diff options
| -rw-r--r-- | arch/x86/power/hibernate_64.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/arch/x86/power/hibernate_64.c b/arch/x86/power/hibernate_64.c index f2598d81cd55..f910c514438f 100644 --- a/arch/x86/power/hibernate_64.c +++ b/arch/x86/power/hibernate_64.c @@ -295,7 +295,26 @@ int arch_hibernation_header_save(void *addr, unsigned int max_size) return -EOVERFLOW; rdr->jump_address = (unsigned long)restore_registers; rdr->jump_address_phys = __pa_symbol(restore_registers); - rdr->cr3 = restore_cr3; + + /* + * The restore code fixes up CR3 and CR4 in the following sequence: + * + * [in hibernation asm] + * 1. CR3 <= temporary page tables + * 2. CR4 <= mmu_cr4_features (from the kernel that restores us) + * 3. CR3 <= rdr->cr3 + * 4. CR4 <= mmu_cr4_features (from us, i.e. the image kernel) + * [in restore_processor_state()] + * 5. CR4 <= saved CR4 + * 6. CR3 <= saved CR3 + * + * Our mmu_cr4_features has CR4.PCIDE=0, and toggling + * CR4.PCIDE while CR3's PCID bits are nonzero is illegal, so + * rdr->cr3 needs to point to valid page tables but must not + * have any of the PCID bits set. + */ + rdr->cr3 = restore_cr3 & ~CR3_PCID_MASK; + rdr->magic = RESTORE_MAGIC; hibernation_e820_save(rdr->e820_digest); |