Linux-mm Archive on lore.kernel.org
 help / color / Atom feed
From: Andrew Morton <akpm@linux-foundation.org>
To: akpm@linux-foundation.org, hch@lst.de, linux-mm@kvack.org,
	linux@armlinux.org.uk, mm-commits@vger.kernel.org,
	robin.murphy@arm.com, stable@vger.kernel.org,
	torvalds@linux-foundation.org, wens@csie.org
Subject: [patch 67/67] ARM: dma-api: fix max_pfn off-by-one error in __dma_supported()
Date: Mon, 03 Feb 2020 17:37:48 -0800
Message-ID: <20200204013748.ezp0xXg5F%akpm@linux-foundation.org> (raw)
In-Reply-To: <20200203173311.6269a8be06a05e5a4aa08a93@linux-foundation.org>

From: Chen-Yu Tsai <wens@csie.org>
Subject: ARM: dma-api: fix max_pfn off-by-one error in __dma_supported()

max_pfn, as set in arch/arm/mm/init.c:

    static void __init find_limits(unsigned long *min,
				   unsigned long *max_low,
				   unsigned long *max_high)
    {
	    *max_low = PFN_DOWN(memblock_get_current_limit());
	    *min = PFN_UP(memblock_start_of_DRAM());
	    *max_high = PFN_DOWN(memblock_end_of_DRAM());
    }

with memblock_end_of_DRAM() pointing to the next byte after DRAM.  As
such, max_pfn points to the PFN after the end of DRAM.

Thus when using max_pfn to check DMA masks, we should subtract one when
checking DMA ranges against it.

Commit 8bf1268f48ad ("ARM: dma-api: fix off-by-one error in
__dma_supported()") fixed the same issue, but missed this spot.

This issue was found while working on the sun4i-csi v4l2 driver on the
Allwinner R40 SoC.  On Allwinner SoCs, DRAM is offset at 0x40000000, and
we are starting to use of_dma_configure() with the "dma-ranges" property
in the device tree to have the DMA API handle the offset.

In this particular instance, dma-ranges was set to the same range as the
actual available (2 GiB) DRAM.  The following error appeared when the
driver attempted to allocate a buffer:

    sun4i-csi 1c09000.csi: Coherent DMA mask 0x7fffffff (pfn 0x40000-0xc0000)
    covers a smaller range of system memory than the DMA zone pfn 0x0-0xc0001
    sun4i-csi 1c09000.csi: dma_alloc_coherent of size 307200 failed

Fixing the off-by-one error makes things work.

Link: http://lkml.kernel.org/r/20191224030239.5656-1-wens@kernel.org
Fixes: 11a5aa32562e ("ARM: dma-mapping: check DMA mask against available memory")
Fixes: 9f28cde0bc64 ("ARM: another fix for the DMA mapping checks")
Fixes: ab746573c405 ("ARM: dma-mapping: allow larger DMA mask than supported")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/arm/mm/dma-mapping.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/arm/mm/dma-mapping.c~arm-dma-api-fix-max_pfn-off-by-one-error-in-__dma_supported
+++ a/arch/arm/mm/dma-mapping.c
@@ -221,7 +221,7 @@ EXPORT_SYMBOL(arm_coherent_dma_ops);
 
 static int __dma_supported(struct device *dev, u64 mask, bool warn)
 {
-	unsigned long max_dma_pfn = min(max_pfn, arm_dma_pfn_limit);
+	unsigned long max_dma_pfn = min(max_pfn - 1, arm_dma_pfn_limit);
 
 	/*
 	 * Translate the device's DMA mask to a PFN limit.  This
_


  parent reply index

Thread overview: 95+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-04  1:33 incoming Andrew Morton
2020-02-04  1:33 ` [patch 01/67] ocfs2: fix oops when writing cloned file Andrew Morton
2020-02-04  1:33 ` [patch 02/67] mm/page_alloc.c: fix uninitialized memmaps on a partially populated last section Andrew Morton
2020-02-04  1:33 ` [patch 03/67] fs/proc/page.c: allow inspection of last section and fix end detection Andrew Morton
2020-02-04  1:33 ` [patch 04/67] mm/page_alloc.c: initialize memmap of unavailable memory directly Andrew Morton
2020-02-04  1:33 ` [patch 05/67] mm/page_alloc: fix and rework pfn handling in memmap_init_zone() Andrew Morton
2020-02-04  2:45   ` Linus Torvalds
2020-02-04  1:34 ` [patch 06/67] mm: factor out next_present_section_nr() Andrew Morton
2020-02-04  3:04   ` Linus Torvalds
2020-02-04  4:29     ` Andrew Morton
2020-02-04  8:22     ` David Hildenbrand
2020-02-04  1:34 ` [patch 07/67] mm/memmap_init: update variable name in memmap_init_zone Andrew Morton
2020-02-04  1:34 ` [patch 08/67] mm/memory_hotplug: poison memmap in remove_pfn_range_from_zone() Andrew Morton
2020-02-04  1:34 ` [patch 09/67] mm/memory_hotplug: we always have a zone in find_(smallest|biggest)_section_pfn Andrew Morton
2020-02-04  1:34 ` [patch 10/67] mm/memory_hotplug: don't check for "all holes" in shrink_zone_span() Andrew Morton
2020-02-04  1:34 ` [patch 11/67] mm/memory_hotplug: drop local variables " Andrew Morton
2020-02-04  1:34 ` [patch 12/67] mm/memory_hotplug: cleanup __remove_pages() Andrew Morton
2020-02-04  1:34 ` [patch 13/67] mm/memory_hotplug: drop valid_start/valid_end from test_pages_in_a_zone() Andrew Morton
2020-02-04  1:34 ` [patch 14/67] smp_mb__{before,after}_atomic(): update Documentation Andrew Morton
2020-02-04  1:34 ` [patch 15/67] ipc/mqueue.c: remove duplicated code Andrew Morton
2020-02-04  1:34 ` [patch 16/67] ipc/mqueue.c: update/document memory barriers Andrew Morton
2020-02-04  1:34 ` [patch 17/67] ipc/msg.c: update and document " Andrew Morton
2020-02-04  1:34 ` [patch 18/67] ipc/sem.c: document and update " Andrew Morton
2020-02-04  1:34 ` [patch 19/67] ipc/msg.c: consolidate all xxxctl_down() functions Andrew Morton
2020-02-04  1:34 ` [patch 20/67] drivers/block/null_blk_main.c: fix layout Andrew Morton
2020-02-04  1:34 ` [patch 21/67] drivers/block/null_blk_main.c: fix uninitialized var warnings Andrew Morton
2020-02-04  1:34 ` [patch 22/67] pinctrl: fix pxa2xx.c build warnings Andrew Morton
2020-02-04  1:34 ` [patch 23/67] mm: remove __krealloc Andrew Morton
2020-02-04  1:35 ` [patch 24/67] mm: add generic p?d_leaf() macros Andrew Morton
2020-02-04  1:35 ` [patch 25/67] arc: mm: add p?d_leaf() definitions Andrew Morton
2020-02-04  1:35 ` [patch 26/67] arm: " Andrew Morton
2020-02-04  1:35 ` [patch 27/67] arm64: " Andrew Morton
2020-02-04  1:35 ` [patch 28/67] mips: " Andrew Morton
2020-02-04  1:35 ` [patch 29/67] powerpc: " Andrew Morton
2020-02-04  1:35 ` [patch 30/67] riscv: " Andrew Morton
2020-02-04  1:35 ` [patch 31/67] s390: " Andrew Morton
2020-02-04  1:35 ` [patch 32/67] sparc: " Andrew Morton
2020-02-04  1:35 ` [patch 33/67] x86: " Andrew Morton
2020-02-04  1:35 ` [patch 34/67] mm: pagewalk: add p4d_entry() and pgd_entry() Andrew Morton
2020-02-04  1:35 ` [patch 35/67] mm: pagewalk: allow walking without vma Andrew Morton
2020-02-04  1:35 ` [patch 36/67] mm: pagewalk: don't lock PTEs for walk_page_range_novma() Andrew Morton
2020-02-04  1:35 ` [patch 37/67] mm: pagewalk: fix termination condition in walk_pte_range() Andrew Morton
2020-02-04  1:36 ` [patch 38/67] mm: pagewalk: add 'depth' parameter to pte_hole Andrew Morton
2020-02-04  1:36 ` [patch 39/67] x86: mm: point to struct seq_file from struct pg_state Andrew Morton
2020-02-04  1:36 ` [patch 40/67] x86: mm+efi: convert ptdump_walk_pgd_level() to take a mm_struct Andrew Morton
2020-02-04  1:36 ` [patch 41/67] x86: mm: convert ptdump_walk_pgd_level_debugfs() to take an mm_struct Andrew Morton
2020-02-04  1:36 ` [patch 42/67] mm: add generic ptdump Andrew Morton
2020-02-04  1:36 ` [patch 43/67] x86: mm: convert dump_pagetables to use walk_page_range Andrew Morton
2020-02-04  1:36 ` [patch 44/67] arm64: mm: convert mm/dump.c to use walk_page_range() Andrew Morton
2020-02-04  1:36 ` [patch 45/67] arm64: mm: display non-present entries in ptdump Andrew Morton
2020-02-04  1:36 ` [patch 46/67] mm: ptdump: reduce level numbers by 1 in note_page() Andrew Morton
2020-02-04  1:36 ` [patch 47/67] x86: mm: avoid allocating struct mm_struct on the stack Andrew Morton
2020-02-04  1:36 ` [patch 48/67] powerpc/mmu_gather: enable RCU_TABLE_FREE even for !SMP case Andrew Morton
2020-02-04  1:36 ` [patch 49/67] mm/mmu_gather: invalidate TLB correctly on batch allocation failure and flush Andrew Morton
2020-02-04  1:36 ` [patch 50/67] asm-generic/tlb: avoid potential double flush Andrew Morton
2020-02-04  1:36 ` [patch 51/67] asm-gemeric/tlb: remove stray function declarations Andrew Morton
2020-02-04  1:36 ` [patch 52/67] asm-generic/tlb: add missing CONFIG symbol Andrew Morton
2020-02-04  1:37 ` [patch 53/67] asm-generic/tlb: rename HAVE_RCU_TABLE_FREE Andrew Morton
2020-02-04  1:37 ` [patch 54/67] asm-generic/tlb: rename HAVE_MMU_GATHER_PAGE_SIZE Andrew Morton
2020-02-04  1:37 ` [patch 55/67] asm-generic/tlb: rename HAVE_MMU_GATHER_NO_GATHER Andrew Morton
2020-02-04  1:37 ` [patch 56/67] asm-generic/tlb: provide MMU_GATHER_TABLE_FREE Andrew Morton
2020-02-04  1:37 ` [patch 57/67] proc: decouple proc from VFS with "struct proc_ops" Andrew Morton
2020-02-04  1:37 ` [patch 58/67] proc: convert everything to " Andrew Morton
2020-02-04  1:37 ` [patch 59/67] lib/string: add strnchrnul() Andrew Morton
2020-02-04  1:37 ` [patch 60/67] bitops: more BITS_TO_* macros Andrew Morton
2020-02-04  1:37 ` [patch 61/67] lib: add test for bitmap_parse() Andrew Morton
2020-02-04  1:37 ` [patch 62/67] lib: make bitmap_parse_user a wrapper on bitmap_parse Andrew Morton
2020-02-04  1:37 ` [patch 63/67] lib: rework bitmap_parse() Andrew Morton
2020-02-04  1:37 ` [patch 64/67] lib: new testcases for bitmap_parse{_user} Andrew Morton
2020-02-04  1:37 ` [patch 65/67] include/linux/cpumask.h: don't calculate length of the input string Andrew Morton
2020-02-04  1:37 ` [patch 66/67] treewide: remove redundant IS_ERR() before error code check Andrew Morton
2020-02-04  1:37 ` Andrew Morton [this message]
2020-02-04  2:27 ` incoming Linus Torvalds
2020-02-04  2:46   ` incoming Andrew Morton
2020-02-04  3:11     ` incoming Linus Torvalds
2020-02-14  6:26 ` mmotm 2020-02-13-22-26 uploaded Andrew Morton
2020-02-14 16:29   ` mmotm 2020-02-13-22-26 uploaded (mm/hugetlb.c) Randy Dunlap
2020-02-14 17:18     ` Mike Kravetz
2020-02-14 20:51       ` Mina Almasry
     [not found]       ` <20200214204544.231482-1-almasrymina@google.com>
2020-02-14 21:00         ` [PATCH] hugetlb: fix CONFIG_CGROUP_HUGETLB ifdefs Mina Almasry
2020-02-15  1:17           ` Randy Dunlap
2020-02-15  1:56             ` Randy Dunlap
2020-02-16 20:40               ` Mina Almasry
2020-02-16 21:03                 ` Mina Almasry
2020-02-17  2:48                   ` Randy Dunlap
2020-02-17  2:57                     ` [PATCH] hugetlb: fix <linux/hugetlb_cgroup.h> structs Randy Dunlap
2020-02-17  3:53               ` [PATCH] hugetlb: fix CONFIG_CGROUP_HUGETLB ifdefs Stephen Rothwell
2020-02-14 16:49   ` mmotm 2020-02-13-22-26 uploaded (mm/migrate.c, hugetlb_cgroup.h) Randy Dunlap
2020-02-25  3:53 ` mmotm 2020-02-24-19-53 uploaded Andrew Morton
2020-02-25  6:16   ` mmotm 2020-02-24-19-53 uploaded (init/main.c: initrd*) Randy Dunlap
2020-02-25  6:18     ` Randy Dunlap
2020-02-25  6:21       ` Randy Dunlap
2020-02-25 16:41   ` mmotm 2020-02-24-19-53 uploaded (drivers/platform/x86/intel_pmc_core.c) Randy Dunlap
2020-02-25 17:01   ` mmotm 2020-02-24-19-53 uploaded (objtool warning) Randy Dunlap
2020-02-27 21:52     ` Josh Poimboeuf

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=20200204013748.ezp0xXg5F%akpm@linux-foundation.org \
    --to=akpm@linux-foundation.org \
    --cc=hch@lst.de \
    --cc=linux-mm@kvack.org \
    --cc=linux@armlinux.org.uk \
    --cc=mm-commits@vger.kernel.org \
    --cc=robin.murphy@arm.com \
    --cc=stable@vger.kernel.org \
    --cc=torvalds@linux-foundation.org \
    --cc=wens@csie.org \
    /path/to/YOUR_REPLY

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

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-mm Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-mm/0 linux-mm/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-mm linux-mm/ https://lore.kernel.org/linux-mm \
		linux-mm@kvack.org
	public-inbox-index linux-mm

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kvack.linux-mm


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git