linux-kernel - Re: [PATCH v5 02/25] fs/dax: Return unmapped busy pages from dax_layout_busy_page

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <677efca34ca0b_f58f2943e@dwillia2-xfh.jf.intel.com.notmuch>
Date: Wed, 8 Jan 2025 14:30:59 -0800
From: Dan Williams <dan.j.williams@...el.com>
To: Alistair Popple <apopple@...dia.com>, <akpm@...ux-foundation.org>,
	<dan.j.williams@...el.com>, <linux-mm@...ck.org>
CC: Alistair Popple <apopple@...dia.com>, <lina@...hilina.net>,
	<zhang.lyra@...il.com>, <gerald.schaefer@...ux.ibm.com>,
	<vishal.l.verma@...el.com>, <dave.jiang@...el.com>, <logang@...tatee.com>,
	<bhelgaas@...gle.com>, <jack@...e.cz>, <jgg@...pe.ca>,
	<catalin.marinas@....com>, <will@...nel.org>, <mpe@...erman.id.au>,
	<npiggin@...il.com>, <dave.hansen@...ux.intel.com>, <ira.weiny@...el.com>,
	<willy@...radead.org>, <djwong@...nel.org>, <tytso@....edu>,
	<linmiaohe@...wei.com>, <david@...hat.com>, <peterx@...hat.com>,
	<linux-doc@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
	<linux-arm-kernel@...ts.infradead.org>, <linuxppc-dev@...ts.ozlabs.org>,
	<nvdimm@...ts.linux.dev>, <linux-cxl@...r.kernel.org>,
	<linux-fsdevel@...r.kernel.org>, <linux-ext4@...r.kernel.org>,
	<linux-xfs@...r.kernel.org>, <jhubbard@...dia.com>, <hch@....de>,
	<david@...morbit.com>
Subject: Re: [PATCH v5 02/25] fs/dax: Return unmapped busy pages from
 dax_layout_busy_page_range()

Alistair Popple wrote:
> dax_layout_busy_page_range() is used by file systems to scan the DAX
> page-cache to unmap mapping pages from user-space and to determine if
> any pages in the given range are busy, either due to ongoing DMA or
> other get_user_pages() usage.
> 
> Currently it checks to see the file mapping is mapped into user-space
> with mapping_mapped() and returns early if not, skipping the check for
> DMA busy pages. This is wrong as pages may still be undergoing DMA
> access even if they have subsequently been unmapped from
> user-space. Fix this by dropping the check for mapping_mapped().
> 
> Signed-off-by: Alistair Popple <apopple@...dia.com>
> Suggested-by: Dan Williams <dan.j.williams@...el.com>

Reviewed-by: Dan Williams <dan.j.williams@...el.com>