Patch "mfd: fsl-imx25: Clean up irq settings during removal" has been added to the 4.9-stable tree

Patch "mfd: fsl-imx25: Clean up irq settings during removal" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    mfd: fsl-imx25: Clean up irq settings during removal

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     mfd-fsl-imx25-clean-up-irq-settings-during-removal.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 18f77393796848e68909e65d692c1d1436f06e06 Mon Sep 17 00:00:00 2001
From: Martin Kaiser <martin@kaiser.cx>
Date: Tue, 17 Oct 2017 22:53:08 +0200
Subject: mfd: fsl-imx25: Clean up irq settings during removal

From: Martin Kaiser <martin@kaiser.cx>

commit 18f77393796848e68909e65d692c1d1436f06e06 upstream.

When fsl-imx25-tsadc is compiled as a module, loading, unloading and
reloading the module will lead to a crash.

Unable to handle kernel paging request at virtual address bf005430
[<c004df6c>] (irq_find_matching_fwspec)
   from [<c028d5ec>] (of_irq_get+0x58/0x74)
[<c028d594>] (of_irq_get)
   from [<c01ff970>] (platform_get_irq+0x48/0xc8)
[<c01ff928>] (platform_get_irq)
   from [<bf00e33c>] (mx25_tsadc_probe+0x220/0x2f4 [fsl_imx25_tsadc])

irq_find_matching_fwspec() loops over all registered irq domains. The
irq domain is still registered from last time the module was loaded but
the pointer to its operations is invalid after the module was unloaded.

Add a removal function which clears the irq handler and removes the irq
domain. With this cleanup in place, it's possible to unload and reload
the module.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/mfd/fsl-imx25-tsadc.c |   14 ++++++++++++++
 1 file changed, 14 insertions(+)

--- a/drivers/mfd/fsl-imx25-tsadc.c
+++ b/drivers/mfd/fsl-imx25-tsadc.c
@@ -183,6 +183,19 @@ static int mx25_tsadc_probe(struct platf
 	return 0;
 }
 
+static int mx25_tsadc_remove(struct platform_device *pdev)
+{
+	struct mx25_tsadc *tsadc = platform_get_drvdata(pdev);
+	int irq = platform_get_irq(pdev, 0);
+
+	if (irq) {
+		irq_set_chained_handler_and_data(irq, NULL, NULL);
+		irq_domain_remove(tsadc->domain);
+	}
+
+	return 0;
+}
+
 static const struct of_device_id mx25_tsadc_ids[] = {
 	{ .compatible = "fsl,imx25-tsadc" },
 	{ /* Sentinel */ }
@@ -194,6 +207,7 @@ static struct platform_driver mx25_tsadc
 		.of_match_table = of_match_ptr(mx25_tsadc_ids),
 	},
 	.probe = mx25_tsadc_probe,
+	.remove = mx25_tsadc_remove,
 };
 module_platform_driver(mx25_tsadc_driver);
 


Patches currently in stable-queue which might be from martin@kaiser.cx are

queue-4.9/mfd-fsl-imx25-clean-up-irq-settings-during-removal.patch