[v6,5/7] x86/kexec: convert entry point annotations

Commit Message

Jan Beulich Feb. 7, 2024, 1:38 p.m. UTC

Use the generic framework from xen/linkage.h.

Signed-off-by: Jan Beulich <[e-mail]>
---
Using the linker script like this feels fragile. Maybe it's better to
suppress (#undef) CONFIG_CC_SPLIT_SECTIONS for this one file?
---
v6: New.

Comments

Andrew Cooper Feb. 7, 2024, 2:05 p.m. UTC | #1

On 07/02/2024 1:38 pm, Jan Beulich wrote:
> Use the generic framework from xen/linkage.h.
>
> Signed-off-by: Jan Beulich <[e-mail]>
> ---
> Using the linker script like this feels fragile. Maybe it's better to
> suppress (#undef) CONFIG_CC_SPLIT_SECTIONS for this one file?

This is specific glue code, needing to fit in a single page.  I'd prefer
to explicitly state that SPLIT_SECTIONS is inapplciable, than to try to
undo the effects in the linker script.

Everything else looks ok.  I'll fix the preexiting errors after a rebase.

~Andrew

Patch

--- a/xen/arch/x86/x86_64/kexec_reloc.S
+++ b/xen/arch/x86/x86_64/kexec_reloc.S
@@ -21,10 +21,9 @@ 
 #include <asm/machine_kexec.h>
 
         .section .text.kexec, "ax", @progbits
-        .align PAGE_SIZE
         .code64
 
-ENTRY(kexec_reloc)
+FUNC(kexec_reloc, PAGE_SIZE)
         /* %rdi - code page maddr */
         /* %rsi - page table maddr */
         /* %rdx - indirection page maddr */
@@ -91,8 +90,9 @@  ENTRY(kexec_reloc)
         push    $0x10
         push    %rax
         lretq
+END(kexec_reloc)
 
-relocate_pages:
+FUNC_LOCAL(relocate_pages)
         /* %rdi - indirection page maddr */
         pushq   %rbx
 
@@ -138,10 +138,11 @@  relocate_pages:
 .L_done:
         popq    %rbx
         ret
+END(relocate_pages)
 
         .code32
 
-compatibility_mode:
+FUNC_LOCAL(compatibility_mode)
         /* Setup some sane segments. */
         movl    $0x0008, %eax
         movl    %eax, %ds
@@ -168,39 +169,29 @@  compatibility_mode:
         /* Call the image entry point.  This should never return. */
         call    *%ebp
         ud2
+END(compatibility_mode)
 
-        .align 4
-compat_mode_gdt_desc:
+DATA_LOCAL(compat_mode_gdt_desc, 4)
         .word .Lcompat_mode_gdt_end - compat_mode_gdt -1
         .quad 0x0000000000000000     /* set in call_32_bit above */
+END(compat_mode_gdt_desc)
 
-        .type compat_mode_gdt_desc, @object
-        .size compat_mode_gdt_desc, . - compat_mode_gdt_desc
-
-        .align 8
-compat_mode_gdt:
+DATA_LOCAL(compat_mode_gdt, 8)
         .quad 0x0000000000000000     /* null                              */
         .quad 0x00cf93000000ffff     /* 0x0008 ring 0 data                */
         .quad 0x00cf9b000000ffff     /* 0x0010 ring 0 code, compatibility */
 .Lcompat_mode_gdt_end:
+END(compat_mode_gdt)
 
-        .type compat_mode_gdt, @object
-        .size compat_mode_gdt, . - compat_mode_gdt
-
-compat_mode_idt:
+DATA_LOCAL(compat_mode_idt)
         .word 0                      /* limit */
         .long 0                      /* base */
-
-        .type compat_mode_idt, @object
-        .size compat_mode_idt, . - compat_mode_idt
+END(compat_mode_idt)
 
         /*
          * 16 words of stack are more than enough.
          */
-        .align 8
-reloc_stack:
+DATA_LOCAL(reloc_stack, 8)
         .fill 16,8,0
 .Lreloc_stack_base:
-
-        .type reloc_stack, @object
-        .size reloc_stack, . - reloc_stack
+END(reloc_stack)
--- a/xen/arch/x86/xen.lds.S
+++ b/xen/arch/x86/xen.lds.S
@@ -92,7 +92,10 @@  SECTIONS
        . = ALIGN(PAGE_SIZE);
        _etextentry = .;
 
-       *(.text.kexec)          /* Page aligned in the object file. */
+       /* Page aligned in the object file. */
+       *(.text.kexec.kexec_reloc)
+       *(.text.kexec.*)
+       *(.text.kexec)
        kexec_reloc_end = .;
 
        *(.text.cold)