From: Steven Rostedt <rostedt@goodmis.org>
To: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Scott Wood <scottwood@freescale.com>,
Eran Liberty <liberty@extricom.com>,
linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org,
Steven Rostedt <srostedt@redhat.com>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Subject: Re: ftrace introduces instability into kernel 2.6.27(-rc2,-rc3)
Date: Mon, 18 Aug 2008 23:32:08 -0400 (EDT) [thread overview]
Message-ID: <alpine.DEB.1.10.0808182329220.13401@gandalf.stny.rr.com> (raw)
In-Reply-To: <20080819024707.GA22659@Krystal>
On Mon, 18 Aug 2008, Mathieu Desnoyers wrote:
> * Steven Rostedt (rostedt@goodmis.org) wrote:
> >
> > On Tue, 19 Aug 2008, Benjamin Herrenschmidt wrote:
> >
> > >
> > > > Hmm, this was originally copied from x86, where we did a cmpxchg, but that
> > > > is probably not needed since all of this is done in kstop_machine. Also,
> > > > only the "get" is needed. If we don't fault there, we wont fault on the
> > > > put (unless we have permissions wrong, and that would be a bug).
> > >
> > > Would it ? How do we make sure the kernel text is mapped writeable ?
> >
> > We map it writeable if FTRACE is enabled.
> >
>
> Argh. See text_poke(). It's there exactly for this purpose on x86.
Ouch, I just did. text_poke is quite heavy. It would be interesting to see
that performed on 20,000 locations at one time. I could play with it, but
I'm a bit nervous.
-- Steve
next prev parent reply other threads:[~2008-08-19 3:32 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-06-18 14:18 2.6.24-rc4: pci_remove_bus_device() => pci_scan_child_bus() => pci_bus_add_devices bug? Eran Liberty
2008-07-20 10:31 ` [PATCH 2.6.24-rc4] PCI: refuse to re-add a device to a bus upon pci_scan_child_bus() Eran Liberty
2008-07-20 16:48 ` Eran Liberty
2008-07-21 19:18 ` [PATCH 2.6.26] " Eran Liberty
2008-07-21 19:49 ` Matthew Wilcox
2008-07-22 8:21 ` eran liberty
2008-07-22 11:49 ` Matthew Wilcox
2008-07-22 13:08 ` Eran Liberty
2008-07-22 13:14 ` Eran Liberty
2008-07-22 14:13 ` Matthew Wilcox
2008-07-22 15:25 ` Eran Liberty
2008-07-22 16:52 ` Matthew Wilcox
2008-07-22 17:41 ` Eran Liberty
2008-07-22 18:11 ` Matthew Wilcox
2008-07-23 18:31 ` Eran Liberty
2008-07-27 11:01 ` Eran Liberty
2008-07-27 15:08 ` Matthew Wilcox
2008-08-18 8:08 ` ftrace introduces instability into kernel 2.6.27(-rc2,-rc3) Eran Liberty
2008-08-18 15:07 ` Steven Rostedt
2008-08-18 15:47 ` Mathieu Desnoyers
2008-08-18 16:12 ` Steven Rostedt
2008-08-18 17:04 ` Mathieu Desnoyers
2008-08-18 17:21 ` Scott Wood
2008-08-18 18:27 ` Steven Rostedt
2008-08-18 18:29 ` Scott Wood
2008-08-19 1:53 ` Benjamin Herrenschmidt
2008-08-19 2:28 ` Steven Rostedt
2008-08-19 2:39 ` Benjamin Herrenschmidt
2008-08-19 2:41 ` Steven Rostedt
2008-08-19 2:47 ` Mathieu Desnoyers
2008-08-19 3:32 ` Steven Rostedt [this message]
2008-08-19 3:36 ` Mathieu Desnoyers
2008-08-19 4:00 ` Steven Rostedt
2008-08-19 16:47 ` Steven Rostedt
2008-08-19 17:34 ` Mathieu Desnoyers
2008-08-19 21:08 ` Steven Rostedt
2008-08-20 9:40 ` Nick Piggin
2008-08-19 21:47 ` Benjamin Herrenschmidt
2008-08-19 23:58 ` Jeremy Fitzhardinge
2008-08-20 1:17 ` Benjamin Herrenschmidt
2008-08-19 2:56 ` Benjamin Herrenschmidt
2008-08-19 3:12 ` Steven Rostedt
2008-08-19 4:17 ` Benjamin Herrenschmidt
2008-08-20 7:18 ` Benjamin Herrenschmidt
2008-08-20 13:14 ` Steven Rostedt
2008-08-20 13:19 ` Steven Rostedt
2008-08-20 13:36 ` Eran Liberty
2008-08-20 13:43 ` Steven Rostedt
2008-08-20 14:02 ` Eran Liberty
2008-08-20 14:55 ` Jon Smirl
2008-08-20 15:23 ` Steven Rostedt
2008-08-20 18:23 ` Eran Liberty
2008-08-20 18:33 ` Steven Rostedt
2008-08-20 15:27 ` Steven Rostedt
2008-08-20 21:37 ` Benjamin Herrenschmidt
2008-08-20 14:16 ` Josh Boyer
2008-08-20 14:22 ` Steven Rostedt
2008-08-20 14:50 ` Josh Boyer
2008-09-15 16:30 ` [PATCH 2.6.26] SERIAL DRIVER: Handle Multiple consecutive sysrq from the serial Eran Liberty
2008-09-17 23:46 ` Andrew Morton
2008-09-18 6:58 ` Eran Liberty
2008-08-20 21:36 ` ftrace introduces instability into kernel 2.6.27(-rc2,-rc3) Benjamin Herrenschmidt
2008-08-20 21:44 ` Steven Rostedt
2008-08-18 18:47 ` Steven Rostedt
2008-08-18 18:56 ` Scott Wood
2008-08-18 19:28 ` Steven Rostedt
2008-08-18 18:25 ` Eran Liberty
2008-08-18 18:41 ` Mathieu Desnoyers
2008-08-19 1:54 ` Benjamin Herrenschmidt
2008-08-19 9:56 ` Eran Liberty
2008-08-19 13:02 ` Mathieu Desnoyers
2008-08-19 21:46 ` Benjamin Herrenschmidt
2008-08-18 18:50 ` Steven Rostedt
2008-08-19 12:09 ` Eran Liberty
2008-08-19 13:05 ` Mathieu Desnoyers
2008-08-19 14:21 ` Eran Liberty
2008-08-19 14:42 ` Mathieu Desnoyers
2008-08-19 20:15 ` Steven Rostedt
2008-08-20 11:18 ` Eran Liberty
2008-08-20 13:12 ` Steven Rostedt
2008-08-19 1:51 ` Benjamin Herrenschmidt
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