From: "Arnd Bergmann" <arnd@arndb.de>
To: "Qingfang Deng" <qingfang.deng@linux.dev>,
"Catalin Marinas" <catalin.marinas@arm.com>,
"Will Deacon" <will@kernel.org>,
"Mark Rutland" <mark.rutland@arm.com>,
"Anshuman Khandual" <anshuman.khandual@arm.com>,
"Vikram Sethi" <vsethi@nvidia.com>,
"Mike Rapoport" <rppt@kernel.org>,
"Shanker Donthineni" <sdonthineni@nvidia.com>,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org
Cc: Linux-Arch <linux-arch@vger.kernel.org>
Subject: Re: [PATCH v2 3/3] arm64: use generic MMIO accessors
Date: Sun, 20 Sep 2026 10:08:18 +0200 [thread overview]
Message-ID: <5847c824-8d69-4d02-af2f-896bf47f0732@app.fastmail.com> (raw)
In-Reply-To: <20260920014357.7069-3-qingfang.deng@linux.dev>
On Sun, Sep 20, 2026, at 03:43, Qingfang Deng wrote:
> Use the generic raw write accessors in place of the inline assembly
> stores. Include asm-generic/mmio.h after the arm64 ordering hooks so
> these accessors are also available to the write-combining helpers
> before asm-generic/io.h is included.
>
> Retain the raw read overrides when either the Cortex-A57 erratum 832075
> or NVIDIA Olympus erratum 1027 workaround is configured. This preserves
> the alternative-patched load-acquire instructions and pre-load barriers.
> Use generic raw reads when neither workaround is enabled.
>
> Assisted-by: Codex:gpt-6-astra
> Signed-off-by: Qingfang Deng <qingfang.deng@linux.dev>
Sorry, this is no good, we need the compiler to issue the exact
instructions from the inline asm here, both in order to guarantee
these can be virtualized, and to prevent it from splitting up
larger register accesses into byte load/store on unaligned pointers.
Arnd
next prev parent reply other threads:[~2026-09-20 8:08 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-20 1:43 [PATCH v2 1/3] asm-generic: split MMIO accessors out of io.h Qingfang Deng
2026-09-20 1:43 ` [PATCH v2 2/3] riscv: use generic MMIO accessors Qingfang Deng
2026-09-20 8:11 ` Arnd Bergmann
2026-09-20 1:43 ` [PATCH v2 3/3] arm64: " Qingfang Deng
2026-09-20 8:08 ` Arnd Bergmann [this message]
2026-09-20 9:24 ` Qingfang Deng
2026-09-20 9:30 ` Arnd Bergmann
2026-09-20 9:35 ` Arnd Bergmann
2026-09-20 8:13 ` [PATCH v2 1/3] asm-generic: split MMIO accessors out of io.h Arnd Bergmann
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=5847c824-8d69-4d02-af2f-896bf47f0732@app.fastmail.com \
--to=arnd@arndb.de \
--cc=anshuman.khandual@arm.com \
--cc=catalin.marinas@arm.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=qingfang.deng@linux.dev \
--cc=rppt@kernel.org \
--cc=sdonthineni@nvidia.com \
--cc=vsethi@nvidia.com \
--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®