From: Paolo Bonzini <pbonzini@redhat.com>
To: Peter Xu <peterx@redhat.com>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Sean Christopherson <sean.j.christopherson@intel.com>,
linux-mips@vger.kernel.org,
Vitaly Kuznetsov <vkuznets@redhat.com>
Subject: Re: [PATCH RFC 0/4] KVM: MIPS: Provide arch-specific kvm_flush_remote_tlbs()
Date: Wed, 12 Feb 2020 13:25:30 +0100 [thread overview]
Message-ID: <44ba59d6-39a5-4221-1ae6-41e5a305d316@redhat.com> (raw)
In-Reply-To: <20200207223520.735523-1-peterx@redhat.com>
On 07/02/20 23:35, Peter Xu wrote:
> [This series is RFC because I don't have MIPS to compile and test]
>
> kvm_flush_remote_tlbs() can be arch-specific, by either:
>
> - Completely replace kvm_flush_remote_tlbs(), like ARM, who is the
> only user of CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL so far
>
> - Doing something extra before kvm_flush_remote_tlbs(), like MIPS VZ
> support, however still wants to have the common tlb flush to be part
> of the process. Could refer to kvm_vz_flush_shadow_all(). Then in
> MIPS it's awkward to flush remote TLBs: we'll need to call the mips
> hooks.
>
> It's awkward to have different ways to specialize this procedure,
> especially MIPS cannot use the genenal interface which is quite a
> pity. It's good to make it a common interface.
>
> This patch series removes the 2nd MIPS usage above, and let it also
> use the common kvm_flush_remote_tlbs() interface. It should be
> suggested that we always keep kvm_flush_remote_tlbs() be a common
> entrance for tlb flushing on all archs.
>
> This idea comes from the reading of Sean's patchset on dynamic memslot
> allocation, where a new dirty log specific hook is added for flushing
> TLBs only for the MIPS code [1]. With this patchset, logically the
> new hook in that patch can be dropped so we can directly use
> kvm_flush_remote_tlbs().
>
> TODO: We can even extend another common interface for ranged TLB, but
> let's see how we think about this series first.
>
> Any comment is welcomed, thanks.
>
> Peter Xu (4):
> KVM: Provide kvm_flush_remote_tlbs_common()
> KVM: MIPS: Drop flush_shadow_memslot() callback
> KVM: MIPS: Replace all the kvm_flush_remote_tlbs() references
> KVM: MIPS: Define arch-specific kvm_flush_remote_tlbs()
>
> arch/mips/include/asm/kvm_host.h | 7 -------
> arch/mips/kvm/Kconfig | 1 +
> arch/mips/kvm/mips.c | 22 ++++++++++------------
> arch/mips/kvm/trap_emul.c | 15 +--------------
> arch/mips/kvm/vz.c | 14 ++------------
> include/linux/kvm_host.h | 1 +
> virt/kvm/kvm_main.c | 10 ++++++++--
> 7 files changed, 23 insertions(+), 47 deletions(-)
>
Compile-tested and queued.
MIPS folks, I see that arch/mips/kvm/mmu.c uses pud_index, so it's not
clear to me if it's meant to only work if CONFIG_PGTABLE_LEVELS=4 or
it's just bit rot. Should I add a "depends on PGTABLE_LEVEL=4" to
arch/mips/Kconfig?
Paolo
next prev parent reply other threads:[~2020-02-12 12:25 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-07 22:35 [PATCH RFC 0/4] KVM: MIPS: Provide arch-specific kvm_flush_remote_tlbs() Peter Xu
2020-02-07 22:35 ` [PATCH RFC 1/4] KVM: Provide kvm_flush_remote_tlbs_common() Peter Xu
2020-02-12 13:33 ` Paolo Bonzini
2020-02-07 22:35 ` [PATCH RFC 2/4] KVM: MIPS: Drop flush_shadow_memslot() callback Peter Xu
2020-02-07 22:35 ` [PATCH RFC 3/4] KVM: MIPS: Replace all the kvm_flush_remote_tlbs() references Peter Xu
2020-02-07 22:35 ` [PATCH RFC 4/4] KVM: MIPS: Define arch-specific kvm_flush_remote_tlbs() Peter Xu
2020-03-18 3:03 ` maobibo
2020-03-18 15:28 ` Peter Xu
2020-03-19 2:21 ` maobibo
2020-02-07 23:00 ` [PATCH RFC 0/4] KVM: MIPS: Provide " Peter Xu
2020-02-12 12:25 ` Paolo Bonzini [this message]
2020-02-12 16:30 ` Paul Burton
2020-02-12 16:40 ` Paolo Bonzini
2020-02-12 19:02 ` Philippe Mathieu-Daudé
2020-03-11 18:32 ` Peter Xu
2020-03-17 13:33 ` Paolo Bonzini
2020-03-17 14:18 ` Peter Xu
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=44ba59d6-39a5-4221-1ae6-41e5a305d316@redhat.com \
--to=pbonzini@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mips@vger.kernel.org \
--cc=peterx@redhat.com \
--cc=sean.j.christopherson@intel.com \
--cc=vkuznets@redhat.com \
/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;
as well as URLs for NNTP newsgroup(s).