All of lore.kernel.org
 help / color / mirror / Atom feed
From: Andy Lutomirski <luto@kernel.org>
To: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
	"Luck, Tony" <tony.luck@intel.com>,
	Ingo Molnar <mingo@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	H Peter Anvin <hpa@zytor.com>, "Raj, Ashok" <ashok.raj@intel.com>,
	"Shankar, Ravi V" <ravi.v.shankar@intel.com>,
	linux-kernel <linux-kernel@vger.kernel.org>, x86 <x86@kernel.org>
Subject: Re: [PATCH v10 6/6] x86/split_lock: Enable split lock detection by kernel parameter
Date: Fri, 22 Nov 2019 13:25:45 -0800	[thread overview]
Message-ID: <CALCETrUBomb2_2xyX-tZUD84smtDWH6e16zSN1qupkv-DWu5kw@mail.gmail.com> (raw)
In-Reply-To: <20191122204204.GA192370@romley-ivt3.sc.intel.com>

On Fri, Nov 22, 2019 at 12:29 PM Fenghua Yu <fenghua.yu@intel.com> wrote:
>
> On Fri, Nov 22, 2019 at 09:23:45PM +0100, Peter Zijlstra wrote:
> > On Fri, Nov 22, 2019 at 06:02:04PM +0000, Luck, Tony wrote:
> > > > it requires we get the kernel and firmware clean, but only warns about
> > > > dodgy userspace, which I really don't think there is much of.
> > > >
> > > > getting the kernel clean should be pretty simple.
> > >
> > > Fenghua has a half dozen additional patches (I think they were
> > > all posted in previous iterations of the patch) that were found by
> > > code inspection, rather than by actually hitting them.
> >
> > I thought we merged at least some of that, but maybe my recollection is
> > faulty.
>
> At least 2 key fixes are in TIP tree:
> https://lore.kernel.org/lkml/157384597983.12247.8995835529288193538.tip-bot2@tip-bot2/
> https://lore.kernel.org/lkml/157384597947.12247.7200239597382357556.tip-bot2@tip-bot2/

I do not like these patches at all.  I would *much* rather see the
bitops fixed and those patches reverted.

Is there any Linux architecture that doesn't have 32-bit atomic
operations?  If all architectures can support them, then we should add
set_bit_u32(), etc and/or make x86's set_bit() work for a
4-byte-aligned pointer.

--Andy

  reply	other threads:[~2019-11-22 21:26 UTC|newest]

Thread overview: 145+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-21  0:53 [PATCH v10 0/6] Enable split lock detection for real time and debug Fenghua Yu
2019-11-21  0:53 ` [PATCH v10 1/6] x86/msr-index: Add two new MSRs Fenghua Yu
2019-11-21  0:53 ` [PATCH v10 2/6] x86/cpufeatures: Enumerate the IA32_CORE_CAPABILITIES MSR Fenghua Yu
2019-11-21  0:53 ` [PATCH v10 3/6] x86/split_lock: Enumerate split lock detection by " Fenghua Yu
2019-11-21  0:53 ` [PATCH v10 4/6] x86/split_lock: Enumerate split lock detection if the IA32_CORE_CAPABILITIES MSR is not supported Fenghua Yu
2019-11-21 22:07   ` Andy Lutomirski
2019-11-22  0:37     ` Fenghua Yu
2019-11-22  2:13       ` Andy Lutomirski
2019-11-22  9:46         ` Peter Zijlstra
2019-11-21  0:53 ` [PATCH v10 5/6] x86/split_lock: Handle #AC exception for split lock Fenghua Yu
2019-11-21 22:10   ` Andy Lutomirski
2019-11-21 23:14     ` Fenghua Yu
2019-11-21 23:12       ` Andy Lutomirski
2019-11-21  0:53 ` [PATCH v10 6/6] x86/split_lock: Enable split lock detection by kernel parameter Fenghua Yu
2019-11-21  6:04   ` Ingo Molnar
2019-11-21 13:01     ` Peter Zijlstra
2019-11-21 13:15       ` Peter Zijlstra
2019-11-21 21:51         ` Luck, Tony
2019-11-21 22:24           ` Andy Lutomirski
2019-11-21 22:29             ` Luck, Tony
2019-11-21 23:18               ` Andy Lutomirski
2019-11-21 23:53                 ` Fenghua Yu
2019-11-22  1:52                   ` Sean Christopherson
2019-11-22  2:21                     ` Andy Lutomirski
2019-11-22  2:39                       ` Xiaoyao Li
2019-11-22  2:57                         ` Andy Lutomirski
2019-11-21 23:55                 ` Luck, Tony
2019-11-22  0:55             ` Luck, Tony
2019-11-22 10:08           ` Peter Zijlstra
2019-11-21 16:14       ` Fenghua Yu
2019-11-21 17:14         ` Ingo Molnar
2019-11-21 17:35         ` Peter Zijlstra
2019-11-21 17:12       ` Ingo Molnar
2019-11-21 17:34         ` Luck, Tony
2019-11-22 10:51           ` Peter Zijlstra
2019-11-22 15:27             ` Peter Zijlstra
2019-11-22 17:22               ` Luck, Tony
2019-11-22 20:23                 ` Peter Zijlstra
2019-11-22 18:02               ` Luck, Tony
2019-11-22 20:23                 ` Peter Zijlstra
2019-11-22 20:42                   ` Fenghua Yu
2019-11-22 21:25                     ` Andy Lutomirski [this message]
2019-12-12  8:57                       ` Peter Zijlstra
2019-12-12 18:52                         ` Luck, Tony
2019-12-12 19:46                           ` Luck, Tony
2019-12-12 20:01                             ` Andy Lutomirski
2019-12-16 16:21                               ` David Laight
2019-11-22 18:44               ` Sean Christopherson
2019-11-22 20:30                 ` Peter Zijlstra
2019-11-23  0:30               ` Luck, Tony
2019-11-25 16:13                 ` Sean Christopherson
2019-12-02 18:20                   ` Luck, Tony
2019-12-12  8:59                   ` Peter Zijlstra
2020-01-10 19:24                     ` [PATCH v11] x86/split_lock: Enable split lock detection by kernel Luck, Tony
2020-01-14  5:55                       ` Sean Christopherson
2020-01-15 22:27                         ` Luck, Tony
2020-01-15 22:57                           ` Sean Christopherson
2020-01-15 23:48                             ` Luck, Tony
2020-01-22 18:55                             ` [PATCH v12] " Luck, Tony
2020-01-22 19:04                               ` Borislav Petkov
2020-01-22 20:03                                 ` Luck, Tony
2020-01-22 20:55                                   ` Borislav Petkov
2020-01-22 22:42                               ` Arvind Sankar
2020-01-22 22:52                                 ` Arvind Sankar
2020-01-22 23:24                                 ` Luck, Tony
2020-01-23  0:45                                   ` Arvind Sankar
2020-01-23  1:23                                     ` Luck, Tony
2020-01-23  4:21                                       ` Arvind Sankar
2020-01-23 17:15                                         ` Luck, Tony
2020-01-23  3:53                                     ` [PATCH v13] " Luck, Tony
2020-01-23  4:45                                       ` Arvind Sankar
2020-01-23 23:16                                         ` [PATCH v14] " Luck, Tony
2020-01-24 21:36                                           ` Thomas Gleixner
2020-01-25  2:47                                             ` [PATCH v15] " Luck, Tony
2020-01-25 10:44                                               ` Borislav Petkov
2020-01-25 19:55                                                 ` Luck, Tony
2020-01-25 20:12                                                   ` Peter Zijlstra
2020-01-25 20:33                                                     ` Borislav Petkov
2020-01-25 21:42                                                       ` Luck, Tony
2020-01-25 22:17                                                         ` Borislav Petkov
2020-01-25 20:29                                                   ` Borislav Petkov
2020-01-25 13:41                                               ` Thomas Gleixner
2020-01-25 22:07                                                 ` [PATCH v16] " Luck, Tony
2020-01-25 22:43                                                   ` Mark D Rustad
2020-01-25 23:10                                                     ` Luck, Tony
2020-01-26 17:27                                                       ` Mark D Rustad
2020-01-26 20:05                                                         ` [PATCH v17] " Luck, Tony
2020-01-29 12:31                                                           ` Thomas Gleixner
2020-01-29 15:24                                                           ` [tip: x86/cpu] " tip-bot2 for Peter Zijlstra (Intel)
2020-02-03 20:41                                                           ` [PATCH v17] " Sean Christopherson
2020-02-06  0:49                                                             ` [PATCH] x86/split_lock: Avoid runtime reads of the TEST_CTRL MSR Luck, Tony
2020-02-06  1:18                                                               ` Andy Lutomirski
2020-02-06 16:46                                                                 ` Luck, Tony
2020-02-06 19:37                                                                   ` Andy Lutomirski
2020-03-03 19:22                                                                     ` Sean Christopherson
2020-02-04  0:04                                                           ` [PATCH v17] x86/split_lock: Enable split lock detection by kernel Sean Christopherson
2020-02-04 12:52                                                             ` Thomas Gleixner
2020-01-26  0:34                                                   ` [PATCH v16] " Andy Lutomirski
2020-01-26 20:01                                                     ` Luck, Tony
2020-01-25 21:25                                               ` [PATCH v15] " Arvind Sankar
2020-01-25 21:50                                                 ` Luck, Tony
2020-01-25 23:51                                                   ` Arvind Sankar
2020-01-26  2:52                                                     ` Luck, Tony
2020-01-27  2:05                                                       ` Tony Luck
2020-01-27  8:04                                                   ` Peter Zijlstra
2020-01-27  8:36                                                     ` Peter Zijlstra
2020-01-27 17:35                                                     ` Luck, Tony
2020-01-27  8:02                                                 ` Peter Zijlstra
2019-12-13  0:09               ` [PATCH v11] x86/split_lock: Enable split lock detection by kernel parameter Tony Luck
2019-12-13  0:16                 ` Luck, Tony
2019-11-21 17:43         ` [PATCH v10 6/6] " David Laight
2019-11-21 17:51           ` Andy Lutomirski
2019-11-21 18:53             ` Fenghua Yu
2019-11-21 19:01               ` Andy Lutomirski
2019-11-21 20:25                 ` Fenghua Yu
2019-11-21 20:19                   ` Peter Zijlstra
2019-11-21 19:46               ` Peter Zijlstra
2019-11-21 20:25               ` Peter Zijlstra
2019-11-21 21:22                 ` Andy Lutomirski
2019-11-22  9:25                   ` Peter Zijlstra
2019-11-22 17:48                     ` Luck, Tony
2019-11-22 20:31                       ` Peter Zijlstra
2019-11-22 21:23                         ` Andy Lutomirski
2019-12-11 17:52                           ` Peter Zijlstra
2019-12-11 18:12                             ` Andy Lutomirski
2019-12-11 22:34                               ` Peter Zijlstra
2019-12-12 19:40                                 ` Andy Lutomirski
2019-12-16  9:59                                   ` David Laight
2019-12-16 17:22                                     ` Andy Lutomirski
2019-12-16 17:45                                       ` David Laight
2019-12-16 18:06                                         ` Andy Lutomirski
2019-12-17 10:03                                           ` David Laight
2019-12-11 18:44                             ` Luck, Tony
2019-12-11 22:39                               ` Peter Zijlstra
2019-12-12 10:36                                 ` David Laight
2019-12-12 13:04                                   ` Peter Zijlstra
2019-12-12 16:02                                     ` Andy Lutomirski
2019-12-12 16:23                                       ` David Laight
2019-12-12 16:29                                     ` David Laight
2019-11-21 19:56             ` Peter Zijlstra
2019-11-21 21:01               ` Andy Lutomirski
2019-11-22  9:36                 ` Peter Zijlstra
2019-11-22  9:46             ` David Laight
2019-11-22 20:32               ` Peter Zijlstra
2019-11-21  8:00   ` Peter Zijlstra

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=CALCETrUBomb2_2xyX-tZUD84smtDWH6e16zSN1qupkv-DWu5kw@mail.gmail.com \
    --to=luto@kernel.org \
    --cc=ashok.raj@intel.com \
    --cc=bp@alien8.de \
    --cc=fenghua.yu@intel.com \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.org \
    --cc=ravi.v.shankar@intel.com \
    --cc=tglx@linutronix.de \
    --cc=tony.luck@intel.com \
    --cc=x86@kernel.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.