lkml.org 
[lkml]   [2021]   [Feb]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] powerpc/kexec_file: Restore FDT size estimation for kdump kernel
From
Date
On 2/19/21 6:25 AM, Thiago Jung Bauermann wrote:

One small nit in the function header (please see below), but otherwise
the change looks good.

Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>

> Commit 2377c92e37fe ("powerpc/kexec_file: fix FDT size estimation for kdump
> kernel") fixed how elf64_load() estimates the FDT size needed by the
> crashdump kernel.
>
> At the same time, commit 130b2d59cec0 ("powerpc: Use common
> of_kexec_alloc_and_setup_fdt()") changed the same code to use the generic
> function of_kexec_alloc_and_setup_fdt() to calculate the FDT size. That
> change made the code overestimate it a bit by counting twice the space
> required for the kernel command line and /chosen properties.
>
> Therefore change kexec_fdt_totalsize_ppc64() to calculate just the extra
> space needed by the kdump kernel, and change the function name so that it
> better reflects what the function is now doing.
>
> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
> ---
> arch/powerpc/include/asm/kexec.h | 2 +-
> arch/powerpc/kexec/elf_64.c | 2 +-
> arch/powerpc/kexec/file_load_64.c | 26 ++++++++------------------
> 3 files changed, 10 insertions(+), 20 deletions(-)
>
> Applies on top of next-20210219.
>
> diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
> index baab158e215c..5a11cc8d2350 100644
> --- a/arch/powerpc/include/asm/kexec.h
> +++ b/arch/powerpc/include/asm/kexec.h
> @@ -128,7 +128,7 @@ int load_crashdump_segments_ppc64(struct kimage *image,
> int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
> const void *fdt, unsigned long kernel_load_addr,
> unsigned long fdt_load_addr);
> -unsigned int kexec_fdt_totalsize_ppc64(struct kimage *image);
> +unsigned int kexec_extra_fdt_size_ppc64(struct kimage *image);
> int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
> unsigned long initrd_load_addr,
> unsigned long initrd_len, const char *cmdline);
> diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
> index 0492ca6003f3..5a569bb51349 100644
> --- a/arch/powerpc/kexec/elf_64.c
> +++ b/arch/powerpc/kexec/elf_64.c
> @@ -104,7 +104,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
>
> fdt = of_kexec_alloc_and_setup_fdt(image, initrd_load_addr,
> initrd_len, cmdline,
> - kexec_fdt_totalsize_ppc64(image));
> + kexec_extra_fdt_size_ppc64(image));
> if (!fdt) {
> pr_err("Error setting up the new device tree.\n");
> ret = -EINVAL;
> diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
> index 3609de30a170..8541ba731908 100644
> --- a/arch/powerpc/kexec/file_load_64.c
> +++ b/arch/powerpc/kexec/file_load_64.c
> @@ -927,37 +927,27 @@ int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
> }
>
> /**
> - * kexec_fdt_totalsize_ppc64 - Return the estimated size needed to setup FDT
> - * for kexec/kdump kernel.
> - * @image: kexec image being loaded.
> + * kexec_extra_fdt_size_ppc63 - Return the estimated size needed to setup FDT

Perhaps change to

"Return the estimated additional size needed to setup FDT for
kexec/kdump kernel"?

-lakshmi

> + * for kexec/kdump kernel.
> + * @image: kexec image being loaded.
> *
> - * Returns the estimated size needed for kexec/kdump kernel FDT.
> + * Returns the estimated extra size needed for kexec/kdump kernel FDT.
> */
> -unsigned int kexec_fdt_totalsize_ppc64(struct kimage *image)
> +unsigned int kexec_extra_fdt_size_ppc64(struct kimage *image)
> {
> - unsigned int fdt_size;
> u64 usm_entries;
>
> - /*
> - * The below estimate more than accounts for a typical kexec case where
> - * the additional space is to accommodate things like kexec cmdline,
> - * chosen node with properties for initrd start & end addresses and
> - * a property to indicate kexec boot..
> - */
> - fdt_size = fdt_totalsize(initial_boot_params) + (2 * COMMAND_LINE_SIZE);
> if (image->type != KEXEC_TYPE_CRASH)
> - return fdt_size;
> + return 0;
>
> /*
> - * For kdump kernel, also account for linux,usable-memory and
> + * For kdump kernel, account for linux,usable-memory and
> * linux,drconf-usable-memory properties. Get an approximate on the
> * number of usable memory entries and use for FDT size estimation.
> */
> usm_entries = ((memblock_end_of_DRAM() / drmem_lmb_size()) +
> (2 * (resource_size(&crashk_res) / drmem_lmb_size())));
> - fdt_size += (unsigned int)(usm_entries * sizeof(u64));
> -
> - return fdt_size;
> + return (unsigned int)(usm_entries * sizeof(u64));
> }
>
> /**
>

\
 
 \ /
  Last update: 2021-02-19 17:02    [W:0.620 / U:0.976 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site