On 2/10/21 5:42 PM, Thiago Jung Bauermann wrote:

Lakshmi Ramasubramanian [off-list ref] writes:

quoted

From: Rob Herring <robh@kernel.org>

The code for setting up the /chosen node in the device tree
and updating the memory reservation for the next kernel has been
moved to of_kexec_alloc_and_setup_fdt() defined in "drivers/of/kexec.c".

Use the common of_kexec_alloc_and_setup_fdt() to setup the device tree
and update the memory reservation for kexec for powerpc.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lakshmi Ramasubramanian <redacted>
---
  arch/powerpc/include/asm/kexec.h  |   1 +
  arch/powerpc/kexec/elf_64.c       |  29 ++++---
  arch/powerpc/kexec/file_load.c    | 132 +-----------------------------
  arch/powerpc/kexec/file_load_64.c |   3 +
  4 files changed, 25 insertions(+), 140 deletions(-)

diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index dbf09d2f36d0..bdd0ddb9ac4d 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h

@@ -111,6 +111,7 @@ struct kimage_arch {
  	unsigned long elf_headers_mem;
  	unsigned long elf_headers_sz;
  	void *elf_headers;
+	void *fdt;
  
  #ifdef CONFIG_IMA_KEXEC
  	phys_addr_t ima_buffer_addr;

diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
index d0e459bb2f05..bfabd06f99b1 100644
--- a/arch/powerpc/kexec/elf_64.c
+++ b/arch/powerpc/kexec/elf_64.c

@@ -19,6 +19,7 @@
  #include <linux/kexec.h>
  #include <linux/libfdt.h>
  #include <linux/module.h>
+#include <linux/of.h>
  #include <linux/of_fdt.h>
  #include <linux/slab.h>
  #include <linux/types.h>

@@ -29,7 +30,6 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
  			unsigned long cmdline_len)
  {
  	int ret;
-	unsigned int fdt_size;
  	unsigned long kernel_load_addr;
  	unsigned long initrd_load_addr = 0, fdt_load_addr;
  	void *fdt;

@@ -102,19 +102,13 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
  		pr_debug("Loaded initrd at 0x%lx\n", initrd_load_addr);
  	}
  
-	fdt_size = fdt_totalsize(initial_boot_params) * 2;
-	fdt = kmalloc(fdt_size, GFP_KERNEL);
+	fdt = of_kexec_alloc_and_setup_fdt(image, initrd_load_addr,
+					   initrd_len, cmdline);
  	if (!fdt) {
  		pr_err("Not enough memory for the device tree.\n");

This error string can be a bit misleading now, since
of_kexec_alloc_and_setup_fdt() can fail for reasons other than lack of
memory. I suggest changing it to the error string from fdt_open_into()
below:

		pr_err("Error setting up the new device tree.\n");

With this change:

Agreed - I will make this change.

Reviewed-by: Thiago Jung Bauermann <redacted>

And also:

Tested-by: Thiago Jung Bauermann <redacted>

Thanks a lot for your help Thiago.

  -lakshmi