Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux

Pull ARM updates from Russell King:

 - Updates to AMBA bus subsystem to drop .owner struct device_driver
   initialisations, moving that to code instead.

 - Add LPAE privileged-access-never support

 - Add support for Clang CFI

 - clkdev: report over-sized device or connection strings

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux: (36 commits)
  ARM: 9398/1: Fix userspace enter on LPAE with CC_OPTIMIZE_FOR_SIZE=y
  clkdev: report over-sized strings when creating clkdev entries
  ARM: 9393/1: mm: Use conditionals for CFI branches
  ARM: 9392/2: Support CLANG CFI
  ARM: 9391/2: hw_breakpoint: Handle CFI breakpoints
  ARM: 9390/2: lib: Annotate loop delay instructions for CFI
  ARM: 9389/2: mm: Define prototypes for all per-processor calls
  ARM: 9388/2: mm: Type-annotate all per-processor assembly routines
  ARM: 9387/2: mm: Rewrite cacheflush vtables in CFI safe C
  ARM: 9386/2: mm: Use symbol alias for cache functions
  ARM: 9385/2: mm: Type-annotate all cache assembly routines
  ARM: 9384/2: mm: Make tlbflush routines CFI safe
  ARM: 9382/1: ftrace: Define ftrace_stub_graph
  ARM: 9358/2: Implement PAN for LPAE by TTBR0 page table walks disablement
  ARM: 9357/2: Reduce the number of #ifdef CONFIG_CPU_SW_DOMAIN_PAN
  ARM: 9356/2: Move asm statements accessing TTBCR into C functions
  ARM: 9355/2: Add TTBCR_* definitions to pgtable-3level-hwdef.h
  ARM: 9379/1: coresight: tpda: drop owner assignment
  ARM: 9378/1: coresight: etm4x: drop owner assignment
  ARM: 9377/1: hwrng: nomadik: drop owner assignment
  ...

1 files changed, 39 insertions, 6 deletions

diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
index 9556d04387f7..6c9c16d767cf 100644
--- a/arch/arm/include/asm/uaccess.h
+++ b/arch/arm/include/asm/uaccess.h
@@ -14,6 +14,8 @@
 #include <asm/domain.h>
 #include <asm/unaligned.h>
 #include <asm/unified.h>
+#include <asm/pgtable.h>
+#include <asm/proc-fns.h>
 #include <asm/compiler.h>
 
 #include <asm/extable.h>
@@ -24,9 +26,10 @@
  * perform such accesses (eg, via list poison values) which could then
  * be exploited for priviledge escalation.
  */
+#if defined(CONFIG_CPU_SW_DOMAIN_PAN)
+
 static __always_inline unsigned int uaccess_save_and_enable(void)
 {
-#ifdef CONFIG_CPU_SW_DOMAIN_PAN
 	unsigned int old_domain = get_domain();
 
 	/* Set the current domain access to permit user accesses */
@@ -34,19 +37,49 @@ static __always_inline unsigned int uaccess_save_and_enable(void)
 		   domain_val(DOMAIN_USER, DOMAIN_CLIENT));
 
 	return old_domain;
-#else
-	return 0;
-#endif
 }
 
 static __always_inline void uaccess_restore(unsigned int flags)
 {
-#ifdef CONFIG_CPU_SW_DOMAIN_PAN
 	/* Restore the user access mask */
 	set_domain(flags);
-#endif
 }
 
+#elif defined(CONFIG_CPU_TTBR0_PAN)
+
+static __always_inline unsigned int uaccess_save_and_enable(void)
+{
+	unsigned int old_ttbcr = cpu_get_ttbcr();
+
+	/*
+	 * Enable TTBR0 page table walks (T0SZ = 0, EDP0 = 0) and ASID from
+	 * TTBR0 (A1 = 0).
+	 */
+	cpu_set_ttbcr(old_ttbcr & ~(TTBCR_A1 | TTBCR_EPD0 | TTBCR_T0SZ_MASK));
+	isb();
+
+	return old_ttbcr;
+}
+
+static inline void uaccess_restore(unsigned int flags)
+{
+	cpu_set_ttbcr(flags);
+	isb();
+}
+
+#else
+
+static inline unsigned int uaccess_save_and_enable(void)
+{
+	return 0;
+}
+
+static inline void uaccess_restore(unsigned int flags)
+{
+}
+
+#endif
+
 /*
  * These two are intentionally not defined anywhere - if the kernel
  * code generates any references to them, that's a bug.