to release a
	dquot for a filesystem that has already been unmounted,
	and thus panics.

	Resolution:
	When releasing the quota (dquot) structure for
	an inode pointer verify that  the dquot structure is
	valid both before and after acquiring the
	filesystem semaphore.

SR:
	8606167622

Patch Files:
	
	OS-Core.CORE2-KRN,fr=B.11.11,fa=HP-UX_B.11.11_32,v=HP:
	/usr/conf/lib/libfs.a(quota_ufs.o)
	/usr/conf/lib/libufs.a(ufs_inode.o)

	OS-Core.CORE2-KRN,fr=B.11.11,fa=HP-UX_B.11.11_64,v=HP:
	/usr/conf/lib/libfs.a(quota_ufs.o)
	/usr/conf/lib/libufs.a(ufs_inode.o)

what(1) Output:
	
	OS-Core.CORE2-KRN,fr=B.11.11,fa=HP-UX_B.11.11_32,v=HP:
	/usr/conf/lib/libfs.a(quota_ufs.o):
		quota_ufs.c $Date: 2001/01/25 13:28:39 $Revision: r1
			1.11/1 PATCH_11.11 (PHKL_23225)
	/usr/conf/lib/libufs.a(ufs_inode.o):
		ufs_inode.c $Date: 2001/01/25 13:31:27 $Revision: r1
			1.11/1 PATCH_11.11 (PHKL_23225)

	OS-Core.CORE2-KRN,fr=B.11.11,fa=HP-UX_B.11.11_64,v=HP:
	/usr/conf/lib/libfs.a(quota_ufs.o):
		quota_ufs.c $Date: 2001/01/25 13:28:39 $Revision: r1
			1.11/1 PATCH_11.11 (PHKL_23225)
	/usr/conf/lib/libufs.a(ufs_inode.o):
		ufs_inode.c $Date: 2001/01/25 13:31:27 $Revision: r1
			1.11/1 PATCH_11.11 (PHKL_23225)

cksum(1) Output:
	
	OS-Core.CORE2-KRN,fr=B.11.11,fa=HP-UX_B.11.11_32,v=HP:
	852367057 6872 /usr/conf/lib/libfs.a(quota_ufs.o)
	2948363372 32432 /usr/conf/lib/libufs.a(ufs_inode.o)

	OS-Core.CORE2-KRN,fr=B.11.11,fa=HP-UX_B.11.11_64,v=HP:
	3348717254 15928 /usr/conf/lib/libfs.a(quota_ufs.o)
	3176118795 75248 /usr/conf/lib/libufs.a(ufs_inode.o)

Patch Conflicts: None

Patch Dependencies: None

Hardware Dependencies: None

Other Dependencies: None

Supersedes: None

Equivalent Patches:
	PHKL_22635:
	s700: 11.00
	s800: 11.00

Patch Package Size: 150 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_23225

	5. Run swinstall to install the patch:

		swinstall -x autoreboot=true -x patch_match_target=true \
			  -s /tmp/PHKL_23225.depot

	By default swinstall will archive the original software in 
	/var/adm/sw/save/PHKL_23225.  If you do not wish to retain a
	copy of the original software, use the patch_save_files option:

		swinstall -x autoreboot=true -x patch_match_target=true \
			  -x patch_save_files=false -s /tmp/PHKL_23225.depot

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

	For future reference, the contents of the PHKL_23225.text file is 
	available in the product readme:

		swlist -l product -a readme -d @ /tmp/PHKL_23225.depot

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

		dd if=/tmp/PHKL_23225.depot of=/dev/rmt/0m bs=2k

Special Installation Instructions: None