diff options
Diffstat (limited to 'arch/x86/realmode/rm')
| -rw-r--r-- | arch/x86/realmode/rm/Makefile | 11 | ||||
| -rw-r--r-- | arch/x86/realmode/rm/reboot.S | 3 | ||||
| -rw-r--r-- | arch/x86/realmode/rm/trampoline_64.S | 33 |
3 files changed, 34 insertions, 13 deletions
diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile index f614009d3e4e..a0fb39abc5c8 100644 --- a/arch/x86/realmode/rm/Makefile +++ b/arch/x86/realmode/rm/Makefile @@ -7,15 +7,6 @@ # # -# Sanitizer runtimes are unavailable and cannot be linked here. -KASAN_SANITIZE := n -KCSAN_SANITIZE := n -KMSAN_SANITIZE := n -OBJECT_FILES_NON_STANDARD := y - -# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. -KCOV_INSTRUMENT := n - always-y := realmode.bin realmode.relocs wakeup-objs := wakeup_asm.o wakemain.o video-mode.o @@ -76,5 +67,3 @@ KBUILD_CFLAGS := $(REALMODE_CFLAGS) -D_SETUP -D_WAKEUP \ -I$(srctree)/arch/x86/boot KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__ KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -GCOV_PROFILE := n -UBSAN_SANITIZE := n diff --git a/arch/x86/realmode/rm/reboot.S b/arch/x86/realmode/rm/reboot.S index f10515b10e0a..e714b4624e36 100644 --- a/arch/x86/realmode/rm/reboot.S +++ b/arch/x86/realmode/rm/reboot.S @@ -1,5 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ #include <linux/linkage.h> +#include <asm/desc_defs.h> #include <asm/segment.h> #include <asm/page_types.h> #include <asm/processor-flags.h> @@ -153,5 +154,5 @@ SYM_DATA_START(machine_real_restart_gdt) * base value 0x100; since this is consistent with real mode * semantics we don't have to reload the segments once CR0.PE = 0. */ - .quad GDT_ENTRY(0x0093, 0x100, 0xffff) + .quad GDT_ENTRY(DESC_DATA16, 0x100, 0xffff) SYM_DATA_END(machine_real_restart_gdt) diff --git a/arch/x86/realmode/rm/trampoline_64.S b/arch/x86/realmode/rm/trampoline_64.S index c9f76fae902e..14d9c7daf90f 100644 --- a/arch/x86/realmode/rm/trampoline_64.S +++ b/arch/x86/realmode/rm/trampoline_64.S @@ -37,13 +37,15 @@ .text .code16 -.macro LOCK_AND_LOAD_REALMODE_ESP lock_pa=0 +.macro LOCK_AND_LOAD_REALMODE_ESP lock_pa=0 lock_rip=0 /* * Make sure only one CPU fiddles with the realmode stack */ .Llock_rm\@: .if \lock_pa lock btsl $0, pa_tr_lock + .elseif \lock_rip + lock btsl $0, tr_lock(%rip) .else lock btsl $0, tr_lock .endif @@ -220,6 +222,35 @@ SYM_CODE_START(trampoline_start64) lidt tr_idt(%rip) lgdt tr_gdt64(%rip) + /* Check if paging mode has to be changed */ + movq %cr4, %rax + xorl tr_cr4(%rip), %eax + testl $X86_CR4_LA57, %eax + jnz .L_switch_paging + + /* Paging mode is correct proceed in 64-bit mode */ + + LOCK_AND_LOAD_REALMODE_ESP lock_rip=1 + + movw $__KERNEL_DS, %dx + movl %edx, %ss + addl $pa_real_mode_base, %esp + movl %edx, %ds + movl %edx, %es + movl %edx, %fs + movl %edx, %gs + + movl $pa_trampoline_pgd, %eax + movq %rax, %cr3 + + pushq $__KERNEL_CS + pushq tr_start(%rip) + lretq +.L_switch_paging: + /* + * To switch between 4- and 5-level paging modes, it is necessary + * to disable paging. This must be done in the compatibility mode. + */ ljmpl *tr_compat(%rip) SYM_CODE_END(trampoline_start64) |