public inbox for linux-arm-kernel@lists.infradead.org 
 help / color / mirror / Atom feed
From: Catalin Marinas <catalin.marinas@arm•com>
To: Yassine Oudjana <y.oudjana@protonmail•com>
Cc: "will@kernel•org" <will@kernel•org>,
	"ardb@kernel•org" <ardb@kernel•org>,
	"arnd@arndb•de" <arnd@arndb•de>,
	"kernel-team@android•com" <kernel-team@android•com>,
	"linux-arm-kernel@lists•infradead.org"
	<linux-arm-kernel@lists•infradead.org>,
	 "mark.rutland@arm•com" <mark.rutland@arm•com>,
	"vincent.whitchurch@axis•com" <vincent.whitchurch@axis•com>,
	"linux-arm-msm@vger•kernel.org" <linux-arm-msm@vger•kernel.org>
Subject: Re: [PATCH] arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES)
Date: Tue, 6 Jul 2021 11:26:35 +0100	[thread overview]
Message-ID: <20210706102634.GB24903@arm.com> (raw)
In-Reply-To: <uHgsRacR8hJ7nW-I-pIcehzg-lNIn7NJvaL7bP9tfAftFsBjsgaY2qTjG9zyBgxHkjNL1WPNrD7YVv2JVD2_Wy-a5VTbcq-1xEi8ZnwrXBo=@protonmail.com>

On Tue, Jul 06, 2021 at 09:26:59AM +0000, Yassine Oudjana wrote:
> In-Reply-To: <20210527124356.22367-1-will@kernel•org>
> > Reduce ARCH_DMA_MINALIGN to 64 bytes and allow the warning/taint to
> > indicate if there are machines that unknowingly rely on this.
> 
> The warning is being triggered on Qualcomm MSM8996, as well as the out-of-spec taint:

Is this booting with ACPI or DT?

> ------------[ cut here ]------------
> rtc-pm8xxx 400f000.qcom,spmi:pmic@0:rtc@6000: ARCH_DMA_MINALIGN smaller than CTR_EL0.CWG (64 < 128)
> WARNING: CPU: 0 PID: 1 at arch/arm64/mm/dma-mapping.c:45 arch_setup_dma_ops+0xf8/0x10c
[...]
> This warning is triggered with nearly every driver probe, not only rtc-pm8xxx.

I have a suspicion none of the reported devices actually do any DMA, so
in practice it should be safe but we need to figure out why
arch_setup_dma_ops() gets called.

-- 
Catalin

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists•infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  parent reply	other threads:[~2021-07-06 10:28 UTC|newest]

Thread overview: 46+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CGME20210602132541eucas1p17127696041c26c00d1d2f50bef9cfaf0@eucas1p1.samsung.com>
2021-05-27 12:43 ` [PATCH] arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES) Will Deacon
2021-05-27 13:11   ` Catalin Marinas
2021-05-27 13:19   ` Mark Rutland
2021-05-28  9:35     ` Arnd Bergmann
2021-06-01 10:14       ` Catalin Marinas
2021-05-31  5:38   ` Ard Biesheuvel
2021-06-01 18:21   ` Will Deacon
2021-06-02 13:25   ` Marek Szyprowski
2021-06-02 13:51     ` Mark Rutland
2021-06-02 14:09       ` Marek Szyprowski
2021-06-02 14:14         ` Arnd Bergmann
2021-06-02 14:28           ` Marek Szyprowski
2021-06-02 14:52             ` Arnd Bergmann
2021-06-07 12:17               ` Arnd Bergmann
2021-06-04 10:01         ` Mark Rutland
2021-06-07  9:58           ` Marek Szyprowski
2021-06-07 12:01             ` Mark Rutland
2021-06-07 13:08               ` Mark Rutland
2021-06-07 13:39                 ` Will Deacon
2021-06-07 13:56                   ` Mark Rutland
2021-06-07 13:57                   ` Arnd Bergmann
2021-06-07 15:17                     ` Maxime Ripard
2021-06-07 15:50                       ` Arnd Bergmann
2021-06-08  8:57                         ` Mark Rutland
2021-06-07 15:32                     ` Mark Rutland
2021-06-02 14:11       ` Arnd Bergmann
2021-06-02 14:15         ` Marek Szyprowski
     [not found]   ` <uHgsRacR8hJ7nW-I-pIcehzg-lNIn7NJvaL7bP9tfAftFsBjsgaY2qTjG9zyBgxHkjNL1WPNrD7YVv2JVD2_Wy-a5VTbcq-1xEi8ZnwrXBo=@protonmail.com>
2021-07-06 10:26     ` Catalin Marinas [this message]
2021-07-06 13:29       ` Robin Murphy
2021-07-06 13:33         ` Will Deacon
2021-07-06 13:44           ` Marc Zyngier
2021-07-06 14:21             ` Robin Murphy
2021-07-06 14:30             ` Arnd Bergmann
2021-07-06 14:46               ` Marc Zyngier
2021-07-06 15:43                 ` Arnd Bergmann
2021-07-06 17:15                   ` Yassine Oudjana
2021-07-06 20:33                     ` Arnd Bergmann
2021-07-06 22:27                       ` Bjorn Andersson
2021-07-07  9:27                         ` Will Deacon
2021-07-07  8:24                       ` Yassine Oudjana
2021-07-07  9:29                         ` Arnd Bergmann
2021-07-07 14:41                           ` Jeffrey Hugo
2021-07-08 20:59                             ` Jeffrey Hugo
2021-07-09  8:48                               ` Will Deacon
2021-07-09 17:10                                 ` Catalin Marinas
2021-07-06 16:20               ` Will Deacon

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=20210706102634.GB24903@arm.com \
    --to=catalin.marinas@arm$(echo .)com \
    --cc=ardb@kernel$(echo .)org \
    --cc=arnd@arndb$(echo .)de \
    --cc=kernel-team@android$(echo .)com \
    --cc=linux-arm-kernel@lists$(echo .)infradead.org \
    --cc=linux-arm-msm@vger$(echo .)kernel.org \
    --cc=mark.rutland@arm$(echo .)com \
    --cc=vincent.whitchurch@axis$(echo .)com \
    --cc=will@kernel$(echo .)org \
    --cc=y.oudjana@protonmail$(echo .)com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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