Hi, Youling,
On Mon, Aug 11, 2025 at 5:28 PM Youling Tang <youling.t...@linux.dev> wrote:
>
> From: Youling Tang <tangyoul...@kylinos.cn>
>
> Add inird loading support and pass it to the second kernel via the
> cmdline 'initrd=start,size'.
I think Patch-3 and Patch-5 should be merged into Patch-2.
Huacai
>
> Signed-off-by: Youling Tang <tangyoul...@kylinos.cn>
> ---
> arch/loongarch/kernel/machine_kexec_file.c | 71 ++++++++++++++++++++++
> 1 file changed, 71 insertions(+)
>
> diff --git a/arch/loongarch/kernel/machine_kexec_file.c
> b/arch/loongarch/kernel/machine_kexec_file.c
> index bc91ae0afa4c..e1240644f529 100644
> --- a/arch/loongarch/kernel/machine_kexec_file.c
> +++ b/arch/loongarch/kernel/machine_kexec_file.c
> @@ -34,13 +34,84 @@ int arch_kimage_file_post_load_cleanup(struct kimage
> *image)
> return kexec_image_post_load_cleanup_default(image);
> }
>
> +/* Adds the "initrd=start,size" command line parameter to command line. */
> +static void cmdline_add_initrd(struct kimage *image, unsigned long
> *cmdline_tmplen,
> + char *modified_cmdline, unsigned long initrd)
> +{
> + int initrd_strlen;
> +
> + initrd_strlen = sprintf(modified_cmdline + (*cmdline_tmplen),
> "initrd=0x%lx,0x%lx ",
> + initrd, image->initrd_buf_len);
> + *cmdline_tmplen += initrd_strlen;
> +}
> +
> +/*
> + * Tries to add the initrd to the image. If it is not possible to find
> + * valid locations, this function will undo changes to the image and return
> non
> + * zero.
> + */
> int load_other_segments(struct kimage *image,
> unsigned long kernel_load_addr,
> unsigned long kernel_size,
> char *initrd, unsigned long initrd_len,
> char *cmdline, unsigned long cmdline_len)
> {
> + struct kexec_buf kbuf;
> + unsigned long orig_segments = image->nr_segments;
> + char *modified_cmdline = NULL;
> + unsigned long cmdline_tmplen = 0;
> + unsigned long initrd_load_addr = 0;
> + int ret = 0;
> +
> +
> + kbuf.image = image;
> + /* not allocate anything below the kernel */
> + kbuf.buf_min = kernel_load_addr + kernel_size;
> +
> + modified_cmdline = kzalloc(COMMAND_LINE_SIZE, GFP_KERNEL);
> + if (!modified_cmdline)
> + return -EINVAL;
> +
> + /* Ensure it's nul terminated */
> + modified_cmdline[COMMAND_LINE_SIZE - 1] = '\0';
> +
> + /* load initrd */
> + if (initrd) {
> + kbuf.buffer = initrd;
> + kbuf.bufsz = initrd_len;
> + kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
> + kbuf.memsz = initrd_len;
> + kbuf.buf_align = 0;
> + /* within 1GB-aligned window of up to 32GB in size */
> + kbuf.buf_max = round_down(kernel_load_addr, SZ_1G)
> + + (unsigned long)SZ_1G * 32;
> + kbuf.top_down = false;
> +
> + ret = kexec_add_buffer(&kbuf);
> + if (ret)
> + goto out_err;
> + initrd_load_addr = kbuf.mem;
> +
> + kexec_dprintk("Loaded initrd at 0x%lx bufsz=0x%lx
> memsz=0x%lx\n",
> + initrd_load_addr, kbuf.bufsz, kbuf.memsz);
> +
> + /* Add the initrd=start,size parameter to the command line */
> + cmdline_add_initrd(image, &cmdline_tmplen, modified_cmdline,
> initrd_load_addr);
> + }
> +
> + if (cmdline_len + cmdline_tmplen > COMMAND_LINE_SIZE) {
> + pr_err("Appending kdump cmdline exceeds cmdline size\n");
> + ret = -EINVAL;
> + goto out_err;
> + }
> + memcpy(modified_cmdline + cmdline_tmplen, cmdline, cmdline_len);
> + cmdline = modified_cmdline;
> image->arch.cmdline_ptr = (unsigned long)cmdline;
>
> return 0;
> +
> +out_err:
> + image->nr_segments = orig_segments;
> + kfree(modified_cmdline);
> + return ret;
> }
> --
> 2.34.1
>
