linux-kernel - [RFC/PATCH] perf: Expand definition of sysfs format attribute

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1362370865-4437-1-git-send-email-michael@ellerman.id.au>
Date:	Mon,  4 Mar 2013 15:21:05 +1100
From:	Michael Ellerman <michael@...erman.id.au>
To:	acme@...radead.org
Cc:	peterz@...radead.org, jolsa@...hat.com,
	<linux-kernel@...r.kernel.org>, linux-doc@...r.kernel.org,
	rob@...dley.net
Subject: [RFC/PATCH] perf: Expand definition of sysfs format attribute

Make it explicit that the format attributes may define overlapping bit
ranges. Unfortunately this was left unspecified originally, and all the
examples show non-overlapping ranges. I don't believe this is an ABI
change, as we are defining something that was previously undefined, but
others may disagree.

The POWER8 PMU would like to define overlapping ranges, as bit ranges in
the event code have different meanings for certain events. It will also
allow us to define an overarching "event" field, that encompasses all
others.

As far as I can see perf is comfortable with this change, however I am
not sure if there are any other users of the interface.

Signed-off-by: Michael Ellerman <michael@...erman.id.au>
---
 Documentation/ABI/testing/sysfs-bus-event_source-devices-format |    6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-event_source-devices-format b/Documentation/ABI/testing/sysfs-bus-event_source-devices-format
index 079afc7..77f47ff 100644
--- a/Documentation/ABI/testing/sysfs-bus-event_source-devices-format
+++ b/Documentation/ABI/testing/sysfs-bus-event_source-devices-format
@@ -9,6 +9,12 @@ Description:
 		we want to export, so that userspace can deal with sane
 		name/value pairs.
 
+		Userspace must be prepared for the possibility that attributes
+		define overlapping bit ranges. For example:
+			attr1 = 'config:0-23'
+			attr2 = 'config:0-7'
+			attr3 = 'config:12-35'
+
 		Example: 'config1:1,6-10,44'
 		Defines contents of attribute that occupies bits 1,6-10,44 of
 		perf_event_attr::config1.
-- 
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/