From f3fddaf60b9b983b82cd11e8087e7c8a3903ee14 Mon Sep 17 00:00:00 2001 From: "Daniel P. Berrange" Date: Wed, 26 Apr 2017 16:39:00 +0100 Subject: [PATCH] trace: disallow more than 10 arguments per trace event MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The UST trace backend can only cope with upto 10 arguments. To ensure we don't exceed the limit when UST is not compiled in, disallow more than 10 arguments upfront. This prevents the case where: commit 0fc8aec7de64f2bf83a274a2a38b938ce03425d2 Author: Zhang Chen Date: Tue Apr 18 10:20:20 2017 +0800 COLO-compare: Optimize tcp compare trace event Optimize two trace events as one, adjust print format make it easy to read. rename trace_colo_compare_pkt_info_src/dst to trace_colo_compare_tcp_info. regressed the fix done in commit 2dfe5113b11ce0ddb08176ebb54ab7ac4104b413 Author: Alex Bennée Date: Fri Oct 28 14:25:59 2016 +0100 net: split colo_compare_pkt_info into two trace events It seems there is a limit to the number of arguments a UST trace event can take and at 11 the previous trace command broke the build. Split the trace into a src pkt and dst pkt trace to fix this. Signed-off-by: Alex Bennée Message-id: 20161028132559.8324-1-alex.bennee@linaro.org Reviewed-by: Peter Maydell Signed-off-by: Peter Maydell Now we get an immediate fail even when UST is disabled: GEN net/trace.h Traceback (most recent call last): File "/home/berrange/src/virt/qemu/scripts/tracetool.py", line 154, in main(sys.argv) File "/home/berrange/src/virt/qemu/scripts/tracetool.py", line 145, in main events.extend(tracetool.read_events(fh)) File "/home/berrange/src/virt/qemu/scripts/tracetool/__init__.py", line 307, in read_events event = Event.build(line) File "/home/berrange/src/virt/qemu/scripts/tracetool/__init__.py", line 244, in build event = Event(name, props, fmt, args) File "/home/berrange/src/virt/qemu/scripts/tracetool/__init__.py", line 196, in __init__ "argument count" % name) ValueError: Event 'colo_compare_tcp_info' has more than maximum permitted argument count Makefile:96: recipe for target 'net/trace.h-timestamp' failed Signed-off-by: Daniel P. Berrange Reviewed-by: Eric Blake Message-id: 20170426153900.21066-1-berrange@redhat.com Signed-off-by: Stefan Hajnoczi --- scripts/tracetool/__init__.py | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/scripts/tracetool/__init__.py b/scripts/tracetool/__init__.py index 365446fa53..1ffbc1dc40 100644 --- a/scripts/tracetool/__init__.py +++ b/scripts/tracetool/__init__.py @@ -191,6 +191,10 @@ class Event(object): self.event_trans = event_trans self.event_exec = event_exec + if len(args) > 10: + raise ValueError("Event '%s' has more than maximum permitted " + "argument count" % name) + if orig is None: self.original = weakref.ref(self) else: