On Tue, 17 Dec 2024 at 00:37, David Woodhouse <dwmw2@xxxxxxxxxxxxx> wrote:
>
> From: David Woodhouse <dwmw@xxxxxxxxxxxx>
>
> Both i386 and x86_64 now copy the relocate_kernel function into the control
> page and execute it from there, using an open-coded function pointer.
>
> Use a typedef for it instead.
>
> Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
> ---
> arch/x86/include/asm/kexec.h | 26 +++++++++++++-------------
> arch/x86/kernel/machine_kexec_32.c | 7 +------
> arch/x86/kernel/machine_kexec_64.c | 6 +-----
> 3 files changed, 15 insertions(+), 24 deletions(-)
>
> diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
> index 48e4f44f794f..8ad187462b68 100644
> --- a/arch/x86/include/asm/kexec.h
> +++ b/arch/x86/include/asm/kexec.h
> @@ -111,21 +111,21 @@ static inline void crash_setup_regs(struct pt_regs *newregs,
> }
>
> #ifdef CONFIG_X86_32
> -asmlinkage unsigned long
> -relocate_kernel(unsigned long indirection_page,
> - unsigned long control_page,
> - unsigned long start_address,
> - unsigned int has_pae,
> - unsigned int preserve_context);
> +typedef asmlinkage unsigned long
> +relocate_kernel_fn(unsigned long indirection_page,
> + unsigned long control_page,
> + unsigned long start_address,
> + unsigned int has_pae,
> + unsigned int preserve_context);
linkage is not part of the type. 'asmlinkage' is #define'd to the
empty string today, so it doesn't matter, but better to omit it here.
> #else
> -unsigned long
> -relocate_kernel(unsigned long indirection_page,
> - unsigned long pa_control_page,
> - unsigned long start_address,
> - unsigned int preserve_context,
> - unsigned int host_mem_enc_active);
> +typedef unsigned long
> +relocate_kernel_fn(unsigned long indirection_page,
> + unsigned long pa_control_page,
> + unsigned long start_address,
> + unsigned int preserve_context,
> + unsigned int host_mem_enc_active);
> #endif
> -
> +extern relocate_kernel_fn relocate_kernel;
> #define ARCH_HAS_KIMAGE_ARCH
>
> #ifdef CONFIG_X86_32
> diff --git a/arch/x86/kernel/machine_kexec_32.c b/arch/x86/kernel/machine_kexec_32.c
> index 1b373d79cedc..80265162aeff 100644
> --- a/arch/x86/kernel/machine_kexec_32.c
> +++ b/arch/x86/kernel/machine_kexec_32.c
> @@ -160,15 +160,10 @@ void machine_kexec_cleanup(struct kimage *image)
> */
> void machine_kexec(struct kimage *image)
> {
> + relocate_kernel_fn *relocate_kernel_ptr;
> unsigned long page_list[PAGES_NR];
> void *control_page;
> int save_ftrace_enabled;
> - asmlinkage unsigned long
> - (*relocate_kernel_ptr)(unsigned long indirection_page,
> - unsigned long control_page,
> - unsigned long start_address,
> - unsigned int has_pae,
> - unsigned int preserve_context);
>
> #ifdef CONFIG_KEXEC_JUMP
> if (image->preserve_context)
> diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
> index 1440f792a86d..dd75a51463a2 100644
> --- a/arch/x86/kernel/machine_kexec_64.c
> +++ b/arch/x86/kernel/machine_kexec_64.c
> @@ -344,12 +344,8 @@ void machine_kexec_cleanup(struct kimage *image)
> */
> void __nocfi machine_kexec(struct kimage *image)
> {
> - unsigned long (*relocate_kernel_ptr)(unsigned long indirection_page,
> - unsigned long pa_control_page,
> - unsigned long start_address,
> - unsigned int preserve_context,
> - unsigned int host_mem_enc_active);
> unsigned long reloc_start = (unsigned long)__relocate_kernel_start;
> + relocate_kernel_fn *relocate_kernel_ptr;
> unsigned int host_mem_enc_active;
> int save_ftrace_enabled;
> void *control_page;
> --
> 2.47.0
>
