From: Ard Biesheuvel <ardb@xxxxxxxxxx> The purgatory is almost entirely position independent, without any need for any relocation processing at load time except for the reference to the GDT in the entry code. Generate this reference at runtime instead, to remove the last R_X86_64_64 relocation from this code. While the GDT itself needs to be preserved in memory as long as it is live, the GDT descriptor that is used to program the GDT can be discarded so it can be allocated on the stack. Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> --- arch/x86/purgatory/entry64.S | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/x86/purgatory/entry64.S b/arch/x86/purgatory/entry64.S index 9913877b0dbe..888661d9db9c 100644 --- a/arch/x86/purgatory/entry64.S +++ b/arch/x86/purgatory/entry64.S @@ -16,7 +16,11 @@ SYM_CODE_START(entry64) /* Setup a gdt that should be preserved */ - lgdt gdt(%rip) + leaq gdt(%rip), %rax + pushq %rax + pushw $gdt_end - gdt - 1 + lgdt (%rsp) + addq $10, %rsp /* load the data segments */ movl $0x18, %eax /* data segment */ @@ -83,8 +87,8 @@ SYM_DATA_START_LOCAL(gdt) * 0x08 unused * so use them as gdt ptr */ - .word gdt_end - gdt - 1 - .quad gdt + .word 0 + .quad 0 .word 0, 0, 0 /* 0x10 4GB flat code segment */ -- 2.44.0.769.g3c40516874-goog _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
