mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Brian Starkey <brian.starkey@arm.com>
To: gregkh@linuxfoundation.org
Cc: catalin.marinas@arm.com, dan.j.williams@intel.com,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: [RESEND PATCH 3/3] drivers: dma-coherent: use memset_io for DMA_MEMORY_IO mappings
Date: Tue,  5 Jan 2016 16:41:28 +0000	[thread overview]
Message-ID: <073de716b49028bbbd819fc403c2532a12992abe.1452010803.git.brian.starkey@arm.com> (raw)
In-Reply-To: <cover.1452010802.git.brian.starkey@arm.com>

Use memset_io() for DMA_MEMORY_IO mappings which are mapped as I/O
memory, and regular memset() for DMA_MEMORY_MAP mappings.

This fixes the below alignment fault on arm64 for DMA_MEMORY_IO
mappings, where memset() uses the DC ZVA instruction which is
invalid on device memory.

   Unhandled fault: alignment fault (0x96000061) at 0xffffff8000380000
   Internal error: : 96000061 [#1] PREEMPT SMP
   Modules linked in: hdlcd(+) clk_scpi
   CPU: 4 PID: 1355 Comm: systemd-udevd Not tainted 4.4.0-rc1+ #5
   Hardware name: ARM Juno development board (r0) (DT)
   task: ffffffc9763eee00 ti: ffffffc9758c4000 task.ti: ffffffc9758c4000
   PC is at __efistub_memset+0x1ac/0x200
   LR is at dma_alloc_from_coherent+0xb0/0x120
   pc : [<ffffffc00030ff2c>] lr : [<ffffffc00042a918>] pstate: 400001c5
   sp : ffffffc9758c79a0
   x29: ffffffc9758c79a0 x28: ffffffc000635cd0
   x27: 0000000000000124 x26: ffffffc000119ef4
   x25: 0000000000010000 x24: 0000000000000140
   x23: ffffffc07e9ac3a8 x22: ffffffc9758c7a58
   x21: ffffffc9758c7a68 x20: 0000000000000004
   x19: ffffffc07e9ac380 x18: 0000000000000001
   x17: 0000007fae1bbba8 x16: ffffffc0001b2d1c
   x15: ffffffffffffffff x14: 0ffffffffffffffe
   x13: 0000000000000010 x12: ffffff800837ffff
   x11: ffffff800837ffff x10: 0000000040000000
   x9 : 0000000000000000 x8 : ffffff8000380000
   x7 : 0000000000000000 x6 : 000000000000003f
   x5 : 0000000000000040 x4 : 0000000000000000
   x3 : 0000000000000004 x2 : 000000000000ffc0
   x1 : 0000000000000000 x0 : ffffff8000380000

Signed-off-by: Brian Starkey <brian.starkey@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
---
 drivers/base/dma-coherent.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c
index f98359a..4e4ad30 100644
--- a/drivers/base/dma-coherent.c
+++ b/drivers/base/dma-coherent.c
@@ -193,7 +193,10 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size,
 	 */
 	*dma_handle = mem->device_base + (pageno << PAGE_SHIFT);
 	*ret = mem->virt_base + (pageno << PAGE_SHIFT);
-	memset(*ret, 0, size);
+	if (mem->flags & DMA_MEMORY_MAP)
+		memset(*ret, 0, size);
+	else
+		memset_io(*ret, 0, size);
 	spin_unlock_irqrestore(&mem->spinlock, flags);
 
 	return 1;
-- 
1.7.9.5


  parent reply	other threads:[~2016-01-05 16:42 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-01-05 16:41 [RESEND PATCH 0/3] Add MEMREMAP_WC to fix dma_init_coherent_memory Brian Starkey
2016-01-05 16:41 ` [RESEND PATCH 1/3] memremap: add MEMREMAP_WC flag Brian Starkey
2016-01-05 16:41 ` [RESEND PATCH 2/3] drivers: dma-coherent: use MEMREMAP_WC for DMA_MEMORY_MAP Brian Starkey
2016-01-05 19:02   ` Michal Nazarewicz
2016-01-05 16:41 ` Brian Starkey [this message]
2016-01-29  9:32 ` [RESEND PATCH 0/3] Add MEMREMAP_WC to fix dma_init_coherent_memory Brian Starkey

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=073de716b49028bbbd819fc403c2532a12992abe.1452010803.git.brian.starkey@arm.com \
    --to=brian.starkey@arm.com \
    --cc=catalin.marinas@arm.com \
    --cc=dan.j.williams@intel.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome