From: Christoph Hellwig <hch@lst.de>
To: "Russell King (Oracle)" <linux@armlinux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>,
Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will@kernel.org>,
linux-arm-kernel@lists.infradead.org,
Mark Rutland <mark.rutland@arm.com>,
Robin Murphy <robin.murphy@arm.com>,
Ard Biesheuvel <ardb@kernel.org>
Subject: Re: [PATCH] arm64: dma: Drop cache invalidation from arch_dma_prep_coherent()
Date: Wed, 7 Sep 2022 16:14:41 +0200 [thread overview]
Message-ID: <20220907141441.GA21984@lst.de> (raw)
In-Reply-To: <YximWx/g2FjA/Ypl@shell.armlinux.org.uk>
On Wed, Sep 07, 2022 at 03:10:35PM +0100, Russell King (Oracle) wrote:
> If we allocate memory, clean (and maybe invalidate) the cache, and then
> zero the memory _after_ the clean, then couldn't we be creating dirty
> cache lines. There are caches out there that are write-allocate, which
> means that by writing zeros to memory, you drag cache lines back into
> the cache.
When writting through an uncached mapping?
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next prev parent reply other threads:[~2022-09-07 14:15 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-23 12:21 [PATCH] arm64: dma: Drop cache invalidation from arch_dma_prep_coherent() Will Deacon
2022-08-24 9:58 ` Ard Biesheuvel
2022-08-24 11:23 ` Will Deacon
2022-08-24 11:49 ` Ard Biesheuvel
2022-08-24 22:00 ` Catalin Marinas
2022-09-07 9:04 ` Christoph Hellwig
2022-09-07 14:10 ` Russell King (Oracle)
2022-09-07 14:14 ` Christoph Hellwig [this message]
2022-09-07 14:15 ` Russell King (Oracle)
2022-09-07 9:03 ` Christoph Hellwig
2022-09-07 9:27 ` Robin Murphy
2022-09-07 16:25 ` Will Deacon
2022-09-07 17:50 ` Robin Murphy
2022-09-08 10:32 ` Catalin Marinas
2022-09-08 11:32 ` Robin Murphy
2022-09-08 13:02 ` Catalin Marinas
2022-09-08 13:27 ` Catalin Marinas
2022-09-08 13:32 ` Will Deacon
2022-09-08 15:49 ` Catalin Marinas
2022-09-07 16:28 ` Will Deacon
2022-09-22 20:02 ` Catalin Marinas
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