[PATCH v3 6/7] x86/kexec: Pass boot params directly to new kernel

[Kevin Lampis <kevin.lampis@xxxxxxxxxx>]

When doing kexec on an EFI image there is no purgatory and kexec_reloc.S
hands off straight to the new kernel. To facilitate this the Linux
kernel boot params need to be passed through %rsi.

Signed-off-by: Kevin Lampis <kevin.lampis@xxxxxxxxxx>
---
Changes in v2:
- Rename kexec_image->boot_params to entry_arg
- Fix indentation
---
 xen/arch/x86/include/asm/machine_kexec.h | 2 +-
 xen/arch/x86/machine_kexec.c             | 3 ++-
 xen/arch/x86/x86_64/kexec_reloc.S        | 3 +++
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/xen/arch/x86/include/asm/machine_kexec.h 
b/xen/arch/x86/include/asm/machine_kexec.h
index 3e189acf2464..010e0c704626 100644
--- a/xen/arch/x86/include/asm/machine_kexec.h
+++ b/xen/arch/x86/include/asm/machine_kexec.h
@@ -7,7 +7,7 @@
 
 extern void kexec_reloc(unsigned long reloc_code, unsigned long reloc_pt,
                         unsigned long ind_maddr, unsigned long entry_maddr,
-                        unsigned long flags);
+                        unsigned long flags, unsigned long arg);
 
 extern const char kexec_reloc_end[];
 
diff --git a/xen/arch/x86/machine_kexec.c b/xen/arch/x86/machine_kexec.c
index 038670922d47..67ca3e09bece 100644
--- a/xen/arch/x86/machine_kexec.c
+++ b/xen/arch/x86/machine_kexec.c
@@ -199,7 +199,8 @@ void machine_kexec(struct kexec_image *image)
 
     kexec_reloc(page_to_maddr(image->control_code_page),
                 page_to_maddr(image->aux_page),
-                image->head, image->entry_maddr, reloc_flags);
+                image->head, image->entry_maddr, reloc_flags,
+                image->entry_arg);
 }
 
 int machine_kexec_get(xen_kexec_range_t *range)
diff --git a/xen/arch/x86/x86_64/kexec_reloc.S 
b/xen/arch/x86/x86_64/kexec_reloc.S
index 1d023733a916..0f163862b858 100644
--- a/xen/arch/x86/x86_64/kexec_reloc.S
+++ b/xen/arch/x86/x86_64/kexec_reloc.S
@@ -41,6 +41,7 @@ FUNC(kexec_reloc, PAGE_SIZE)
         /* %rdx - indirection page maddr */
         /* %rcx - entry maddr (%rbp) */
         /* %r8 - flags */
+        /* %r9 - entry arg */
 
         movq    %rcx, %rbp
 
@@ -104,6 +105,8 @@ FUNC(kexec_reloc, PAGE_SIZE)
         movq    %rdx, %rdi
         call    relocate_pages
 
+        movq    %r9, %rsi /* entry arg */
+
         /* Need to switch to 32-bit mode? */
         testq   $KEXEC_RELOC_FLAG_COMPAT, %r8
         jnz     .L_call_32_bit
-- 
2.52.0