[irqchip: irq/irqchip-fixes] irqchip/gicv3: Handle resource request failure consistently

From: irqchip-bot for Robin Murphy
Date: Thu Jun 16 2022 - 13:17:39 EST


The following commit has been merged into the irq/irqchip-fixes branch of irqchip:

Commit-ID: 4deb96e35c5c3ebfeb9cf567f3ba80fa54e2cec1
Gitweb: https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms/4deb96e35c5c3ebfeb9cf567f3ba80fa54e2cec1
Author: Robin Murphy <robin.murphy@xxxxxxx>
AuthorDate: Thu, 16 Jun 2022 14:46:46 +01:00
Committer: Marc Zyngier <maz@xxxxxxxxxx>
CommitterDate: Thu, 16 Jun 2022 16:55:59 +01:00

irqchip/gicv3: Handle resource request failure consistently

Due to a silly oversight on my part, making the simple switch to
of_io_request_and_map() in the DT path inadvertently introduced
divergent behaviour, whereby failng to request an iomem region now
becomes fatal for DT, vs. being silently ignored for ACPI.

Refactor a bit harder, so that request errors are non-fatal in both
paths as intended, but also consistently reported as well.

Reported-by: Matt Ranostay <mranostay@xxxxxx>
Fixes: 2b2cd74a06c3 ("irqchip/gic-v3: Claim iomem resources")
Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Link: https://lore.kernel.org/r/5f2b57a0131f3082fae9d3002d360bf784ccb092.1655387206.git.robin.murphy@xxxxxxx
---
drivers/irqchip/irq-gic-v3.c | 41 ++++++++++++++++++++++++++---------
1 file changed, 31 insertions(+), 10 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 5c1cf90..2d25bca 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -2042,15 +2042,40 @@ static void __init gic_of_setup_kvm_info(struct device_node *node)
vgic_set_kvm_info(&gic_v3_kvm_info);
}

+static void gic_request_region(resource_size_t base, resource_size_t size,
+ const char *name)
+{
+ if (!request_mem_region(base, size, name))
+ pr_warn_once(FW_BUG "%s region %pa has overlapping address\n",
+ name, &base);
+}
+
+static void __iomem *gic_of_iomap(struct device_node *node, int idx,
+ const char *name, struct resource *res)
+{
+ void __iomem *base;
+ int ret;
+
+ ret = of_address_to_resource(node, idx, res);
+ if (ret)
+ return IOMEM_ERR_PTR(ret);
+
+ gic_request_region(res->start, resource_size(res), name);
+ base = of_iomap(node, idx);
+
+ return base ?: IOMEM_ERR_PTR(-ENOMEM);
+}
+
static int __init gic_of_init(struct device_node *node, struct device_node *parent)
{
void __iomem *dist_base;
struct redist_region *rdist_regs;
+ struct resource res;
u64 redist_stride;
u32 nr_redist_regions;
int err, i;

- dist_base = of_io_request_and_map(node, 0, "GICD");
+ dist_base = gic_of_iomap(node, 0, "GICD", &res);
if (IS_ERR(dist_base)) {
pr_err("%pOF: unable to map gic dist registers\n", node);
return PTR_ERR(dist_base);
@@ -2073,12 +2098,8 @@ static int __init gic_of_init(struct device_node *node, struct device_node *pare
}

for (i = 0; i < nr_redist_regions; i++) {
- struct resource res;
- int ret;
-
- ret = of_address_to_resource(node, 1 + i, &res);
- rdist_regs[i].redist_base = of_io_request_and_map(node, 1 + i, "GICR");
- if (ret || IS_ERR(rdist_regs[i].redist_base)) {
+ rdist_regs[i].redist_base = gic_of_iomap(node, 1 + i, "GICR", &res);
+ if (IS_ERR(rdist_regs[i].redist_base)) {
pr_err("%pOF: couldn't map region %d\n", node, i);
err = -ENODEV;
goto out_unmap_rdist;
@@ -2151,7 +2172,7 @@ gic_acpi_parse_madt_redist(union acpi_subtable_headers *header,
pr_err("Couldn't map GICR region @%llx\n", redist->base_address);
return -ENOMEM;
}
- request_mem_region(redist->base_address, redist->length, "GICR");
+ gic_request_region(redist->base_address, redist->length, "GICR");

gic_acpi_register_redist(redist->base_address, redist_base);
return 0;
@@ -2174,7 +2195,7 @@ gic_acpi_parse_madt_gicc(union acpi_subtable_headers *header,
redist_base = ioremap(gicc->gicr_base_address, size);
if (!redist_base)
return -ENOMEM;
- request_mem_region(gicc->gicr_base_address, size, "GICR");
+ gic_request_region(gicc->gicr_base_address, size, "GICR");

gic_acpi_register_redist(gicc->gicr_base_address, redist_base);
return 0;
@@ -2376,7 +2397,7 @@ gic_acpi_init(union acpi_subtable_headers *header, const unsigned long end)
pr_err("Unable to map GICD registers\n");
return -ENOMEM;
}
- request_mem_region(dist->base_address, ACPI_GICV3_DIST_MEM_SIZE, "GICD");
+ gic_request_region(dist->base_address, ACPI_GICV3_DIST_MEM_SIZE, "GICD");

err = gic_validate_dist_version(acpi_data.dist_base);
if (err) {