From: Jason Gunthorpe <jgg@ziepe.ca>
To: Catalin Marinas <catalin.marinas@arm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org>,
linux-coco@lists.linux.dev, kvmarm@lists.linux.dev,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, iommu@lists.linux.dev,
Andrew Morton <akpm@linux-foundation.org>,
christian.koenig@amd.com, Joerg Roedel <joro@8bytes.org>,
Marc Zyngier <maz@kernel.org>,
Marek Szyprowski <m.szyprowski@samsung.com>,
Robin Murphy <robin.murphy@arm.com>,
Steven Price <steven.price@arm.com>,
Sumit Semwal <sumit.semwal@linaro.org>,
Suzuki K Poulose <suzuki.poulose@arm.com>,
Thomas Gleixner <tglx@kernel.org>, Will Deacon <will@kernel.org>,
dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org,
linux-media@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [RFC PATCH v7 02/13] mm: Add an allocator for CoCo shared memory
Date: Wed, 23 Sep 2026 10:06:11 -0300 [thread overview]
Message-ID: <20260923130611.GF1540250@ziepe.ca> (raw)
In-Reply-To: <arOspFxWZ1DjgcAr@arm.com>
On Wed, Sep 23, 2026 at 11:40:36AM +0100, Catalin Marinas wrote:
> The simplest is probably to always zero in the backend and ignore
> __GFP_ZERO to the allocator. But it's probably only marginally smaller
> than passing a CC_SHARED_ZERO flag down. Get codex to try this as well
> and compare the diffstat.
For patch ordering I would convert to use the allocator first
The semantics of the new API should be clear
If you pass GFP_ZERO then the resulting allocated memory is zero
Otherwise the allocator does Whatever The Arch Needs to not leak
private data out.
Once places are converted to the allocator lets go see what is left
and ask why it is left and what API it actually needs.
I think HCH was right that nobody should be calling this in driver
code, lets aim to unexport set_memory_decrypted as an ideal goal
Jason
next prev parent reply other threads:[~2026-09-23 13:06 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-21 14:48 [RFC PATCH v7 00/13] coco: guest: Add a shared-granule allocator for host-shared memory Aneesh Kumar K.V (Arm)
2026-09-21 14:48 ` [RFC PATCH v7 01/13] arm64: realm: Add RHI helper to query IPA state change alignment Aneesh Kumar K.V (Arm)
2026-09-21 14:48 ` [RFC PATCH v7 02/13] mm: Add an allocator for CoCo shared memory Aneesh Kumar K.V (Arm)
2026-09-22 16:25 ` Catalin Marinas
2026-09-22 16:51 ` Jason Gunthorpe
2026-09-23 0:33 ` Suzuki K Poulose
2026-09-23 5:53 ` Aneesh Kumar K.V
2026-09-23 8:31 ` Aneesh Kumar K.V
2026-09-23 10:10 ` Catalin Marinas
2026-09-23 9:42 ` Catalin Marinas
2026-09-23 9:59 ` Aneesh Kumar K.V
2026-09-23 10:28 ` Aneesh Kumar K.V
2026-09-23 10:40 ` Catalin Marinas
2026-09-23 13:06 ` Jason Gunthorpe [this message]
2026-09-23 14:58 ` Aneesh Kumar K.V
2026-09-23 15:11 ` Suzuki K Poulose
2026-09-23 15:21 ` Jason Gunthorpe
2026-09-23 16:28 ` Kameron Carr
2026-09-23 17:23 ` Jason Gunthorpe
2026-09-23 18:36 ` Michael Kelley
2026-09-23 13:00 ` Jason Gunthorpe
2026-09-23 15:20 ` Mostafa Saleh
2026-09-21 14:48 ` [RFC PATCH v7 03/13] arm64: realm: Expose the CCA shared granule size through mem_encrypt ops Aneesh Kumar K.V (Arm)
2026-09-21 14:48 ` [RFC PATCH v7 04/13] irqchip/gic-v3-its: Resolve the default NUMA node explicitly Aneesh Kumar K.V (Arm)
2026-09-21 14:48 ` [RFC PATCH v7 05/13] irqchip/gic-v3-its: Allocate shared tables using CoCo shared memory allocator Aneesh Kumar K.V (Arm)
2026-09-21 14:48 ` [RFC PATCH v7 06/13] dma-contiguous: Accept an explicit minimum alignment Aneesh Kumar K.V (Arm)
2026-09-23 10:35 ` Catalin Marinas
2026-09-23 11:49 ` Aneesh Kumar K.V
2026-09-23 13:49 ` Catalin Marinas
2026-09-21 14:48 ` [RFC PATCH v7 07/13] dma-pool: Allocate CoCo atomic pools using CoCo shared memory allocator Aneesh Kumar K.V (Arm)
2026-09-21 14:48 ` [RFC PATCH v7 08/13] dma-direct: Align CoCo shared DMA allocations to the shared granule size Aneesh Kumar K.V (Arm)
2026-09-21 14:48 ` [RFC PATCH v7 09/13] swiotlb: Align shared IO TLB pools " Aneesh Kumar K.V (Arm)
2026-09-21 14:48 ` [RFC PATCH v7 10/13] swiotlb: Reject misaligned restricted DMA pools for CoCo guests Aneesh Kumar K.V (Arm)
2026-09-21 14:48 ` [RFC PATCH v7 11/13] dma-buf: system_heap: Limit scatterlist entries to the buffer size Aneesh Kumar K.V (Arm)
2026-09-21 14:48 ` [RFC PATCH v7 12/13] dma-buf: system_heap: Allocate shared buffers using CoCo shared memory allocator Aneesh Kumar K.V (Arm)
2026-09-22 16:39 ` Catalin Marinas
2026-09-23 8:32 ` Aneesh Kumar K.V
2026-09-23 8:46 ` Christian König
2026-09-21 14:48 ` [RFC PATCH v7 13/13] swiotlb: Make rounded shared pool capacity allocatable Aneesh Kumar K.V (Arm)
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=20260923130611.GF1540250@ziepe.ca \
--to=jgg@ziepe.ca \
--cc=akpm@linux-foundation.org \
--cc=aneesh.kumar@kernel.org \
--cc=catalin.marinas@arm.com \
--cc=christian.koenig@amd.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=iommu@lists.linux.dev \
--cc=joro@8bytes.org \
--cc=kvmarm@lists.linux.dev \
--cc=linaro-mm-sig@lists.linaro.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-coco@lists.linux.dev \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=m.szyprowski@samsung.com \
--cc=maz@kernel.org \
--cc=robin.murphy@arm.com \
--cc=steven.price@arm.com \
--cc=sumit.semwal@linaro.org \
--cc=suzuki.poulose@arm.com \
--cc=tglx@kernel.org \
--cc=will@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®