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

[Lakshmi Ramasubramanian]

On 2/10/21 5:42 PM, Thiago Jung Bauermann wrote:
> Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx> writes:
>
> > From: Rob Herring <robh@xxxxxxxxxx>
> >
> > 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@xxxxxxxxxx>
> > Signed-off-by: Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx>
> > ---
> >   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 <bauerman@xxxxxxxxxxxxx>
>
> And also:
>
> Tested-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx>

Thanks a lot for your help Thiago.

 -lakshmi