Patch Name: PHKL_21516

Patch Description: s700 10.20 Multiprocessor graphics and interrupts fixes

Creation Date: 00/04/24

Post Date:  00/04/28

Hardware Platforms - OS Releases:
	s700: 10.20

Products: N/A

Filesets:
	OS-Core.CORE-KRN

Automatic Reboot?: Yes

Status: General Superseded

Critical:
	Yes
	PHKL_21516: PANIC
	PHKL_19883: HANG

Path Name: /hp-ux_patches/s700/10.X/PHKL_21516

Symptoms:
	PHKL_21516:
	(SR: 8606131455   CR: JAGad00605)
	System panics with trap type 15, data page fault.  The
	stack may look like:

	resume_cleanup+0x378
	resume+0x280
	_swtch+0x138
	real_sleep+0x330
	_sleep_one+0x14
	netisr_daemon+0x194
	main+0x92c
	$vstart+0x34
	$locore+0x74

	PHKL_19883:
	On multiprocessor systems with VISUALIZE-FX graphics that
	are under a heavy I/O device interrupt load, the graphics
	subsystem may hang.

Defect Description:
	PHKL_21516:
	(SR: 8606131455   CR: JAGad00605)
	Some routines used the value of the previous thread pointer
	without verifying that it was valid, resulting in a trap
	type 15 and a system panic.

	Resolution:
	We now verify that the previous thread pointer is valid
	before dereferencing it.

	PHKL_19883:
	On multiprocessor systems, device interrrupts may be
	deferred when certain resources are in contention. Since
	VISUALIZE-FX graphics devices use interrupts for flow
	control, if their interrupts are deferred then the graphics
	card can be overrun, which will result in a graphics
	subsystem hang.
	Resoultion:
	Graphics interrupts will no longer be deferred.

SR:
	8606104451 8606131455

Patch Files:
	/usr/conf/lib/libhp-ux.a(pm_swtch.o)
	/usr/conf/lib/libhp-ux.a(syscall.o)
	/usr/conf/lib/libhp-ux.a(trap.o)

what(1) Output:
	/usr/conf/lib/libhp-ux.a(pm_swtch.o):
		pm_swtch.c    $Date: 2000/04/24 10:50:19 $ $Revision
			: 1.7.98.23 $ PATCH_10.20 (PHKL_21516)
	/usr/conf/lib/libhp-ux.a(syscall.o):
		syscall.c    $Date: 2000/04/24 11:56:22 $ $Revision:
			 1.6.98.10 $ PATCH_10.20 (PHKL_21516)
	/usr/conf/lib/libhp-ux.a(trap.o):
		trap.c    $Date: 2000/04/24 11:43:11 $ $Revision: 1.
			169.98.16 $ PATCH_10.20 (PHKL_21516)

cksum(1) Output:
	4243149544 23720 /usr/conf/lib/libhp-ux.a(pm_swtch.o)
	3916106336 6396 /usr/conf/lib/libhp-ux.a(syscall.o)
	3071457961 26380 /usr/conf/lib/libhp-ux.a(trap.o)

Patch Conflicts: None

Patch Dependencies:
	s700: 10.20: PHKL_16750

Hardware Dependencies: None

Other Dependencies: None

Supersedes:
	PHKL_19883

Equivalent Patches:
	PHKL_21517:
	s800: 10.20

Patch Package Size: 120 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_21516

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

		swinstall -x autoreboot=true -x match_target=true \
			-s /tmp/PHKL_21516.depot

	By default swinstall will archive the original software in
	/var/adm/sw/patch/PHKL_21516.  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_21516.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_21516.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.