diff options
| -rw-r--r-- | arch/x86/kernel/head_64.S | 31 | ||||
| -rw-r--r-- | drivers/virt/coco/sev-guest/sev-guest.c | 6 |
2 files changed, 24 insertions, 13 deletions
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 0f8103240fda..f479e5e793a2 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -114,6 +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) @@ -193,15 +215,6 @@ 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 diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c index bc564adcf499..87f241825bc3 100644 --- a/drivers/virt/coco/sev-guest/sev-guest.c +++ b/drivers/virt/coco/sev-guest/sev-guest.c @@ -994,7 +994,7 @@ e_unmap: return ret; } -static int __exit sev_guest_remove(struct platform_device *pdev) +static void __exit sev_guest_remove(struct platform_device *pdev) { struct snp_guest_dev *snp_dev = platform_get_drvdata(pdev); @@ -1003,8 +1003,6 @@ static int __exit sev_guest_remove(struct platform_device *pdev) free_shared_pages(snp_dev->request, sizeof(struct snp_guest_msg)); deinit_crypto(snp_dev->crypto); misc_deregister(&snp_dev->misc); - - return 0; } /* @@ -1013,7 +1011,7 @@ static int __exit sev_guest_remove(struct platform_device *pdev) * with the SEV-SNP support, it is named "sev-guest". */ static struct platform_driver sev_guest_driver = { - .remove = __exit_p(sev_guest_remove), + .remove_new = __exit_p(sev_guest_remove), .driver = { .name = "sev-guest", }, |