[PATCH 1/1] media: intel/ipu6: Don't re-allocate memory for firmware

From: Sakari Ailus
Date: Thu May 02 2024 - 11:50:25 EST


The ipu6 driver allocated vmalloc memory for the firmware if
request_firmware() somehow managed not to use vmalloc to allocate it.

Still how the memory is allocated by request_firmware() is not specified
in its API, so be prepared for kmalloc-allocated firmware, too. Instead of
allocating new vmalloc-backed buffer for the firmware, obtain the pages
from virtual addresses instead.

Reported-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Fixes: 25fedc021985 ("media: intel/ipu6: add Intel IPU6 PCI device driver")
Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
---
Hello everyone,

Mauro preferred not to merge the earlier patch. Admittedly, there are
better ways to fix the problem. Such as this one.

- Sakari

drivers/media/pci/intel/ipu6/ipu6-buttress.c | 7 +++-
drivers/media/pci/intel/ipu6/ipu6.c | 41 +-------------------
2 files changed, 7 insertions(+), 41 deletions(-)

diff --git a/drivers/media/pci/intel/ipu6/ipu6-buttress.c b/drivers/media/pci/intel/ipu6/ipu6-buttress.c
index dbcf1aa87872..23c537e7ce1e 100644
--- a/drivers/media/pci/intel/ipu6/ipu6-buttress.c
+++ b/drivers/media/pci/intel/ipu6/ipu6-buttress.c
@@ -552,12 +552,16 @@ int ipu6_buttress_reset_authentication(struct ipu6_device *isp)
int ipu6_buttress_map_fw_image(struct ipu6_bus_device *sys,
const struct firmware *fw, struct sg_table *sgt)
{
+ bool is_vmalloc = is_vmalloc_addr(fw->data);
struct page **pages;
const void *addr;
unsigned long n_pages;
unsigned int i;
int ret;

+ if (!is_vmalloc && !virt_addr_valid(fw->data))
+ return -EDOM;
+
n_pages = PHYS_PFN(PAGE_ALIGN(fw->size));

pages = kmalloc_array(n_pages, sizeof(*pages), GFP_KERNEL);
@@ -566,7 +570,8 @@ int ipu6_buttress_map_fw_image(struct ipu6_bus_device *sys,

addr = fw->data;
for (i = 0; i < n_pages; i++) {
- struct page *p = vmalloc_to_page(addr);
+ struct page *p = is_vmalloc ?
+ vmalloc_to_page(addr) : virt_to_page(addr);

if (!p) {
ret = -ENOMEM;
diff --git a/drivers/media/pci/intel/ipu6/ipu6.c b/drivers/media/pci/intel/ipu6/ipu6.c
index 7bcd9c5a381a..2cf04251c9e7 100644
--- a/drivers/media/pci/intel/ipu6/ipu6.c
+++ b/drivers/media/pci/intel/ipu6/ipu6.c
@@ -503,45 +503,6 @@ static void ipu6_configure_vc_mechanism(struct ipu6_device *isp)
writel(val, isp->base + BUTTRESS_REG_BTRS_CTRL);
}

-static int request_cpd_fw(const struct firmware **firmware_p, const char *name,
- struct device *device)
-{
- const struct firmware *fw;
- struct firmware *dst;
- int ret = 0;
-
- ret = request_firmware(&fw, name, device);
- if (ret)
- return ret;
-
- if (is_vmalloc_addr(fw->data)) {
- *firmware_p = fw;
- return 0;
- }
-
- dst = kzalloc(sizeof(*dst), GFP_KERNEL);
- if (!dst) {
- ret = -ENOMEM;
- goto release_firmware;
- }
-
- dst->size = fw->size;
- dst->data = vmalloc(fw->size);
- if (!dst->data) {
- kfree(dst);
- ret = -ENOMEM;
- goto release_firmware;
- }
-
- memcpy((void *)dst->data, fw->data, fw->size);
- *firmware_p = dst;
-
-release_firmware:
- release_firmware(fw);
-
- return ret;
-}
-
static int ipu6_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
struct ipu6_buttress_ctrl *isys_ctrl = NULL, *psys_ctrl = NULL;
@@ -627,7 +588,7 @@ static int ipu6_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
if (ret)
return ret;

- ret = request_cpd_fw(&isp->cpd_fw, isp->cpd_fw_name, dev);
+ ret = request_firmware(&isp->cpd_fw, isp->cpd_fw_name, dev);
if (ret) {
dev_err_probe(&isp->pdev->dev, ret,
"Requesting signed firmware %s failed\n",
--
2.39.2