4 files changed, 110 insertions, 11 deletions

diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index 871b8267d211..a586cfe7b4e4 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -10,7 +10,6 @@
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
-#include <linux/compiler.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/dma-mapping.h>
@@ -41,19 +40,10 @@
  * GCC 3.2.x: miscompiles NEW_AUX_ENT in fs/binfmt_elf.c
  *            (http://gcc.gnu.org/PR8896) and incorrect structure
  *	      initialisation in fs/jffs2/erase.c
- * GCC 4.8.0-4.8.2: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58854
- *	      miscompiles find_get_entry(), and can result in EXT3 and EXT4
- *	      filesystem corruption (possibly other FS too).
  */
-#ifdef __GNUC__
 #if (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
 #error Your compiler is too buggy; it is known to miscompile kernels.
-#error    Known good compilers: 3.3, 4.x
-#endif
-#if GCC_VERSION >= 40800 && GCC_VERSION < 40803
-#error Your compiler is too buggy; it is known to miscompile kernels
-#error and result in filesystem corruption and oopses.
-#endif
+#error    Known good compilers: 3.3
 #endif
 
 int main(void)
diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c
index 9232caee7060..f3c662299531 100644
--- a/arch/arm/kernel/kgdb.c
+++ b/arch/arm/kernel/kgdb.c
@@ -140,6 +140,8 @@ int kgdb_arch_handle_exception(int exception_vector, int signo,
 
 static int kgdb_brk_fn(struct pt_regs *regs, unsigned int instr)
 {
+	if (user_mode(regs))
+		return -1;
 	kgdb_handle_exception(1, SIGTRAP, 0, regs);
 
 	return 0;
@@ -147,6 +149,8 @@ static int kgdb_brk_fn(struct pt_regs *regs, unsigned int instr)
 
 static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int instr)
 {
+	if (user_mode(regs))
+		return -1;
 	compiled_break = 1;
 	kgdb_handle_exception(1, SIGTRAP, 0, regs);
 
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index 4adfb46e3ee9..0017b3edfea8 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -80,6 +80,7 @@ void arch_cpu_idle_prepare(void)
 
 void arch_cpu_idle_enter(void)
 {
+	idle_notifier_call_chain(IDLE_START);
 	ledtrig_cpu(CPU_LED_IDLE_START);
 #ifdef CONFIG_PL310_ERRATA_769419
 	wmb();
@@ -89,6 +90,78 @@ void arch_cpu_idle_enter(void)
 void arch_cpu_idle_exit(void)
 {
 	ledtrig_cpu(CPU_LED_IDLE_END);
+	idle_notifier_call_chain(IDLE_END);
+}
+
+/*
+ * dump a block of kernel memory from around the given address
+ */
+static void show_data(unsigned long addr, int nbytes, const char *name)
+{
+	int	i, j;
+	int	nlines;
+	u32	*p;
+
+	/*
+	 * don't attempt to dump non-kernel addresses or
+	 * values that are probably just small negative numbers
+	 */
+	if (addr < PAGE_OFFSET || addr > -256UL)
+		return;
+
+	printk("\n%s: %#lx:\n", name, addr);
+
+	/*
+	 * round address down to a 32 bit boundary
+	 * and always dump a multiple of 32 bytes
+	 */
+	p = (u32 *)(addr & ~(sizeof(u32) - 1));
+	nbytes += (addr & (sizeof(u32) - 1));
+	nlines = (nbytes + 31) / 32;
+
+
+	for (i = 0; i < nlines; i++) {
+		/*
+		 * just display low 16 bits of address to keep
+		 * each line of the dump < 80 characters
+		 */
+		printk("%04lx ", (unsigned long)p & 0xffff);
+		for (j = 0; j < 8; j++) {
+			u32	data;
+			if (probe_kernel_address(p, data)) {
+				printk(" ********");
+			} else {
+				printk(" %08x", data);
+			}
+			++p;
+		}
+		printk("\n");
+	}
+}
+
+static void show_extra_register_data(struct pt_regs *regs, int nbytes)
+{
+	mm_segment_t fs;
+
+	fs = get_fs();
+	set_fs(KERNEL_DS);
+	show_data(regs->ARM_pc - nbytes, nbytes * 2, "PC");
+	show_data(regs->ARM_lr - nbytes, nbytes * 2, "LR");
+	show_data(regs->ARM_sp - nbytes, nbytes * 2, "SP");
+	show_data(regs->ARM_ip - nbytes, nbytes * 2, "IP");
+	show_data(regs->ARM_fp - nbytes, nbytes * 2, "FP");
+	show_data(regs->ARM_r0 - nbytes, nbytes * 2, "R0");
+	show_data(regs->ARM_r1 - nbytes, nbytes * 2, "R1");
+	show_data(regs->ARM_r2 - nbytes, nbytes * 2, "R2");
+	show_data(regs->ARM_r3 - nbytes, nbytes * 2, "R3");
+	show_data(regs->ARM_r4 - nbytes, nbytes * 2, "R4");
+	show_data(regs->ARM_r5 - nbytes, nbytes * 2, "R5");
+	show_data(regs->ARM_r6 - nbytes, nbytes * 2, "R6");
+	show_data(regs->ARM_r7 - nbytes, nbytes * 2, "R7");
+	show_data(regs->ARM_r8 - nbytes, nbytes * 2, "R8");
+	show_data(regs->ARM_r9 - nbytes, nbytes * 2, "R9");
+	show_data(regs->ARM_r10 - nbytes, nbytes * 2, "R10");
+	set_fs(fs);
 }
 
 void __show_regs(struct pt_regs *regs)
@@ -178,6 +251,8 @@ void __show_regs(struct pt_regs *regs)
 		printk("Control: %08x%s\n", ctrl, buf);
 	}
 #endif
+
+	show_extra_register_data(regs, 128);
 }
 
 void show_regs(struct pt_regs * regs)
diff --git a/arch/arm/kernel/reboot.c b/arch/arm/kernel/reboot.c
index 38269358fd25..1a06da8f0366 100644
--- a/arch/arm/kernel/reboot.c
+++ b/arch/arm/kernel/reboot.c
@@ -6,6 +6,7 @@
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
+#include <linux/console.h>
 #include <linux/cpu.h>
 #include <linux/delay.h>
 #include <linux/reboot.h>
@@ -124,6 +125,31 @@ void machine_power_off(void)
 		pm_power_off();
 }
 
+#ifdef CONFIG_ARM_FLUSH_CONSOLE_ON_RESTART
+void arm_machine_flush_console(void)
+{
+	printk("\n");
+	pr_emerg("Restarting %s\n", linux_banner);
+	if (console_trylock()) {
+		console_unlock();
+		return;
+	}
+
+	mdelay(50);
+
+	local_irq_disable();
+	if (!console_trylock())
+		pr_emerg("arm_restart: Console was locked! Busting\n");
+	else
+		pr_emerg("arm_restart: Console was locked!\n");
+	console_unlock();
+}
+#else
+void arm_machine_flush_console(void)
+{
+}
+#endif
+
 /*
  * Restart requires that the secondary CPUs stop performing any activity
  * while the primary CPU resets the system. Systems with a single CPU can
@@ -140,6 +166,10 @@ void machine_restart(char *cmd)
 	local_irq_disable();
 	smp_send_stop();
 
+	/* Flush the console to make sure all the relevant messages make it
+	 * out to the console drivers */
+	arm_machine_flush_console();
+
 	if (arm_pm_restart)
 		arm_pm_restart(reboot_mode, cmd);
 	else