Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1357988

Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table

From Borislav Petkov <bp@alien8.de>
Newsgroups linux.kernel
Subject Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table
Date 2016-03-15 12:10 +0100
Message-ID <rcV1n-1e9-9@gated-at.bofh.it> (permalink)
References (3 earlier) <rbxkt-8dl-7@gated-at.bofh.it> <rbxDP-8op-1@gated-at.bofh.it> <rbA8G-1R9-35@gated-at.bofh.it> <rbQn8-5qL-13@gated-at.bofh.it> <rcHB8-pu-13@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Mon, Mar 14, 2016 at 03:37:23PM -0600, Toshi Kani wrote:
> Your patch is a simplified version of mine.  So, yes, it fixes the Paul's
> issue, but it does not address other issues that my patchset also
> addressed.  In specific, I think your patch has the following issues.

You couldnt've structured your reply better: remember how I split a
convoluted patch of yours already? A patch which was trying to do a
bunch of things in one go.

The situation here is the same. You need to do *one* *logical*
*non-trivial* thing in a patch. If there's something else that needs to
be done, add it in a *separate* patch which explains why that new change
is needed.

> - pat_disable() is now callable from other modules. So, it needs to check
> with boot_cpu_done. We cannot disable PAT once it is initialized.

That should be a separate patch which explains *why* the change is being
done.

> - mtrr_bp_init() needs to check with mtrr_enabled() when it
> calls mtrr_pat_setup_bp(). Otherwise, PAT is left initialized on BSP only
> when MTRR is disabled by its MSR. In your patch, mtrr_bp_init() calls
> pat_setup() again, but it does not help since boot_cpu_done is set.

The code which you carved out from get_mtrr_state() didn't check
mtrr_enabled() before. That needs to be another patch *again* with
explanations.

> - When PAT is disabled in CPU feature, pat_bsp_init() calls pat_disable()
> and returns. However, it does not initialize a PAT table by calling
> pat_init_cache_modes().

Yet another patch.

> - When CONFIG_MTRR is unset, it does not call pat_setup().

Aaaand... can you guess what I'm going to say here?

I hope it is coming across as I intend it: please use my hunk to do a
single fix and then prepare all those changes above in separate patches
with explanations:

"Problem is A. We need to do B. I'm doing it/I'm doing C because."

Ok?

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH 0/2] Refactor MTRR and PAT initializations Toshi Kani <toshi.kani@hpe.com> - 2016-03-11 05:00 +0100
  [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table Toshi Kani <toshi.kani@hpe.com> - 2016-03-11 05:00 +0100
    Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table Borislav Petkov <bp@alien8.de> - 2016-03-11 10:20 +0100
      Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT  table Toshi Kani <toshi.kani@hpe.com> - 2016-03-11 16:40 +0100
        Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table Borislav Petkov <bp@alien8.de> - 2016-03-11 17:00 +0100
          Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT  table Toshi Kani <toshi.kani@hpe.com> - 2016-03-11 19:40 +0100
            Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table Borislav Petkov <bp@alien8.de> - 2016-03-12 13:00 +0100
              Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT  table Toshi Kani <toshi.kani@hpe.com> - 2016-03-14 21:50 +0100
                Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table Borislav Petkov <bp@alien8.de> - 2016-03-15 12:10 +0100
                Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT  table Toshi Kani <toshi.kani@hpe.com> - 2016-03-15 22:10 +0100
              Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table "Luis R. Rodriguez" <mcgrof@kernel.org> - 2016-03-15 01:30 +0100
                Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT  table Toshi Kani <toshi.kani@hpe.com> - 2016-03-15 03:20 +0100
                Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table Borislav Petkov <bp@alien8.de> - 2016-03-15 12:10 +0100
                Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT  table Toshi Kani <toshi.kani@hpe.com> - 2016-03-15 16:00 +0100
                Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table Borislav Petkov <bp@alien8.de> - 2016-03-15 16:50 +0100
                Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT  table Toshi Kani <toshi.kani@hpe.com> - 2016-03-15 17:20 +0100
                Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table Borislav Petkov <bp@alien8.de> - 2016-03-15 17:40 +0100
                Re: [PATCH 1/2] x86/mm/pat: Change pat_disable() to emulate PAT table "Luis R. Rodriguez" <mcgrof@kernel.org> - 2016-03-15 22:40 +0100
  [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Toshi Kani <toshi.kani@hpe.com> - 2016-03-11 05:00 +0100
    Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Ingo Molnar <mingo@kernel.org> - 2016-03-11 10:10 +0100
      Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Ingo Molnar <mingo@kernel.org> - 2016-03-11 10:20 +0100
        Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Toshi Kani <toshi.kani@hpe.com> - 2016-03-11 18:50 +0100
          Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Ingo Molnar <mingo@kernel.org> - 2016-03-12 17:20 +0100
            Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Toshi Kani <toshi.kani@hpe.com> - 2016-03-14 20:00 +0100
          Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code "Luis R. Rodriguez" <mcgrof@suse.com> - 2016-03-15 00:00 +0100
            Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Toshi Kani <toshi.kani@hpe.com> - 2016-03-15 00:50 +0100
              Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Borislav Petkov <bp@suse.de> - 2016-03-15 17:00 +0100
    Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Borislav Petkov <bp@alien8.de> - 2016-03-11 10:30 +0100
      Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Toshi Kani <toshi.kani@hpe.com> - 2016-03-11 19:10 +0100
        Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code "Luis R. Rodriguez" <mcgrof@kernel.org> - 2016-03-11 23:20 +0100
          Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Toshi Kani <toshi.kani@hpe.com> - 2016-03-12 00:10 +0100
            Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code "Luis R. Rodriguez" <mcgrof@kernel.org> - 2016-03-12 00:40 +0100
              Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Toshi Kani <toshi.kani@hpe.com> - 2016-03-12 01:30 +0100
                Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code "Luis R. Rodriguez" <mcgrof@kernel.org> - 2016-03-15 01:20 +0100
                Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code Toshi Kani <toshi.kani@hpe.com> - 2016-03-16 00:00 +0100
                Re: [PATCH 2/2] x86/mtrr: Refactor PAT initialization code "Luis R. Rodriguez" <mcgrof@kernel.org> - 2016-03-16 00:30 +0100

csiph-web