diff options
| author | Joerg Roedel <jroedel@suse.de> | 2020-09-07 15:15:17 +0200 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2020-09-07 19:45:25 +0200 |
| commit | ca0e22d4f011a56e974fa3a712d76e86a791559d (patch) | |
| tree | 6a4f203a78723d5e52d3d140fd2fac516cbe0ead /arch/x86/boot/compressed/head_64.S | |
| parent | 8b0d3b3b41ab6f14f1ce6d4a6b1c5f60b825123f (diff) | |
x86/boot/compressed/64: Always switch to own page table
When booted through startup_64(), the kernel keeps running on the EFI
page table until the KASLR code sets up its own page table. Without
KASLR, the pre-decompression boot code never switches off the EFI page
table. Change that by unconditionally switching to a kernel-controlled
page table after relocation.
This makes sure the kernel can make changes to the mapping when
necessary, for example map pages unencrypted in SEV and SEV-ES guests.
Also, remove the debug_putstr() calls in initialize_identity_maps()
because the function now runs before console_init() is called.
[ bp: Massage commit message. ]
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20200907131613.12703-17-joro@8bytes.org
Diffstat (limited to 'arch/x86/boot/compressed/head_64.S')
| -rw-r--r-- | arch/x86/boot/compressed/head_64.S | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index c634ed8636da..fb6c0392306b 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -543,10 +543,11 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated) rep stosq /* - * Load stage2 IDT + * Load stage2 IDT and switch to our own page-table */ pushq %rsi call load_stage2_idt + call initialize_identity_maps popq %rsi /* |