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-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <ZtnP6CK-Zd8SJAgY@smile.fi.intel.com>
Date: Thu, 5 Sep 2024 18:36:08 +0300
From: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To: Uros Bizjak <ubizjak@...il.com>
Cc: linux-kernel@...r.kernel.org, Dave Hansen <dave.hansen@...ux.intel.com>,
	Andy Lutomirski <luto@...nel.org>,
	Peter Zijlstra <peterz@...radead.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
	x86@...nel.org, "H. Peter Anvin" <hpa@...or.com>,
	Jani Nikula <jani.nikula@...ux.intel.com>,
	Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
	Rodrigo Vivi <rodrigo.vivi@...el.com>,
	Tvrtko Ursulin <tursulin@...ulin.net>,
	David Airlie <airlied@...il.com>, Daniel Vetter <daniel@...ll.ch>,
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
	Maxime Ripard <mripard@...nel.org>,
	Thomas Zimmermann <tzimmermann@...e.de>,
	Hans Verkuil <hverkuil@...all.nl>,
	Mauro Carvalho Chehab <mchehab@...nel.org>,
	Miquel Raynal <miquel.raynal@...tlin.com>,
	Richard Weinberger <richard@....at>,
	Vignesh Raghavendra <vigneshr@...com>,
	Eric Biggers <ebiggers@...nel.org>,
	"Theodore Y. Ts'o" <tytso@....edu>,
	Jaegeuk Kim <jaegeuk@...nel.org>,
	"Jason A. Donenfeld" <Jason@...c4.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Hannes Reinecke <hare@...e.de>,
	"James E.J. Bottomley" <James.Bottomley@...senpartnership.com>,
	"Martin K. Petersen" <martin.petersen@...cle.com>,
	Alexei Starovoitov <ast@...nel.org>,
	Daniel Borkmann <daniel@...earbox.net>,
	John Fastabend <john.fastabend@...il.com>,
	Andrii Nakryiko <andrii@...nel.org>,
	Martin KaFai Lau <martin.lau@...ux.dev>,
	Eduard Zingerman <eddyz87@...il.com>, Song Liu <song@...nel.org>,
	Yonghong Song <yonghong.song@...ux.dev>,
	KP Singh <kpsingh@...nel.org>, Stanislav Fomichev <sdf@...ichev.me>,
	Hao Luo <haoluo@...gle.com>, Jiri Olsa <jolsa@...nel.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Brendan Higgins <brendan.higgins@...ux.dev>,
	David Gow <davidgow@...gle.com>, Rae Moar <rmoar@...gle.com>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>,
	Jiri Pirko <jiri@...nulli.us>, Petr Mladek <pmladek@...e.com>,
	Steven Rostedt <rostedt@...dmis.org>,
	Rasmus Villemoes <linux@...musvillemoes.dk>,
	Sergey Senozhatsky <senozhatsky@...omium.org>,
	Stephen Hemminger <stephen@...workplumber.org>,
	Jamal Hadi Salim <jhs@...atatu.com>,
	Cong Wang <xiyou.wangcong@...il.com>,
	Kent Overstreet <kent.overstreet@...ux.dev>,
	intel-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
	linux-media@...r.kernel.org, linux-mtd@...ts.infradead.org,
	linux-fscrypt@...r.kernel.org, linux-scsi@...r.kernel.org,
	bpf@...r.kernel.org, linux-kselftest@...r.kernel.org,
	kunit-dev@...glegroups.com
Subject: Re: [PATCH 00/18] random: Include <linux/percpu.h> and resolve
 circular include dependency

On Thu, Sep 05, 2024 at 03:03:24PM +0200, Uros Bizjak wrote:
> On Thu, Sep 5, 2024 at 2:41 PM Andy Shevchenko
> <andriy.shevchenko@...ux.intel.com> wrote:
> >
> > On Thu, Sep 05, 2024 at 02:17:08PM +0200, Uros Bizjak wrote:
> > > There were several attempts to resolve circular include dependency
> > > after the addition of percpu.h: 1c9df907da83 ("random: fix circular
> > > include dependency on arm64 after addition of percpu.h"), c0842fbc1b18
> > > ("random32: move the pseudo-random 32-bit definitions to prandom.h") and
> > > finally d9f29deb7fe8 ("prandom: Remove unused include") that completely
> > > removes inclusion of <linux/percpu.h>.
> > >
> > > Due to legacy reasons, <linux/random.h> includes <linux/prandom.h>, but
> > > with the commit entry remark:
> > >
> > > --quote--
> > > A further cleanup step would be to remove this from <linux/random.h>
> > > entirely, and make people who use the prandom infrastructure include
> > > just the new header file.  That's a bit of a churn patch, but grepping
> > > for "prandom_" and "next_pseudo_random32" "struct rnd_state" should
> > > catch most users.
> > >
> > > But it turns out that that nice cleanup step is fairly painful, because
> > > a _lot_ of code currently seems to depend on the implicit include of
> > > <linux/random.h>, which can currently come in a lot of ways, including
> > > such fairly core headfers as <linux/net.h>.
> > >
> > > So the "nice cleanup" part may or may never happen.
> > > --/quote--
> > >
> > > __percpu tag is currently defined in include/linux/compiler_types.h,
> > > so there is no direct need for the inclusion of <linux/percpu.h>.
> > > However, in [1] we would like to repurpose __percpu tag as a named
> > > address space qualifier, where __percpu macro uses defines from
> > > <linux/percpu.h>.
> > >
> > > This patch series is the "nice cleanup" part, and allows us to finally
> > > include <linux/percpu.h> in prandom.h.
> > >
> > > The whole series was tested by compiling the kernel for x86_64 allconfig
> > > and some popular architectures, namely arm64 defconfig, powerpc defconfig
> > > and loongarch defconfig.
> >
> > Obvious question(s) is(are):
> > 1) have you seen the Ingo's gigantic patch series towards resolving issues with
> > the headers?
> > 2) if not, please look at the preliminary work and take something from there, I
> > believe there are many useful changes already waiting for a couple of years to
> > be applied.
> >
> > Because I haven't found any references nor mentions of that in the cover letter
> > here and explanation why it was not taking into consideration.
> 
> I am aware of the series, but the patch takes only a small bite of it
> and specifically resolves the inclusion of <linux/prandom.h> from
> linux/random.h. The series fixes the missing inclusion of
> <linux/prandom.h> in files that use pseudo-random function and it was
> not meant to be a general header cleanup. The end goal is to allow us
> to include <linux/percpu.h> in linux/prandom.h - which uses __percpu
> tag without the correct include.

Thank you for elaboration, it's all clear now.

> Thus, the patch series is only tangentially connected to Ingo's patch series.

-- 
With Best Regards,
Andy Shevchenko



Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ