From: Catalin Marinas <catalin.marinas@arm.com>
To: ankita@nvidia.com
Cc: jgg@nvidia.com, maz@kernel.org, oliver.upton@linux.dev,
joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com,
will@kernel.org, ryan.roberts@arm.com, shahuang@redhat.com,
lpieralisi@kernel.org, david@redhat.com, ddutile@redhat.com,
seanjc@google.com, aniketa@nvidia.com, cjia@nvidia.com,
kwankhede@nvidia.com, kjaju@nvidia.com, targupta@nvidia.com,
vsethi@nvidia.com, acurrid@nvidia.com, apopple@nvidia.com,
jhubbard@nvidia.com, danw@nvidia.com, zhiw@nvidia.com,
mochs@nvidia.com, udhoke@nvidia.com, dnigam@nvidia.com,
alex.williamson@redhat.com, sebastianene@google.com,
coltonlewis@google.com, kevin.tian@intel.com, yi.l.liu@intel.com,
ardb@kernel.org, akpm@linux-foundation.org, gshan@redhat.com,
linux-mm@kvack.org, tabba@google.com, qperret@google.com,
kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org, maobibo@loongson.cn
Subject: Re: [PATCH v10 6/6] KVM: arm64: Expose new KVM cap for cacheable PFNMAP
Date: Sun, 6 Jul 2025 20:02:35 -0500 [thread overview]
Message-ID: <aGscq_R69UpMXpGX@arm.com> (raw)
In-Reply-To: <20250705071717.5062-7-ankita@nvidia.com>
On Sat, Jul 05, 2025 at 07:17:17AM +0000, ankita@nvidia.com wrote:
> From: Ankit Agrawal <ankita@nvidia.com>
>
> Introduce a new KVM capability to expose to the userspace whether
> cacheable mapping of PFNMAP is supported.
>
> The ability to safely do the cacheable mapping of PFNMAP is contingent
> on S2FWB and ARM64_HAS_CACHE_DIC. S2FWB allows KVM to avoid flushing
> the D cache, ARM64_HAS_CACHE_DIC allows KVM to avoid flushing the icache
> and turns icache_inval_pou() into a NOP. The cap would be false if
> those requirements are missing and is checked by making use of
> kvm_arch_supports_cacheable_pfnmap.
>
> This capability would allow userspace to discover the support.
> It could for instance be used by userspace to prevent live-migration
> across FWB and non-FWB hosts.
>
> CC: Catalin Marinas <catalin.marinas@arm.com>
> CC: Jason Gunthorpe <jgg@nvidia.com>
> CC: Oliver Upton <oliver.upton@linux.dev>
> CC: David Hildenbrand <david@redhat.com>
> Suggested-by: Marc Zyngier <maz@kernel.org>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Tested-by: Donald Dutile <ddutile@redhat.com>
> Signed-off-by: Ankit Agrawal <ankita@nvidia.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
next prev parent reply other threads:[~2025-07-07 1:03 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-05 7:17 [PATCH v10 0/6] KVM: arm64: Map GPU device memory as cacheable ankita
2025-07-05 7:17 ` [PATCH v10 1/6] KVM: arm64: Rename the device variable to s2_force_noncacheable ankita
2025-07-07 0:51 ` Catalin Marinas
2025-07-05 7:17 ` [PATCH v10 2/6] KVM: arm64: Update the check to detect device memory ankita
2025-07-07 0:52 ` Catalin Marinas
2025-07-05 7:17 ` [PATCH v10 3/6] KVM: arm64: Block cacheable PFNMAP mapping ankita
2025-07-07 0:54 ` Catalin Marinas
2025-07-05 7:17 ` [PATCH v10 4/6] KVM: arm64: New function to determine hardware cache management support ankita
2025-07-05 7:17 ` [PATCH v10 5/6] KVM: arm64: Allow cacheable stage 2 mapping using VMA flags ankita
2025-07-07 1:00 ` Catalin Marinas
2025-07-07 7:32 ` David Hildenbrand
2025-07-07 12:27 ` Jason Gunthorpe
2025-07-05 7:17 ` [PATCH v10 6/6] KVM: arm64: Expose new KVM cap for cacheable PFNMAP ankita
2025-07-07 1:02 ` Catalin Marinas [this message]
2025-07-07 16:39 ` [PATCH v10 0/6] KVM: arm64: Map GPU device memory as cacheable Ankit Agrawal
2025-07-07 23:57 ` Oliver Upton
2025-07-09 14:34 ` Ankit Agrawal
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=aGscq_R69UpMXpGX@arm.com \
--to=catalin.marinas@arm.com \
--cc=acurrid@nvidia.com \
--cc=akpm@linux-foundation.org \
--cc=alex.williamson@redhat.com \
--cc=aniketa@nvidia.com \
--cc=ankita@nvidia.com \
--cc=apopple@nvidia.com \
--cc=ardb@kernel.org \
--cc=cjia@nvidia.com \
--cc=coltonlewis@google.com \
--cc=danw@nvidia.com \
--cc=david@redhat.com \
--cc=ddutile@redhat.com \
--cc=dnigam@nvidia.com \
--cc=gshan@redhat.com \
--cc=jgg@nvidia.com \
--cc=jhubbard@nvidia.com \
--cc=joey.gouly@arm.com \
--cc=kevin.tian@intel.com \
--cc=kjaju@nvidia.com \
--cc=kvmarm@lists.linux.dev \
--cc=kwankhede@nvidia.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=lpieralisi@kernel.org \
--cc=maobibo@loongson.cn \
--cc=maz@kernel.org \
--cc=mochs@nvidia.com \
--cc=oliver.upton@linux.dev \
--cc=qperret@google.com \
--cc=ryan.roberts@arm.com \
--cc=seanjc@google.com \
--cc=sebastianene@google.com \
--cc=shahuang@redhat.com \
--cc=suzuki.poulose@arm.com \
--cc=tabba@google.com \
--cc=targupta@nvidia.com \
--cc=udhoke@nvidia.com \
--cc=vsethi@nvidia.com \
--cc=will@kernel.org \
--cc=yi.l.liu@intel.com \
--cc=yuzenghui@huawei.com \
--cc=zhiw@nvidia.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.