Don't trace threads that have interrupts disabled.
ClosedPublic
Actions

Authored by markj on Jul 31 2017, 1:12 AM.

Tags

None

Referenced Files

	Unknown Object (File)
	Mon, Nov 18, 3:04 AM

	Unknown Object (File)
	Mon, Nov 18, 12:18 AM

	Unknown Object (File)
	Sun, Nov 17, 6:32 PM

	Unknown Object (File)
	Sun, Nov 17, 5:44 PM

	Unknown Object (File)
	Sun, Nov 17, 2:06 PM

	Unknown Object (File)
	Sun, Nov 17, 1:57 PM

	Unknown Object (File)
	Sun, Nov 17, 12:49 PM

	Unknown Object (File)
	Mon, Oct 28, 4:58 PM

View All 45 Files

Subscribers

None

Details

Reviewers

jhb
kib

Commits

rS321803: Don't trace running threads that have interrupts disabled.

Summary

The register file of such a thread is in an indeterminate state, so we
shouldn't assume that the frame pointer is valid. In particular, we may
be in the middle of restoring host registers after a vmexit.

Diff Detail

Repository

rS FreeBSD src repository - subversion

Lint

Lint Not Applicable

Unit

Tests Not Applicable

Event Timeline

markj created this revision.Jul 31 2017, 1:12 AM

Harbormaster completed remote builds in B10756: Diff 31361.Jul 31 2017, 1:12 AM

markj edited the summary of this revision. (Show Details)Jul 31 2017, 1:13 AM

markj added reviewers: jhb, kib.

This is fine, but then you do not need NMI.

This revision is now accepted and ready to land.Jul 31 2017, 7:20 AM

In D11787#244481, @kib wrote:

This is fine, but then you do not need NMI.

We use an NMI to avoid to avoid a deadlock: the case where the target thread holds a spinlock and thus has interrupts disabled, and is blocked on the thread lock held by the stack_save_td_running() caller.

Closed by commit rS321803: Don't trace running threads that have interrupts disabled. (authored by markj). · Explain WhyJul 31 2017, 5:58 PM

This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

Path

Size

head/

sys/

x86/

stack_machdep.c

7 lines

Diff 31383

View Options

head/sys/x86/x86/stack_machdep.c

Don't trace threads that have interrupts disabled.ClosedPublicActions