Fix for Linux 3.11 and later ARM kernels, in which all non-panicking

cpus offline themselves during a kdump procedure. This causes an invalid cpu count determination during crash session initialization from an ARM vmcore. The patch utilizes the cpu count found in the cpu_active_map if it is greater than the count in the cpu_online_map. In addition, the maximum NR_CPUS value for the ARM architecture has been raised from 4 to 32. ([email protected])
linzhangru · Apr 28, 2014 · 8bff022 · 8bff022
1 parent a91e410
commit 8bff022
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Showing 9 changed files with 98 additions and 39 deletions.
diff --git a/arm.c b/arm.c
@@ -1518,7 +1518,7 @@ arm_display_machine_stats(void)
 static int
 arm_get_smp_cpus(void)
 {
-	return get_cpus_online();
+	return MAX(get_cpus_active(), get_cpus_online());
 }
 
 /*

diff --git a/defs.h b/defs.h
@@ -131,7 +131,7 @@
 #define NR_CPUS  (512)
 #endif
 #ifdef ARM
-#define NR_CPUS  (4)
+#define NR_CPUS  (32)
 #endif
 #ifdef ARM64
 #define NR_CPUS  (4096)   /* TBD */
@@ -658,6 +658,10 @@ struct kernel_table {                   /* kernel data */
 #define PRESENT   (0x2)
 #define ONLINE    (0x4)
 #define NMI       (0x8)
+#define POSSIBLE_MAP (POSSIBLE)
+#define PRESENT_MAP   (PRESENT)
+#define ONLINE_MAP     (ONLINE)
+#define ACTIVE_MAP       (0x10)
 	int BUG_bytes;
 	ulong xen_flags;
 #define WRITABLE_PAGE_TABLES    (0x1)
@@ -4795,6 +4799,7 @@ void set_cpu(int);
 void clear_machdep_cache(void);
 struct stack_hook *gather_text_list(struct bt_info *);
 int get_cpus_online(void);
+int get_cpus_active(void);
 int get_cpus_present(void);
 int get_cpus_possible(void);
 int get_highest_cpu_online(void);

diff --git a/diskdump.c b/diskdump.c
@@ -119,7 +119,7 @@ map_cpus_to_prstatus_kdump_cmprs(void)
 	nrcpus = (kt->kernel_NR_CPUS ? kt->kernel_NR_CPUS : NR_CPUS);
 
 	for (i = 0, j = 0; i < nrcpus; i++) {
-		if (in_cpu_map(ONLINE, i)) {
+		if (in_cpu_map(ONLINE_MAP, i)) {
 			dd->nt_prstatus_percpu[i] = nt_ptr[j++];
 			dd->num_prstatus_notes = 
 				MAX(dd->num_prstatus_notes, i+1);
@@ -1193,7 +1193,7 @@ get_diskdump_panic_task(void)
 		if (kernel_symbol_exists("crashing_cpu") &&
 		    cpu_map_addr("online")) {
 			get_symbol_data("crashing_cpu", sizeof(int), &i);
-			if ((i >= 0) && in_cpu_map(ONLINE, i)) {
+			if ((i >= 0) && in_cpu_map(ONLINE_MAP, i)) {
 				if (CRASHDEBUG(1))
 					error(INFO, "get_diskdump_panic_task: "
 					    "active_set[%d]: %lx\n", 

diff --git a/kernel.c b/kernel.c
@@ -795,9 +795,10 @@ cpu_maps_init(void)
 		ulong cpu_flag;
 		char *name;
 	} mapinfo[] = {
-		{ POSSIBLE, "possible" },
-		{ PRESENT, "present" },
-		{ ONLINE, "online" },
+		{ POSSIBLE_MAP, "possible" },
+		{ PRESENT_MAP, "present" },
+		{ ONLINE_MAP, "online" },
+		{ ACTIVE_MAP, "active" },
 	};
 
 	if ((len = STRUCT_SIZE("cpumask_t")) < 0)
@@ -864,26 +865,33 @@ in_cpu_map(int map, int cpu)
 
 	switch (map)
 	{
-	case POSSIBLE:
+	case POSSIBLE_MAP:
 		if (!cpu_map_addr("possible")) {
 			error(INFO, "cpu_possible_map does not exist\n");
 			return FALSE;
 		}
-		return (kt->cpu_flags[cpu] & POSSIBLE);
+		return (kt->cpu_flags[cpu] & POSSIBLE_MAP);
 
-	case PRESENT:
+	case PRESENT_MAP:
 		if (!cpu_map_addr("present")) {
 			error(INFO, "cpu_present_map does not exist\n");
 			return FALSE;
 		}
-		return (kt->cpu_flags[cpu] & PRESENT);
+		return (kt->cpu_flags[cpu] & PRESENT_MAP);
 
-	case ONLINE:
+	case ONLINE_MAP:
 		if (!cpu_map_addr("online")) {
 			error(INFO, "cpu_online_map does not exist\n");
 			return FALSE;
 		}
-		return (kt->cpu_flags[cpu] & ONLINE);
+		return (kt->cpu_flags[cpu] & ONLINE_MAP);
+
+	case ACTIVE_MAP:
+		if (!cpu_map_addr("active")) {
+			error(INFO, "cpu_active_map does not exist\n");
+			return FALSE;
+		}
+		return (kt->cpu_flags[cpu] & ACTIVE_MAP);
 	}
 
 	return FALSE;
@@ -5321,7 +5329,7 @@ dump_kernel_table(int verbose)
 	fprintf(fp, "       cpu_possible_map: ");
 	if (cpu_map_addr("possible")) {
 		for (i = 0; i < nr_cpus; i++) {
-			if (kt->cpu_flags[i] & POSSIBLE)
+			if (kt->cpu_flags[i] & POSSIBLE_MAP)
 				fprintf(fp, "%d ", i);
 		}
 		fprintf(fp, "\n");
@@ -5330,7 +5338,7 @@ dump_kernel_table(int verbose)
 	fprintf(fp, "        cpu_present_map: ");
 	if (cpu_map_addr("present")) {
 		for (i = 0; i < nr_cpus; i++) {
-			if (kt->cpu_flags[i] & PRESENT)
+			if (kt->cpu_flags[i] & PRESENT_MAP)
 				fprintf(fp, "%d ", i);
 		}
 		fprintf(fp, "\n");
@@ -5339,12 +5347,22 @@ dump_kernel_table(int verbose)
 	fprintf(fp, "         cpu_online_map: ");
 	if (cpu_map_addr("online")) {
 		for (i = 0; i < nr_cpus; i++) {
-			if (kt->cpu_flags[i] & ONLINE)
+			if (kt->cpu_flags[i] & ONLINE_MAP)
+				fprintf(fp, "%d ", i);
+		}
+		fprintf(fp, "\n");
+	} else
+		fprintf(fp, "(does not exist)\n");
+	fprintf(fp, "         cpu_active_map: ");
+	if (cpu_map_addr("active")) {
+		for (i = 0; i < nr_cpus; i++) {
+			if (kt->cpu_flags[i] & ACTIVE_MAP)
 				fprintf(fp, "%d ", i);
 		}
 		fprintf(fp, "\n");
 	} else
 		fprintf(fp, "(does not exist)\n");
+
 no_cpu_flags:
 	fprintf(fp, "    vmcoreinfo: \n");
 	fprintf(fp, "      log_buf_SYMBOL: %lx\n", kt->vmcoreinfo.log_buf_SYMBOL);
@@ -7972,6 +7990,40 @@ get_highest_cpu_online()
 	return highest;
 }
 
+/*
+ *  If it exists, return the number of cpus in the cpu_active_map.
+ */
+int
+get_cpus_active()
+{
+	int i, len, active;
+	char *buf;
+	ulong *maskptr, addr;
+
+	if (!(addr = cpu_map_addr("active")))
+		return 0;
+
+	len = cpu_map_size("active");
+	buf = GETBUF(len);
+
+	active = 0;
+
+	if (readmem(addr, KVADDR, buf, len,
+		"cpu_active_map", RETURN_ON_ERROR)) {
+
+		maskptr = (ulong *)buf;
+		for (i = 0; i < (len/sizeof(ulong)); i++, maskptr++)
+			active += count_bits_long(*maskptr);
+
+		if (CRASHDEBUG(1))
+			error(INFO, "get_cpus_active: active: %d\n", active);
+	}
+
+	FREEBUF(buf);
+
+	return active;
+}
+
 /*
  *  If it exists, return the number of cpus in the cpu_present_map.
  */

diff --git a/netdump.c b/netdump.c
@@ -92,7 +92,7 @@ map_cpus_to_prstatus(void)
 	nrcpus = (kt->kernel_NR_CPUS ? kt->kernel_NR_CPUS : NR_CPUS);
 
 	for (i = 0, j = 0; i < nrcpus; i++) {
-		if (in_cpu_map(ONLINE, i))
+		if (in_cpu_map(ONLINE_MAP, i))
 			nd->nt_prstatus_percpu[i] = nt_ptr[j++];
 	}
 
@@ -769,7 +769,7 @@ get_netdump_panic_task(void)
 		crashing_cpu = -1;
 		if (kernel_symbol_exists("crashing_cpu")) {
 			get_symbol_data("crashing_cpu", sizeof(int), &i);
-			if ((i >= 0) && in_cpu_map(ONLINE, i)) {
+			if ((i >= 0) && in_cpu_map(ONLINE_MAP, i)) {
 				crashing_cpu = i;
 				if (CRASHDEBUG(1))
 					error(INFO, 

diff --git a/ppc.c b/ppc.c
@@ -1,8 +1,8 @@
 /* ppc.c - core analysis suite
  *
  * Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc.
- * Copyright (C) 2002-2007, 2010-2013 David Anderson
- * Copyright (C) 2002-2007, 2010-2013 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2002-2007, 2010-2014 David Anderson
+ * Copyright (C) 2002-2007, 2010-2014 Red Hat, Inc. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -2036,7 +2036,7 @@ ppc_relocate_nt_prstatus_percpu(void **nt_prstatus_percpu,
 	*num_prstatus_notes = 0;
 	nrcpus = (kt->kernel_NR_CPUS ? kt->kernel_NR_CPUS : NR_CPUS);
 	for (i = 0, j = 0; i < nrcpus; i++) {
-		if (!in_cpu_map(ONLINE, i))
+		if (!in_cpu_map(ONLINE_MAP, i))
 			continue;
 		if (verify_crash_note_in_kernel(i))
 			nt_prstatus_percpu[i] = nt_ptr[j++];

diff --git a/ppc64.c b/ppc64.c
@@ -1,7 +1,7 @@
 /* ppc64.c -- core analysis suite
  *
- * Copyright (C) 2004-2013 David Anderson
- * Copyright (C) 2004-2013 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2004-2014 David Anderson
+ * Copyright (C) 2004-2014 Red Hat, Inc. All rights reserved.
  * Copyright (C) 2004, 2006 Haren Myneni, IBM Corporation
  *
  * This program is free software; you can redistribute it and/or modify
@@ -2861,16 +2861,18 @@ ppc64_get_cpu_map(void)
 	int map;
 
 	if (cpu_map_addr("possible"))
-		map = POSSIBLE;
+		map = POSSIBLE_MAP;
 	else if (cpu_map_addr("present"))
-		map = PRESENT;
+		map = PRESENT_MAP;
 	else if (cpu_map_addr("online"))
-		map = ONLINE;
+		map = ONLINE_MAP;
+	else if (cpu_map_addr("active"))
+		map = ACTIVE_MAP;
 	else {
 		map = 0;
 		error(FATAL,
-			"PPC64: cannot find 'cpu_possible_map' or\
-			'cpu_present_map' or 'cpu_online_map' symbols\n");
+			"PPC64: cannot find 'cpu_possible_map', "
+			"'cpu_present_map', 'cpu_online_map' or 'cpu_active_map' symbols\n");
 	}
 	return map;
 }
@@ -2911,15 +2913,15 @@ ppc64_init_cpu_info(void)
 	}
 	switch (map)
 	{
-	case POSSIBLE:
+	case POSSIBLE_MAP:
 		if (cpus > kt->cpus) {
 			i = get_highest_cpu_online() + 1;
 			if (i > kt->cpus)
 				kt->cpus = i;
 		}
 		break;
-	case ONLINE:
-	case PRESENT:
+	case ONLINE_MAP:
+	case PRESENT_MAP:
 		kt->cpus = cpus;
 		break;
 	}

diff --git a/s390.c b/s390.c
@@ -1,8 +1,8 @@
 /* s390.c - core analysis suite
  *
  * Copyright (C) 2001, 2002 Mission Critical Linux, Inc.
- * Copyright (C) 2002-2006, 2009-2010, 2012-2013 David Anderson
- * Copyright (C) 2002-2006, 2009-2010, 2012-2013 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2002-2006, 2009-2010, 2012-2014 David Anderson
+ * Copyright (C) 2002-2006, 2009-2010, 2012-2014 Red Hat, Inc. All rights reserved.
  * Copyright (C) 2005, 2006, 2010 Michael Holzheu, IBM Corporation
  *
  * This program is free software; you can redistribute it and/or modify
@@ -558,7 +558,7 @@ s390_has_cpu(struct bt_info *bt)
 {
 	int cpu = bt->tc->processor;
 
-	if (is_task_active(bt->task) && (kt->cpu_flags[cpu] & ONLINE))
+	if (is_task_active(bt->task) && (kt->cpu_flags[cpu] & ONLINE_MAP))
 		return TRUE;
 	else
 		return FALSE;
@@ -619,7 +619,7 @@ s390_back_trace_cmd(struct bt_info *bt)
 		error(WARNING,
 		"instruction pointer argument ignored on this architecture!\n");
 	}
-	if (is_task_active(bt->task) && !(kt->cpu_flags[cpu] & ONLINE)) {
+	if (is_task_active(bt->task) && !(kt->cpu_flags[cpu] & ONLINE_MAP)) {
 		fprintf(fp, " CPU offline\n");
 		return;
 	}

diff --git a/s390x.c b/s390x.c
@@ -1,8 +1,8 @@
 /* s390.c - core analysis suite
  *
  * Copyright (C) 2001, 2002 Mission Critical Linux, Inc.
- * Copyright (C) 2002-2006, 2009-2013 David Anderson
- * Copyright (C) 2002-2006, 2009-2013 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2002-2006, 2009-2014 David Anderson
+ * Copyright (C) 2002-2006, 2009-2014 Red Hat, Inc. All rights reserved.
  * Copyright (C) 2005, 2006, 2010-2013 Michael Holzheu, IBM Corporation
  *
  * This program is free software; you can redistribute it and/or modify
@@ -872,7 +872,7 @@ s390x_has_cpu(struct bt_info *bt)
 {
 	int cpu = bt->tc->processor;
 
-	if (is_task_active(bt->task) && (kt->cpu_flags[cpu] & ONLINE))
+	if (is_task_active(bt->task) && (kt->cpu_flags[cpu] & ONLINE_MAP))
 		return TRUE;
 	else
 		return FALSE;
@@ -1165,7 +1165,7 @@ static void s390x_back_trace_cmd(struct bt_info *bt)
 		error(WARNING,
 	        "instruction pointer argument ignored on this architecture!\n");
 	}
-	if (is_task_active(bt->task) && !(kt->cpu_flags[cpu] & ONLINE)) {
+	if (is_task_active(bt->task) && !(kt->cpu_flags[cpu] & ONLINE_MAP)) {
 		fprintf(fp, " CPU offline\n");
 		return;
 	}