Re: [PATCH] Revert "mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE"

From: Joonsoo Kim <js1304@gmail.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com>,
	"Laura Abbott" <labbott@redhat.com>,
	"Michal Hocko" <mhocko@kernel.org>,
	"Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>,
	"Tony Lindgren" <tony@atomide.com>,
	"Vlastimil Babka" <vbabka@suse.cz>,
	"Johannes Weiner" <hannes@cmpxchg.org>,
	"Laura Abbott" <lauraa@codeaurora.org>,
	"Marek Szyprowski" <m.szyprowski@samsung.com>,
	"Mel Gorman" <mgorman@techsingularity.net>,
	"Michal Nazarewicz" <mina86@mina86.com>,
	"Minchan Kim" <minchan@kernel.org>,
	"Rik van Riel" <riel@redhat.com>,
	"Russell King" <linux@armlinux.org.uk>,
	"Will Deacon" <will.deacon@arm.com>,
	"Linus Torvalds" <torvalds@linux-foundation.org>,
	"Linux Memory Management List" <linux-mm@kvack.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] Revert "mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE"
Date: Wed, 23 May 2018 09:09:04 +0900	[thread overview]
Message-ID: <CAAmzW4N=r9CwU48Uha66DUH-7A80gjMXLEF7K4kAK=DaZY8nTw@mail.gmail.com> (raw)
In-Reply-To: <20180522170257.ae5387d8717e81def908a53b@linux-foundation.org>

2018-05-23 9:02 GMT+09:00 Andrew Morton <akpm@linux-foundation.org>:
> On Mon, 21 May 2018 15:16:33 +0900 Joonsoo Kim <js1304@gmail.com> wrote:
>
>> > (gdb) list *(dma_direct_alloc+0x22f)
>> > 0x573fbf is in dma_direct_alloc (../lib/dma-direct.c:104).
>> > 94
>> > 95          if (!page)
>> > 96                  return NULL;
>> > 97          ret = page_address(page);
>> > 98          if (force_dma_unencrypted()) {
>> > 99                  set_memory_decrypted((unsigned long)ret, 1 << page_order);
>> > 100                 *dma_handle = __phys_to_dma(dev, page_to_phys(page));
>> > 101         } else {
>> > 102                 *dma_handle = phys_to_dma(dev, page_to_phys(page));
>> > 103         }
>> > 104         memset(ret, 0, size);
>> > 105         return ret;
>> > 106 }
>> >
>>
>> Okay. I find the reason about this error.
>
> It's getting rather late and we don't seem to have a final set of fixes
> yet.  Perhaps the best approach here is to revert and try again for
> 4.18?

Yes. Reverting seems to be a right decision at this moment.
Could you apply original revert patch from Ville?

Thanks.