mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Dave Hansen <dave.hansen@intel.com>
To: Peter Zijlstra <peterz@infradead.org>, x86@kernel.org
Cc: linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
	oliver.sang@intel.com
Subject: Re: [PATCH 3/4] x86/mm: Inhibit _PAGE_NX changes from cpa_process_alias()
Date: Mon, 14 Nov 2022 08:08:16 -0800	[thread overview]
Message-ID: <333d37c3-7a9f-ac86-1a19-b5d61e1f59eb@intel.com> (raw)
In-Reply-To: <20221110125544.594991716@infradead.org>

On 11/10/22 04:52, Peter Zijlstra wrote:
> There is a cludge in change_page_attr_set_clr() that inhibits
> propagating NX changes to the aliases (directmap and highmap) -- this
> is a cludge twofold:
> 
>  - it also inhibits the primary checks in __change_page_attr();
>  - it hard depends on single bit changes.
> 
> The introduction of set_memory_rox() triggered this last issue for
> clearing both _PAGE_RW and _PAGE_NX.
> 
> Explicitly ignore _PAGE_NX in cpa_process_alias() instead.
> 
> Fixes: b38994948567 ("x86/mm: Implement native set_memory_rox()")
> Reported-by: kernel test robot <oliver.sang@intel.com>
> Debugged-by: Dave Hansen <dave.hansen@intel.com>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Looks sane.  It's also nice how the checkalias stuff continues to fall
out of there.

Acked-by: Dave Hansen <dave.hansen@intel.com>

  reply	other threads:[~2022-11-14 16:08 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-11-10 12:52 [PATCH 0/4] x86/mm: Fix set_memory_rox() Peter Zijlstra
2022-11-10 12:52 ` [PATCH 1/4] x86/mm: Add a few comments Peter Zijlstra
2022-11-10 16:22   ` Linus Torvalds
2022-11-10 18:02     ` Peter Zijlstra
2022-11-11 11:50       ` Peter Zijlstra
2022-11-10 12:52 ` [PATCH 2/4] x86/mm: Untangle __change_page_attr_set_clr(.checkalias) Peter Zijlstra
2022-11-10 12:52 ` [PATCH 3/4] x86/mm: Inhibit _PAGE_NX changes from cpa_process_alias() Peter Zijlstra
2022-11-14 16:08   ` Dave Hansen [this message]
2022-11-10 12:52 ` [PATCH 4/4] x86/mm: Rename __change_page_attr_set_clr(.checkalias) 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=333d37c3-7a9f-ac86-1a19-b5d61e1f59eb@intel.com \
    --to=dave.hansen@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=oliver.sang@intel.com \
    --cc=peterz@infradead.org \
    --cc=torvalds@linux-foundation.org \
    --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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®