diff options
| author | Tom Lendacky <thomas.lendacky@amd.com> | 2018-03-28 01:07:11 +0300 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2018-03-28 11:42:57 +0300 |
| commit | 07344b15a994acadbe439aa4e75127ed1ccca099 (patch) | |
| tree | 2fe67e65764d6975111d44881fb5b513440710ff /arch/x86/boot/compressed/kaslr_64.c | |
| parent | 547edaca247abf910e32f0cd883ba83b8fc6d0ed (diff) | |
| download | linux-07344b15a994acadbe439aa4e75127ed1ccca099.tar.xz | |
x86/boot: Fix SEV boot failure from change to __PHYSICAL_MASK_SHIFT
In arch/x86/boot/compressed/kaslr_64.c, CONFIG_AMD_MEM_ENCRYPT support was
initially #undef'd to support SME with minimal effort. When support for
SEV was added, the #undef remained and some minimal support for setting the
encryption bit was added for building identity mapped pagetable entries.
Commit b83ce5ee9147 ("x86/mm/64: Make __PHYSICAL_MASK_SHIFT always 52")
changed __PHYSICAL_MASK_SHIFT from 46 to 52 in support of 5-level paging.
This change resulted in SEV guests failing to boot because the encryption
bit was no longer being automatically masked out. The compressed boot
path now requires sme_me_mask to be defined in order for the pagetable
functions, such as pud_present(), to properly mask out the encryption bit
(currently bit 47) when evaluating pagetable entries.
Add an sme_me_mask variable in arch/x86/boot/compressed/mem_encrypt.S,
which is set when SEV is active, delete the #undef CONFIG_AMD_MEM_ENCRYPT
from arch/x86/boot/compressed/kaslr_64.c and use sme_me_mask when building
the identify mapped pagetable entries.
Fixes: b83ce5ee9147 ("x86/mm/64: Make __PHYSICAL_MASK_SHIFT always 52")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20180327220711.8702.55842.stgit@tlendack-t1.amdoffice.net
Diffstat (limited to 'arch/x86/boot/compressed/kaslr_64.c')
| -rw-r--r-- | arch/x86/boot/compressed/kaslr_64.c | 14 |
1 files changed, 4 insertions, 10 deletions
diff --git a/arch/x86/boot/compressed/kaslr_64.c b/arch/x86/boot/compressed/kaslr_64.c index b5e5e02f8cde..522d11431433 100644 --- a/arch/x86/boot/compressed/kaslr_64.c +++ b/arch/x86/boot/compressed/kaslr_64.c @@ -16,13 +16,6 @@ #define __pa(x) ((unsigned long)(x)) #define __va(x) ((void *)((unsigned long)(x))) -/* - * The pgtable.h and mm/ident_map.c includes make use of the SME related - * information which is not used in the compressed image support. Un-define - * the SME support to avoid any compile and link errors. - */ -#undef CONFIG_AMD_MEM_ENCRYPT - /* No PAGE_TABLE_ISOLATION support needed either: */ #undef CONFIG_PAGE_TABLE_ISOLATION @@ -85,13 +78,14 @@ static struct x86_mapping_info mapping_info; /* Locates and clears a region for a new top level page table. */ void initialize_identity_maps(void) { - unsigned long sev_me_mask = get_sev_encryption_mask(); + /* If running as an SEV guest, the encryption mask is required. */ + set_sev_encryption_mask(); /* Init mapping_info with run-time function/buffer pointers. */ mapping_info.alloc_pgt_page = alloc_pgt_page; mapping_info.context = &pgt_data; - mapping_info.page_flag = __PAGE_KERNEL_LARGE_EXEC | sev_me_mask; - mapping_info.kernpg_flag = _KERNPG_TABLE | sev_me_mask; + mapping_info.page_flag = __PAGE_KERNEL_LARGE_EXEC | sme_me_mask; + mapping_info.kernpg_flag = _KERNPG_TABLE; /* * It should be impossible for this not to already be true, |