From: Andrew Morton <akpm@linux-foundation.org>
To: Joerg Roedel <jroedel@suse.de>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>,
linux-mm@kvack.org, linux-kbuild@vger.kernel.org,
Dave Hansen <dave.hansen@linux.intel.com>,
Andy Lutomirski <luto@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
hpa@zytor.com
Subject: Re: [PATCH] mm/vmalloc: Fix regression caused by needless vmalloc_sync_all()
Date: Thu, 14 Nov 2019 16:01:08 -0800 [thread overview]
Message-ID: <20191114160108.57a72907f7b1aa9860471a06@linux-foundation.org> (raw)
In-Reply-To: <20191114171231.GA21753@suse.de>
On Thu, 14 Nov 2019 18:12:31 +0100 Joerg Roedel <jroedel@suse.de> wrote:
> On Wed, Nov 13, 2019 at 05:55:30PM +0800, Shile Zhang wrote:
> > +#if defined(CONFIG_X86_32) && defined(CONFIG_X86_PAE)
> > /*
> > * First make sure the mappings are removed from all page-tables
> > * before they are freed.
> > + *
> > + * This is only needed on x86-32 with !SHARED_KERNEL_PMD, which is
> > + * the case on a PAE kernel with PTI enabled.
> > */
> > - vmalloc_sync_all();
> > + if (!SHARED_KERNEL_PMD && boot_cpu_has(X86_FEATURE_PTI))
> > + vmalloc_sync_all();
> > +#endif
>
> I already submitted another fix for this quite some time ago:
>
> https://lore.kernel.org/lkml/20191009124418.8286-1-joro@8bytes.org/
>
Your patch is more verbose but looks quite a bit nicer than this patch
(Link:
http://lkml.kernel.org/r/20191113095530.228959-1-shile.zhang@linux.alibaba.com).
The separation of sync-for-a-mapping versus sync-for-an-unmapping adds
clarity.
It's fairly urgent - I consider this to be -stable material.
Thomas & co, was that a deliberate skip?
next prev parent reply other threads:[~2019-11-15 0:01 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-13 9:55 Shile Zhang
2019-11-13 15:17 ` Qian Cai
2019-11-13 21:12 ` Andrew Morton
2019-11-14 0:54 ` Shile Zhang
2019-11-14 13:56 ` Michal Hocko
2019-11-14 14:40 ` Shile Zhang
2019-11-14 17:14 ` Joerg Roedel
2019-11-14 17:12 ` Joerg Roedel
2019-11-15 0:01 ` Andrew Morton [this message]
2019-11-15 8:38 ` Borislav Petkov
2019-11-15 23:37 ` Andrew Morton
2019-11-16 17:38 ` Borislav Petkov
2019-11-15 1:06 ` Shile Zhang
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=20191114160108.57a72907f7b1aa9860471a06@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=hpa@zytor.com \
--cc=jroedel@suse.de \
--cc=linux-kbuild@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=luto@kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=shile.zhang@linux.alibaba.com \
--cc=tglx@linutronix.de \
/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