From: "Rafael J. Wysocki" <[email protected]>
If acpi_dev_get_resources() returns overlapping I/O or memory resources,
the subsequent registration of a platform device will fail with -EBUSY
due to a resource conflict. This is reported to happen on Acer Aspire
ES1-572 [1].
Avoid that by adjusting resources returned by acpi_dev_get_resources()
to eliminate partial overlaps between them.
This has not been regarded as necessary before because putting
overlapping resources into the _CRS of one device is really pointless,
but now that the issue has been reported to actually happen in the
field, it needs to be done.
Fixes: ab06eb920401 ("ACPI: scan: Register platform devices for fixed event
buttons")
Reported-by: Julien <[email protected]>
Closes:
https://lore.kernel.org/linux-integrity/cajogg3z6ljpdsdpnbxajgy8_wqxfhybrxe4eiurzf3kpu5a...@mail.gmail.com/
[1]
Cc: All applicable <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
---
v2 -> v3:
* Use resource_union() and adjust code and comment (Andy)
* Include ioport.h directly
v1 -> v2:
* Add the expanded resource instead of and not in addition to the other
overlapping one (Sashiko)
---
drivers/acpi/acpi_platform.c | 39 +++++++++++++++++++++++++++++++++++++--
1 file changed, 37 insertions(+), 2 deletions(-)
--- a/drivers/acpi/acpi_platform.c
+++ b/drivers/acpi/acpi_platform.c
@@ -12,6 +12,7 @@
#include <linux/bits.h>
#include <linux/device.h>
#include <linux/err.h>
+#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/dma-mapping.h>
@@ -71,6 +72,36 @@ static struct notifier_block acpi_platfo
.notifier_call = acpi_platform_device_remove_notify,
};
+static unsigned int acpi_platform_adjust_resources(struct acpi_device *adev,
+ struct resource *new_res,
+ struct resource *resources,
+ unsigned int count)
+{
+ unsigned int i;
+
+ if (!(new_res->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
+ return count;
+
+ for (i = 0; i < count; ) {
+ struct resource *res = &resources[i];
+
+ if (resource_type(new_res) != resource_type(res) ||
+ !resource_union(new_res, res, new_res)) {
+ i++;
+ continue;
+ }
+
+ dev_info(&adev->dev, "%pR expanded to avoid overlap\n",
new_res);
+ /*
+ * Eliminate the previously processed resource that overlapped
+ * with the new one because it is not necessary any more.
+ */
+ memmove(res, res + 1, (--count - i) * sizeof(*res));
+ }
+
+ return count;
+}
+
static void acpi_platform_fill_resource(struct acpi_device *adev,
const struct resource *src, struct resource *dest)
{
@@ -151,10 +182,14 @@ struct platform_device *acpi_create_plat
return ERR_PTR(-ENOMEM);
}
count = 0;
- list_for_each_entry(rentry, &resource_list, node)
+ list_for_each_entry(rentry, &resource_list, node) {
+ count = acpi_platform_adjust_resources(adev,
+
rentry->res,
+
resources,
+ count);
acpi_platform_fill_resource(adev, rentry->res,
&resources[count++]);
-
+ }
acpi_dev_free_resource_list(&resource_list);
}
}