Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linu…

…x-2.6

* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
  [S390] cio: Call cancel_halt_clear even when actl == 0.
  [S390] cio: Use path verification to check for path state.
  [S390] cio: Fix locking when calling notify function.
  [S390] Fixed handling of access register mode faults.
  [S390] dasd: Use default recovery for SNSS requests
  [S390] check_bugs() should be inline.
  [S390] tape: Compression overwrites crypto setting
  [S390] nss: disable kexec.
  [S390] reipl: move dump_prefix_page out of text section.
  [S390] smp: disable preemption in smp_call_function/smp_call_function_on
  [S390] kprobes breaks BUG_ON

arch/s390/Kconfig

@@ -376,6 +376,8 @@ config SHARED_KERNEL
 	  Select this option, if you want to share the text segment of the
 	  Linux kernel between different VM guests. This reduces memory
 	  usage with lots of guests but greatly increases kernel size.
+	  Also if a kernel was IPL'ed from a shared segment the kexec system
+	  call will not work.
 	  You should only select this option if you know what you are
 	  doing and want to exploit this feature.
 

arch/s390/kernel/head31.S

@@ -121,7 +121,7 @@ startup_continue:
 	.long	.Lduct			# cr2: dispatchable unit control table
 	.long	0			# cr3: instruction authorization
 	.long	0			# cr4: instruction authorization
-	.long	0xffffffff		# cr5: primary-aste origin
+	.long	.Lduct			# cr5: primary-aste origin
 	.long	0			# cr6:	I/O interrupts
 	.long	0			# cr7:	secondary space segment table
 	.long	0			# cr8:	access registers translation
@@ -132,8 +132,6 @@ startup_continue:
 	.long	0			# cr13: home space segment table
 	.long	0xc0000000		# cr14: machine check handling off
 	.long	0			# cr15: linkage stack operations
-.Lduct:	.long	0,0,0,0,0,0,0,0
-	.long	0,0,0,0,0,0,0,0
 .Lpcfpu:.long	0x00080000,0x80000000 + .Lchkfpu
 .Lpccsp:.long	0x00080000,0x80000000 + .Lchkcsp
 .Lpcmvpg:.long	0x00080000,0x80000000 + .Lchkmvpg
@@ -147,6 +145,13 @@ startup_continue:
 .Linittu:   .long init_thread_union
 .Lstartup_init:
 	    .long startup_init
+	.align	64
+.Lduct:	.long	0,0,0,0,.Lduald,0,0,0
+	.long	0,0,0,0,0,0,0,0
+	.align	128
+.Lduald:.rept	8
+	.long	0x80000000,0,0,0	# invalid access-list entries
+	.endr
 
 	.org	0x12000
 	.globl	_ehead

arch/s390/kernel/head64.S

@@ -134,7 +134,7 @@ startup_continue:
 	.quad	.Lduct			# cr2: dispatchable unit control table
 	.quad	0			# cr3: instruction authorization
 	.quad	0			# cr4: instruction authorization
-	.quad	0xffffffffffffffff	# cr5: primary-aste origin
+	.quad	.Lduct			# cr5: primary-aste origin
 	.quad	0			# cr6:	I/O interrupts
 	.quad	0			# cr7:	secondary space segment table
 	.quad	0			# cr8:	access registers translation
@@ -145,14 +145,19 @@ startup_continue:
 	.quad	0			# cr13: home space segment table
 	.quad	0xc0000000		# cr14: machine check handling off
 	.quad	0			# cr15: linkage stack operations
-.Lduct: .long	0,0,0,0,0,0,0,0
-	.long	0,0,0,0,0,0,0,0
 .Lpcmsk:.quad	0x0000000180000000
 .L4malign:.quad 0xffffffffffc00000
 .Lscan2g:.quad	0x80000000 + 0x20000 - 8	# 2GB + 128K - 8
 .Lnop:	.long	0x07000700
 .Lparmaddr:
 	.quad	PARMAREA
+	.align	64
+.Lduct: .long	0,0,0,0,.Lduald,0,0,0
+	.long	0,0,0,0,0,0,0,0
+	.align	128
+.Lduald:.rept	8
+	.long	0x80000000,0,0,0	# invalid access-list entries
+	.endr
 
 	.org	0x12000
 	.globl	_ehead

arch/s390/kernel/ipl.c

@@ -1066,7 +1066,7 @@ static void do_reset_calls(void)
 		reset->fn();
 }
 
-extern __u32 dump_prefix_page;
+u32 dump_prefix_page;
 
 void s390_reset_system(void)
 {
@@ -1078,7 +1078,7 @@ void s390_reset_system(void)
 	lc->panic_stack = S390_lowcore.panic_stack;
 
 	/* Save prefix page address for dump case */
-	dump_prefix_page = (unsigned long) lc;
+	dump_prefix_page = (u32)(unsigned long) lc;
 
 	/* Disable prefixing */
 	set_prefix(0);

arch/s390/kernel/kprobes.c

@@ -337,21 +337,14 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 	}
 
 	p = get_kprobe(addr);
-	if (!p) {
-		if (*addr != BREAKPOINT_INSTRUCTION) {
-			/*
-			 * The breakpoint instruction was removed right
-			 * after we hit it.  Another cpu has removed
-			 * either a probepoint or a debugger breakpoint
-			 * at this address.  In either case, no further
-			 * handling of this interrupt is appropriate.
-			 *
-			 */
-			ret = 1;
-		}
-		/* Not one of ours: let kernel handle it */
+	if (!p)
+		/*
+		 * No kprobe at this address. The fault has not been
+		 * caused by a kprobe breakpoint. The race of breakpoint
+		 * vs. kprobe remove does not exist because on s390 we
+		 * use stop_machine_run to arm/disarm the breakpoints.
+		 */
 		goto no_kprobe;
-	}
 
 	kcb->kprobe_status = KPROBE_HIT_ACTIVE;
 	set_current_kprobe(p, regs, kcb);

arch/s390/kernel/machine_kexec.c

@@ -19,6 +19,7 @@
 #include <asm/system.h>
 #include <asm/smp.h>
 #include <asm/reset.h>
+#include <asm/ipl.h>
 
 typedef void (*relocate_kernel_t)(kimage_entry_t *, unsigned long);
 
@@ -29,6 +30,10 @@ int machine_kexec_prepare(struct kimage *image)
 {
 	void *reboot_code_buffer;
 
+	/* Can't replace kernel image since it is read-only. */
+	if (ipl_flags & IPL_NSS_VALID)
+		return -ENOSYS;
+
 	/* We don't support anything but the default image type for now. */
 	if (image->type != KEXEC_TYPE_DEFAULT)
 		return -EINVAL;

arch/s390/kernel/reipl.S

@@ -8,6 +8,10 @@
 
 #include <asm/lowcore.h>
 
+#
+# do_reipl_asm
+# Parameter: r2 = schid of reipl device
+#
 		.globl	do_reipl_asm
 do_reipl_asm:	basr	%r13,0
 .Lpg0:		lpsw	.Lnewpsw-.Lpg0(%r13)
@@ -16,12 +20,12 @@ do_reipl_asm:	basr	%r13,0
 		stm	%r0,%r15,__LC_GPREGS_SAVE_AREA
 		stctl	%c0,%c15,__LC_CREGS_SAVE_AREA
 		stam	%a0,%a15,__LC_AREGS_SAVE_AREA
-		mvc	__LC_PREFIX_SAVE_AREA(4),dump_prefix_page-.Lpg0(%r13)
+		l	%r10,.Ldump_pfx-.Lpg0(%r13)
+		mvc	__LC_PREFIX_SAVE_AREA(4),0(%r10)
 		stckc	.Lclkcmp-.Lpg0(%r13)
 		mvc	__LC_CLOCK_COMP_SAVE_AREA(8),.Lclkcmp-.Lpg0(%r13)
 		stpt	__LC_CPU_TIMER_SAVE_AREA
 		st	%r13, __LC_PSW_SAVE_AREA+4
-
 		lctl	%c6,%c6,.Lall-.Lpg0(%r13)
 		lr	%r1,%r2
 		mvc	__LC_PGM_NEW_PSW(8),.Lpcnew-.Lpg0(%r13)
@@ -55,6 +59,7 @@ do_reipl_asm:	basr	%r13,0
 		.align	8
 .Lclkcmp:	.quad	0x0000000000000000
 .Lall:		.long	0xff000000
+.Ldump_pfx:	.long	dump_prefix_page
 		.align	8
 .Lnewpsw:	.long	0x00080000,0x80000000+.Lpg1
 .Lpcnew:	.long	0x00080000,0x80000000+.Lecs
@@ -79,7 +84,3 @@ do_reipl_asm:	basr	%r13,0
 		.long	0x00000000,0x00000000
 		.long	0x00000000,0x00000000
 		.long	0x00000000,0x00000000
-	.globl dump_prefix_page
-dump_prefix_page:
-	.long 0x00000000
-

arch/s390/kernel/reipl64.S

@@ -8,6 +8,12 @@
  */
 
 #include <asm/lowcore.h>
+
+#
+# do_reipl_asm
+# Parameter: r2 = schid of reipl device
+#
+
 		.globl	do_reipl_asm
 do_reipl_asm:	basr	%r13,0
 .Lpg0:		lpswe	.Lnewpsw-.Lpg0(%r13)
@@ -20,7 +26,8 @@ do_reipl_asm:	basr	%r13,0
 		stg	%r0,__LC_GPREGS_SAVE_AREA-0x1000+8(%r1)
 		stctg	%c0,%c15,__LC_CREGS_SAVE_AREA-0x1000(%r1)
 		stam	%a0,%a15,__LC_AREGS_SAVE_AREA-0x1000(%r1)
-		mvc	__LC_PREFIX_SAVE_AREA-0x1000(4,%r1),dump_prefix_page-.Lpg0(%r13)
+		lg	%r10,.Ldump_pfx-.Lpg0(%r13)
+		mvc	__LC_PREFIX_SAVE_AREA-0x1000(4,%r1),0(%r10)
 		stfpc	__LC_FP_CREG_SAVE_AREA-0x1000(%r1)
 		stckc	.Lclkcmp-.Lpg0(%r13)
 		mvc	__LC_CLOCK_COMP_SAVE_AREA-0x1000(8,%r1),.Lclkcmp-.Lpg0(%r13)
@@ -64,6 +71,7 @@ do_reipl_asm:	basr	%r13,0
 		.align	8
 .Lclkcmp:	.quad	0x0000000000000000
 .Lall:		.quad	0x00000000ff000000
+.Ldump_pfx:	.quad	dump_prefix_page
 .Lregsave:	.quad	0x0000000000000000
 		.align	16
 /*
@@ -103,6 +111,3 @@ do_reipl_asm:	basr	%r13,0
 		.long	0x00000000,0x00000000
 		.long	0x00000000,0x00000000
 		.long	0x00000000,0x00000000
-	.globl dump_prefix_page
-dump_prefix_page:
-	.long 0x00000000

arch/s390/kernel/smp.c

@@ -94,10 +94,9 @@ static void __smp_call_function_map(void (*func) (void *info), void *info,
 	int cpu, local = 0;
 
 	/*
-	 * Can deadlock when interrupts are disabled or if in wrong context,
-	 * caller must disable preemption
+	 * Can deadlock when interrupts are disabled or if in wrong context.
 	 */
-	WARN_ON(irqs_disabled() || in_irq() || preemptible());
+	WARN_ON(irqs_disabled() || in_irq());
 
 	/*
 	 * Check for local function call. We have to have the same call order
@@ -152,17 +151,18 @@ static void __smp_call_function_map(void (*func) (void *info), void *info,
  * Run a function on all other CPUs.
  *
  * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler. Must be called with preemption disabled.
- * You may call it from a bottom half.
+ * hardware interrupt handler. You may call it from a bottom half.
  */
 int smp_call_function(void (*func) (void *info), void *info, int nonatomic,
 		      int wait)
 {
 	cpumask_t map;
 
+	preempt_disable();
 	map = cpu_online_map;
 	cpu_clear(smp_processor_id(), map);
 	__smp_call_function_map(func, info, nonatomic, wait, map);
+	preempt_enable();
 	return 0;
 }
 EXPORT_SYMBOL(smp_call_function);
@@ -178,16 +178,17 @@ EXPORT_SYMBOL(smp_call_function);
  * Run a function on one processor.
  *
  * You must not call this function with disabled interrupts or from a
- * hardware interrupt handler. Must be called with preemption disabled.
- * You may call it from a bottom half.
+ * hardware interrupt handler. You may call it from a bottom half.
  */
 int smp_call_function_on(void (*func) (void *info), void *info, int nonatomic,
 			  int wait, int cpu)
 {
 	cpumask_t map = CPU_MASK_NONE;
 
+	preempt_disable();
 	cpu_set(cpu, map);
 	__smp_call_function_map(func, info, nonatomic, wait, map);
+	preempt_enable();
 	return 0;
 }
 EXPORT_SYMBOL(smp_call_function_on);