[PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer

From: Lakshmi Ramasubramanian
Date: Fri Jan 15 2021 - 12:32:29 EST


create_dtb() function allocates kernel virtual memory for
the device tree blob (DTB). This is not consistent with other
architectures, such as powerpc, which calls kmalloc() for allocating
memory for the DTB.

Call kmalloc() to allocate memory for the DTB, and kfree() to free
the allocated memory.

Co-developed-by: Prakhar Srivastava <prsriva@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Prakhar Srivastava <prsriva@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx>
---
arch/arm64/kernel/machine_kexec_file.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index 7de9c47dee7c..51c40143d6fa 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {

int arch_kimage_file_post_load_cleanup(struct kimage *image)
{
- vfree(image->arch.dtb);
+ kfree(image->arch.dtb);
image->arch.dtb = NULL;

vfree(image->arch.elf_headers);
@@ -59,19 +59,21 @@ static int create_dtb(struct kimage *image,
+ cmdline_len + DTB_EXTRA_SPACE;

for (;;) {
- buf = vmalloc(buf_size);
+ buf = kmalloc(buf_size, GFP_KERNEL);
if (!buf)
return -ENOMEM;

/* duplicate a device tree blob */
ret = fdt_open_into(initial_boot_params, buf, buf_size);
- if (ret)
+ if (ret) {
+ kfree(buf);
return -EINVAL;
+ }

ret = of_kexec_setup_new_fdt(image, buf, initrd_load_addr,
initrd_len, cmdline);
if (ret) {
- vfree(buf);
+ kfree(buf);
if (ret == -ENOMEM) {
/* unlikely, but just in case */
buf_size += DTB_EXTRA_SPACE;
@@ -217,6 +219,6 @@ int load_other_segments(struct kimage *image,
return 0;

out_err:
- vfree(dtb);
+ kfree(dtb);
return ret;
}
--
2.30.0