Bug 92 - Pageout panics with NFS root + local swap
Summary: Pageout panics with NFS root + local swap
Status: Closed FIXED
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: Unspecified
Hardware: Any Any
: Normal Affects Only Me
Assignee: FreeBSD Core Team
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 1995-01-01 07:00 UTC by Gene Stark
Modified: 2007-09-13 13:53 UTC (History)
0 users

See Also:

Attachments
file.diff (441 bytes, patch)
1995-01-01 07:00 UTC, Gene Stark 		no flags Details | Diff
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Description Gene Stark 1995-01-01 07:00:01 UTC 
	When booting diskless with NFS root, but no NFS swap area
	specified (local swap desired), the system panics as soon as
	pageout is attempted.

Fix: If nd->swap_nblks is zero in nfs_mountroot(), then the system
	comes up without initializing swapdev_vp to an actual vnode pointer.
	The swap pager assumes a non-NULL value for swapdev_vp.

	The fix is to try initializing local swap if no NFS swap space
	is specified.
How-To-Repeat: 
	Boot diskless with NFS root, but no NFS swap space specified.
	Then run "man csh" or similarly large job causing pageout.
	The system will panic in the swap pager.