Merge tag 'ronx-next' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into devel-stable

generic fixmaps
ARM support for CONFIG_DEBUG_RODATA

15 files changed, 394 insertions, 57 deletions

diff --git a/Documentation/arm/memory.txt b/Documentation/arm/memory.txt
index 38dc06d0a791..4178ebda6e66 100644
--- a/Documentation/arm/memory.txt
+++ b/Documentation/arm/memory.txt
@@ -41,7 +41,7 @@ fffe8000	fffeffff	DTCM mapping area for platforms with
 fffe0000        fffe7fff        ITCM mapping area for platforms with
                                 ITCM mounted inside the CPU.
 
-ffc00000        ffdfffff        Fixmap mapping region.  Addresses provided
+ffc00000        ffefffff        Fixmap mapping region.  Addresses provided
                                 by fix_to_virt() will be located here.
 
 fee00000        feffffff        Mapping of PCI I/O space. This is a static
diff --git a/arch/arm/include/asm/cacheflush.h b/arch/arm/include/asm/cacheflush.h
index 10e78d00a0bb..2d46862e7bef 100644
--- a/arch/arm/include/asm/cacheflush.h
+++ b/arch/arm/include/asm/cacheflush.h
@@ -487,6 +487,16 @@ int set_memory_rw(unsigned long addr, int numpages);
 int set_memory_x(unsigned long addr, int numpages);
 int set_memory_nx(unsigned long addr, int numpages);
 
+#ifdef CONFIG_DEBUG_RODATA
+void mark_rodata_ro(void);
+void set_kernel_text_rw(void);
+void set_kernel_text_ro(void);
+#else
+static inline void set_kernel_text_rw(void) { }
+static inline void set_kernel_text_ro(void) { }
+#endif
+
 void flush_uprobe_xol_access(struct page *page, unsigned long uaddr,
                              void *kaddr, unsigned long len);
+
 #endif
diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h
index 74124b0d0d79..0415eae1df27 100644
--- a/arch/arm/include/asm/fixmap.h
+++ b/arch/arm/include/asm/fixmap.h
@@ -2,27 +2,24 @@
 #define _ASM_FIXMAP_H
 
 #define FIXADDR_START           0xffc00000UL
-#define FIXADDR_TOP             0xffe00000UL
-#define FIXADDR_SIZE            (FIXADDR_TOP - FIXADDR_START)
+#define FIXADDR_END             0xfff00000UL
+#define FIXADDR_TOP             (FIXADDR_END - PAGE_SIZE)
 
-#define FIX_KMAP_NR_PTES        (FIXADDR_SIZE >> PAGE_SHIFT)
+#include <asm/kmap_types.h>
 
-#define __fix_to_virt(x)        (FIXADDR_START + ((x) << PAGE_SHIFT))
-#define __virt_to_fix(x)        (((x) - FIXADDR_START) >> PAGE_SHIFT)
+enum fixed_addresses {
+        FIX_KMAP_BEGIN,
+        FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
 
-extern void __this_fixmap_does_not_exist(void);
+        /* Support writing RO kernel text via kprobes, jump labels, etc. */
+        FIX_TEXT_POKE0,
+        FIX_TEXT_POKE1,
 
-static inline unsigned long fix_to_virt(const unsigned int idx)
-{
-        if (idx >= FIX_KMAP_NR_PTES)
-                __this_fixmap_does_not_exist();
-        return __fix_to_virt(idx);
-}
+        __end_of_fixed_addresses
+};
 
-static inline unsigned int virt_to_fix(const unsigned long vaddr)
-{
-        BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START);
-        return __virt_to_fix(vaddr);
-}
+void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
+
+#include <asm-generic/fixmap.h>
 
 #endif
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 38ddd9f83d0e..70b730766330 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -67,7 +67,7 @@ test-kprobes-objs		+= kprobes-test-arm.o
 endif
 obj-$(CONFIG_OABI_COMPAT)       += sys_oabi-compat.o
 obj-$(CONFIG_ARM_THUMBEE)       += thumbee.o
-obj-$(CONFIG_KGDB)              += kgdb.o
+obj-$(CONFIG_KGDB)              += kgdb.o patch.o
 obj-$(CONFIG_ARM_UNWIND)        += unwind.o
 obj-$(CONFIG_HAVE_TCM)          += tcm.o
 obj-$(CONFIG_OF)                += devtree.o
diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c
index af9a8a927a4e..b8c75e45a950 100644
--- a/arch/arm/kernel/ftrace.c
+++ b/arch/arm/kernel/ftrace.c
@@ -15,6 +15,7 @@
 #include <linux/ftrace.h>
 #include <linux/uaccess.h>
 #include <linux/module.h>
+#include <linux/stop_machine.h>
 
 #include <asm/cacheflush.h>
 #include <asm/opcodes.h>
@@ -35,6 +36,22 @@
 
 #define OLD_NOP         0xe1a00000      /* mov r0, r0 */
 
+static int __ftrace_modify_code(void *data)
+{
+        int *command = data;
+
+        set_kernel_text_rw();
+        ftrace_modify_all_code(*command);
+        set_kernel_text_ro();
+
+        return 0;
+}
+
+void arch_ftrace_update_code(int command)
+{
+        stop_machine(__ftrace_modify_code, &command, NULL);
+}
+
 static unsigned long ftrace_nop_replace(struct dyn_ftrace *rec)
 {
         return rec->arch.old_mcount ? OLD_NOP : NOP;
@@ -73,6 +90,8 @@ int ftrace_arch_code_modify_prepare(void)
 int ftrace_arch_code_modify_post_process(void)
 {
         set_all_modules_text_ro();
+        /* Make sure any TLB misses during machine stop are cleared. */
+        flush_tlb_all();
         return 0;
 }
 
diff --git a/arch/arm/kernel/jump_label.c b/arch/arm/kernel/jump_label.c
index 4ce4f789446d..afeeb9ea6f43 100644
--- a/arch/arm/kernel/jump_label.c
+++ b/arch/arm/kernel/jump_label.c
@@ -19,7 +19,7 @@ static void __arch_jump_label_transform(struct jump_entry *entry,
                 insn = arm_gen_nop();
 
         if (is_static)
-                __patch_text(addr, insn);
+                __patch_text_early(addr, insn);
         else
                 patch_text(addr, insn);
 }
diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c
index a74b53c1b7df..07db2f8a1b45 100644
--- a/arch/arm/kernel/kgdb.c
+++ b/arch/arm/kernel/kgdb.c
@@ -12,8 +12,12 @@
 #include <linux/irq.h>
 #include <linux/kdebug.h>
 #include <linux/kgdb.h>
+#include <linux/uaccess.h>
+
 #include <asm/traps.h>
 
+#include "patch.h"
+
 struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] =
 {