Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "Three arm64 fixes for -rc3.

  We've plugged a couple of nasty issues involving KASLR-enabled
  kernels, and removed a redundant #define that was introduced as part
  of the KHWASAN fixes from akpm at -rc2.

   - Fix broken kpti page-table rewrite in bizarre KASLR configuration

   - Fix module loading with KASLR

   - Remove redundant definition of ARCH_SLAB_MINALIGN"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  kasan, arm64: remove redundant ARCH_SLAB_MINALIGN define
  arm64: kaslr: ensure randomized quantities are clean to the PoC
  arm64: kpti: Update arm64_kernel_use_ng_mappings() when forced on

3 files changed, 10 insertions, 5 deletions

diff --git a/arch/arm64/include/asm/cache.h b/arch/arm64/include/asm/cache.h
index eb43e09c1980..926434f413fa 100644
--- a/arch/arm64/include/asm/cache.h
+++ b/arch/arm64/include/asm/cache.h
@@ -60,8 +60,6 @@
 
 #ifdef CONFIG_KASAN_SW_TAGS
 #define ARCH_SLAB_MINALIGN      (1ULL << KASAN_SHADOW_SCALE_SHIFT)
-#else
-#define ARCH_SLAB_MINALIGN      __alignof__(unsigned long long)
 #endif
 
 #ifndef __ASSEMBLY__
diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h
index ac352accb3d9..3e8063f4f9d3 100644
--- a/arch/arm64/include/asm/mmu.h
+++ b/arch/arm64/include/asm/mmu.h
@@ -60,8 +60,11 @@ static inline bool arm64_kernel_use_ng_mappings(void)
          * later determine that kpti is required, then
          * kpti_install_ng_mappings() will make them non-global.
          */
+        if (arm64_kernel_unmapped_at_el0())
+                return true;
+
         if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
-                return arm64_kernel_unmapped_at_el0();
+                return false;
 
         /*
          * KASLR is enabled so we're going to be enabling kpti on non-broken
diff --git a/arch/arm64/kernel/kaslr.c b/arch/arm64/kernel/kaslr.c
index f0e6ab8abe9c..ba6b41790fcd 100644
--- a/arch/arm64/kernel/kaslr.c
+++ b/arch/arm64/kernel/kaslr.c
@@ -14,6 +14,7 @@
 #include <linux/sched.h>
 #include <linux/types.h>
 
+#include <asm/cacheflush.h>
 #include <asm/fixmap.h>
 #include <asm/kernel-pgtable.h>
 #include <asm/memory.h>
@@ -43,7 +44,7 @@ static __init u64 get_kaslr_seed(void *fdt)
         return ret;
 }
 
-static __init const u8 *get_cmdline(void *fdt)
+static __init const u8 *kaslr_get_cmdline(void *fdt)
 {
         static __initconst const u8 default_cmdline[] = CONFIG_CMDLINE;
 
@@ -109,7 +110,7 @@ u64 __init kaslr_early_init(u64 dt_phys)
          * Check if 'nokaslr' appears on the command line, and
          * return 0 if that is the case.
          */
-        cmdline = get_cmdline(fdt);
+        cmdline = kaslr_get_cmdline(fdt);
         str = strstr(cmdline, "nokaslr");
         if (str == cmdline || (str > cmdline && *(str - 1) == ' '))
                 return 0;
@@ -169,5 +170,8 @@ u64 __init kaslr_early_init(u64 dt_phys)
         module_alloc_base += (module_range * (seed & ((1 << 21) - 1))) >> 21;
         module_alloc_base &= PAGE_MASK;
 
+        __flush_dcache_area(&module_alloc_base, sizeof(module_alloc_base));
+        __flush_dcache_area(&memstart_offset_seed, sizeof(memstart_offset_seed));
+
         return offset;
 }