Bug 14584 - Infinite loop in assert_no_pending_aio()
Summary: Infinite loop in assert_no_pending_aio()
Status: RESOLVED DUPLICATE of bug 14515
Alias: None
Product: Samba 4.1 and newer
Classification: Unclassified
Component: File services (show other bugs)
Version: 4.12.9
Hardware: x86 Linux
: P5 major (vote)
Target Milestone: ---
Assignee: Samba QA Contact
QA Contact: Samba QA Contact
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2020-11-27 07:20 UTC by Peter Urbanec
Modified: 2020-11-27 14:04 UTC (History)
1 user (show)

See Also:

Attachments
gdb backtrace (10.51 KB, text/plain)
2020-11-27 07:24 UTC, Peter Urbanec 		no flags Details
View All Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.
Description Peter Urbanec 2020-11-27 07:20:01 UTC 
I'm seeing a situation where a Samba server will have a number of processes using up 100% CPU and not make any system calls. I have not managed to reproduce a test case that will trigger this condition.

I built a version of samba with debug symbols and attached gdb. After a bit of investigation, I think I found the reason in source3/smbd/close.c

The function assert_no_pending_aio() is stuck in an infinite loop at line 669.

	while (fsp->num_aio_requests != 0) {
		TALLOC_FREE(fsp->aio_requests[0]);
	}

The code above only frees the request, but never decrements the counter, thus the loop never terminates.
Comment 1 Peter Urbanec 2020-11-27 07:24:35 UTC 
Created attachment 16349 [details]
gdb backtrace

Attached is a full backtrace from gdb.
Comment 2 Stefan Metzmacher 2020-11-27 14:04:55 UTC 

*** This bug has been marked as a duplicate of bug 14515 ***