[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <202007161214.102F6E6@keescook>
Date: Thu, 16 Jul 2020 12:14:46 -0700
From: Kees Cook <keescook@...omium.org>
To: Peter Zijlstra <peterz@...radead.org>
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Thomas Gleixner <tglx@...utronix.de>,
Allen Pais <allen.lkml@...il.com>,
Oscar Carter <oscar.carter@....com>,
Romain Perier <romain.perier@...il.com>,
Dmitry Torokhov <dmitry.torokhov@...il.com>,
Kevin Curtis <kevin.curtis@...site.co.uk>,
"David S. Miller" <davem@...emloft.net>,
Jakub Kicinski <kuba@...nel.org>,
Harald Freudenberger <freude@...ux.ibm.com>,
Heiko Carstens <hca@...ux.ibm.com>,
Vasily Gorbik <gor@...ux.ibm.com>,
Christian Borntraeger <borntraeger@...ibm.com>,
Jiri Slaby <jslaby@...e.com>, Felipe Balbi <balbi@...nel.org>,
Jason Wessel <jason.wessel@...driver.com>,
Daniel Thompson <daniel.thompson@...aro.org>,
Douglas Anderson <dianders@...omium.org>,
Mitchell Blank Jr <mitch@...oth.com>,
Julian Wiedmann <jwi@...ux.ibm.com>,
Karsten Graul <kgraul@...ux.ibm.com>,
Ursula Braun <ubraun@...ux.ibm.com>,
Jaroslav Kysela <perex@...ex.cz>, Takashi Iwai <tiwai@...e.com>,
Christian Gromm <christian.gromm@...rochip.com>,
Nishka Dasgupta <nishkadg.linux@...il.com>,
Masahiro Yamada <masahiroy@...nel.org>,
Stephen Boyd <swboyd@...omium.org>,
"Matthew Wilcox (Oracle)" <willy@...radead.org>,
Wambui Karuga <wambui.karugax@...il.com>,
Guenter Roeck <linux@...ck-us.net>,
Chris Packham <chris.packham@...iedtelesis.co.nz>,
Kyungtae Kim <kt0755@...il.com>,
Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@...ux.intel.com>,
Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
"Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
Jonathan Corbet <corbet@....net>, Will Deacon <will@...nel.org>,
linux-input@...r.kernel.org, linux-kernel@...r.kernel.org,
netdev@...r.kernel.org, linux-s390@...r.kernel.org,
devel@...verdev.osuosl.org, linux-usb@...r.kernel.org,
kgdb-bugreport@...ts.sourceforge.net, alsa-devel@...a-project.org,
kernel-hardening@...ts.openwall.com
Subject: Re: [PATCH 0/3] Modernize tasklet callback API
On Thu, Jul 16, 2020 at 09:57:18AM +0200, Peter Zijlstra wrote:
> On Wed, Jul 15, 2020 at 08:08:44PM -0700, Kees Cook wrote:
> > Hi,
> >
> > This is the infrastructure changes to prepare the tasklet API for
> > conversion to passing the tasklet struct as the callback argument instead
> > of an arbitrary unsigned long. The first patch details why this is useful
> > (it's the same rationale as the timer_struct changes from a bit ago:
> > less abuse during memory corruption attacks, more in line with existing
> > ways of doing things in the kernel, save a little space in struct,
> > etc). Notably, the existing tasklet API use is much less messy, so there
> > is less to clean up.
>
> I would _MUCH_ rather see tasklets go the way of the dodo, esp. given
> that:
>
> > drivers/input/keyboard/omap-keypad.c | 2 +-
> > drivers/input/serio/hil_mlc.c | 2 +-
> > drivers/net/wan/farsync.c | 4 +--
> > drivers/s390/crypto/ap_bus.c | 2 +-
> > drivers/staging/most/dim2/dim2.c | 2 +-
> > drivers/staging/octeon/ethernet-tx.c | 2 +-
> > drivers/tty/vt/keyboard.c | 2 +-
> > drivers/usb/gadget/udc/snps_udc_core.c | 6 ++---
> > drivers/usb/host/fhci-sched.c | 2 +-
> > include/linux/interrupt.h | 37 ++++++++++++++++++++++----
> > kernel/backtracetest.c | 2 +-
> > kernel/debug/debug_core.c | 2 +-
> > kernel/irq/resend.c | 2 +-
> > kernel/softirq.c | 18 ++++++++++++-
> > net/atm/pppoatm.c | 2 +-
> > net/iucv/iucv.c | 2 +-
> > sound/drivers/pcsp/pcsp_lib.c | 2 +-
> > 17 files changed, 66 insertions(+), 25 deletions(-)
>
> there appear to be hardly any users left.. Can't we stage an extinction
> event here instead?
Oh, I wish, but no. That's just the ones using DECLARE_TASKLET. There
are hundred(s?) more (see the referenced tree).
--
Kees Cook
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
