Patch Name: PHKL_19889

Patch Description: s700 10.20 fix vfork(2)-induced panic under memory pressure

Creation Date: 99/09/13

Post Date:  99/09/17

Hardware Platforms - OS Releases:
	s700: 10.20

Products: N/A

Filesets:
	OS-Core.CORE-KRN

Automatic Reboot?: Yes

Status: General Release

Critical:
	Yes
	PHKL_19889: PANIC

Path Name: /hp-ux_patches/s700/10.X/PHKL_19889

Symptoms:
	PHKL_19889:
	Under severe memory pressure, system could panic with what
	appeared to a bad pointer in vasusage().

Defect Description:
	PHKL_19889:
	This was an MP race between vfork(2) and vmtotal().  If the
	system is out of RAM, vfork(2) can fail, and there was a
	small chance that a corrupt p_vas could result.
	Resolution:
	Acquire/release spinlocks around the critical section in
	vfork(2).

SR:
	1653306100

Patch Files:
	/usr/conf/lib/libhp-ux.a(pm_procdup.o)

what(1) Output:
	/usr/conf/lib/libhp-ux.a(pm_procdup.o):
		pm_procdup.c $Date: 99/09/13 15:37:12 $ $Revision: 1
			.11.98.15 $ PATCH_10.20 (PHKL_19889)

cksum(1) Output:
	605701385 6808 /usr/conf/lib/libhp-ux.a(pm_procdup.o)

Patch Conflicts: None

Patch Dependencies:
	s700: 10.20: PHKL_16750

Hardware Dependencies: None

Other Dependencies: None

Supersedes: None

Equivalent Patches:
	PHKL_19890:
	s800: 10.20

Patch Package Size: 60 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_19889

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

		swinstall -x autoreboot=true -x match_target=true \
			-s /tmp/PHKL_19889.depot

	By default swinstall will archive the original software in
	/var/adm/sw/patch/PHKL_19889.  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_19889.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_19889.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.