Bug 2685

Summary:	need to skip probes on insufficient stack
Product:	systemtap	Reporter:	Frank Ch. Eigler <fche>
Component:	translator	Assignee:	Frank Ch. Eigler <fche>
Status:	RESOLVED FIXED
Severity:	normal
Priority:	P2
Version:	unspecified
Target Milestone:	---
Host:		Target:
Build:		Last reconfirmed:

Description Frank Ch. Eigler 2006-05-22 18:19:41 UTC

Similarly to bug #2185, because we don't have a separate stack for kprobe
handling (bug #931), we may have stack exhaustion problems in ordinary usage
without reentrancy.  We go out of our way to minimize stack usage, but we need to
- estimate or measure stack usage of a worst-case scenario (kprobes handler,
deeply nested systemtap expression, calling into the most complex runtime routine)
- add code to the probe entry functions to check for available stack space, and
punt (skip probe) if it's not sufficient

Comment 1 Frank Ch. Eigler 2006-11-26 23:28:56 UTC

patch committed.  The default MINSTACKSPACE may need to be tuned in the future.