Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
  kgdboc,tty: Fix tty polling search to use name correctly
  kgdb, x86_64: fix PS CS SS registers in gdb serial
  kgdb, x86_64: gdb serial has BX and DX reversed
  kgdb, x86, arm, mips, powerpc: ignore user space single stepping
  kgdb: could not write to the last of valid memory with kgdb

7 files changed, 63 insertions, 38 deletions

diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c
index aaffaecffcd1..ba8ccfede964 100644
--- a/arch/arm/kernel/kgdb.c
+++ b/arch/arm/kernel/kgdb.c
@@ -111,8 +111,6 @@ int kgdb_arch_handle_exception(int exception_vector, int signo,
         case 'D':
         case 'k':
         case 'c':
-                kgdb_contthread = NULL;
-
                 /*
                  * Try to read optional parameter, pc unchanged if no parm.
                  * If this was a compiled breakpoint, we need to move
diff --git a/arch/mips/kernel/kgdb.c b/arch/mips/kernel/kgdb.c
index 8f6d58ede33c..6e152c80cd4a 100644
--- a/arch/mips/kernel/kgdb.c
+++ b/arch/mips/kernel/kgdb.c
@@ -236,8 +236,7 @@ int kgdb_arch_handle_exception(int vector, int signo, int err_code,
 
                 atomic_set(&kgdb_cpu_doing_single_step, -1);
                 if (remcom_in_buffer[0] == 's')
-                        if (kgdb_contthread)
-                                atomic_set(&kgdb_cpu_doing_single_step, cpu);
+                        atomic_set(&kgdb_cpu_doing_single_step, cpu);
 
                 return 0;
         }
diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
index b4fdf2f2743c..fe8f71dd0b3f 100644
--- a/arch/powerpc/kernel/kgdb.c
+++ b/arch/powerpc/kernel/kgdb.c
@@ -347,9 +347,8 @@ int kgdb_arch_handle_exception(int vector, int signo, int err_code,
                         linux_regs->msr |= MSR_SE;
 #endif
                         kgdb_single_step = 1;
-                        if (kgdb_contthread)
-                                atomic_set(&kgdb_cpu_doing_single_step,
-                                           raw_smp_processor_id());
+                        atomic_set(&kgdb_cpu_doing_single_step,
+                                   raw_smp_processor_id());
                 }
                 return 0;
         }
diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index f47f0eb886b8..8282a2139681 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -69,6 +69,9 @@ static int gdb_x86vector = -1;
  */
 void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
 {
+#ifndef CONFIG_X86_32
+        u32 *gdb_regs32 = (u32 *)gdb_regs;
+#endif
         gdb_regs[GDB_AX]        = regs->ax;
         gdb_regs[GDB_BX]        = regs->bx;
         gdb_regs[GDB_CX]        = regs->cx;
@@ -76,9 +79,9 @@ void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
         gdb_regs[GDB_SI]        = regs->si;
         gdb_regs[GDB_DI]        = regs->di;
         gdb_regs[GDB_BP]        = regs->bp;
-        gdb_regs[GDB_PS]        = regs->flags;
         gdb_regs[GDB_PC]        = regs->ip;
 #ifdef CONFIG_X86_32
+        gdb_regs[GDB_PS]        = regs->flags;
         gdb_regs[GDB_DS]        = regs->ds;
         gdb_regs[GDB_ES]        = regs->es;
         gdb_regs[GDB_CS]        = regs->cs;
@@ -94,6 +97,9 @@ void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
         gdb_regs[GDB_R13]       = regs->r13;
         gdb_regs[GDB_R14]       = regs->r14;
         gdb_regs[GDB_R15]       = regs->r15;
+        gdb_regs32[GDB_PS]      = regs->flags;
+        gdb_regs32[GDB_CS]      = regs->cs;
+        gdb_regs32[GDB_SS]      = regs->ss;
 #endif
         gdb_regs[GDB_SP]        = regs->sp;
 }
@@ -112,6 +118,9 @@ void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
  */
 void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
 {
+#ifndef CONFIG_X86_32
+        u32 *gdb_regs32 = (u32 *)gdb_regs;
+#endif
         gdb_regs[GDB_AX]        = 0;
         gdb_regs[GDB_BX]        = 0;
         gdb_regs[GDB_CX]        = 0;
@@ -129,8 +138,10 @@ void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
         gdb_regs[GDB_FS]        = 0xFFFF;
         gdb_regs[GDB_GS]        = 0xFFFF;
 #else
-        gdb_regs[GDB_PS]        = *(unsigned long *)(p->thread.sp + 8);
-        gdb_regs[GDB_PC]        = 0;
+        gdb_regs32[GDB_PS]      = *(unsigned long *)(p->thread.sp + 8);
+        gdb_regs32[GDB_CS]      = __KERNEL_CS;
+        gdb_regs32[GDB_SS]      = __KERNEL_DS;
+        gdb_regs[GDB_PC]        = p->thread.ip;
         gdb_regs[GDB_R8]        = 0;
         gdb_regs[GDB_R9]        = 0;
         gdb_regs[GDB_R10]       = 0;
@@ -153,6 +164,9 @@ void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
  */
 void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
 {
+#ifndef CONFIG_X86_32
+        u32 *gdb_regs32 = (u32 *)gdb_regs;
+#endif
         regs->ax                = gdb_regs[GDB_AX];
         regs->bx                = gdb_regs[GDB_BX];
         regs->cx                = gdb_regs[GDB_CX];
@@ -160,9 +174,9 @@ void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
         regs->si                = gdb_regs[GDB_SI];
         regs->di                = gdb_regs[GDB_DI];
         regs->bp                = gdb_regs[GDB_BP];
-        regs->flags             = gdb_regs[GDB_PS];
         regs->ip                = gdb_regs[GDB_PC];
 #ifdef CONFIG_X86_32
+        regs->flags             = gdb_regs[GDB_PS];
         regs->ds                = gdb_regs[GDB_DS];
         regs->es                = gdb_regs[GDB_ES];
         regs->cs                = gdb_regs[GDB_CS];
@@ -175,6 +189,9 @@ void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
         regs->r13               = gdb_regs[GDB_R13];
         regs->r14               = gdb_regs[GDB_R14];
         regs->r15               = gdb_regs[GDB_R15];
+        regs->flags             = gdb_regs32[GDB_PS];
+        regs->cs                = gdb_regs32[GDB_CS];
+        regs->ss                = gdb_regs32[GDB_SS];
 #endif
 }
 
@@ -378,10 +395,8 @@ int kgdb_arch_handle_exception(int e_vector, int signo, int err_code,
                 if (remcomInBuffer[0] == 's') {
                         linux_regs->flags |= X86_EFLAGS_TF;
                         kgdb_single_step = 1;
-                        if (kgdb_contthread) {
-                                atomic_set(&kgdb_cpu_doing_single_step,
-                                           raw_smp_processor_id());
-                        }
+                        atomic_set(&kgdb_cpu_doing_single_step,
+                                   raw_smp_processor_id());
                 }
 
                 get_debugreg(dr6, 6);
@@ -466,9 +481,15 @@ static int __kgdb_notify(struct die_args *args, unsigned long cmd)
 
         case DIE_DEBUG:
                 if (atomic_read(&kgdb_cpu_doing_single_step) ==
-                        raw_smp_processor_id() &&
-                        user_mode(regs))
-                        return single_step_cont(regs, args);
+                    raw_smp_processor_id()) {
+                        if (user_mode(regs))
+                                return single_step_cont(regs, args);
+                        break;
+                } else if (test_thread_flag(TIF_SINGLESTEP))
+                        /* This means a user thread is single stepping
+                         * a system call which should be ignored
+                         */
+                        return NOTIFY_DONE;
                 /* fall through */
         default:
                 if (user_mode(regs))
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index daeb8f766971..e4dce8709541 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -695,13 +695,23 @@ struct tty_driver *tty_find_polling_driver(char *name, int *line)
 {
         struct tty_driver *p, *res = NULL;
         int tty_line = 0;
+        int len;
         char *str;
 
+        for (str = name; *str; str++)
+                if ((*str >= '0' && *str <= '9') || *str == ',')
+                        break;
+        if (!*str)
+                return NULL;
+
+        len = str - name;
+        tty_line = simple_strtoul(str, &str, 10);
+
         mutex_lock(&tty_mutex);
         /* Search through the tty devices to look for a match */
         list_for_each_entry(p, &tty_drivers, tty_drivers) {
-                str = name + strlen(p->name);
-                tty_line = simple_strtoul(str, &str, 10);
+                if (strncmp(name, p->name, len) != 0)
+                        continue;
                 if (*str == ',')
                         str++;
                 if (*str == '\0')
diff --git a/include/asm-x86/kgdb.h b/include/asm-x86/kgdb.h
index 484c47554f3b..94d63db10365 100644
--- a/include/asm-x86/kgdb.h
+++ b/include/asm-x86/kgdb.h
@@ -39,12 +39,13 @@ enum regnames {
         GDB_FS,                 /* 14 */
         GDB_GS,                 /* 15 */
 };
+#define NUMREGBYTES             ((GDB_GS+1)*4)
 #else /* ! CONFIG_X86_32 */
-enum regnames {
+enum regnames64 {
         GDB_AX,                 /* 0 */
-        GDB_DX,                 /* 1 */
+        GDB_BX,                 /* 1 */
         GDB_CX,                 /* 2 */
-        GDB_BX,                 /* 3 */
+        GDB_DX,                 /* 3 */
         GDB_SI,                 /* 4 */
         GDB_DI,                 /* 5 */
         GDB_BP,                 /* 6 */
@@ -58,18 +59,15 @@ enum regnames {
         GDB_R14,                /* 14 */
         GDB_R15,                /* 15 */
         GDB_PC,                 /* 16 */
-        GDB_PS,                 /* 17 */
 };
-#endif /* CONFIG_X86_32 */
 
-/*
- * Number of bytes of registers:
- */
-#ifdef CONFIG_X86_32
-# define NUMREGBYTES            64
-#else
-# define NUMREGBYTES            ((GDB_PS+1)*8)
-#endif
+enum regnames32 {
+        GDB_PS = 34,
+        GDB_CS,
+        GDB_SS,
+};
+#define NUMREGBYTES             ((GDB_SS+1)*4)
+#endif /* CONFIG_X86_32 */
 
 static inline void arch_kgdb_breakpoint(void)
 {
diff --git a/kernel/kgdb.c b/kernel/kgdb.c
index eaa21fc9ad1d..25d955dbb989 100644
--- a/kernel/kgdb.c
+++ b/kernel/kgdb.c
@@ -488,7 +488,7 @@ static int write_mem_msg(int binary)
                 if (err)
                         return err;
                 if (CACHE_FLUSH_IS_SAFE)
-                        flush_icache_range(addr, addr + length + 1);
+                        flush_icache_range(addr, addr + length);
                 return 0;
         }
 
@@ -1462,7 +1462,7 @@ acquirelock:
          * Get the passive CPU lock which will hold all the non-primary
          * CPU in a spin state while the debugger is active
          */
-        if (!kgdb_single_step || !kgdb_contthread) {
+        if (!kgdb_single_step) {
                 for (i = 0; i < NR_CPUS; i++)
                         atomic_set(&passive_cpu_wait[i], 1);
         }
@@ -1475,7 +1475,7 @@ acquirelock:
 
 #ifdef CONFIG_SMP
         /* Signal the other CPUs to enter kgdb_wait() */
-        if ((!kgdb_single_step || !kgdb_contthread) && kgdb_do_roundup)
+        if ((!kgdb_single_step) && kgdb_do_roundup)
                 kgdb_roundup_cpus(flags);
 #endif
 
@@ -1494,7 +1494,7 @@ acquirelock:
         kgdb_post_primary_code(ks->linux_regs, ks->ex_vector, ks->err_code);
         kgdb_deactivate_sw_breakpoints();
         kgdb_single_step = 0;
-        kgdb_contthread = NULL;
+        kgdb_contthread = current;
         exception_level = 0;
 
         /* Talk to debugger with gdbserial protocol */
@@ -1508,7 +1508,7 @@ acquirelock:
         kgdb_info[ks->cpu].task = NULL;
         atomic_set(&cpu_in_kgdb[ks->cpu], 0);
 
-        if (!kgdb_single_step || !kgdb_contthread) {
+        if (!kgdb_single_step) {
                 for (i = NR_CPUS-1; i >= 0; i--)
                         atomic_set(&passive_cpu_wait[i], 0);
                 /*