12 files changed, 291 insertions, 31 deletions

diff --git a/arch/s390/include/asm/debug.h b/arch/s390/include/asm/debug.h
index 9d88db1f55d0..8a8245ed14d2 100644
--- a/arch/s390/include/asm/debug.h
+++ b/arch/s390/include/asm/debug.h
@@ -131,6 +131,7 @@ void debug_unregister(debug_info_t* id);
 
 void debug_set_level(debug_info_t* id, int new_level);
 
+void debug_set_critical(void);
 void debug_stop_all(void);
 
 static inline debug_entry_t*
diff --git a/arch/s390/include/asm/ipl.h b/arch/s390/include/asm/ipl.h
index 6940abfbe1d9..2bd6cb897b90 100644
--- a/arch/s390/include/asm/ipl.h
+++ b/arch/s390/include/asm/ipl.h
@@ -169,5 +169,6 @@ enum diag308_rc {
 extern int diag308(unsigned long subcode, void *addr);
 extern void diag308_reset(void);
 extern void store_status(void);
+extern void lgr_info_log(void);
 
 #endif /* _ASM_S390_IPL_H */
diff --git a/arch/s390/include/asm/system.h b/arch/s390/include/asm/system.h
index d73cc6b60000..2e0bb7f0f9b2 100644
--- a/arch/s390/include/asm/system.h
+++ b/arch/s390/include/asm/system.h
@@ -7,8 +7,10 @@
 #ifndef __ASM_SYSTEM_H
 #define __ASM_SYSTEM_H
 
+#include <linux/preempt.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
+#include <linux/string.h>
 #include <asm/types.h>
 #include <asm/ptrace.h>
 #include <asm/setup.h>
@@ -248,6 +250,38 @@ static inline int test_facility(unsigned long nr)
         return (*ptr & (0x80 >> (nr & 7))) != 0;
 }
 
+/**
+ * stfle - Store facility list extended
+ * @stfle_fac_list: array where facility list can be stored
+ * @size: size of passed in array in double words
+ */
+static inline void stfle(u64 *stfle_fac_list, int size)
+{
+        unsigned long nr;
+
+        preempt_disable();
+        S390_lowcore.stfl_fac_list = 0;
+        asm volatile(
+                "       .insn s,0xb2b10000,0(0)\n" /* stfl */
+                "0:\n"
+                EX_TABLE(0b, 0b)
+                : "=m" (S390_lowcore.stfl_fac_list));
+        nr = 4; /* bytes stored by stfl */
+        memcpy(stfle_fac_list, &S390_lowcore.stfl_fac_list, 4);
+        if (S390_lowcore.stfl_fac_list & 0x01000000) {
+                /* More facility bits available with stfle */
+                register unsigned long reg0 asm("0") = size - 1;
+
+                asm volatile(".insn s,0xb2b00000,0(%1)" /* stfle */
+                             : "+d" (reg0)
+                             : "a" (stfle_fac_list)
+                             : "memory", "cc");
+                nr = (reg0 + 1) * 8; /* # bytes stored by stfle */
+        }
+        memset((char *) stfle_fac_list + nr, 0, size * 8 - nr);
+        preempt_enable();
+}
+
 static inline unsigned short stap(void)
 {
         unsigned short cpu_address;
diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
index d0a48268eb27..b21595090499 100644
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -23,7 +23,7 @@ CFLAGS_sysinfo.o += -Iinclude/math-emu -Iarch/s390/math-emu -w
 obj-y   :=  bitmap.o traps.o time.o process.o base.o early.o setup.o vtime.o \
             processor.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o nmi.o \
             debug.o irq.o ipl.o dis.o diag.o mem_detect.o sclp.o vdso.o \
-            sysinfo.o jump_label.o
+            sysinfo.o jump_label.o lgr.o
 
 obj-y   += $(if $(CONFIG_64BIT),entry64.o,entry.o)
 obj-y   += $(if $(CONFIG_64BIT),reipl64.o,reipl.o)
diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c
index 6848828b962e..19e5e9eba546 100644
--- a/arch/s390/kernel/debug.c
+++ b/arch/s390/kernel/debug.c
@@ -2,8 +2,8 @@
  *  arch/s390/kernel/debug.c
  *   S/390 debug facility
  *
- *    Copyright (C) 1999, 2000 IBM Deutschland Entwicklung GmbH,
- *                             IBM Corporation
+ *    Copyright IBM Corp. 1999, 2012
+ *
  *    Author(s): Michael Holzheu (holzheu@de.ibm.com),
  *               Holger Smolinski (Holger.Smolinski@de.ibm.com)
  *
@@ -167,6 +167,7 @@ static debug_info_t *debug_area_last = NULL;
 static DEFINE_MUTEX(debug_mutex);
 
 static int initialized;
+static int debug_critical;
 
 static const struct file_operations debug_file_ops = {
         .owner   = THIS_MODULE,
@@ -932,6 +933,11 @@ debug_stop_all(void)
 }
 
 
+void debug_set_critical(void)
+{
+        debug_critical = 1;
+}
+
 /*
  * debug_event_common:
  * - write debug entry with given size
@@ -945,7 +951,11 @@ debug_event_common(debug_info_t * id, int level, const void *buf, int len)
 
         if (!debug_active || !id->areas)
                 return NULL;
-        spin_lock_irqsave(&id->lock, flags);
+        if (debug_critical) {
+                if (!spin_trylock_irqsave(&id->lock, flags))
+                        return NULL;
+        } else
+                spin_lock_irqsave(&id->lock, flags);
         active = get_active_entry(id);
         memset(DEBUG_DATA(active), 0, id->buf_size);
         memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
@@ -968,7 +978,11 @@ debug_entry_t
 
         if (!debug_active || !id->areas)
                 return NULL;
-        spin_lock_irqsave(&id->lock, flags);
+        if (debug_critical) {
+                if (!spin_trylock_irqsave(&id->lock, flags))
+                        return NULL;
+        } else
+                spin_lock_irqsave(&id->lock, flags);
         active = get_active_entry(id);
         memset(DEBUG_DATA(active), 0, id->buf_size);
         memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
@@ -1013,7 +1027,11 @@ debug_sprintf_event(debug_info_t* id, int level,char *string,...)
                 return NULL;
         numargs=debug_count_numargs(string);
 
-        spin_lock_irqsave(&id->lock, flags);
+        if (debug_critical) {
+                if (!spin_trylock_irqsave(&id->lock, flags))
+                        return NULL;
+        } else
+                spin_lock_irqsave(&id->lock, flags);
         active = get_active_entry(id);
         curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active);
         va_start(ap,string);
@@ -1047,7 +1065,11 @@ debug_sprintf_exception(debug_info_t* id, int level,char *string,...)
 
         numargs=debug_count_numargs(string);
 
-        spin_lock_irqsave(&id->lock, flags);
+        if (debug_critical) {
+                if (!spin_trylock_irqsave(&id->lock, flags))
+                        return NULL;
+        } else
+                spin_lock_irqsave(&id->lock, flags);
         active = get_active_entry(id);
         curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active);
         va_start(ap,string);
@@ -1428,10 +1450,10 @@ debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
         rc += sprintf(out_buf + rc, "| ");
         for (i = 0; i < id->buf_size; i++) {
                 unsigned char c = in_buf[i];
-                if (!isprint(c))
-                        rc += sprintf(out_buf + rc, ".");
-                else
+                if (isascii(c) && isprint(c))
                         rc += sprintf(out_buf + rc, "%c", c);
+                else
+                        rc += sprintf(out_buf + rc, ".");
         }
         rc += sprintf(out_buf + rc, "\n");
         return rc;
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 52098d6dfaa7..578eb4e6d157 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -29,6 +29,7 @@
 #include <asm/sysinfo.h>
 #include <asm/cpcmd.h>
 #include <asm/sclp.h>
+#include <asm/system.h>
 #include "entry.h"
 
 /*
@@ -262,25 +263,8 @@ static noinline __init void setup_lowcore_early(void)
 
 static noinline __init void setup_facility_list(void)
 {
-        unsigned long nr;
-
-        S390_lowcore.stfl_fac_list = 0;
-        asm volatile(
-                "       .insn   s,0xb2b10000,0(0)\n" /* stfl */
-                "0:\n"
-                EX_TABLE(0b,0b) : "=m" (S390_lowcore.stfl_fac_list));
-        memcpy(&S390_lowcore.stfle_fac_list, &S390_lowcore.stfl_fac_list, 4);
-        nr = 4;                         /* # bytes stored by stfl */
-        if (test_facility(7)) {
-                /* More facility bits available with stfle */
-                register unsigned long reg0 asm("0") = MAX_FACILITY_BIT/64 - 1;
-                asm volatile(".insn s,0xb2b00000,%0" /* stfle */
-                             : "=m" (S390_lowcore.stfle_fac_list), "+d" (reg0)
-                             : : "cc");
-                nr = (reg0 + 1) * 8;    /* # bytes stored by stfle */
-        }
-        memset((char *) S390_lowcore.stfle_fac_list + nr, 0,
-               MAX_FACILITY_BIT/8 - nr);
+        stfle(S390_lowcore.stfle_fac_list,
+              ARRAY_SIZE(S390_lowcore.stfle_fac_list));
 }
 
 static noinline __init void setup_hpage(void)
diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c
index 9e2f6f7c0e5a..153e21ce2336 100644
--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -17,6 +17,7 @@
 #include <linux/fs.h>
 #include <linux/gfp.h>
 #include <linux/crash_dump.h>
+#include <linux/debug_locks.h>
 #include <asm/ipl.h>
 #include <asm/smp.h>
 #include <asm/setup.h>
@@ -26,6 +27,7 @@
 #include <asm/reset.h>
 #include <asm/sclp.h>
 #include <asm/checksum.h>
+#include <asm/debug.h>
 #include "entry.h"
 
 #define IPL_PARM_BLOCK_VERSION 0
@@ -1692,6 +1694,7 @@ static struct kobj_attribute on_panic_attr =
 
 static void do_panic(void)
 {
+        lgr_info_log();
         on_panic_trigger.action->fn(&on_panic_trigger);
         stop_run(&on_panic_trigger);
 }
@@ -1729,6 +1732,9 @@ static void __do_restart(void *ignore)
 
 void do_restart(void)
 {
+        tracing_off();
+        debug_locks_off();
+        lgr_info_log();
         smp_call_online_cpu(__do_restart, NULL);
 }
 
diff --git a/arch/s390/kernel/lgr.c b/arch/s390/kernel/lgr.c
new file mode 100644
index 000000000000..8431b92ca3ae
--- /dev/null
+++ b/arch/s390/kernel/lgr.c
@@ -0,0 +1,200 @@
+/*
+ * Linux Guest Relocation (LGR) detection
+ *
+ * Copyright IBM Corp. 2012
+ * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
+ */
+
+#include <linux/module.h>
+#include <linux/timer.h>
+#include <linux/slab.h>
+#include <asm/sysinfo.h>
+#include <asm/ebcdic.h>
+#include <asm/system.h>
+#include <asm/debug.h>
+#include <asm/ipl.h>
+
+#define LGR_TIMER_INTERVAL_SECS (30 * 60)
+#define VM_LEVEL_MAX 2 /* Maximum is 8, but we only record two levels */
+
+/*
+ * LGR info: Contains stfle and stsi data
+ */
+struct lgr_info {
+        /* Bit field with facility information: 4 DWORDs are stored */
+        u64 stfle_fac_list[4];
+        /* Level of system (1 = CEC, 2 = LPAR, 3 = z/VM */
+        u32 level;
+        /* Level 1: CEC info (stsi 1.1.1) */
+        char manufacturer[16];
+        char type[4];
+        char sequence[16];
+        char plant[4];
+        char model[16];
+        /* Level 2: LPAR info (stsi 2.2.2) */
+        u16 lpar_number;
+        char name[8];
+        /* Level 3: VM info (stsi 3.2.2) */
+        u8 vm_count;
+        struct {
+                char name[8];
+                char cpi[16];
+        } vm[VM_LEVEL_MAX];
+} __packed __aligned(8);
+
+/*
+ * LGR globals
+ */
+static void *lgr_page;
+static struct lgr_info lgr_info_last;
+static struct lgr_info lgr_info_cur;
+static struct debug_info *lgr_dbf;
+
+/*
+ * Return number of valid stsi levels
+ */
+static inline int stsi_0(void)
+{
+        int rc = stsi(NULL, 0, 0, 0);
+
+        return rc == -ENOSYS ? rc : (((unsigned int) rc) >> 28);
+}
+
+/*
+ * Copy buffer and then convert it to ASCII
+ */
+static void cpascii(char *dst, char *src, int size)
+{
+        memcpy(dst, src, size);
+        EBCASC(dst, size);
+}
+
+/*
+ * Fill LGR info with 1.1.1 stsi data
+ */
+static void lgr_stsi_1_1_1(struct lgr_info *lgr_info)
+{
+        struct sysinfo_1_1_1 *si = lgr_page;
+
+        if (stsi(si, 1, 1, 1) == -ENOSYS)
+                return;
+        cpascii(lgr_info->manufacturer, si->manufacturer,
+                sizeof(si->manufacturer));
+        cpascii(lgr_info->type, si->type, sizeof(si->type));
+        cpascii(lgr_info->model, si->model, sizeof(si->model));
+        cpascii(lgr_info->sequence, si->sequence, sizeof(si->sequence));
+        cpascii(lgr_info->plant, si->plant, sizeof(si->plant));
+}
+
+/*
+ * Fill LGR info with 2.2.2 stsi data
+ */
+static void lgr_stsi_2_2_2(struct lgr_info *lgr_info)
+{
+        struct sysinfo_2_2_2 *si = lgr_page;
+
+        if (stsi(si, 2, 2, 2) == -ENOSYS)
+                return;
+        cpascii(lgr_info->name, si->name, sizeof(si->name));
+        memcpy(&lgr_info->lpar_number, &si->lpar_number,
+               sizeof(lgr_info->lpar_number));
+}
+
+/*
+ * Fill LGR info with 3.2.2 stsi data
+ */
+static void lgr_stsi_3_2_2(struct lgr_info *lgr_info)
+{
+        struct sysinfo_3_2_2 *si = lgr_page;
+        int i;
+
+        if (stsi(si, 3, 2, 2) == -ENOSYS)
+                return;
+        for (i = 0; i < min_t(u8, si->count, VM_LEVEL_MAX); i++) {
+                cpascii(lgr_info->vm[i].name, si->vm[i].name,
+                        sizeof(si->vm[i].name));
+                cpascii(lgr_info->vm[i].cpi, si->vm[i].cpi,
+                        sizeof(si->vm[i].cpi));
+        }
+        lgr_info->vm_count = si->count;
+}
+
+/*
+ * Fill LGR info with current data
+ */
+static void lgr_info_get(struct lgr_info *lgr_info)
+{
+        memset(lgr_info, 0, sizeof(*lgr_info));
+        stfle(lgr_info->stfle_fac_list, ARRAY_SIZE(lgr_info->stfle_fac_list));
+        lgr_info->level = stsi_0();
+        if (lgr_info->level == -ENOSYS)
+                return;
+        if (lgr_info->level >= 1)
+                lgr_stsi_1_1_1(lgr_info);
+        if (lgr_info->level >= 2)
+                lgr_stsi_2_2_2(lgr_info);
+        if (lgr_info->level >= 3)
+                lgr_stsi_3_2_2(lgr_info);
+}
+
+/*
+ * Check if LGR info has changed and if yes log new LGR info to s390dbf
+ */
+void lgr_info_log(void)
+{
+        static DEFINE_SPINLOCK(lgr_info_lock);
+        unsigned long flags;
+
+        if (!spin_trylock_irqsave(&lgr_info_lock, flags))
+                return;
+        lgr_info_get(&lgr_info_cur);
+        if (memcmp(&lgr_info_last, &lgr_info_cur, sizeof(lgr_info_cur)) != 0) {
+                debug_event(lgr_dbf, 1, &lgr_info_cur, sizeof(lgr_info_cur));
+                lgr_info_last = lgr_info_cur;
+        }
+        spin_unlock_irqrestore(&lgr_info_lock, flags);
+}
+EXPORT_SYMBOL_GPL(lgr_info_log);
+
+static void lgr_timer_set(void);
+
+/*
+ * LGR timer callback
+ */
+static void lgr_timer_fn(unsigned long ignored)
+{
+        lgr_info_log();
+        lgr_timer_set();
+}
+
+static struct timer_list lgr_timer =
+        TIMER_DEFERRED_INITIALIZER(lgr_timer_fn, 0, 0);
+
+/*
+ * Setup next LGR timer
+ */
+static void lgr_timer_set(void)
+{
+        mod_timer(&lgr_timer, jiffies + LGR_TIMER_INTERVAL_SECS * HZ);
+}
+
+/*
+ * Initialize LGR: Add s390dbf, write initial lgr_info and setup timer
+ */
+static int __init lgr_init(void)
+{
+        lgr_page = (void *) __get_free_pages(GFP_KERNEL, 0);
+        if (!lgr_page)
+                return -ENOMEM;
+        lgr_dbf = debug_register("lgr", 1, 1, sizeof(struct lgr_info));
+        if (!lgr_dbf) {
+                free_page((unsigned long) lgr_page);
+                return -ENOMEM;
+        }
+        debug_register_view(lgr_dbf, &debug_hex_ascii_view);
+        lgr_info_get(&lgr_info_last);
+        debug_event(lgr_dbf, 1, &lgr_info_last, sizeof(lgr_info_last));
+        lgr_timer_set();
+        return 0;
+}
+module_init(lgr_init);
diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c
index bf6fbc03ebaf..0f8cdf1268d0 100644
--- a/arch/s390/kernel/machine_kexec.c
+++ b/arch/s390/kernel/machine_kexec.c
@@ -14,6 +14,7 @@
 #include <linux/delay.h>
 #include <linux/reboot.h>
 #include <linux/ftrace.h>
+#include <linux/debug_locks.h>
 #include <asm/cio.h>
 #include <asm/setup.h>
 #include <asm/pgtable.h>
@@ -209,10 +210,14 @@ static void __machine_kexec(void *data)
         struct kimage *image = data;
 
         pfault_fini();
-        if (image->type == KEXEC_TYPE_CRASH)
+        tracing_off();
+        debug_locks_off();
+        if (image->type == KEXEC_TYPE_CRASH) {
+                lgr_info_log();
                 s390_reset_system(__do_machine_kdump, data);
-        else
+        } else {
                 s390_reset_system(__do_machine_kexec, data);
+        }
         disabled_wait((unsigned long) __builtin_return_address(0));
 }
 
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 734e644972ab..d15b6c937088 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -40,6 +40,7 @@
 #include <asm/lowcore.h>
 #include <asm/sclp.h>
 #include <asm/vdso.h>
+#include <asm/debug.h>
 #include "entry.h"
 
 enum {
@@ -406,6 +407,7 @@ void smp_send_stop(void)
         __load_psw_mask(psw_kernel_bits | PSW_MASK_DAT);
         trace_hardirqs_off();
 
+        debug_set_critical();
         cpumask_copy(&cpumask, cpu_online_mask);
         cpumask_clear_cpu(smp_processor_id(), &cpumask);
 
diff --git a/arch/s390/kernel/swsusp_asm64.S b/arch/s390/kernel/swsusp_asm64.S
index ad3c79eceed7..dd70ef046058 100644
--- a/arch/s390/kernel/swsusp_asm64.S
+++ b/arch/s390/kernel/swsusp_asm64.S
@@ -257,6 +257,9 @@ restore_registers:
         lghi    %r2,0
         brasl   %r14,arch_set_page_states
 
+        /* Log potential guest relocation */
+        brasl   %r14,lgr_info_log
+
         /* Reinitialize the channel subsystem */
         brasl   %r14,channel_subsystem_reinit
 
diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c
index 5ce3750b181f..8894ac435d8d 100644
--- a/arch/s390/kernel/traps.c
+++ b/arch/s390/kernel/traps.c
@@ -41,6 +41,7 @@
 #include <asm/cpcmd.h>
 #include <asm/lowcore.h>
 #include <asm/debug.h>
+#include <asm/ipl.h>
 #include "entry.h"
 
 void (*pgm_check_table[128])(struct pt_regs *regs);
@@ -239,6 +240,7 @@ void die(struct pt_regs *regs, const char *str)
         static int die_counter;
 
         oops_enter();
+        lgr_info_log();
         debug_stop_all();
         console_verbose();
         spin_lock_irq(&die_lock);