Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into for-linus-1

* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6: (9356 commits)
  [media] rc: update for bitop name changes
  fs: simplify iget & friends
  fs: pull inode->i_lock up out of writeback_single_inode
  fs: rename inode_lock to inode_hash_lock
  fs: move i_wb_list out from under inode_lock
  fs: move i_sb_list out from under inode_lock
  fs: remove inode_lock from iput_final and prune_icache
  fs: Lock the inode LRU list separately
  fs: factor inode disposal
  fs: protect inode->i_state with inode->i_lock
  lib, arch: add filter argument to show_mem and fix private implementations
  SLUB: Write to per cpu data when allocating it
  slub: Fix debugobjects with lockless fastpath
  autofs4: Do not potentially dereference NULL pointer returned by fget() in autofs_dev_ioctl_setpipefd()
  autofs4 - remove autofs4_lock
  autofs4 - fix d_manage() return on rcu-walk
  autofs4 - fix autofs4_expire_indirect() traversal
  autofs4 - fix dentry leak in autofs4_expire_direct()
  autofs4 - reinstate last used update on access
  vfs - check non-mountpoint dentry might block in __follow_mount_rcu()
  ...

NOTE!

This merge commit was created to fix compilation error. The block
tree was merged upstream and removed the 'elv_queue_empty()'
function which the new 'mtdswap' driver is using. So a simple
merge of the mtd tree with upstream does not compile. And the
mtd tree has already be published, so re-basing it is not an option.

To fix this unfortunate situation, I had to merge upstream into the
mtd-2.6.git tree without committing, put the fixup patch on top of
this, and then commit this. The result is that we do not have commits
which do not compile.

In other words, this merge commit "merges" 3 things: the MTD tree, the
upstream tree, and the fixup patch.

1 files changed, 54 insertions, 26 deletions

diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c
index c9f3f04..8dbc126 100644
--- a/arch/arm/kernel/hw_breakpoint.c
+++ b/arch/arm/kernel/hw_breakpoint.c
@@ -137,11 +137,10 @@ static u8 get_debug_arch(void)
 	u32 didr;
 
 	/* Do we implement the extended CPUID interface? */
-	if (((read_cpuid_id() >> 16) & 0xf) != 0xf) {
-		pr_warning("CPUID feature registers not supported. "
-				"Assuming v6 debug is present.\n");
+	if (WARN_ONCE((((read_cpuid_id() >> 16) & 0xf) != 0xf),
+	    "CPUID feature registers not supported. "
+	    "Assuming v6 debug is present.\n"))
 		return ARM_DEBUG_ARCH_V6;
-	}
 
 	ARM_DBG_READ(c0, 0, didr);
 	return (didr >> 16) & 0xf;
@@ -152,6 +151,12 @@ u8 arch_get_debug_arch(void)
 	return debug_arch;
 }
 
+static int debug_arch_supported(void)
+{
+	u8 arch = get_debug_arch();
+	return arch >= ARM_DEBUG_ARCH_V6 && arch <= ARM_DEBUG_ARCH_V7_ECP14;
+}
+
 /* Determine number of BRP register available. */
 static int get_num_brp_resources(void)
 {
@@ -233,8 +238,8 @@ static int enable_monitor_mode(void)
 	ARM_DBG_READ(c1, 0, dscr);
 
 	/* Ensure that halting mode is disabled. */
-	if (WARN_ONCE(dscr & ARM_DSCR_HDBGEN, "halting debug mode enabled."
-				"Unable to access hardware resources.")) {
+	if (WARN_ONCE(dscr & ARM_DSCR_HDBGEN,
+			"halting debug mode enabled. Unable to access hardware resources.\n")) {
 		ret = -EPERM;
 		goto out;
 	}
@@ -268,6 +273,9 @@ out:
 
 int hw_breakpoint_slots(int type)
 {
+	if (!debug_arch_supported())
+		return 0;
+
 	/*
 	 * We can be called early, so don't rely on
 	 * our static variables being initialised.
@@ -369,7 +377,7 @@ int arch_install_hw_breakpoint(struct perf_event *bp)
 		}
 	}
 
-	if (WARN_ONCE(i == max_slots, "Can't find any breakpoint slot")) {
+	if (WARN_ONCE(i == max_slots, "Can't find any breakpoint slot\n")) {
 		ret = -EBUSY;
 		goto out;
 	}
@@ -415,7 +423,7 @@ void arch_uninstall_hw_breakpoint(struct perf_event *bp)
 		}
 	}
 
-	if (WARN_ONCE(i == max_slots, "Can't find any breakpoint slot"))
+	if (WARN_ONCE(i == max_slots, "Can't find any breakpoint slot\n"))
 		return;
 
 	/* Reset the control register. */
@@ -627,7 +635,7 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
 	if (WARN_ONCE(!bp->overflow_handler &&
 		(arch_check_bp_in_kernelspace(bp) || !core_has_mismatch_brps()
 		 || !bp->hw.bp_target),
-			"overflow handler required but none found")) {
+			"overflow handler required but none found\n")) {
 		ret = -EINVAL;
 	}
 out:
@@ -828,20 +836,33 @@ static int hw_breakpoint_pending(unsigned long addr, unsigned int fsr,
 /*
  * One-time initialisation.
  */
-static void reset_ctrl_regs(void *unused)
+static void reset_ctrl_regs(void *info)
 {
-	int i;
+	int i, cpu = smp_processor_id();
+	u32 dbg_power;
+	cpumask_t *cpumask = info;
 
 	/*
 	 * v7 debug contains save and restore registers so that debug state
-	 * can be maintained across low-power modes without leaving
-	 * the debug logic powered up. It is IMPLEMENTATION DEFINED whether
-	 * we can write to the debug registers out of reset, so we must
-	 * unlock the OS Lock Access Register to avoid taking undefined
-	 * instruction exceptions later on.
+	 * can be maintained across low-power modes without leaving the debug
+	 * logic powered up. It is IMPLEMENTATION DEFINED whether we can access
+	 * the debug registers out of reset, so we must unlock the OS Lock
+	 * Access Register to avoid taking undefined instruction exceptions
+	 * later on.
 	 */
 	if (debug_arch >= ARM_DEBUG_ARCH_V7_ECP14) {
 		/*
+		 * Ensure sticky power-down is clear (i.e. debug logic is
+		 * powered up).
+		 */
+		asm volatile("mrc p14, 0, %0, c1, c5, 4" : "=r" (dbg_power));
+		if ((dbg_power & 0x1) == 0) {
+			pr_warning("CPU %d debug is powered down!\n", cpu);
+			cpumask_or(cpumask, cpumask, cpumask_of(cpu));
+			return;
+		}
+
+		/*
 		 * Unconditionally clear the lock by writing a value
 		 * other than 0xC5ACCE55 to the access register.
 		 */
@@ -879,10 +900,11 @@ static struct notifier_block __cpuinitdata dbg_reset_nb = {
 static int __init arch_hw_breakpoint_init(void)
 {
 	u32 dscr;
+	cpumask_t cpumask = { CPU_BITS_NONE };
 
 	debug_arch = get_debug_arch();
 
-	if (debug_arch > ARM_DEBUG_ARCH_V7_ECP14) {
+	if (!debug_arch_supported()) {
 		pr_info("debug architecture 0x%x unsupported.\n", debug_arch);
 		return 0;
 	}
@@ -899,18 +921,24 @@ static int __init arch_hw_breakpoint_init(void)
 		pr_info("%d breakpoint(s) reserved for watchpoint "
 				"single-step.\n", core_num_reserved_brps);
 
+	/*
+	 * Reset the breakpoint resources. We assume that a halting
+	 * debugger will leave the world in a nice state for us.
+	 */
+	on_each_cpu(reset_ctrl_regs, &cpumask, 1);
+	if (!cpumask_empty(&cpumask)) {
+		core_num_brps = 0;
+		core_num_reserved_brps = 0;
+		core_num_wrps = 0;
+		return 0;
+	}
+
 	ARM_DBG_READ(c1, 0, dscr);
 	if (dscr & ARM_DSCR_HDBGEN) {
-		pr_warning("halting debug mode enabled. Assuming maximum "
-				"watchpoint size of 4 bytes.");
+		max_watchpoint_len = 4;
+		pr_warning("halting debug mode enabled. Assuming maximum watchpoint size of %u bytes.\n",
+			   max_watchpoint_len);
 	} else {
-		/*
-		 * Reset the breakpoint resources. We assume that a halting
-		 * debugger will leave the world in a nice state for us.
-		 */
-		smp_call_function(reset_ctrl_regs, NULL, 1);
-		reset_ctrl_regs(NULL);
-
 		/* Work out the maximum supported watchpoint length. */
 		max_watchpoint_len = get_max_wp_len();
 		pr_info("maximum watchpoint size is %u bytes.\n",