From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
To: Juergen Gross <jgross@suse.com>,
linux-kernel@vger.kernel.org, x86@kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
"H. Peter Anvin" <hpa@zytor.com>,
xen-devel@lists.xenproject.org
Subject: Re: [PATCH 3/3] x86/xen: allow nesting of same lazy mode
Date: Fri, 15 Sep 2023 17:50:11 -0400 [thread overview]
Message-ID: <c243936e-bda3-eb3f-1725-323772ad3a7d@oracle.com> (raw)
In-Reply-To: <20230913113828.18421-4-jgross@suse.com>
On 9/13/23 7:38 AM, Juergen Gross wrote:
> When running as a paravirtualized guest under Xen, Linux is using
> "lazy mode" for issuing hypercalls which don't need to take immediate
> effect in order to improve performance (examples are e.g. multiple
> PTE changes).
>
> There are two different lazy modes defined: MMU and CPU lazy mode.
> Today it is not possible to nest multiple lazy mode sections, even if
> they are of the same kind. A recent change in memory management added
> nesting of MMU lazy mode sections, resulting in a regression when
> running as Xen PV guest.
>
> Technically there is no reason why nesting of multiple sections of the
> same kind of lazy mode shouldn't be allowed. So add support for that
> for fixing the regression.
>
> Fixes: bcc6cc832573 ("mm: add default definition of set_ptes()")
> Signed-off-by: Juergen Gross <jgross@suse.com>
For patches 2 and 3
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
prev parent reply other threads:[~2023-09-15 21:52 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-13 11:38 [PATCH 0/3] xen: cleanup and fix lazy mode handling Juergen Gross
2023-09-13 11:38 ` [PATCH 1/3] arm/xen: remove lazy mode related definitions Juergen Gross
2023-09-13 23:07 ` Stefano Stabellini
2023-09-13 11:38 ` [PATCH 2/3] x86/xen: move paravirt lazy code Juergen Gross
2023-09-13 13:26 ` Steven Rostedt
2023-09-13 13:36 ` Juergen Gross
2023-09-13 11:38 ` [PATCH 3/3] x86/xen: allow nesting of same lazy mode Juergen Gross
2023-09-15 21:50 ` Boris Ostrovsky [this message]
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=c243936e-bda3-eb3f-1725-323772ad3a7d@oracle.com \
--to=boris.ostrovsky@oracle.com \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=hpa@zytor.com \
--cc=jgross@suse.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
--cc=xen-devel@lists.xenproject.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®