diff options
Diffstat (limited to 'arch/x86/xen/xen-pvh.S')
| -rw-r--r-- | arch/x86/xen/xen-pvh.S | 64 |
1 files changed, 40 insertions, 24 deletions
diff --git a/arch/x86/xen/xen-pvh.S b/arch/x86/xen/xen-pvh.S index e1a5fbeae08d..1f8825bbaffb 100644 --- a/arch/x86/xen/xen-pvh.S +++ b/arch/x86/xen/xen-pvh.S @@ -1,18 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + /* * Copyright C 2016, Oracle and/or its affiliates. All rights reserved. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License along - * with this program. If not, see <http://www.gnu.org/licenses/>. */ .code32 @@ -54,12 +43,19 @@ * charge of setting up it's own stack, GDT and IDT. */ +#define PVH_GDT_ENTRY_CS 1 +#define PVH_GDT_ENTRY_DS 2 +#define PVH_GDT_ENTRY_CANARY 3 +#define PVH_CS_SEL (PVH_GDT_ENTRY_CS * 8) +#define PVH_DS_SEL (PVH_GDT_ENTRY_DS * 8) +#define PVH_CANARY_SEL (PVH_GDT_ENTRY_CANARY * 8) + ENTRY(pvh_start_xen) cld lgdt (_pa(gdt)) - mov $(__BOOT_DS),%eax + mov $PVH_DS_SEL,%eax mov %eax,%ds mov %eax,%es mov %eax,%ss @@ -93,11 +89,17 @@ ENTRY(pvh_start_xen) mov %eax, %cr0 /* Jump to 64-bit mode. */ - ljmp $__KERNEL_CS, $_pa(1f) + ljmp $PVH_CS_SEL, $_pa(1f) /* 64-bit entry point. */ .code64 1: + /* Set base address in stack canary descriptor. */ + mov $MSR_GS_BASE,%ecx + mov $_pa(canary), %eax + xor %edx, %edx + wrmsr + call xen_prepare_pvh /* startup_64 expects boot_params in %rsi. */ @@ -107,6 +109,17 @@ ENTRY(pvh_start_xen) #else /* CONFIG_X86_64 */ + /* Set base address in stack canary descriptor. */ + movl $_pa(gdt_start),%eax + movl $_pa(canary),%ecx + movw %cx, (PVH_GDT_ENTRY_CANARY * 8) + 2(%eax) + shrl $16, %ecx + movb %cl, (PVH_GDT_ENTRY_CANARY * 8) + 4(%eax) + movb %ch, (PVH_GDT_ENTRY_CANARY * 8) + 7(%eax) + + mov $PVH_CANARY_SEL,%eax + mov %eax,%gs + call mk_early_pgtbl_32 mov $_pa(initial_page_table), %eax @@ -116,13 +129,13 @@ ENTRY(pvh_start_xen) or $(X86_CR0_PG | X86_CR0_PE), %eax mov %eax, %cr0 - ljmp $__BOOT_CS, $1f + ljmp $PVH_CS_SEL, $1f 1: call xen_prepare_pvh mov $_pa(pvh_bootparams), %esi /* startup_32 doesn't expect paging and PAE to be on. */ - ljmp $__BOOT_CS, $_pa(2f) + ljmp $PVH_CS_SEL, $_pa(2f) 2: mov %cr0, %eax and $~X86_CR0_PG, %eax @@ -131,7 +144,7 @@ ENTRY(pvh_start_xen) and $~X86_CR4_PAE, %eax mov %eax, %cr4 - ljmp $__BOOT_CS, $_pa(startup_32) + ljmp $PVH_CS_SEL, $_pa(startup_32) #endif END(pvh_start_xen) @@ -143,18 +156,21 @@ gdt: .word 0 gdt_start: .quad 0x0000000000000000 /* NULL descriptor */ - .quad 0x0000000000000000 /* reserved */ #ifdef CONFIG_X86_64 - .quad GDT_ENTRY(0xa09a, 0, 0xfffff) /* __KERNEL_CS */ + .quad GDT_ENTRY(0xa09a, 0, 0xfffff) /* PVH_CS_SEL */ #else - .quad GDT_ENTRY(0xc09a, 0, 0xfffff) /* __KERNEL_CS */ + .quad GDT_ENTRY(0xc09a, 0, 0xfffff) /* PVH_CS_SEL */ #endif - .quad GDT_ENTRY(0xc092, 0, 0xfffff) /* __KERNEL_DS */ + .quad GDT_ENTRY(0xc092, 0, 0xfffff) /* PVH_DS_SEL */ + .quad GDT_ENTRY(0x4090, 0, 0x18) /* PVH_CANARY_SEL */ gdt_end: - .balign 4 + .balign 16 +canary: + .fill 48, 1, 0 + early_stack: - .fill 256, 1, 0 + .fill BOOT_STACK_SIZE, 1, 0 early_stack_end: ELFNOTE(Xen, XEN_ELFNOTE_PHYS32_ENTRY, |