Hi Mark,
On Dec 9 2017 03:52, Mark Brown wrote:
The patch
ASoC: rsnd: ssi: fix race condition in rsnd_ssi_pointer_update
has been applied to the asoc tree at
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git
The applied patches are in v1 patchset, but we have v2 patchset already:
http://mailman.alsa-project.org/pipermail/alsa-devel/2017-December/128970.html
Would you please replace the applied patches with the renewed ones?
There're slight differences between them.
All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying
to this mail.
Thanks,
Mark
From 33f801366bdf3f8b67dfe325b84f4051a090d01e Mon Sep 17 00:00:00 2001
From: Jiada Wang <jiada_w...@mentor.com>
Date: Thu, 7 Dec 2017 22:15:38 -0800
Subject: [PATCH] ASoC: rsnd: ssi: fix race condition in
rsnd_ssi_pointer_update
Currently there is race condition between set of byte_pos and wrap
it around when new buffer starts. If .pointer is called in-between
it will result in inconsistent pointer position be returned
from .pointer callback.
This patch increments buffer pointer atomically to avoid this issue.
Signed-off-by: Jiada Wang <jiada_w...@mentor.com>
Reviewed-by: Takashi Sakamoto <takashi.sakam...@miraclelinux.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto...@renesas.com>
Signed-off-by: Mark Brown <broo...@kernel.org>
---
sound/soc/sh/rcar/ssi.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/sound/soc/sh/rcar/ssi.c b/sound/soc/sh/rcar/ssi.c
index fece1e5f582f..cbf3bf312d23 100644
--- a/sound/soc/sh/rcar/ssi.c
+++ b/sound/soc/sh/rcar/ssi.c
@@ -446,25 +446,29 @@ static bool rsnd_ssi_pointer_update(struct rsnd_mod *mod,
int byte)
{
struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod);
+ bool ret = false;
+ int byte_pos;
- ssi->byte_pos += byte;
+ byte_pos = ssi->byte_pos + byte;
- if (ssi->byte_pos >= ssi->next_period_byte) {
+ if (byte_pos >= ssi->next_period_byte) {
struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
ssi->period_pos++;
ssi->next_period_byte += ssi->byte_per_period;
if (ssi->period_pos >= runtime->periods) {
- ssi->byte_pos = 0;
+ byte_pos = 0;
ssi->period_pos = 0;
ssi->next_period_byte = ssi->byte_per_period;
}
- return true;
+ ret = true;
}
- return false;
+ WRITE_ONCE(ssi->byte_pos, byte_pos);
+
+ return ret;
}
/*
@@ -838,7 +842,7 @@ static int rsnd_ssi_pointer(struct rsnd_mod *mod,
struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod);
struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
- *pointer = bytes_to_frames(runtime, ssi->byte_pos);
+ *pointer = bytes_to_frames(runtime, READ_ONCE(ssi->byte_pos));
return 0;
}
Thanks
Takashi Sakamoto
