Merge branch 'perf/core' into perf/uprobes

Merge in latest upstream (and the latest perf development tree),
to prepare for tooling changes, and also to pick up v3.4 MM
changes that the uprobes code needs to take care of.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 64 insertions, 3 deletions

diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index faba5771aca..8bfb6146f75 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -43,10 +43,11 @@
 #include <linux/smp.h>
 #include <linux/nmi.h>
 #include <linux/hw_breakpoint.h>
+#include <linux/uaccess.h>
+#include <linux/memory.h>
 
 #include <asm/debugreg.h>
 #include <asm/apicdef.h>
-#include <asm/system.h>
 #include <asm/apic.h>
 #include <asm/nmi.h>
 
@@ -67,8 +68,6 @@ struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] =
 	{ "ss", 4, offsetof(struct pt_regs, ss) },
 	{ "ds", 4, offsetof(struct pt_regs, ds) },
 	{ "es", 4, offsetof(struct pt_regs, es) },
-	{ "fs", 4, -1 },
-	{ "gs", 4, -1 },
 #else
 	{ "ax", 8, offsetof(struct pt_regs, ax) },
 	{ "bx", 8, offsetof(struct pt_regs, bx) },
@@ -90,7 +89,11 @@ struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] =
 	{ "flags", 4, offsetof(struct pt_regs, flags) },
 	{ "cs", 4, offsetof(struct pt_regs, cs) },
 	{ "ss", 4, offsetof(struct pt_regs, ss) },
+	{ "ds", 4, -1 },
+	{ "es", 4, -1 },
 #endif
+	{ "fs", 4, -1 },
+	{ "gs", 4, -1 },
 };
 
 int dbg_set_reg(int regno, void *mem, struct pt_regs *regs)
@@ -740,6 +743,64 @@ void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
 	regs->ip = ip;
 }
 
+int kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt)
+{
+	int err;
+	char opc[BREAK_INSTR_SIZE];
+
+	bpt->type = BP_BREAKPOINT;
+	err = probe_kernel_read(bpt->saved_instr, (char *)bpt->bpt_addr,
+				BREAK_INSTR_SIZE);
+	if (err)
+		return err;
+	err = probe_kernel_write((char *)bpt->bpt_addr,
+				 arch_kgdb_ops.gdb_bpt_instr, BREAK_INSTR_SIZE);
+#ifdef CONFIG_DEBUG_RODATA
+	if (!err)
+		return err;
+	/*
+	 * It is safe to call text_poke() because normal kernel execution
+	 * is stopped on all cores, so long as the text_mutex is not locked.
+	 */
+	if (mutex_is_locked(&text_mutex))
+		return -EBUSY;
+	text_poke((void *)bpt->bpt_addr, arch_kgdb_ops.gdb_bpt_instr,
+		  BREAK_INSTR_SIZE);
+	err = probe_kernel_read(opc, (char *)bpt->bpt_addr, BREAK_INSTR_SIZE);
+	if (err)
+		return err;
+	if (memcmp(opc, arch_kgdb_ops.gdb_bpt_instr, BREAK_INSTR_SIZE))
+		return -EINVAL;
+	bpt->type = BP_POKE_BREAKPOINT;
+#endif /* CONFIG_DEBUG_RODATA */
+	return err;
+}
+
+int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt)
+{
+#ifdef CONFIG_DEBUG_RODATA
+	int err;
+	char opc[BREAK_INSTR_SIZE];
+
+	if (bpt->type != BP_POKE_BREAKPOINT)
+		goto knl_write;
+	/*
+	 * It is safe to call text_poke() because normal kernel execution
+	 * is stopped on all cores, so long as the text_mutex is not locked.
+	 */
+	if (mutex_is_locked(&text_mutex))
+		goto knl_write;
+	text_poke((void *)bpt->bpt_addr, bpt->saved_instr, BREAK_INSTR_SIZE);
+	err = probe_kernel_read(opc, (char *)bpt->bpt_addr, BREAK_INSTR_SIZE);
+	if (err || memcmp(opc, bpt->saved_instr, BREAK_INSTR_SIZE))
+		goto knl_write;
+	return err;
+knl_write:
+#endif /* CONFIG_DEBUG_RODATA */
+	return probe_kernel_write((char *)bpt->bpt_addr,
+				  (char *)bpt->saved_instr, BREAK_INSTR_SIZE);
+}
+
 struct kgdb_arch arch_kgdb_ops = {
 	/* Breakpoint instruction: */
 	.gdb_bpt_instr		= { 0xcc },