From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>, Ingo Molnar <mingo@elte.hu>,
Andrew Morton <akpm@linux-foundation.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Ananth N Mavinakayanahalli <ananth@in.ibm.com>,
Jim Keniston <jkenisto@linux.vnet.ibm.com>,
LKML <linux-kernel@vger.kernel.org>,
Linux-mm <linux-mm@kvack.org>, Andi Kleen <andi@firstfloor.org>,
Christoph Hellwig <hch@infradead.org>,
Steven Rostedt <rostedt@goodmis.org>,
Arnaldo Carvalho de Melo <acme@infradead.org>,
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
Thomas Gleixner <tglx@linutronix.de>,
Anton Arapov <anton@redhat.com>
Subject: Re: [RFC 0/6] uprobes: kill uprobes_srcu/uprobe_srcu_id
Date: Mon, 23 Apr 2012 12:54:45 +0530 [thread overview]
Message-ID: <20120423072445.GC8357@linux.vnet.ibm.com> (raw)
In-Reply-To: <1335165240.28150.89.camel@twins>
* Peter Zijlstra <peterz@infradead.org> [2012-04-23 09:14:00]:
> On Fri, 2012-04-20 at 20:37 +0200, Oleg Nesterov wrote:
> > Say, a user wants to probe /sbin/init only. What if init forks?
> > We should remove breakpoints from child->mm somehow.
>
> How is that hard? dup_mmap() only copies the VMAs, this doesn't actually
> copy the breakpoint. So the child doesn't have a breakpoint to be
> removed.
>
Because the pages are COWED, the breakpoint gets copied over to the
child. If we dont want the breakpoints to be not visible to the child,
then we would have to remove them explicitly based on the filter (i.e if
and if we had inserted breakpoints conditionally based on filter).
Once we add the conditional breakpoint insertion (which is tricky), we have
to support conditional breakpoint removal in the dup_mmap() thro the
uprobe_mmap hook (which I think is not that hard). Conditional removal
of breakpoints in fork path would just be an extension of the
conditional breakpoint insertion.
--
Thanks and Regards
Srikar
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2012-04-23 7:33 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-04-05 22:20 [RFC 0/6] uprobes: kill uprobes_srcu/uprobe_srcu_id Oleg Nesterov
2012-04-05 22:20 ` [PATCH 1/6] uprobes: introduce find_active_uprobe() Oleg Nesterov
2012-04-05 22:21 ` [PATCH 2/6] uprobes: introduce is_swbp_at_addr_fast() Oleg Nesterov
2012-04-16 10:08 ` Peter Zijlstra
2012-04-16 14:44 ` Oleg Nesterov
2012-04-16 14:55 ` Peter Zijlstra
2012-04-16 15:34 ` Oleg Nesterov
2012-04-17 10:08 ` Peter Zijlstra
2012-04-17 17:09 ` Oleg Nesterov
2012-04-17 19:53 ` Peter Zijlstra
2012-04-05 22:21 ` [PATCH 3/6] uprobes: teach find_active_uprobe() to provide the "is_swbp" info Oleg Nesterov
2012-04-05 22:21 ` [PATCH 4/6] uprobes: change register_for_each_vma() to take mm->mmap_sem for writing Oleg Nesterov
2012-04-05 22:22 ` [PATCH 5/6] uprobes: teach handle_swbp() to rely on "is_swbp" rather than uprobes_srcu Oleg Nesterov
2012-04-05 22:22 ` [PATCH 6/6] uprobes: kill uprobes_srcu/uprobe_srcu_id Oleg Nesterov
2012-04-14 11:16 ` [RFC 0/6] " Ingo Molnar
2012-04-16 11:31 ` Srikar Dronamraju
2012-04-16 14:41 ` Oleg Nesterov
2012-04-25 12:52 ` Srikar Dronamraju
2012-04-25 14:22 ` Oleg Nesterov
2012-04-14 13:16 ` Peter Zijlstra
2012-04-14 20:52 ` Oleg Nesterov
2012-04-15 10:51 ` Peter Zijlstra
2012-04-15 19:53 ` Oleg Nesterov
2012-04-15 21:48 ` Peter Zijlstra
2012-04-15 23:44 ` Oleg Nesterov
2012-04-16 10:16 ` Peter Zijlstra
2012-04-16 21:47 ` Oleg Nesterov
2012-04-20 10:14 ` Peter Zijlstra
2012-04-20 10:16 ` Srikar Dronamraju
2012-04-20 18:58 ` Oleg Nesterov
2012-04-20 18:37 ` Oleg Nesterov
2012-04-23 7:14 ` Peter Zijlstra
2012-04-23 7:24 ` Srikar Dronamraju [this message]
2012-04-23 7:40 ` Peter Zijlstra
2012-04-23 17:29 ` Oleg Nesterov
2012-04-23 19:18 ` Peter Zijlstra
2012-04-23 20:50 ` Oleg Nesterov
2012-04-23 21:25 ` Oleg Nesterov
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=20120423072445.GC8357@linux.vnet.ibm.com \
--to=srikar@linux.vnet.ibm.com \
--cc=acme@infradead.org \
--cc=akpm@linux-foundation.org \
--cc=ananth@in.ibm.com \
--cc=andi@firstfloor.org \
--cc=anton@redhat.com \
--cc=hch@infradead.org \
--cc=jkenisto@linux.vnet.ibm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=masami.hiramatsu.pt@hitachi.com \
--cc=mingo@elte.hu \
--cc=oleg@redhat.com \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
/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).