diff options
author | Ingo Molnar <mingo@kernel.org> | 2024-02-14 12:45:07 +0300 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2024-02-14 12:45:07 +0300 |
commit | 03c11eb3b16dc0058589751dfd91f254be2be613 (patch) | |
tree | e5f2889212fec0bb0babdce9abd781ab487e246a /arch/x86/kernel/head_64.S | |
parent | de8c6a352131f642b82474abe0cbb5dd26a7e081 (diff) | |
parent | 841c35169323cd833294798e58b9bf63fa4fa1de (diff) | |
download | linux-03c11eb3b16dc0058589751dfd91f254be2be613.tar.xz |
Merge tag 'v6.8-rc4' into x86/percpu, to resolve conflicts and refresh the branch
Conflicts:
arch/x86/include/asm/percpu.h
arch/x86/include/asm/text-patching.h
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/head_64.S')
-rw-r--r-- | arch/x86/kernel/head_64.S | 60 |
1 files changed, 44 insertions, 16 deletions
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index bfe5ec2f4f83..bb8ee1ce6968 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -9,7 +9,7 @@ * Copyright (C) 2005 Eric Biederman <ebiederm@xmission.com> */ - +#include <linux/export.h> #include <linux/linkage.h> #include <linux/threads.h> #include <linux/init.h> @@ -22,7 +22,6 @@ #include <asm/percpu.h> #include <asm/nops.h> #include "../entry/calling.h" -#include <asm/export.h> #include <asm/nospec-branch.h> #include <asm/apicdef.h> #include <asm/fixmap.h> @@ -115,6 +114,28 @@ SYM_CODE_START_NOALIGN(startup_64) /* Form the CR3 value being sure to include the CR3 modifier */ addq $(early_top_pgt - __START_KERNEL_map), %rax + +#ifdef CONFIG_AMD_MEM_ENCRYPT + mov %rax, %rdi + mov %rax, %r14 + + addq phys_base(%rip), %rdi + + /* + * For SEV guests: Verify that the C-bit is correct. A malicious + * hypervisor could lie about the C-bit position to perform a ROP + * attack on the guest by writing to the unencrypted stack and wait for + * the next RET instruction. + */ + call sev_verify_cbit + + /* + * Restore CR3 value without the phys_base which will be added + * below, before writing %cr3. + */ + mov %r14, %rax +#endif + jmp 1f SYM_CODE_END(startup_64) @@ -180,10 +201,10 @@ SYM_INNER_LABEL(secondary_startup_64_no_verify, SYM_L_GLOBAL) movl $0, %ecx #endif - /* Enable PAE mode, PGE and LA57 */ - orl $(X86_CR4_PAE | X86_CR4_PGE), %ecx + /* Enable PAE mode, PSE, PGE and LA57 */ + orl $(X86_CR4_PAE | X86_CR4_PSE | X86_CR4_PGE), %ecx #ifdef CONFIG_X86_5LEVEL - testl $1, __pgtable_l5_enabled(%rip) + testb $1, __pgtable_l5_enabled(%rip) jz 1f orl $X86_CR4_LA57, %ecx 1: @@ -194,21 +215,12 @@ SYM_INNER_LABEL(secondary_startup_64_no_verify, SYM_L_GLOBAL) addq phys_base(%rip), %rax /* - * For SEV guests: Verify that the C-bit is correct. A malicious - * hypervisor could lie about the C-bit position to perform a ROP - * attack on the guest by writing to the unencrypted stack and wait for - * the next RET instruction. - */ - movq %rax, %rdi - call sev_verify_cbit - - /* * Switch to new page-table * * For the boot CPU this switches to early_top_pgt which still has the - * indentity mappings present. The secondary CPUs will switch to the + * identity mappings present. The secondary CPUs will switch to the * init_top_pgt here, away from the trampoline_pgd and unmap the - * indentity mapped ranges. + * identity mapped ranges. */ movq %rax, %cr3 @@ -256,6 +268,22 @@ SYM_INNER_LABEL(secondary_startup_64_no_verify, SYM_L_GLOBAL) testl $X2APIC_ENABLE, %eax jnz .Lread_apicid_msr +#ifdef CONFIG_X86_X2APIC + /* + * If system is in X2APIC mode then MMIO base might not be + * mapped causing the MMIO read below to fault. Faults can't + * be handled at that point. + */ + cmpl $0, x2apic_mode(%rip) + jz .Lread_apicid_mmio + + /* Force the AP into X2APIC mode. */ + orl $X2APIC_ENABLE, %eax + wrmsr + jmp .Lread_apicid_msr +#endif + +.Lread_apicid_mmio: /* Read the APIC ID from the fix-mapped MMIO space. */ movq apic_mmio_base(%rip), %rcx addq $APIC_ID, %rcx |