Merge branch 'aarch64/for-next/debug-virtual' into aarch64/for-next/core

Merge core DEBUG_VIRTUAL changes from Laura Abbott. Later arm and arm64
support depends on these.

* aarch64/for-next/debug-virtual:
  drivers: firmware: psci: Use __pa_symbol for kernel symbol
  mm/usercopy: Switch to using lm_alias
  mm/kasan: Switch to using __pa_symbol and lm_alias
  kexec: Switch to __pa_symbol
  mm: Introduce lm_alias
  mm/cma: Cleanup highmem check
  lib/Kconfig.debug: Add ARCH_HAS_DEBUG_VIRTUAL

3 files changed, 15 insertions, 19 deletions

diff --git a/mm/cma.c b/mm/cma.c
index c960459eda7e..94b3460cd608 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -235,18 +235,13 @@ int __init cma_declare_contiguous(phys_addr_t base,
 	phys_addr_t highmem_start;
 	int ret = 0;
 
-#ifdef CONFIG_X86
 	/*
-	 * high_memory isn't direct mapped memory so retrieving its physical
-	 * address isn't appropriate.  But it would be useful to check the
-	 * physical address of the highmem boundary so it's justifiable to get
-	 * the physical address from it.  On x86 there is a validation check for
-	 * this case, so the following workaround is needed to avoid it.
+	 * We can't use __pa(high_memory) directly, since high_memory
+	 * isn't a valid direct map VA, and DEBUG_VIRTUAL will (validly)
+	 * complain. Find the boundary by adding one to the last valid
+	 * address.
 	 */
-	highmem_start = __pa_nodebug(high_memory);
-#else
-	highmem_start = __pa(high_memory);
-#endif
+	highmem_start = __pa(high_memory - 1) + 1;
 	pr_debug("%s(size %pa, base %pa, limit %pa alignment %pa)\n",
 		__func__, &size, &base, &limit, &alignment);
 
diff --git a/mm/kasan/kasan_init.c b/mm/kasan/kasan_init.c
index 3f9a41cf0ac6..31238dad85fb 100644
--- a/mm/kasan/kasan_init.c
+++ b/mm/kasan/kasan_init.c
@@ -15,6 +15,7 @@
 #include <linux/kasan.h>
 #include <linux/kernel.h>
 #include <linux/memblock.h>
+#include <linux/mm.h>
 #include <linux/pfn.h>
 
 #include <asm/page.h>
@@ -49,7 +50,7 @@ static void __init zero_pte_populate(pmd_t *pmd, unsigned long addr,
 	pte_t *pte = pte_offset_kernel(pmd, addr);
 	pte_t zero_pte;
 
-	zero_pte = pfn_pte(PFN_DOWN(__pa(kasan_zero_page)), PAGE_KERNEL);
+	zero_pte = pfn_pte(PFN_DOWN(__pa_symbol(kasan_zero_page)), PAGE_KERNEL);
 	zero_pte = pte_wrprotect(zero_pte);
 
 	while (addr + PAGE_SIZE <= end) {
@@ -69,7 +70,7 @@ static void __init zero_pmd_populate(pud_t *pud, unsigned long addr,
 		next = pmd_addr_end(addr, end);
 
 		if (IS_ALIGNED(addr, PMD_SIZE) && end - addr >= PMD_SIZE) {
-			pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte);
+			pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte));
 			continue;
 		}
 
@@ -92,9 +93,9 @@ static void __init zero_pud_populate(pgd_t *pgd, unsigned long addr,
 		if (IS_ALIGNED(addr, PUD_SIZE) && end - addr >= PUD_SIZE) {
 			pmd_t *pmd;
 
-			pud_populate(&init_mm, pud, kasan_zero_pmd);
+			pud_populate(&init_mm, pud, lm_alias(kasan_zero_pmd));
 			pmd = pmd_offset(pud, addr);
-			pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte);
+			pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte));
 			continue;
 		}
 
@@ -135,11 +136,11 @@ void __init kasan_populate_zero_shadow(const void *shadow_start,
 			 * puds,pmds, so pgd_populate(), pud_populate()
 			 * is noops.
 			 */
-			pgd_populate(&init_mm, pgd, kasan_zero_pud);
+			pgd_populate(&init_mm, pgd, lm_alias(kasan_zero_pud));
 			pud = pud_offset(pgd, addr);
-			pud_populate(&init_mm, pud, kasan_zero_pmd);
+			pud_populate(&init_mm, pud, lm_alias(kasan_zero_pmd));
 			pmd = pmd_offset(pud, addr);
-			pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte);
+			pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte));
 			continue;
 		}
 
diff --git a/mm/usercopy.c b/mm/usercopy.c
index 3c8da0af9695..8345299e3e3b 100644
--- a/mm/usercopy.c
+++ b/mm/usercopy.c
@@ -108,13 +108,13 @@ static inline const char *check_kernel_text_object(const void *ptr,
 	 * __pa() is not just the reverse of __va(). This can be detected
 	 * and checked:
 	 */
-	textlow_linear = (unsigned long)__va(__pa(textlow));
+	textlow_linear = (unsigned long)lm_alias(textlow);
 	/* No different mapping: we're done. */
 	if (textlow_linear == textlow)
 		return NULL;
 
 	/* Check the secondary mapping... */
-	texthigh_linear = (unsigned long)__va(__pa(texthigh));
+	texthigh_linear = (unsigned long)lm_alias(texthigh);
 	if (overlaps(ptr, n, textlow_linear, texthigh_linear))
 		return "<linear kernel text>";