Patch Name: PHKL_27346

Patch Description: s700 10.26 Buffer cache deadlock;write gets VX_ERETRY

Creation Date: 02/07/24

Post Date:  02/09/30

Hardware Platforms - OS Releases:
	s700: 10.26

Products: N/A

Filesets:
	JournalFS.VXFS-BASE-KRN

Automatic Reboot?: Yes

Status: General Release

Critical:
	Yes
	PHKL_27346: HANG

Path Name: /hp-ux_patches/s700/10.X/PHKL_27346

Symptoms:
	PHKL_27346:
	Port of 10.20 patch PHKL_26766 to TOS

	(PHKL_26766:)
	(SR: 8606225321   CR: JAGad94409)
	Applications may hang when accessing a VxFS filesystem.
	The application cannot recover. This occurs only to
	files that are mmap'ed and being written to by
	several processes at the same time.

	(PHKL_17206:)
	Writing a large mmaped region to a file on Advanced JFS
	gets return error VX_ERETRY (0xf001).

Defect Description:
	PHKL_27346:
	Port of 10.20 patch PHKL_26766 to TOS

	(PHKL_26766:)
	(SR: 8606225321   CR: JAGad94409)
	A deadlock was caused by incorrect ordering of the
	locks in VxFS code.
	Resolution:
	Reorder the locks in VxFS code to remove the deadlock.

	(PHKL_17206:)
	Advanced JFS initiates direct I/O for large buffer writes.
	When the direct I/O is unsuccessful with a return error
	VX_ERETRY, the code should retry the write using default
	I/O.  A bug in JFS write code misses the checking of
	VX_ERETRY and returns the error to the caller.
	While the symptom is seen only when Advanced JFS is
	installed, the fix is in the base JFS.

SR:
	1653285841 8606225321

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

what(1) Output:
	/usr/conf/lib/libvxfs_base.a(vx_rdwri.o):
		02/06/27 kern/vxfs/vx_rdwri.c, hpux, hpux_10.26, ic5
			gu Revision 1.11 PATCH_10.26 (PHKL_27346)

cksum(1) Output:
	2320064377 36680 /usr/conf/lib/libvxfs_base.a(vx_rdwri.o)

Patch Conflicts: None

Patch Dependencies:
	s700: 10.26: PHKL_17282

Hardware Dependencies: None

Other Dependencies: None

Supersedes: None

Equivalent Patches:
	PHKL_27347:
	s800: 10.26

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_27346

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

		swinstall -x autoreboot=true -x match_target=true \
			-s /tmp/PHKL_27346.depot

	By default swinstall will archive the original software in
	/var/adm/sw/patch/PHKL_27346.  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_27346.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_27346.depot of=/dev/rmt/0m bs=2k

Special Installation Instructions:
	This patch depends on kernel mega patch PHKL_17282.
	For successful installation, please ensure that PHKL_17282
	is in the same depot with this patch, or PHKL_17282 is
	already installed.