From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>,
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
Namhyung Kim <namhyung@kernel.org>,
Tom Zanussi <tom.zanussi@linux.intel.com>,
"zhangwei(Jovi)" <jovi.zhangwei@huawei.com>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/4] tracing/uprobes: Revert "Support mix of ftrace and perf"
Date: Mon, 30 Jun 2014 22:26:26 +0530 [thread overview]
Message-ID: <20140630165626.GA5619@linux.vnet.ibm.com> (raw)
In-Reply-To: <20140627170136.GA18319@redhat.com>
* Oleg Nesterov <oleg@redhat.com> [2014-06-27 19:01:36]:
> This reverts commit 43fe98913c9f67e3b523615ee3316f9520a623e0.
>
> This patch is very wrong. Firstly, this change leads to unbalanced
> uprobe_unregister(). Just for example,
>
> # perf probe -x /lib/libc.so.6 syscall
> # echo 1 >> /sys/kernel/debug/tracing/events/probe_libc/enable
> # perf record -e probe_libc:syscall whatever
>
> after that uprobe is dead (unregistered) but the user of ftrace/perf
> can't know this, and it looks as if nobody hits this probe.
>
> This would be easy to fix, but there are other reasons why it is not
> simple to mix ftrace and perf. If nothing else, they can't share the
> same ->consumer.filter. This is fixable too, but probably we need to
> fix the poorly designed uprobe_register() interface first. At least
> "register" and "apply" should be clearly separated.
>
> Cc: stable@vger.kernel.org # v3.14
> Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
--
Thanks and Regards
Srikar Dronamraju
next prev parent reply other threads:[~2014-06-30 16:56 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-27 17:01 [PATCH 0/4] tracing/uprobes fixes Oleg Nesterov
2014-06-27 17:01 ` [PATCH 1/4] tracing/uprobes: Revert "Support mix of ftrace and perf" Oleg Nesterov
2014-06-30 5:49 ` Namhyung Kim
2014-06-30 18:48 ` Oleg Nesterov
2014-07-01 19:31 ` probe_event_disable()->synchronize_sched() (Was: tracing/uprobes: Revert "Support mix of ftrace and perf") Oleg Nesterov
2014-07-03 0:54 ` probe_event_disable()->synchronize_sched() Namhyung Kim
2014-07-03 15:41 ` probe_event_disable()->synchronize_sched() Oleg Nesterov
2014-07-03 5:35 ` probe_event_disable()->synchronize_sched() (Was: tracing/uprobes: Revert "Support mix of ftrace and perf") Masami Hiramatsu
2014-07-03 5:46 ` Masami Hiramatsu
2014-07-03 7:44 ` probe_event_disable()->synchronize_sched() Namhyung Kim
2014-07-04 1:00 ` probe_event_disable()->synchronize_sched() Masami Hiramatsu
2014-07-04 8:01 ` probe_event_disable()->synchronize_sched() Namhyung Kim
2014-07-03 16:22 ` probe_event_disable()->synchronize_sched() (Was: tracing/uprobes: Revert "Support mix of ftrace and perf") Oleg Nesterov
2014-07-03 17:01 ` __trace_remove_event_dirs() leaks file->filter ? (Was: probe_event_disable()->synchronize_sched()) Oleg Nesterov
2014-07-04 5:21 ` Masami Hiramatsu
2014-07-04 19:38 ` Oleg Nesterov
2014-07-04 4:46 ` probe_event_disable()->synchronize_sched() (Was: tracing/uprobes: Revert "Support mix of ftrace and perf") Masami Hiramatsu
2014-06-30 11:52 ` [PATCH 1/4] tracing/uprobes: Revert "Support mix of ftrace and perf" Masami Hiramatsu
2014-06-30 16:56 ` Srikar Dronamraju [this message]
2014-06-27 17:01 ` [PATCH 2/4] uprobes: Change unregister/apply to WARN() if uprobe/consumer is gone Oleg Nesterov
2014-06-30 5:50 ` Namhyung Kim
2014-06-30 16:57 ` Srikar Dronamraju
2014-06-27 17:01 ` [PATCH 3/4] tracing/uprobes: Kill the bogus UPROBE_HANDLER_REMOVE code in uprobe_dispatcher() Oleg Nesterov
2014-06-30 6:03 ` Namhyung Kim
2014-06-30 16:57 ` Srikar Dronamraju
2014-06-27 17:01 ` [PATCH 4/4] tracing/uprobes: Fix the usage of uprobe_buffer_enable() in probe_event_enable() Oleg Nesterov
2014-06-30 6:18 ` Namhyung Kim
2014-06-30 11:49 ` Masami Hiramatsu
2014-06-30 17:04 ` Srikar Dronamraju
2014-06-30 17:21 ` Steven Rostedt
2014-06-30 17:58 ` Oleg Nesterov
2014-06-30 18:22 ` Steven Rostedt
2014-06-30 17:50 ` Oleg Nesterov
2014-06-30 18:01 ` Steven Rostedt
2014-06-30 13:28 ` [PATCH 0/4] tracing/uprobes fixes Steven Rostedt
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20140630165626.GA5619@linux.vnet.ibm.com \
--to=srikar@linux.vnet.ibm.com \
--cc=jovi.zhangwei@huawei.com \
--cc=linux-kernel@vger.kernel.org \
--cc=masami.hiramatsu.pt@hitachi.com \
--cc=namhyung@kernel.org \
--cc=oleg@redhat.com \
--cc=rostedt@goodmis.org \
--cc=tom.zanussi@linux.intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).