linux-kernel - [ 110/117] i2c: tegra: notify transfer-complete after clearing status.

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:	Mon, 28 May 2012 04:13:52 +0100
From:	Ben Hutchings <ben@...adent.org.uk>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:	torvalds@...ux-foundation.org, akpm@...ux-foundation.org,
	alan@...rguk.ukuu.org.uk, Laxman Dewangan <ldewangan@...dia.com>,
	Stephen Warren <swarren@...dotorg.org>,
	Wolfram Sang <w.sang@...gutronix.de>
Subject: [ 110/117] i2c: tegra: notify transfer-complete after clearing status.

3.2-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Laxman Dewangan <ldewangan@...dia.com>

commit c889e91d2cc22123f20f40dde0c0a91856a20eea upstream.

The notification of the transfer complete by calling complete()
should be done after clearing all interrupt status.
This avoids the race condition of misconfigure the i2c controller
in multi-core environment.

Signed-off-by: Laxman Dewangan <ldewangan@...dia.com>
Acked-by: Stephen Warren <swarren@...dotorg.org>
Signed-off-by: Wolfram Sang <w.sang@...gutronix.de>
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
 drivers/i2c/busses/i2c-tegra.c |   13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 18067b3..8b2e555 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -401,8 +401,6 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
 			disable_irq_nosync(i2c_dev->irq);
 			i2c_dev->irq_disabled = 1;
 		}
-
-		complete(&i2c_dev->msg_complete);
 		goto err;
 	}
 
@@ -411,7 +409,6 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
 			i2c_dev->msg_err |= I2C_ERR_NO_ACK;
 		if (status & I2C_INT_ARBITRATION_LOST)
 			i2c_dev->msg_err |= I2C_ERR_ARBITRATION_LOST;
-		complete(&i2c_dev->msg_complete);
 		goto err;
 	}
 
@@ -429,14 +426,14 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
 			tegra_i2c_mask_irq(i2c_dev, I2C_INT_TX_FIFO_DATA_REQ);
 	}
 
+	i2c_writel(i2c_dev, status, I2C_INT_STATUS);
+	if (i2c_dev->is_dvc)
+		dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
+
 	if (status & I2C_INT_PACKET_XFER_COMPLETE) {
 		BUG_ON(i2c_dev->msg_buf_remaining);
 		complete(&i2c_dev->msg_complete);
 	}
-
-	i2c_writel(i2c_dev, status, I2C_INT_STATUS);
-	if (i2c_dev->is_dvc)
-		dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
 	return IRQ_HANDLED;
 err:
 	/* An error occurred, mask all interrupts */
@@ -446,6 +443,8 @@ err:
 	i2c_writel(i2c_dev, status, I2C_INT_STATUS);
 	if (i2c_dev->is_dvc)
 		dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
+
+	complete(&i2c_dev->msg_complete);
 	return IRQ_HANDLED;
 }
 


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/