aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/include/asm/set_memory.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/include/asm/set_memory.h')
-rw-r--r--arch/x86/include/asm/set_memory.h52
1 files changed, 0 insertions, 52 deletions
diff --git a/arch/x86/include/asm/set_memory.h b/arch/x86/include/asm/set_memory.h
index 78ca53512486..b45c4d27fd46 100644
--- a/arch/x86/include/asm/set_memory.h
+++ b/arch/x86/include/asm/set_memory.h
@@ -86,56 +86,4 @@ bool kernel_page_present(struct page *page);
extern int kernel_set_to_readonly;
-#ifdef CONFIG_X86_64
-/*
- * Prevent speculative access to the page by either unmapping
- * it (if we do not require access to any part of the page) or
- * marking it uncacheable (if we want to try to retrieve data
- * from non-poisoned lines in the page).
- */
-static inline int set_mce_nospec(unsigned long pfn, bool unmap)
-{
- unsigned long decoy_addr;
- int rc;
-
- /* SGX pages are not in the 1:1 map */
- if (arch_is_platform_page(pfn << PAGE_SHIFT))
- return 0;
- /*
- * We would like to just call:
- * set_memory_XX((unsigned long)pfn_to_kaddr(pfn), 1);
- * but doing that would radically increase the odds of a
- * speculative access to the poison page because we'd have
- * the virtual address of the kernel 1:1 mapping sitting
- * around in registers.
- * Instead we get tricky. We create a non-canonical address
- * that looks just like the one we want, but has bit 63 flipped.
- * This relies on set_memory_XX() properly sanitizing any __pa()
- * results with __PHYSICAL_MASK or PTE_PFN_MASK.
- */
- decoy_addr = (pfn << PAGE_SHIFT) + (PAGE_OFFSET ^ BIT(63));
-
- if (unmap)
- rc = set_memory_np(decoy_addr, 1);
- else
- rc = set_memory_uc(decoy_addr, 1);
- if (rc)
- pr_warn("Could not invalidate pfn=0x%lx from 1:1 map\n", pfn);
- return rc;
-}
-#define set_mce_nospec set_mce_nospec
-
-/* Restore full speculative operation to the pfn. */
-static inline int clear_mce_nospec(unsigned long pfn)
-{
- return set_memory_wb((unsigned long) pfn_to_kaddr(pfn), 1);
-}
-#define clear_mce_nospec clear_mce_nospec
-#else
-/*
- * Few people would run a 32-bit kernel on a machine that supports
- * recoverable errors because they have too much memory to boot 32-bit.
- */
-#endif
-
#endif /* _ASM_X86_SET_MEMORY_H */