Re: [PATCH v17 04/10] powerpc: Use common of_kexec_alloc_and_setup_fdt()

Thiago Jung Bauermann
2021-02-11T01:44:26Z

Lakshmi Ramasubramanian <nramas@linux.microsoft.com> writes:

> 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 <nramas@linux.microsoft.com>
> ---
> 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:

Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>

And also:

Tested-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>

--
Thiago Jung Bauermann
IBM Linux Technology Center