Commit 7c61a3d8 authored by David Woodhouse's avatar David Woodhouse Committed by Borislav Petkov (AMD)
Browse files

x86/kexec: Use typedef for relocate_kernel_fn function prototype 



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.

  [ bp: Put relocate_kernel_ptr ptr arithmetic on a single line. ]

Signed-off-by: default avatarDavid Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20250109140757.2841269-10-dwmw2@infradead.org
parent e5360575

arch/x86/include/asm/kexec.h

+13 −13
Original line number Diff line number Diff line
@@ -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,

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);

#else

unsigned long

relocate_kernel(unsigned long indirection_page,

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

arch/x86/kernel/machine_kexec_32.c

+1 −6
Original line number Diff line number Diff line
@@ -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)

arch/x86/kernel/machine_kexec_64.c

+2 −7
Original line number Diff line number Diff line
@@ -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;
@@ -391,8 +387,7 @@ void __nocfi machine_kexec(struct kimage *image) 
	 * Allow for the possibility that relocate_kernel might not be at

	 * the very start of the page.

	 */

	relocate_kernel_ptr = control_page + (unsigned long)relocate_kernel -

		reloc_start;

	relocate_kernel_ptr = control_page + (unsigned long)relocate_kernel - reloc_start;



	/*

	 * The segment registers are funny things, they have both a