From: Alexander Stein alexander.stein@ew.tq-group.com
[ Upstream commit 4268254a39484fc11ba991ae148bacbe75d9cc0a ]
Instead of repeatedly calling clk_get_rate for each transfer, lock the clock rate and cache the value. A deadlock has been observed while adding tlv320aic32x4 audio codec to the system. When this clock provider adds its clock, the clk mutex is locked already, it needs to access i2c, which in return needs the mutex for clk_get_rate as well.
Signed-off-by: Alexander Stein alexander.stein@ew.tq-group.com Reviewed-by: Uwe Kleine-König u.kleine-koenig@pengutronix.de Reviewed-by: Andi Shyti andi.shyti@kernel.org Signed-off-by: Andi Shyti andi.shyti@kernel.org [ Resolve minor conflicts to fix CVE-2024-40965 ] Signed-off-by: Bin Lan bin.lan.cn@windriver.com --- drivers/i2c/busses/i2c-imx-lpi2c.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c index 678b30e90492..5d4f04a3c6d3 100644 --- a/drivers/i2c/busses/i2c-imx-lpi2c.c +++ b/drivers/i2c/busses/i2c-imx-lpi2c.c @@ -99,6 +99,7 @@ struct lpi2c_imx_struct { __u8 *rx_buf; __u8 *tx_buf; struct completion complete; + unsigned long rate_per; unsigned int msglen; unsigned int delivered; unsigned int block_data; @@ -207,9 +208,7 @@ static int lpi2c_imx_config(struct lpi2c_imx_struct *lpi2c_imx)
lpi2c_imx_set_mode(lpi2c_imx);
- clk_rate = clk_get_rate(lpi2c_imx->clks[0].clk); - if (!clk_rate) - return -EINVAL; + clk_rate = lpi2c_imx->rate_per;
if (lpi2c_imx->mode == HS || lpi2c_imx->mode == ULTRA_FAST) filt = 0; @@ -590,6 +589,11 @@ static int lpi2c_imx_probe(struct platform_device *pdev) if (ret) return ret;
+ lpi2c_imx->rate_per = clk_get_rate(lpi2c_imx->clks[0].clk); + if (!lpi2c_imx->rate_per) + return dev_err_probe(&pdev->dev, -EINVAL, + "can't get I2C peripheral clock rate\n"); + pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT); pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_get_noresume(&pdev->dev);
[ Sasha's backport helper bot ]
Hi,
The upstream commit SHA1 provided is correct: 4268254a39484fc11ba991ae148bacbe75d9cc0a
WARNING: Author mismatch between patch and upstream commit: Backport author: Bin Lan bin.lan.cn@windriver.com Commit author: Alexander Stein alexander.stein@ew.tq-group.com
Status in newer kernel trees: 6.12.y | Present (exact SHA1) 6.11.y | Present (exact SHA1) 6.6.y | Not found
Note: The patch differs from the upstream commit: --- --- - 2024-11-20 22:14:04.767206166 -0500 +++ /tmp/tmp.dfA5216Jw0 2024-11-20 22:14:04.757393564 -0500 @@ -1,3 +1,5 @@ +[ Upstream commit 4268254a39484fc11ba991ae148bacbe75d9cc0a ] + Instead of repeatedly calling clk_get_rate for each transfer, lock the clock rate and cache the value. A deadlock has been observed while adding tlv320aic32x4 audio codec to @@ -9,12 +11,14 @@ Reviewed-by: Uwe Kleine-König u.kleine-koenig@pengutronix.de Reviewed-by: Andi Shyti andi.shyti@kernel.org Signed-off-by: Andi Shyti andi.shyti@kernel.org +[ Resolve minor conflicts to fix CVE-2024-40965 ] +Signed-off-by: Bin Lan bin.lan.cn@windriver.com --- - drivers/i2c/busses/i2c-imx-lpi2c.c | 19 ++++++++++++++++--- - 1 file changed, 16 insertions(+), 3 deletions(-) + drivers/i2c/busses/i2c-imx-lpi2c.c | 10 +++++++--- + 1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c -index 6d72e4e126dde..36e8f6196a87b 100644 +index 678b30e90492..5d4f04a3c6d3 100644 --- a/drivers/i2c/busses/i2c-imx-lpi2c.c +++ b/drivers/i2c/busses/i2c-imx-lpi2c.c @@ -99,6 +99,7 @@ struct lpi2c_imx_struct { @@ -25,7 +29,7 @@ unsigned int msglen; unsigned int delivered; unsigned int block_data; -@@ -212,9 +213,7 @@ static int lpi2c_imx_config(struct lpi2c_imx_struct *lpi2c_imx) +@@ -207,9 +208,7 @@ static int lpi2c_imx_config(struct lpi2c_imx_struct *lpi2c_imx)
lpi2c_imx_set_mode(lpi2c_imx);
@@ -36,19 +40,10 @@
if (lpi2c_imx->mode == HS || lpi2c_imx->mode == ULTRA_FAST) filt = 0; -@@ -611,6 +610,20 @@ static int lpi2c_imx_probe(struct platform_device *pdev) +@@ -590,6 +589,11 @@ static int lpi2c_imx_probe(struct platform_device *pdev) if (ret) return ret;
-+ /* -+ * Lock the parent clock rate to avoid getting parent clock upon -+ * each transfer -+ */ -+ ret = devm_clk_rate_exclusive_get(&pdev->dev, lpi2c_imx->clks[0].clk); -+ if (ret) -+ return dev_err_probe(&pdev->dev, ret, -+ "can't lock I2C peripheral clock rate\n"); -+ + lpi2c_imx->rate_per = clk_get_rate(lpi2c_imx->clks[0].clk); + if (!lpi2c_imx->rate_per) + return dev_err_probe(&pdev->dev, -EINVAL, @@ -57,3 +52,6 @@ pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT); pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_get_noresume(&pdev->dev); +-- +2.43.0 + ---
Results of testing on various branches:
| Branch | Patch Apply | Build Test | |---------------------------|-------------|------------| | stable/linux-6.6.y | Success | Success |
linux-stable-mirror@lists.linaro.org
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Bin Lan -
Sasha Levin