lkml.org 
[lkml]   [2020]   [Jun]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 1/2] spi: spi-fsl-dspi: Fix external abort on interrupt in exit paths
Date
If interrupt comes late, during probe error path or device remove (could
be triggered with CONFIG_DEBUG_SHIRQ), the interrupt handler
dspi_interrupt() will access registers with the clock being disabled. This
leads to external abort on non-linefetch on Toradex Colibri VF50 module
(with Vybrid VF5xx):

$ echo 4002d000.spi > /sys/devices/platform/soc/40000000.bus/4002d000.spi/driver/unbind

Unhandled fault: external abort on non-linefetch (0x1008) at 0x8887f02c
Internal error: : 1008 [#1] ARM
CPU: 0 PID: 136 Comm: sh Not tainted 5.7.0-next-20200610-00009-g5c913fa0f9c5-dirty #74
Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree)
(regmap_mmio_read32le) from [<8061885c>] (regmap_mmio_read+0x48/0x68)
(regmap_mmio_read) from [<8060e3b8>] (_regmap_bus_reg_read+0x24/0x28)
(_regmap_bus_reg_read) from [<80611c50>] (_regmap_read+0x70/0x1c0)
(_regmap_read) from [<80611dec>] (regmap_read+0x4c/0x6c)
(regmap_read) from [<80678ca0>] (dspi_interrupt+0x3c/0xa8)
(dspi_interrupt) from [<8017acec>] (free_irq+0x26c/0x3cc)
(free_irq) from [<8017dcec>] (devm_irq_release+0x1c/0x20)
(devm_irq_release) from [<805f98ec>] (release_nodes+0x1e4/0x298)
(release_nodes) from [<805f9ac8>] (devres_release_all+0x40/0x60)
(devres_release_all) from [<805f5134>] (device_release_driver_internal+0x108/0x1ac)
(device_release_driver_internal) from [<805f521c>] (device_driver_detach+0x20/0x24)

The resource-managed framework should not be used for interrupt handling,
because the resource will be released too late - after disabling clocks.
The interrupt handler is not prepared for such case.

Fixes: 349ad66c0ab0 ("spi:Add Freescale DSPI driver for Vybrid VF610 platform")
Cc: <stable@vger.kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>

---

This is an follow up of my other patch for I2C IMX driver [1]. Let's fix the
issues consistently.

[1] https://lore.kernel.org/lkml/1592130544-19759-2-git-send-email-krzk@kernel.org/T/#u
---
drivers/spi/spi-fsl-dspi.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c
index 58190c94561f..57e7a626ba00 100644
--- a/drivers/spi/spi-fsl-dspi.c
+++ b/drivers/spi/spi-fsl-dspi.c
@@ -1385,8 +1385,8 @@ static int dspi_probe(struct platform_device *pdev)
goto poll_mode;
}

- ret = devm_request_irq(&pdev->dev, dspi->irq, dspi_interrupt,
- IRQF_SHARED, pdev->name, dspi);
+ ret = request_threaded_irq(dspi->irq, dspi_interrupt, NULL,
+ IRQF_SHARED, pdev->name, dspi);
if (ret < 0) {
dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n");
goto out_clk_put;
@@ -1400,7 +1400,7 @@ static int dspi_probe(struct platform_device *pdev)
ret = dspi_request_dma(dspi, res->start);
if (ret < 0) {
dev_err(&pdev->dev, "can't get dma channels\n");
- goto out_clk_put;
+ goto out_free_irq;
}
}

@@ -1415,11 +1415,14 @@ static int dspi_probe(struct platform_device *pdev)
ret = spi_register_controller(ctlr);
if (ret != 0) {
dev_err(&pdev->dev, "Problem registering DSPI ctlr\n");
- goto out_clk_put;
+ goto out_free_irq;
}

return ret;

+out_free_irq:
+ if (dspi->irq > 0)
+ free_irq(dspi->irq, dspi);
out_clk_put:
clk_disable_unprepare(dspi->clk);
out_ctlr_put:
@@ -1435,6 +1438,8 @@ static int dspi_remove(struct platform_device *pdev)

/* Disconnect from the SPI framework */
dspi_release_dma(dspi);
+ if (dspi->irq > 0)
+ free_irq(dspi->irq, dspi);
clk_disable_unprepare(dspi->clk);
spi_unregister_controller(dspi->ctlr);

--
2.7.4
\
 
 \ /
  Last update: 2020-06-14 12:56    [W:1.688 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site