x86/mm/pat: Make set_memory_np() L1TF safe (958f79b9) · Commits · 戴 / test

set_memory_np() is used to mark kernel mappings not present, but it has it's own open coded mechanism which does not have the L1TF protection of inverting the address bits. Replace the open coded PTE manipulation with the L1TF protecting low level PTE routines. Passes the CPA self test. Signed-off-by:

Andi Kleen <ak@linux.intel.com> Signed-off-by:

Thomas Gleixner <tglx@linutronix.de>

arch/x86/mm/pageattr.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -1014,8 +1014,8 @@ static long populate_pmd(struct cpa_data *cpa,

		pmd = pmd_offset(pud, start);

		set_pmd(pmd, __pmd(cpa->pfn << PAGE_SHIFT \| _PAGE_PSE \|
		massage_pgprot(pmd_pgprot)));
		set_pmd(pmd, pmd_mkhuge(pfn_pmd(cpa->pfn,
		canon_pgprot(pmd_pgprot))));

		start += PMD_SIZE;
		cpa->pfn += PMD_SIZE >> PAGE_SHIFT;
		@@ -1087,8 +1087,8 @@ static int populate_pud(struct cpa_data cpa, unsigned long start, p4d_t p4d,
		* Map everything starting from the Gb boundary, possibly with 1G pages
		*/
		while (boot_cpu_has(X86_FEATURE_GBPAGES) && end - start >= PUD_SIZE) {
		set_pud(pud, __pud(cpa->pfn << PAGE_SHIFT \| _PAGE_PSE \|
		massage_pgprot(pud_pgprot)));
		set_pud(pud, pud_mkhuge(pfn_pud(cpa->pfn,
		canon_pgprot(pud_pgprot))));

		start += PUD_SIZE;
		cpa->pfn += PUD_SIZE >> PAGE_SHIFT;

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