diff options
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/pat/set_memory.c | 23 |
1 files changed, 11 insertions, 12 deletions
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index 0caf4b0edcbc..44f0d4260bd8 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -1925,14 +1925,9 @@ int set_memory_wb(unsigned long addr, int numpages) } EXPORT_SYMBOL(set_memory_wb); -/* - * 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). - */ +/* Prevent speculative access to a page by marking it not-present */ #ifdef CONFIG_X86_64 -int set_mce_nospec(unsigned long pfn, bool unmap) +int set_mce_nospec(unsigned long pfn) { unsigned long decoy_addr; int rc; @@ -1954,19 +1949,23 @@ int set_mce_nospec(unsigned long pfn, bool unmap) */ 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); + rc = set_memory_np(decoy_addr, 1); if (rc) pr_warn("Could not invalidate pfn=0x%lx from 1:1 map\n", pfn); return rc; } +static int set_memory_present(unsigned long *addr, int numpages) +{ + return change_page_attr_set(addr, numpages, __pgprot(_PAGE_PRESENT), 0); +} + /* Restore full speculative operation to the pfn. */ int clear_mce_nospec(unsigned long pfn) { - return set_memory_wb((unsigned long) pfn_to_kaddr(pfn), 1); + unsigned long addr = (unsigned long) pfn_to_kaddr(pfn); + + return set_memory_present(&addr, 1); } EXPORT_SYMBOL_GPL(clear_mce_nospec); #endif /* CONFIG_X86_64 */ |