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From: Christoph Hellwig <hch@lst.de>
To: Chintan Pandya <cpandya@codeaurora.org>
Cc: catalin.marinas@arm.com, will.deacon@arm.com,
	Robin Murphy <robin.murphy@arm.com>,
	hch@lst.de, linux-arm-kernel@lists.infradead.org,
	m.szyprowski@samsung.com
Subject: Re: [PATCH] arm64: dma-mapping: Fix FORCE_CONTIGUOUS buffer clearing
Date: Wed, 12 Dec 2018 08:37:03 +0100	[thread overview]
Message-ID: <20181212073703.GA29091@lst.de> (raw)
In-Reply-To: <9f6d3b29-7ca6-c78f-c4b6-f10dd318b1d9@codeaurora.org>

On Wed, Dec 12, 2018 at 01:01:41PM +0530, Chintan Pandya wrote:
>>   		if (addr) {
>> -			memset(addr, 0, size);
>>   			if (!coherent)
>>   				__dma_flush_area(page_to_virt(page), iosize);
>> +			memset(addr, 0, size);
>
> For coherent case, we still skip flushing/invalidating dirty kernel
> mappings. Isn't it a problem ?

For the dma coherent case there is no need to writeback and/or invalidate
the kernel mapping.

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      reply	other threads:[~2018-12-12  7:37 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-12-10 19:33 [PATCH] arm64: dma-mapping: Fix FORCE_CONTIGUOUS buffer clearing Robin Murphy
2018-12-10 19:36 ` Will Deacon
2018-12-11 11:55   ` Catalin Marinas
2018-12-12  7:31 ` Chintan Pandya
2018-12-12  7:37   ` Christoph Hellwig [this message]

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