[PATCH 5.15 204/230] i2c: piix4: Fix a memory leak in the EFCH MMIO support

Greg Kroah-Hartman
2022-07-11T10:02:46Z

From: Jean Delvare <jdelvare@suse.de>

[ Upstream commit 8ad59b397f86a4d8014966fdc0552095a0c4fb2b ]

The recently added support for EFCH MMIO regions introduced a memory
leak in that code path. The leak is caused by the fact that
release_resource() merely removes the resource from the tree but does
not free its memory. We need to call release_mem_region() instead,
which does free the memory. As a nice side effect, this brings back
some symmetry between the legacy and MMIO paths.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Reviewed-by: Terry Bowman <terry.bowman@amd.com>
Tested-by: Terry Bowman <Terry.Bowman@amd.com>
Fixes: 7c148722d074 ("i2c: piix4: Add EFCH MMIO support to region request and release")
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/i2c/busses/i2c-piix4.c | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index ac8e7d60672a..39cb1b7bb865 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -161,7 +161,6 @@ static const char *piix4_aux_port_name_sb800 = " port 1";

struct sb800_mmio_cfg {
void __iomem *addr;
- struct resource *res;
bool use_mmio;
};

@@ -179,13 +178,11 @@ static int piix4_sb800_region_request(struct device *dev,
struct sb800_mmio_cfg *mmio_cfg)
{
if (mmio_cfg->use_mmio) {
- struct resource *res;
void __iomem *addr;

- res = request_mem_region_muxed(SB800_PIIX4_FCH_PM_ADDR,
- SB800_PIIX4_FCH_PM_SIZE,
- "sb800_piix4_smb");
- if (!res) {
+ if (!request_mem_region_muxed(SB800_PIIX4_FCH_PM_ADDR,
+ SB800_PIIX4_FCH_PM_SIZE,
+ "sb800_piix4_smb")) {
dev_err(dev,
"SMBus base address memory region 0x%x already in use.\n",
SB800_PIIX4_FCH_PM_ADDR);
@@ -195,12 +192,12 @@ static int piix4_sb800_region_request(struct device *dev,
addr = ioremap(SB800_PIIX4_FCH_PM_ADDR,
SB800_PIIX4_FCH_PM_SIZE);
if (!addr) {
- release_resource(res);
+ release_mem_region(SB800_PIIX4_FCH_PM_ADDR,
+ SB800_PIIX4_FCH_PM_SIZE);
dev_err(dev, "SMBus base address mapping failed.\n");
return -ENOMEM;
}

- mmio_cfg->res = res;
mmio_cfg->addr = addr;

return 0;
@@ -222,7 +219,8 @@ static void piix4_sb800_region_release(struct device *dev,
{
if (mmio_cfg->use_mmio) {
iounmap(mmio_cfg->addr);
- release_resource(mmio_cfg->res);
+ release_mem_region(SB800_PIIX4_FCH_PM_ADDR,
+ SB800_PIIX4_FCH_PM_SIZE);
return;
}

--
2.35.1