[PATCH v2 7/8] makedumpfile: Add erased information in compressed kdump file

[PATCH v2 7/8] makedumpfile: Add erased information in compressed kdump file

[Mahesh J Salgaonkar]

From: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>

Include the erase information in the makedumpfile generated dumpfile. The
erased information contains only effective lines from the filter
configuration file. This patch supports inclusion of erase information in
kdump compressed, flatten and split dumpfiles. On re-filtering, the erase
information from input dumpfile (if any) will be carried over to resulting
dumpfile.

This patch introduces new members offset_eraseinfo, size_eraseinfo into the
sub header in compressed kdump file.

The erased information would contain *multiple* erased symbol names.
For example, the following is based on your above example.

	struct S1 {
		int a;
		int b;
		int c;
	};
	struct S2 {
		struct S1 *mystruct1;
		struct S1 *mystruct2;
	};

	struct S2 mystruct2;

	#Filter command
	erase mystruct2.mystruct1.a
	erase mystruct2.mystruct1.c
	erase mystruct2.mystruct2.b

	#The erased information
	erase mystruct2.mystruct1.a 4
	erase mystruct2.mystruct1.c 4
	erase mystruct2.mystruct2.b 4

The dumpfile image :

       header             dump data             the erased information
+------------------+-----------------------+-------------------------------+
| ................ | ..................... | erase mystruct2.mystruct1.a 4 |
| offset_eraseinfo | ..................... | erase mystruct2.mystruct1.c 4 |
|   size_eraseinfo | ..................... | erase mystruct2.mystruct2.b 4 |
+------------------+-------------------------------------------------------+
                                           : offset_eraseinfo (offset in
                                             dumpfile)
                                            <------ size_eraseinfo ------->

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
---

 IMPLEMENTATION |    6 +
 diskdump_mod.h |    2 
 makedumpfile.c |  359 ++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 makedumpfile.h |   30 +++++
 4 files changed, 387 insertions(+), 10 deletions(-)

diff --git a/IMPLEMENTATION b/IMPLEMENTATION
index 9aea0d4..c11bd36 100644
--- a/IMPLEMENTATION
+++ b/IMPLEMENTATION
@@ -25,6 +25,10 @@
     |         page data (pfn 1)                |
     |                        :                 |
     |         page data (pfn Z)                |
+    +------------------------------------------+ offset_eraseinfo
+    | erase mystruct2.mystruct1.var 4          |
+    | erase mystruct2.mystruct1.ptr nullify    |
+    | erase mystruct2.mystruct.array 100       |
     +------------------------------------------+
 
 
@@ -71,6 +75,8 @@
 	unsigned long	size_vmcoreinfo;  /* header_version 3 and later */
 	off_t		offset_note;      /* header_version 4 and later */
 	unsigned long	size_note;        /* header_version 4 and later */
+	off_t		offset_eraseinfo; /* header_version 5 and later */
+	unsigned long	size_eraseinfo;   /* header_version 5 and later */
     };
 
   - 1st-bitmap
diff --git a/diskdump_mod.h b/diskdump_mod.h
index bab991c..2022770 100644
--- a/diskdump_mod.h
+++ b/diskdump_mod.h
@@ -75,6 +75,8 @@ struct kdump_sub_header {
 	unsigned long	size_vmcoreinfo;  /* header_version 3 and later */
 	off_t		offset_note;      /* header_version 4 and later */
 	unsigned long	size_note;        /* header_version 4 and later */
+	off_t		offset_eraseinfo; /* header_version 5 and later */
+	unsigned long	size_eraseinfo;   /* header_version 5 and later */
 };
 
 /* page flags */
diff --git a/makedumpfile.c b/makedumpfile.c
index a616bae..b5ad5f7 100644
--- a/makedumpfile.c
+++ b/makedumpfile.c
@@ -29,6 +29,8 @@ struct DumpInfo		*info = NULL;
 struct module_sym_table	mod_st = { 0 };
 struct filter_info	*filter_info = NULL;
 struct filter_config	filter_config;
+struct erase_info	*erase_info = NULL;
+unsigned long		num_erase_info = 1; /* Node 0 is unused. */
 
 char filename_stdout[] = FILENAME_STDOUT;
 int message_level;
@@ -951,6 +953,11 @@ get_kdump_compressed_header_info(char *filename)
 		info->offset_note = kh.offset_note;
 		info->size_note   = kh.size_note;
 	}
+	if (dh.header_version >= 5) {
+		/* A dumpfile contains erased information. */
+		info->offset_eraseinfo = kh.offset_eraseinfo;
+		info->size_eraseinfo   = kh.size_eraseinfo;
+	}
 	return TRUE;
 error:
 	free(info->dh_memory);
@@ -5932,7 +5939,7 @@ write_kdump_header(void)
 	 * Write common header
 	 */
 	strncpy(dh->signature, KDUMP_SIGNATURE, strlen(KDUMP_SIGNATURE));
-	dh->header_version = 4;
+	dh->header_version = 5;
   	dh->block_size     = info->page_size;
 	dh->sub_hdr_size   = sizeof(kh) + info->size_note;
 	dh->sub_hdr_size   = divideup(dh->sub_hdr_size, dh->block_size);
@@ -6000,10 +6007,17 @@ write_kdump_header(void)
 			kh.size_vmcoreinfo = info->size_vmcoreinfo;
 		}
 	}
-	if (!write_buffer(info->fd_dumpfile, dh->block_size, &kh,
-	    size, info->name_dumpfile))
-		goto out;
+	/*
+	 * While writing dump data to STDOUT, delay the writing of sub header
+	 * untill we gather erase info offset and size.
+	 */
+	if (!info->flag_flatten) {
+		if (!write_buffer(info->fd_dumpfile, dh->block_size, &kh,
+		    size, info->name_dumpfile))
+			goto out;
+	}
 
+	info->sub_header = kh;
 	info->offset_bitmap1
 	    = (DISKDUMP_HEADER_BLOCKS + dh->sub_hdr_size) * dh->block_size;
 
@@ -6061,12 +6075,39 @@ split_filter_info(struct filter_info *prev, unsigned long long next_paddr,
 		return;
 	}
 	new->nullify = prev->nullify;
+	new->erase_info_idx = prev->erase_info_idx;
+	new->size_idx = prev->size_idx;
 	new->paddr = next_paddr;
 	new->size = size;
 	new->next = prev->next;
 	prev->next = new;
 }
 
+void
+update_erase_info(struct filter_info *fi)
+{
+	struct erase_info *ei;
+
+	if (!fi->erase_info_idx)
+		return;
+
+	ei = &erase_info[fi->erase_info_idx];
+
+	if (!ei->sizes) {
+		/* First time, allocate sizes array */
+		ei->sizes = calloc(ei->num_sizes, sizeof(long));
+		if (!ei->sizes) {
+			ERRMSG("Can't allocate memory for erase info sizes\n");
+			return;
+		}
+	}
+	ei->erased = 1;
+	if (!fi->nullify)
+		ei->sizes[fi->size_idx] += fi->size;
+	else
+		ei->sizes[fi->size_idx] = -1;
+}
+
 int
 extract_filter_info(unsigned long long start_paddr,
 			unsigned long long end_paddr,
@@ -6100,6 +6141,7 @@ extract_filter_info(unsigned long long start_paddr,
 			filter_info = fi->next;
 		else
 			prev->next = fi->next;
+		update_erase_info(fi);
 		free(fi);
 		return TRUE;
 	}
@@ -6567,6 +6609,159 @@ out:
 	return ret;
 }
 
+/*
+ * Copy eraseinfo from input dumpfile/vmcore to output dumpfile.
+ */
+static int
+copy_eraseinfo(struct cache_data *cd_eraseinfo)
+{
+	char *buf = NULL;
+	int ret = FALSE;
+
+	buf = malloc(info->size_eraseinfo);
+	if (buf == NULL) {
+		ERRMSG("Can't allocate memory for erase info section. %s\n",
+		    strerror(errno));
+		return FALSE;
+	}
+	if (lseek(info->fd_memory, info->offset_eraseinfo, SEEK_SET) < 0) {
+		ERRMSG("Can't seek the dump memory(%s). %s\n",
+		    info->name_memory, strerror(errno));
+		goto out;
+	}
+	if (read(info->fd_memory, buf, info->size_eraseinfo)
+	    != info->size_eraseinfo) {
+		ERRMSG("Can't read the dump memory(%s). %s\n",
+		    info->name_memory, strerror(errno));
+		goto out;
+	}
+	if (!write_cache(cd_eraseinfo, buf, info->size_eraseinfo))
+		goto out;
+	ret = TRUE;
+out:
+	if (buf)
+		free(buf);
+	return ret;
+}
+
+static int
+update_sub_header(void)
+{
+	off_t offset;
+
+	/* seek to kdump sub header offset */
+	offset = DISKDUMP_HEADER_BLOCKS * info->page_size;
+
+	info->sub_header.offset_eraseinfo = info->offset_eraseinfo;
+	info->sub_header.size_eraseinfo = info->size_eraseinfo;
+
+	if (!write_buffer(info->fd_dumpfile, offset, &info->sub_header,
+			sizeof(struct kdump_sub_header), info->name_dumpfile))
+		return FALSE;
+
+	return TRUE;
+}
+
+/*
+ * Traverse through eraseinfo nodes and write it to the o/p dumpfile if the
+ * node has erased flag set.
+ */
+int
+write_eraseinfo(struct cache_data *cd_page, unsigned long *size_out)
+{
+	int i, j, obuf_size = 0, ei_size = 0;
+	int ret = FALSE;
+	unsigned long size_eraseinfo = 0;
+	char *obuf = NULL;
+	char size_str[MAX_SIZE_STR_LEN];
+
+	for (i = 1; i < num_erase_info; i++) {
+		if (!erase_info[i].erased)
+			continue;
+		for (j = 0; j < erase_info[i].num_sizes; j++) {
+			if (erase_info[i].sizes[j] > 0)
+				sprintf(size_str, "%ld\n",
+						erase_info[i].sizes[j]);
+			else if (erase_info[i].sizes[j] == -1)
+				sprintf(size_str, "nullify\n");
+
+			/* Calculate the required buffer size. */
+			ei_size = strlen("erase ") +
+					strlen(erase_info[i].symbol_expr) + 1 +
+					strlen(size_str) +
+					1;
+			/*
+			 * If obuf is allocated in the previous run and is
+			 * big enough to hold current erase info string then
+			 * reuse it otherwise realloc.
+			 */
+			if (ei_size > obuf_size) {
+				obuf_size = ei_size;
+				obuf = realloc(obuf, obuf_size);
+				if (!obuf) {
+					ERRMSG("Can't allocate memory for"
+						" output buffer\n");
+					return FALSE;
+				}
+			}
+			sprintf(obuf, "erase %s %s", erase_info[i].symbol_expr,
+							size_str);
+			DEBUG_MSG(obuf);
+			if (!write_cache(cd_page, obuf, strlen(obuf)))
+				goto out;
+			size_eraseinfo += strlen(obuf);
+		}
+	}
+	/*
+	 * Write the remainder.
+	 */
+	if (!write_cache_bufsz(cd_page))
+		goto out;
+
+	*size_out = size_eraseinfo;
+	ret = TRUE;
+out:
+	if (obuf)
+		free(obuf);
+
+	return ret;
+}
+
+int
+write_kdump_eraseinfo(struct cache_data *cd_page)
+{
+	off_t offset_eraseinfo;
+	unsigned long size_eraseinfo;
+
+	DEBUG_MSG("Writing erase info...\n");
+	offset_eraseinfo = cd_page->offset;
+
+	/*
+	 * In case of refiltering copy the existing eraseinfo from input
+	 * dumpfile to o/p dumpfile.
+	 */
+	if (info->offset_eraseinfo && info->size_eraseinfo) {
+		if (!copy_eraseinfo(cd_page))
+			return FALSE;
+	}
+
+	/* Initialize eraseinfo offset with new offset value. */
+	info->offset_eraseinfo = offset_eraseinfo;
+
+	if (!write_eraseinfo(cd_page, &size_eraseinfo))
+		return FALSE;
+
+	info->size_eraseinfo += size_eraseinfo;
+	DEBUG_MSG("offset_eraseinfo: %lx, size_eraseinfo: %ld\n",
+			info->offset_eraseinfo, info->size_eraseinfo);
+
+	/* Update the erase info offset and size in kdump sub header */
+	if (!update_sub_header())
+		return FALSE;
+
+	return TRUE;
+}
+
 int
 write_kdump_bitmap(void)
 {
@@ -7391,6 +7586,8 @@ writeout_dumpfile(void)
 			goto out;
 		if (!write_kdump_pages(&cd_header, &cd_page))
 			goto out;
+		if (!write_kdump_eraseinfo(&cd_page))
+			goto out;
 		if (!write_kdump_bitmap())
 			goto out;
 	}
@@ -7781,6 +7978,8 @@ free_config_entry(struct config_entry *ce)
 			free(p->name);
 		if (p->type_name)
 			free(p->type_name);
+		if (p->symbol_expr)
+			free(p->symbol_expr);
 		free(p);
 	}
 }
@@ -8129,6 +8328,13 @@ read_filter_entry(struct config *config, int line)
 									line);
 		return FALSE;
 	}
+
+	/*
+	 * Save the symbol expression string for generation of eraseinfo data
+	 * later while writing dumpfile.
+	 */
+	config->filter_symbol[idx]->symbol_expr = strdup(token);
+
 	if (config->iter_entry) {
 		if (strcmp(config->filter_symbol[idx]->name,
 				config->iter_entry->name)) {
@@ -8726,8 +8932,11 @@ resolve_list_entry(struct config_entry *ce, unsigned long long base_addr,
  * Insert the filter info node using insertion sort.
  * If filter node for a given paddr is aready present then update the size
  * and delete the fl_info node passed.
+ *
+ * Return 1 on successfull insertion.
+ * Return 0 if filter node with same paddr is found.
  */
-void
+int
 insert_filter_info(struct filter_info *fl_info)
 {
 	struct filter_info *prev = NULL;
@@ -8735,7 +8944,7 @@ insert_filter_info(struct filter_info *fl_info)
 
 	if (!ptr) {
 		filter_info = fl_info;
-		return;
+		return 1;
 	}
 
 	while (ptr) {
@@ -8748,7 +8957,7 @@ insert_filter_info(struct filter_info *fl_info)
 		if (fl_info->size > ptr->size)
 			ptr->size = fl_info->size;
 		free(fl_info);
-		return;
+		return 0;
 	}
 
 	if (prev) {
@@ -8759,7 +8968,80 @@ insert_filter_info(struct filter_info *fl_info)
 		fl_info->next = filter_info;
 		filter_info = fl_info;
 	}
-	return;
+	return 1;
+}
+
+/*
+ * Create an erase info node for each erase command. One node per erase
+ * command even if it is part of loop construct.
+ * For erase commands that are not part of loop construct, the num_sizes will
+ * always be 1
+ * For erase commands that are part of loop construct, the num_sizes may be
+ * 1 or >1 depending on number iterations. This function will called multiple
+ * times depending on iterations. At first invokation create a node and
+ * increment num_sizes for subsequent invokations.
+ *
+ * The valid erase info node starts from index value 1. (index 0 is invalid
+ * index).
+ *
+ *            Index 0     1        2        3
+ *             +------+--------+--------+--------+
+ * erase_info->|Unused|        |        |        |......
+ *             +------+--------+--------+--------+
+ *                        |        .        .        .....
+ *                        V
+ *                   +---------+
+ *                   | char*   |----> Original erase command string
+ *                   +---------+
+ *                   |num_sizes|
+ *                   +---------+      +--+--+--+
+ *                   | sizes   |----> |  |  |  |... Sizes array of num_sizes
+ *                   +---------+      +--+--+--+
+ *
+ * On success, return the index value of erase node for given erase command.
+ * On failure, return 0.
+ */
+static int
+add_erase_info_node(struct config_entry *filter_symbol)
+{
+	int idx = filter_symbol->erase_info_idx;
+
+	/*
+	 * Check if node is already created, if yes, increment the num_sizes.
+	 */
+	if (idx) {
+		erase_info[idx].num_sizes++;
+		return idx;
+	}
+
+	/* Allocate a new node. */
+	DEBUG_MSG("Allocating new erase info node for command \"%s\"\n",
+			filter_symbol->symbol_expr);
+	idx = num_erase_info++;
+	erase_info = realloc(erase_info,
+			sizeof(struct erase_info) * num_erase_info);
+	if (!erase_info) {
+		ERRMSG("Can't get memory to create erase information.\n");
+		return 0;
+	}
+
+	memset(&erase_info[idx], 0, sizeof(struct erase_info));
+	erase_info[idx].symbol_expr = filter_symbol->symbol_expr;
+	erase_info[idx].num_sizes = 1;
+
+	filter_symbol->symbol_expr = NULL;
+	filter_symbol->erase_info_idx = idx;
+
+	return idx;
+}
+
+/* Return the index value in sizes array for given erase command index. */
+static inline int
+get_size_index(int ei_idx)
+{
+	if (ei_idx)
+		return erase_info[ei_idx].num_sizes - 1;
+	return 0;
 }
 
 int
@@ -8798,7 +9080,10 @@ update_filter_info(struct config_entry *filter_symbol,
 	fl_info->size = size;
 	fl_info->nullify = filter_symbol->nullify;
 
-	insert_filter_info(fl_info);
+	if (insert_filter_info(fl_info)) {
+		fl_info->erase_info_idx = add_erase_info_node(filter_symbol);
+		fl_info->size_idx = get_size_index(fl_info->erase_info_idx);
+	}
 	return TRUE;
 }
 
@@ -9049,6 +9334,7 @@ void
 clear_filter_info(void)
 {
 	struct filter_info *prev, *fi = filter_info;
+	int i;
 
 	/* Delete filter_info nodes that are left out. */
 	while (fi) {
@@ -9057,6 +9343,13 @@ clear_filter_info(void)
 		free(prev);
 	}
 	filter_info = NULL;
+	if (erase_info) {
+		for (i = 1; i < num_erase_info; i++) {
+			free(erase_info[i].symbol_expr);
+			free(erase_info[i].sizes);
+		}
+		free(erase_info);
+	}
 }
 
 int
@@ -9245,6 +9538,8 @@ store_splitting_info(void)
 		}
 		SPLITTING_START_PFN(i) = kh.start_pfn;
 		SPLITTING_END_PFN(i)   = kh.end_pfn;
+		SPLITTING_OFFSET_EI(i) = kh.offset_eraseinfo;
+		SPLITTING_SIZE_EI(i)   = kh.size_eraseinfo;
 	}
 	return TRUE;
 }
@@ -9452,6 +9747,7 @@ reassemble_kdump_pages(void)
 	struct cache_data cd_pd, cd_data;
 	struct timeval tv_start;
 	char *data = NULL;
+	unsigned long data_buf_size = info->page_size;
 
 	initialize_2nd_bitmap(&bitmap2);
 
@@ -9465,7 +9761,7 @@ reassemble_kdump_pages(void)
 		free_cache_data(&cd_pd);
 		return FALSE;
 	}
-	if ((data = malloc(info->page_size)) == NULL) {
+	if ((data = malloc(data_buf_size)) == NULL) {
 		ERRMSG("Can't allcate memory for page data.\n");
 		free_cache_data(&cd_pd);
 		free_cache_data(&cd_data);
@@ -9570,6 +9866,49 @@ reassemble_kdump_pages(void)
 	if (!write_cache_bufsz(&cd_data))
 		goto out;
 
+	info->offset_eraseinfo = cd_data.offset;
+	/* Copy eraseinfo from split dumpfiles to o/p dumpfile */
+	for (i = 0; i < info->num_dumpfile; i++) {
+		if (!SPLITTING_SIZE_EI(i))
+			continue;
+
+		if (SPLITTING_SIZE_EI(i) > data_buf_size) {
+			data_buf_size = SPLITTING_SIZE_EI(i);
+			if ((data = realloc(data, data_buf_size)) == NULL) {
+				ERRMSG("Can't allcate memory for eraseinfo"
+					" data.\n");
+				goto out;
+			}
+		}
+		if ((fd = open(SPLITTING_DUMPFILE(i), O_RDONLY)) < 0) {
+			ERRMSG("Can't open a file(%s). %s\n",
+			    SPLITTING_DUMPFILE(i), strerror(errno));
+			goto out;
+		}
+		if (lseek(fd, SPLITTING_OFFSET_EI(i), SEEK_SET) < 0) {
+			ERRMSG("Can't seek a file(%s). %s\n",
+			    SPLITTING_DUMPFILE(i), strerror(errno));
+			goto out;
+		}
+		if (read(fd, data, SPLITTING_SIZE_EI(i)) !=
+						SPLITTING_SIZE_EI(i)) {
+			ERRMSG("Can't read a file(%s). %s\n",
+			    SPLITTING_DUMPFILE(i), strerror(errno));
+			goto out;
+		}
+		if (!write_cache(&cd_data, data, SPLITTING_SIZE_EI(i)))
+			goto out;
+		info->size_eraseinfo += SPLITTING_SIZE_EI(i);
+
+		close(fd);
+		fd = 0;
+	}
+	if (!write_cache_bufsz(&cd_data))
+		goto out;
+
+	if (!update_sub_header())
+		goto out;
+
 	print_progress(PROGRESS_COPY, num_dumpable, num_dumpable);
 	print_execution_time(PROGRESS_COPY, &tv_start);
 
diff --git a/makedumpfile.h b/makedumpfile.h
index 1c61edb..2e4b902 100644
--- a/makedumpfile.h
+++ b/makedumpfile.h
@@ -434,6 +434,8 @@ do { \
 #define SPLITTING_FD_BITMAP(i)	info->splitting_info[i].fd_bitmap
 #define SPLITTING_START_PFN(i)	info->splitting_info[i].start_pfn
 #define SPLITTING_END_PFN(i)	info->splitting_info[i].end_pfn
+#define SPLITTING_OFFSET_EI(i)	info->splitting_info[i].offset_eraseinfo
+#define SPLITTING_SIZE_EI(i)	info->splitting_info[i].size_eraseinfo
 
 /*
  * kernel version
@@ -499,6 +501,8 @@ do { \
 #define XEN_ELFNOTE_CRASH_INFO	(0x1000001)
 #define SIZE_XEN_CRASH_INFO_V2	(sizeof(unsigned long) * 10)
 
+#define MAX_SIZE_STR_LEN (21)
+
 /*
  * The value of dependence on machine
  */
@@ -841,6 +845,8 @@ struct splitting_info {
 	int 			fd_bitmap;
 	unsigned long long	start_pfn;
 	unsigned long long	end_pfn;
+	off_t			offset_eraseinfo;
+	unsigned long		size_eraseinfo;
 } splitting_info_t;
 
 struct DumpInfo {
@@ -905,6 +911,7 @@ struct DumpInfo {
 	struct dump_bitmap 		*bitmap1;
 	struct dump_bitmap 		*bitmap2;
 	struct disk_dump_header		*dump_header;
+	struct kdump_sub_header		sub_header;
 
 	/*
 	 * ELF header info:
@@ -973,6 +980,12 @@ struct DumpInfo {
 	unsigned long		size_note;
 
 	/*
+	 * erased information in dump memory image info:
+	 */
+	off_t			offset_eraseinfo;
+	unsigned long		size_eraseinfo;
+
+	/*
 	 * for Xen extraction
 	 */
 	off_t			offset_xen_crash_info;
@@ -1280,12 +1293,27 @@ struct dwarf_info {
 extern struct dwarf_info	dwarf_info;
 
 /*
+ * Erase information, original symbol expressions.
+ */
+struct erase_info {
+	char		*symbol_expr;
+	int		num_sizes;
+	long		*sizes;
+	int		erased;		/* 1= erased, 0= Not erased */
+};
+
+/*
  * Filtering information
  */
 struct filter_info {
 	unsigned long long      address;
 	unsigned long long      paddr;
 	long			size;
+
+	/* direct access to update erase information node */
+	int			erase_info_idx;	/* 0= invalid index */
+	int			size_idx;
+
 	struct filter_info      *next;
 	unsigned short          nullify;
 };
@@ -1293,6 +1321,7 @@ struct filter_info {
 struct config_entry {
 	char			*name;
 	char			*type_name;
+	char			*symbol_expr;	/* original symbol expression */
 	unsigned short		flag;
 	unsigned short		nullify;
 	unsigned long long	sym_addr;	/* Symbol address */
@@ -1305,6 +1334,7 @@ struct config_entry {
 	long			index;
 	long			size;
 	int			line;	/* Line number in config file. */
+	int			erase_info_idx;	/* 0= invalid index */
 	struct config_entry	*refer_to;
 	struct config_entry	*next;
 };


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Re: [PATCH v2 7/8] makedumpfile: Add erased information in compressed kdump file

[Ken'ichi Ohmichi]

Hi Mahesh,

On Wed, 18 May 2011 01:36:17 +0530
Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> wrote:
> --- a/makedumpfile.c
> +++ b/makedumpfile.c
> @@ -29,6 +29,8 @@ struct DumpInfo		*info = NULL;
>  struct module_sym_table	mod_st = { 0 };
>  struct filter_info	*filter_info = NULL;
>  struct filter_config	filter_config;
> +struct erase_info	*erase_info = NULL;
> +unsigned long		num_erase_info = 1; /* Node 0 is unused. */

I cannot understand erase_info[0] is unused.


> @@ -6000,10 +6007,17 @@ write_kdump_header(void)
>  			kh.size_vmcoreinfo = info->size_vmcoreinfo;
>  		}
>  	}
> -	if (!write_buffer(info->fd_dumpfile, dh->block_size, &kh,
> -	    size, info->name_dumpfile))
> -		goto out;
> +	/*
> +	 * While writing dump data to STDOUT, delay the writing of sub header
> +	 * untill we gather erase info offset and size.
> +	 */
> +	if (!info->flag_flatten) {
> +		if (!write_buffer(info->fd_dumpfile, dh->block_size, &kh,
> +		    size, info->name_dumpfile))
> +			goto out;
> +	}

Does makedumpfile work wrong if removing the above change ?


I'd like to check this patch carefully, and I will review the remainder
next week.


Thanks
Ken'ichi Ohmichi


> @@ -6061,12 +6075,39 @@ split_filter_info(struct filter_info *prev, unsigned long long next_paddr,
>  		return;
>  	}
>  	new->nullify = prev->nullify;
> +	new->erase_info_idx = prev->erase_info_idx;
> +	new->size_idx = prev->size_idx;
>  	new->paddr = next_paddr;
>  	new->size = size;
>  	new->next = prev->next;
>  	prev->next = new;
>  }
>  
> +void
> +update_erase_info(struct filter_info *fi)
> +{
> +	struct erase_info *ei;
> +
> +	if (!fi->erase_info_idx)
> +		return;
> +
> +	ei = &erase_info[fi->erase_info_idx];
> +
> +	if (!ei->sizes) {
> +		/* First time, allocate sizes array */
> +		ei->sizes = calloc(ei->num_sizes, sizeof(long));
> +		if (!ei->sizes) {
> +			ERRMSG("Can't allocate memory for erase info sizes\n");
> +			return;
> +		}
> +	}
> +	ei->erased = 1;
> +	if (!fi->nullify)
> +		ei->sizes[fi->size_idx] += fi->size;
> +	else
> +		ei->sizes[fi->size_idx] = -1;
> +}
> +
>  int
>  extract_filter_info(unsigned long long start_paddr,
>  			unsigned long long end_paddr,
> @@ -6100,6 +6141,7 @@ extract_filter_info(unsigned long long start_paddr,
>  			filter_info = fi->next;
>  		else
>  			prev->next = fi->next;
> +		update_erase_info(fi);
>  		free(fi);
>  		return TRUE;
>  	}
> @@ -6567,6 +6609,159 @@ out:
>  	return ret;
>  }
>  
> +/*
> + * Copy eraseinfo from input dumpfile/vmcore to output dumpfile.
> + */
> +static int
> +copy_eraseinfo(struct cache_data *cd_eraseinfo)
> +{
> +	char *buf = NULL;
> +	int ret = FALSE;
> +
> +	buf = malloc(info->size_eraseinfo);
> +	if (buf == NULL) {
> +		ERRMSG("Can't allocate memory for erase info section. %s\n",
> +		    strerror(errno));
> +		return FALSE;
> +	}
> +	if (lseek(info->fd_memory, info->offset_eraseinfo, SEEK_SET) < 0) {
> +		ERRMSG("Can't seek the dump memory(%s). %s\n",
> +		    info->name_memory, strerror(errno));
> +		goto out;
> +	}
> +	if (read(info->fd_memory, buf, info->size_eraseinfo)
> +	    != info->size_eraseinfo) {
> +		ERRMSG("Can't read the dump memory(%s). %s\n",
> +		    info->name_memory, strerror(errno));
> +		goto out;
> +	}
> +	if (!write_cache(cd_eraseinfo, buf, info->size_eraseinfo))
> +		goto out;
> +	ret = TRUE;
> +out:
> +	if (buf)
> +		free(buf);
> +	return ret;
> +}
> +
> +static int
> +update_sub_header(void)
> +{
> +	off_t offset;
> +
> +	/* seek to kdump sub header offset */
> +	offset = DISKDUMP_HEADER_BLOCKS * info->page_size;
> +
> +	info->sub_header.offset_eraseinfo = info->offset_eraseinfo;
> +	info->sub_header.size_eraseinfo = info->size_eraseinfo;
> +
> +	if (!write_buffer(info->fd_dumpfile, offset, &info->sub_header,
> +			sizeof(struct kdump_sub_header), info->name_dumpfile))
> +		return FALSE;
> +
> +	return TRUE;
> +}
> +
> +/*
> + * Traverse through eraseinfo nodes and write it to the o/p dumpfile if the
> + * node has erased flag set.
> + */
> +int
> +write_eraseinfo(struct cache_data *cd_page, unsigned long *size_out)
> +{
> +	int i, j, obuf_size = 0, ei_size = 0;
> +	int ret = FALSE;
> +	unsigned long size_eraseinfo = 0;
> +	char *obuf = NULL;
> +	char size_str[MAX_SIZE_STR_LEN];
> +
> +	for (i = 1; i < num_erase_info; i++) {
> +		if (!erase_info[i].erased)
> +			continue;
> +		for (j = 0; j < erase_info[i].num_sizes; j++) {
> +			if (erase_info[i].sizes[j] > 0)
> +				sprintf(size_str, "%ld\n",
> +						erase_info[i].sizes[j]);
> +			else if (erase_info[i].sizes[j] == -1)
> +				sprintf(size_str, "nullify\n");
> +
> +			/* Calculate the required buffer size. */
> +			ei_size = strlen("erase ") +
> +					strlen(erase_info[i].symbol_expr) + 1 +
> +					strlen(size_str) +
> +					1;
> +			/*
> +			 * If obuf is allocated in the previous run and is
> +			 * big enough to hold current erase info string then
> +			 * reuse it otherwise realloc.
> +			 */
> +			if (ei_size > obuf_size) {
> +				obuf_size = ei_size;
> +				obuf = realloc(obuf, obuf_size);
> +				if (!obuf) {
> +					ERRMSG("Can't allocate memory for"
> +						" output buffer\n");
> +					return FALSE;
> +				}
> +			}
> +			sprintf(obuf, "erase %s %s", erase_info[i].symbol_expr,
> +							size_str);
> +			DEBUG_MSG(obuf);
> +			if (!write_cache(cd_page, obuf, strlen(obuf)))
> +				goto out;
> +			size_eraseinfo += strlen(obuf);
> +		}
> +	}
> +	/*
> +	 * Write the remainder.
> +	 */
> +	if (!write_cache_bufsz(cd_page))
> +		goto out;
> +
> +	*size_out = size_eraseinfo;
> +	ret = TRUE;
> +out:
> +	if (obuf)
> +		free(obuf);
> +
> +	return ret;
> +}
> +
> +int
> +write_kdump_eraseinfo(struct cache_data *cd_page)
> +{
> +	off_t offset_eraseinfo;
> +	unsigned long size_eraseinfo;
> +
> +	DEBUG_MSG("Writing erase info...\n");
> +	offset_eraseinfo = cd_page->offset;
> +
> +	/*
> +	 * In case of refiltering copy the existing eraseinfo from input
> +	 * dumpfile to o/p dumpfile.
> +	 */
> +	if (info->offset_eraseinfo && info->size_eraseinfo) {
> +		if (!copy_eraseinfo(cd_page))
> +			return FALSE;
> +	}
> +
> +	/* Initialize eraseinfo offset with new offset value. */
> +	info->offset_eraseinfo = offset_eraseinfo;
> +
> +	if (!write_eraseinfo(cd_page, &size_eraseinfo))
> +		return FALSE;
> +
> +	info->size_eraseinfo += size_eraseinfo;
> +	DEBUG_MSG("offset_eraseinfo: %lx, size_eraseinfo: %ld\n",
> +			info->offset_eraseinfo, info->size_eraseinfo);
> +
> +	/* Update the erase info offset and size in kdump sub header */
> +	if (!update_sub_header())
> +		return FALSE;
> +
> +	return TRUE;
> +}
> +
>  int
>  write_kdump_bitmap(void)
>  {
> @@ -7391,6 +7586,8 @@ writeout_dumpfile(void)
>  			goto out;
>  		if (!write_kdump_pages(&cd_header, &cd_page))
>  			goto out;
> +		if (!write_kdump_eraseinfo(&cd_page))
> +			goto out;
>  		if (!write_kdump_bitmap())
>  			goto out;
>  	}
> @@ -7781,6 +7978,8 @@ free_config_entry(struct config_entry *ce)
>  			free(p->name);
>  		if (p->type_name)
>  			free(p->type_name);
> +		if (p->symbol_expr)
> +			free(p->symbol_expr);
>  		free(p);
>  	}
>  }
> @@ -8129,6 +8328,13 @@ read_filter_entry(struct config *config, int line)
>  									line);
>  		return FALSE;
>  	}
> +
> +	/*
> +	 * Save the symbol expression string for generation of eraseinfo data
> +	 * later while writing dumpfile.
> +	 */
> +	config->filter_symbol[idx]->symbol_expr = strdup(token);
> +
>  	if (config->iter_entry) {
>  		if (strcmp(config->filter_symbol[idx]->name,
>  				config->iter_entry->name)) {
> @@ -8726,8 +8932,11 @@ resolve_list_entry(struct config_entry *ce, unsigned long long base_addr,
>   * Insert the filter info node using insertion sort.
>   * If filter node for a given paddr is aready present then update the size
>   * and delete the fl_info node passed.
> + *
> + * Return 1 on successfull insertion.
> + * Return 0 if filter node with same paddr is found.
>   */
> -void
> +int
>  insert_filter_info(struct filter_info *fl_info)
>  {
>  	struct filter_info *prev = NULL;
> @@ -8735,7 +8944,7 @@ insert_filter_info(struct filter_info *fl_info)
>  
>  	if (!ptr) {
>  		filter_info = fl_info;
> -		return;
> +		return 1;
>  	}
>  
>  	while (ptr) {
> @@ -8748,7 +8957,7 @@ insert_filter_info(struct filter_info *fl_info)
>  		if (fl_info->size > ptr->size)
>  			ptr->size = fl_info->size;
>  		free(fl_info);
> -		return;
> +		return 0;
>  	}
>  
>  	if (prev) {
> @@ -8759,7 +8968,80 @@ insert_filter_info(struct filter_info *fl_info)
>  		fl_info->next = filter_info;
>  		filter_info = fl_info;
>  	}
> -	return;
> +	return 1;
> +}
> +
> +/*
> + * Create an erase info node for each erase command. One node per erase
> + * command even if it is part of loop construct.
> + * For erase commands that are not part of loop construct, the num_sizes will
> + * always be 1
> + * For erase commands that are part of loop construct, the num_sizes may be
> + * 1 or >1 depending on number iterations. This function will called multiple
> + * times depending on iterations. At first invokation create a node and
> + * increment num_sizes for subsequent invokations.
> + *
> + * The valid erase info node starts from index value 1. (index 0 is invalid
> + * index).
> + *
> + *            Index 0     1        2        3
> + *             +------+--------+--------+--------+
> + * erase_info->|Unused|        |        |        |......
> + *             +------+--------+--------+--------+
> + *                        |        .        .        .....
> + *                        V
> + *                   +---------+
> + *                   | char*   |----> Original erase command string
> + *                   +---------+
> + *                   |num_sizes|
> + *                   +---------+      +--+--+--+
> + *                   | sizes   |----> |  |  |  |... Sizes array of num_sizes
> + *                   +---------+      +--+--+--+
> + *
> + * On success, return the index value of erase node for given erase command.
> + * On failure, return 0.
> + */
> +static int
> +add_erase_info_node(struct config_entry *filter_symbol)
> +{
> +	int idx = filter_symbol->erase_info_idx;
> +
> +	/*
> +	 * Check if node is already created, if yes, increment the num_sizes.
> +	 */
> +	if (idx) {
> +		erase_info[idx].num_sizes++;
> +		return idx;
> +	}
> +
> +	/* Allocate a new node. */
> +	DEBUG_MSG("Allocating new erase info node for command \"%s\"\n",
> +			filter_symbol->symbol_expr);
> +	idx = num_erase_info++;
> +	erase_info = realloc(erase_info,
> +			sizeof(struct erase_info) * num_erase_info);
> +	if (!erase_info) {
> +		ERRMSG("Can't get memory to create erase information.\n");
> +		return 0;
> +	}
> +
> +	memset(&erase_info[idx], 0, sizeof(struct erase_info));
> +	erase_info[idx].symbol_expr = filter_symbol->symbol_expr;
> +	erase_info[idx].num_sizes = 1;
> +
> +	filter_symbol->symbol_expr = NULL;
> +	filter_symbol->erase_info_idx = idx;
> +
> +	return idx;
> +}
> +
> +/* Return the index value in sizes array for given erase command index. */
> +static inline int
> +get_size_index(int ei_idx)
> +{
> +	if (ei_idx)
> +		return erase_info[ei_idx].num_sizes - 1;
> +	return 0;
>  }
>  
>  int
> @@ -8798,7 +9080,10 @@ update_filter_info(struct config_entry *filter_symbol,
>  	fl_info->size = size;
>  	fl_info->nullify = filter_symbol->nullify;
>  
> -	insert_filter_info(fl_info);
> +	if (insert_filter_info(fl_info)) {
> +		fl_info->erase_info_idx = add_erase_info_node(filter_symbol);
> +		fl_info->size_idx = get_size_index(fl_info->erase_info_idx);
> +	}
>  	return TRUE;
>  }
>  
> @@ -9049,6 +9334,7 @@ void
>  clear_filter_info(void)
>  {
>  	struct filter_info *prev, *fi = filter_info;
> +	int i;
>  
>  	/* Delete filter_info nodes that are left out. */
>  	while (fi) {
> @@ -9057,6 +9343,13 @@ clear_filter_info(void)
>  		free(prev);
>  	}
>  	filter_info = NULL;
> +	if (erase_info) {
> +		for (i = 1; i < num_erase_info; i++) {
> +			free(erase_info[i].symbol_expr);
> +			free(erase_info[i].sizes);
> +		}
> +		free(erase_info);
> +	}
>  }
>  
>  int
> @@ -9245,6 +9538,8 @@ store_splitting_info(void)
>  		}
>  		SPLITTING_START_PFN(i) = kh.start_pfn;
>  		SPLITTING_END_PFN(i)   = kh.end_pfn;
> +		SPLITTING_OFFSET_EI(i) = kh.offset_eraseinfo;
> +		SPLITTING_SIZE_EI(i)   = kh.size_eraseinfo;
>  	}
>  	return TRUE;
>  }
> @@ -9452,6 +9747,7 @@ reassemble_kdump_pages(void)
>  	struct cache_data cd_pd, cd_data;
>  	struct timeval tv_start;
>  	char *data = NULL;
> +	unsigned long data_buf_size = info->page_size;
>  
>  	initialize_2nd_bitmap(&bitmap2);
>  
> @@ -9465,7 +9761,7 @@ reassemble_kdump_pages(void)
>  		free_cache_data(&cd_pd);
>  		return FALSE;
>  	}
> -	if ((data = malloc(info->page_size)) == NULL) {
> +	if ((data = malloc(data_buf_size)) == NULL) {
>  		ERRMSG("Can't allcate memory for page data.\n");
>  		free_cache_data(&cd_pd);
>  		free_cache_data(&cd_data);
> @@ -9570,6 +9866,49 @@ reassemble_kdump_pages(void)
>  	if (!write_cache_bufsz(&cd_data))
>  		goto out;
>  
> +	info->offset_eraseinfo = cd_data.offset;
> +	/* Copy eraseinfo from split dumpfiles to o/p dumpfile */
> +	for (i = 0; i < info->num_dumpfile; i++) {
> +		if (!SPLITTING_SIZE_EI(i))
> +			continue;
> +
> +		if (SPLITTING_SIZE_EI(i) > data_buf_size) {
> +			data_buf_size = SPLITTING_SIZE_EI(i);
> +			if ((data = realloc(data, data_buf_size)) == NULL) {
> +				ERRMSG("Can't allcate memory for eraseinfo"
> +					" data.\n");
> +				goto out;
> +			}
> +		}
> +		if ((fd = open(SPLITTING_DUMPFILE(i), O_RDONLY)) < 0) {
> +			ERRMSG("Can't open a file(%s). %s\n",
> +			    SPLITTING_DUMPFILE(i), strerror(errno));
> +			goto out;
> +		}
> +		if (lseek(fd, SPLITTING_OFFSET_EI(i), SEEK_SET) < 0) {
> +			ERRMSG("Can't seek a file(%s). %s\n",
> +			    SPLITTING_DUMPFILE(i), strerror(errno));
> +			goto out;
> +		}
> +		if (read(fd, data, SPLITTING_SIZE_EI(i)) !=
> +						SPLITTING_SIZE_EI(i)) {
> +			ERRMSG("Can't read a file(%s). %s\n",
> +			    SPLITTING_DUMPFILE(i), strerror(errno));
> +			goto out;
> +		}
> +		if (!write_cache(&cd_data, data, SPLITTING_SIZE_EI(i)))
> +			goto out;
> +		info->size_eraseinfo += SPLITTING_SIZE_EI(i);
> +
> +		close(fd);
> +		fd = 0;
> +	}
> +	if (!write_cache_bufsz(&cd_data))
> +		goto out;
> +
> +	if (!update_sub_header())
> +		goto out;
> +
>  	print_progress(PROGRESS_COPY, num_dumpable, num_dumpable);
>  	print_execution_time(PROGRESS_COPY, &tv_start);
>  
> diff --git a/makedumpfile.h b/makedumpfile.h
> index 1c61edb..2e4b902 100644
> --- a/makedumpfile.h
> +++ b/makedumpfile.h
> @@ -434,6 +434,8 @@ do { \
>  #define SPLITTING_FD_BITMAP(i)	info->splitting_info[i].fd_bitmap
>  #define SPLITTING_START_PFN(i)	info->splitting_info[i].start_pfn
>  #define SPLITTING_END_PFN(i)	info->splitting_info[i].end_pfn
> +#define SPLITTING_OFFSET_EI(i)	info->splitting_info[i].offset_eraseinfo
> +#define SPLITTING_SIZE_EI(i)	info->splitting_info[i].size_eraseinfo
>  
>  /*
>   * kernel version
> @@ -499,6 +501,8 @@ do { \
>  #define XEN_ELFNOTE_CRASH_INFO	(0x1000001)
>  #define SIZE_XEN_CRASH_INFO_V2	(sizeof(unsigned long) * 10)
>  
> +#define MAX_SIZE_STR_LEN (21)
> +
>  /*
>   * The value of dependence on machine
>   */
> @@ -841,6 +845,8 @@ struct splitting_info {
>  	int 			fd_bitmap;
>  	unsigned long long	start_pfn;
>  	unsigned long long	end_pfn;
> +	off_t			offset_eraseinfo;
> +	unsigned long		size_eraseinfo;
>  } splitting_info_t;
>  
>  struct DumpInfo {
> @@ -905,6 +911,7 @@ struct DumpInfo {
>  	struct dump_bitmap 		*bitmap1;
>  	struct dump_bitmap 		*bitmap2;
>  	struct disk_dump_header		*dump_header;
> +	struct kdump_sub_header		sub_header;
>  
>  	/*
>  	 * ELF header info:
> @@ -973,6 +980,12 @@ struct DumpInfo {
>  	unsigned long		size_note;
>  
>  	/*
> +	 * erased information in dump memory image info:
> +	 */
> +	off_t			offset_eraseinfo;
> +	unsigned long		size_eraseinfo;
> +
> +	/*
>  	 * for Xen extraction
>  	 */
>  	off_t			offset_xen_crash_info;
> @@ -1280,12 +1293,27 @@ struct dwarf_info {
>  extern struct dwarf_info	dwarf_info;
>  
>  /*
> + * Erase information, original symbol expressions.
> + */
> +struct erase_info {
> +	char		*symbol_expr;
> +	int		num_sizes;
> +	long		*sizes;
> +	int		erased;		/* 1= erased, 0= Not erased */
> +};
> +
> +/*
>   * Filtering information
>   */
>  struct filter_info {
>  	unsigned long long      address;
>  	unsigned long long      paddr;
>  	long			size;
> +
> +	/* direct access to update erase information node */
> +	int			erase_info_idx;	/* 0= invalid index */
> +	int			size_idx;
> +
>  	struct filter_info      *next;
>  	unsigned short          nullify;
>  };
> @@ -1293,6 +1321,7 @@ struct filter_info {
>  struct config_entry {
>  	char			*name;
>  	char			*type_name;
> +	char			*symbol_expr;	/* original symbol expression */
>  	unsigned short		flag;
>  	unsigned short		nullify;
>  	unsigned long long	sym_addr;	/* Symbol address */
> @@ -1305,6 +1334,7 @@ struct config_entry {
>  	long			index;
>  	long			size;
>  	int			line;	/* Line number in config file. */
> +	int			erase_info_idx;	/* 0= invalid index */
>  	struct config_entry	*refer_to;
>  	struct config_entry	*next;
>  };
> 


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Re: [PATCH v2 7/8] makedumpfile: Add erased information in compressed kdump file

[Ken'ichi Ohmichi]

Hi Mahesh,

On Wed, 18 May 2011 01:36:17 +0530
Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> wrote:
> @@ -9452,6 +9747,7 @@ reassemble_kdump_pages(void)
>  	struct cache_data cd_pd, cd_data;
>  	struct timeval tv_start;
>  	char *data = NULL;
> +	unsigned long data_buf_size = info->page_size;
>  
>  	initialize_2nd_bitmap(&bitmap2);
>  
> @@ -9465,7 +9761,7 @@ reassemble_kdump_pages(void)
>  		free_cache_data(&cd_pd);
>  		return FALSE;
>  	}
> -	if ((data = malloc(info->page_size)) == NULL) {
> +	if ((data = malloc(data_buf_size)) == NULL) {
>  		ERRMSG("Can't allcate memory for page data.\n");
>  		free_cache_data(&cd_pd);
>  		free_cache_data(&cd_data);
> @@ -9570,6 +9866,49 @@ reassemble_kdump_pages(void)
>  	if (!write_cache_bufsz(&cd_data))
>  		goto out;
>  
> +	info->offset_eraseinfo = cd_data.offset;
> +	/* Copy eraseinfo from split dumpfiles to o/p dumpfile */
> +	for (i = 0; i < info->num_dumpfile; i++) {
> +		if (!SPLITTING_SIZE_EI(i))
> +			continue;
> +
> +		if (SPLITTING_SIZE_EI(i) > data_buf_size) {
> +			data_buf_size = SPLITTING_SIZE_EI(i);
> +			if ((data = realloc(data, data_buf_size)) == NULL) {
> +				ERRMSG("Can't allcate memory for eraseinfo"
> +					" data.\n");
> +				goto out;
> +			}
> +		}
> +		if ((fd = open(SPLITTING_DUMPFILE(i), O_RDONLY)) < 0) {
> +			ERRMSG("Can't open a file(%s). %s\n",
> +			    SPLITTING_DUMPFILE(i), strerror(errno));
> +			goto out;
> +		}
> +		if (lseek(fd, SPLITTING_OFFSET_EI(i), SEEK_SET) < 0) {
> +			ERRMSG("Can't seek a file(%s). %s\n",
> +			    SPLITTING_DUMPFILE(i), strerror(errno));
> +			goto out;
> +		}
> +		if (read(fd, data, SPLITTING_SIZE_EI(i)) !=
> +						SPLITTING_SIZE_EI(i)) {
> +			ERRMSG("Can't read a file(%s). %s\n",
> +			    SPLITTING_DUMPFILE(i), strerror(errno));
> +			goto out;
> +		}
> +		if (!write_cache(&cd_data, data, SPLITTING_SIZE_EI(i)))
> +			goto out;
> +		info->size_eraseinfo += SPLITTING_SIZE_EI(i);
> +
> +		close(fd);
> +		fd = 0;
> +	}
> +	if (!write_cache_bufsz(&cd_data))
> +		goto out;
> +
> +	if (!update_sub_header())
> +		goto out;

The above update_sub_header() breaks "--reassemble" option if a dumpfile
does not contain eraseinfo data :

---
# makedumpfile --split -d30 vmcore dump.1 dump.2
Copying data                       : [100 %]
Copying data                       : [100 %]

The dumpfiles are saved to dump.1, and dump.2.

makedumpfile Completed.
# makedumpfile --reassemble dump.1 dump.2 dump.3
Copying data                       : [100 %]
The dumpfile is saved to dump.3.

makedumpfile Completed.
# crash vmlinux dump.3
[..]

crash: page excluded: kernel virtual address: ffffffff8040b220  type: "cpu_possible_mask"
#
---

The cause is that info->sub_header, which is written in update_sub_header(),
is filled with 0x0.
The following change fixes this problem:

---
@@ -9378,6 +9680,7 @@ reassemble_kdump_header(void)
                    info->name_dumpfile, strerror(errno));
                return FALSE;
        }
+       memcpy(&info->sub_header, &kh, sizeof(kh));

        /*
         * Write dump bitmap to both a dumpfile and a bitmap file.
---

Thanks
Ken'ichi Ohmichi

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Re: [PATCH v2 7/8] makedumpfile: Add erased information in compressed kdump file

[Mahesh Jagannath Salgaonkar]

Hi Ken'ichi,

On 08/16/2011 06:30 AM, Ken'ichi Ohmichi wrote:
> 
> Hi Mahesh,
> 
> On Wed, 18 May 2011 01:36:17 +0530
> Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> wrote:
>> @@ -9452,6 +9747,7 @@ reassemble_kdump_pages(void)
>>  	struct cache_data cd_pd, cd_data;
>>  	struct timeval tv_start;
>>  	char *data = NULL;
>> +	unsigned long data_buf_size = info->page_size;
>>  
>>  	initialize_2nd_bitmap(&bitmap2);
>>  
>> @@ -9465,7 +9761,7 @@ reassemble_kdump_pages(void)
>>  		free_cache_data(&cd_pd);
>>  		return FALSE;
>>  	}
>> -	if ((data = malloc(info->page_size)) == NULL) {
>> +	if ((data = malloc(data_buf_size)) == NULL) {
>>  		ERRMSG("Can't allcate memory for page data.\n");
>>  		free_cache_data(&cd_pd);
>>  		free_cache_data(&cd_data);
>> @@ -9570,6 +9866,49 @@ reassemble_kdump_pages(void)
>>  	if (!write_cache_bufsz(&cd_data))
>>  		goto out;
>>  
>> +	info->offset_eraseinfo = cd_data.offset;
>> +	/* Copy eraseinfo from split dumpfiles to o/p dumpfile */
>> +	for (i = 0; i < info->num_dumpfile; i++) {
>> +		if (!SPLITTING_SIZE_EI(i))
>> +			continue;
>> +
>> +		if (SPLITTING_SIZE_EI(i) > data_buf_size) {
>> +			data_buf_size = SPLITTING_SIZE_EI(i);
>> +			if ((data = realloc(data, data_buf_size)) == NULL) {
>> +				ERRMSG("Can't allcate memory for eraseinfo"
>> +					" data.\n");
>> +				goto out;
>> +			}
>> +		}
>> +		if ((fd = open(SPLITTING_DUMPFILE(i), O_RDONLY)) < 0) {
>> +			ERRMSG("Can't open a file(%s). %s\n",
>> +			    SPLITTING_DUMPFILE(i), strerror(errno));
>> +			goto out;
>> +		}
>> +		if (lseek(fd, SPLITTING_OFFSET_EI(i), SEEK_SET) < 0) {
>> +			ERRMSG("Can't seek a file(%s). %s\n",
>> +			    SPLITTING_DUMPFILE(i), strerror(errno));
>> +			goto out;
>> +		}
>> +		if (read(fd, data, SPLITTING_SIZE_EI(i)) !=
>> +						SPLITTING_SIZE_EI(i)) {
>> +			ERRMSG("Can't read a file(%s). %s\n",
>> +			    SPLITTING_DUMPFILE(i), strerror(errno));
>> +			goto out;
>> +		}
>> +		if (!write_cache(&cd_data, data, SPLITTING_SIZE_EI(i)))
>> +			goto out;
>> +		info->size_eraseinfo += SPLITTING_SIZE_EI(i);
>> +
>> +		close(fd);
>> +		fd = 0;
>> +	}
>> +	if (!write_cache_bufsz(&cd_data))
>> +		goto out;
>> +
>> +	if (!update_sub_header())
>> +		goto out;
> 
> The above update_sub_header() breaks "--reassemble" option if a dumpfile
> does not contain eraseinfo data :

My bad. Thanks for catching it.

Thanks,
-Mahesh.

> 
> ---
> # makedumpfile --split -d30 vmcore dump.1 dump.2
> Copying data                       : [100 %]
> Copying data                       : [100 %]
> 
> The dumpfiles are saved to dump.1, and dump.2.
> 
> makedumpfile Completed.
> # makedumpfile --reassemble dump.1 dump.2 dump.3
> Copying data                       : [100 %]
> The dumpfile is saved to dump.3.
> 
> makedumpfile Completed.
> # crash vmlinux dump.3
> [..]
> 
> crash: page excluded: kernel virtual address: ffffffff8040b220  type: "cpu_possible_mask"
> #
> ---
> 
> The cause is that info->sub_header, which is written in update_sub_header(),
> is filled with 0x0.
> The following change fixes this problem:
> 
> ---
> @@ -9378,6 +9680,7 @@ reassemble_kdump_header(void)
>                     info->name_dumpfile, strerror(errno));
>                 return FALSE;
>         }
> +       memcpy(&info->sub_header, &kh, sizeof(kh));
> 
>         /*
>          * Write dump bitmap to both a dumpfile and a bitmap file.
> ---
> 
> Thanks
> Ken'ichi Ohmichi
> 
> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec


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Re: [PATCH v2 7/8] makedumpfile: Add erased information in compressed kdump file

[Mahesh Jagannath Salgaonkar]

Hi Ken'ichi,

On 08/12/2011 01:40 PM, Ken'ichi Ohmichi wrote:
> 
> Hi Mahesh,
> 
> On Wed, 18 May 2011 01:36:17 +0530
> Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> wrote:
>> --- a/makedumpfile.c
>> +++ b/makedumpfile.c
>> @@ -29,6 +29,8 @@ struct DumpInfo		*info = NULL;
>>  struct module_sym_table	mod_st = { 0 };
>>  struct filter_info	*filter_info = NULL;
>>  struct filter_config	filter_config;
>> +struct erase_info	*erase_info = NULL;
>> +unsigned long		num_erase_info = 1; /* Node 0 is unused. */
> 
> I cannot understand erase_info[0] is unused.

I did this to avoid the explicit need of initializing erase_info_idx
member from struct config_entry and struct filter_info with some other
invalid value, instead I thought I will use '0' as invalid index.

Do you think I should change this patch to use '-1' as invalid index?

> 
> 
>> @@ -6000,10 +6007,17 @@ write_kdump_header(void)
>>  			kh.size_vmcoreinfo = info->size_vmcoreinfo;
>>  		}
>>  	}
>> -	if (!write_buffer(info->fd_dumpfile, dh->block_size, &kh,
>> -	    size, info->name_dumpfile))
>> -		goto out;
>> +	/*
>> +	 * While writing dump data to STDOUT, delay the writing of sub header
>> +	 * untill we gather erase info offset and size.
>> +	 */
>> +	if (!info->flag_flatten) {
>> +		if (!write_buffer(info->fd_dumpfile, dh->block_size, &kh,
>> +		    size, info->name_dumpfile))
>> +			goto out;
>> +	}
> 
> Does makedumpfile work wrong if removing the above change ?
> 

Hmm.. while implementing this patch I thought we may run into issues if
we write sub_header data twice for flattened case. But it seems the '-R'
option rearranges the data properly.

I agree that we dont need above change. Thanks for catching this.

Thanks,
-Mahesh.

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Re: [PATCH v2 7/8] makedumpfile: Add erased information in compressed kdump file

[Ken'ichi Ohmichi]

Hi Mahesh,

On Thu, 18 Aug 2011 13:44:12 +0530
Mahesh Jagannath Salgaonkar <mahesh@linux.vnet.ibm.com> wrote:
> >> --- a/makedumpfile.c
> >> +++ b/makedumpfile.c
> >> @@ -29,6 +29,8 @@ struct DumpInfo		*info = NULL;
> >>  struct module_sym_table	mod_st = { 0 };
> >>  struct filter_info	*filter_info = NULL;
> >>  struct filter_config	filter_config;
> >> +struct erase_info	*erase_info = NULL;
> >> +unsigned long		num_erase_info = 1; /* Node 0 is unused. */
> > 
> > I cannot understand erase_info[0] is unused.
> 
> I did this to avoid the explicit need of initializing erase_info_idx
> member from struct config_entry and struct filter_info with some other
> invalid value, instead I thought I will use '0' as invalid index.

Thank you for the explanation. I can understand your thought.
I think current code is right and we don't need to change the code.
Sorry about my noise.


> >> @@ -6000,10 +6007,17 @@ write_kdump_header(void)
> >>  			kh.size_vmcoreinfo = info->size_vmcoreinfo;
> >>  		}
> >>  	}
> >> -	if (!write_buffer(info->fd_dumpfile, dh->block_size, &kh,
> >> -	    size, info->name_dumpfile))
> >> -		goto out;
> >> +	/*
> >> +	 * While writing dump data to STDOUT, delay the writing of sub header
> >> +	 * untill we gather erase info offset and size.
> >> +	 */
> >> +	if (!info->flag_flatten) {
> >> +		if (!write_buffer(info->fd_dumpfile, dh->block_size, &kh,
> >> +		    size, info->name_dumpfile))
> >> +			goto out;
> >> +	}
> > 
> > Does makedumpfile work wrong if removing the above change ?
> > 
> 
> Hmm.. while implementing this patch I thought we may run into issues if
> we write sub_header data twice for flattened case. But it seems the '-R'
> option rearranges the data properly.
> 
> I agree that we dont need above change. Thanks for catching this.

OK, I will revert the above change.


Thanks
Ken'ichi Ohmichi

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Re: [PATCH v2 7/8] makedumpfile: Add erased information in compressed kdump file

[Ken'ichi Ohmichi]

Hi Mahesh,

Sorry about many responses of this patch.

On Wed, 18 May 2011 01:36:17 +0530
Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> wrote:
>
> From: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
> 
> Include the erase information in the makedumpfile generated dumpfile. The
> erased information contains only effective lines from the filter
> configuration file. This patch supports inclusion of erase information in
> kdump compressed, flatten and split dumpfiles. On re-filtering, the erase
> information from input dumpfile (if any) will be carried over to resulting
> dumpfile.
> 
> This patch introduces new members offset_eraseinfo, size_eraseinfo into the
> sub header in compressed kdump file.
> 
> The erased information would contain *multiple* erased symbol names.
> For example, the following is based on your above example.
> 
> 	struct S1 {
> 		int a;
> 		int b;
> 		int c;
> 	};
> 	struct S2 {
> 		struct S1 *mystruct1;
> 		struct S1 *mystruct2;
> 	};
> 
> 	struct S2 mystruct2;
> 
> 	#Filter command
> 	erase mystruct2.mystruct1.a
> 	erase mystruct2.mystruct1.c
> 	erase mystruct2.mystruct2.b
> 
> 	#The erased information
> 	erase mystruct2.mystruct1.a 4
> 	erase mystruct2.mystruct1.c 4
> 	erase mystruct2.mystruct2.b 4

While testing this feature, I noticed the description format of
makedumpfile.conf is different from the one of eraseinfo.
The former contains "size", but the later does not.

I feel the same format will be useful.
Are there any reasons of different formats ?


Thanks
Ken'ichi Ohmichi

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Re: [PATCH v2 7/8] makedumpfile: Add erased information in compressed kdump file

[Mahesh J Salgaonkar]

On 2011-08-19 15:16:59 Fri, Ken'ichi Ohmichi wrote:
> 
> Hi Mahesh,
> 
> Sorry about many responses of this patch.
> 
> On Wed, 18 May 2011 01:36:17 +0530
> Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> wrote:
> >
> > From: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
> > 
> > Include the erase information in the makedumpfile generated dumpfile. The
> > erased information contains only effective lines from the filter
> > configuration file. This patch supports inclusion of erase information in
> > kdump compressed, flatten and split dumpfiles. On re-filtering, the erase
> > information from input dumpfile (if any) will be carried over to resulting
> > dumpfile.
> > 
> > This patch introduces new members offset_eraseinfo, size_eraseinfo into the
> > sub header in compressed kdump file.
> > 
> > The erased information would contain *multiple* erased symbol names.
> > For example, the following is based on your above example.
> > 
> > 	struct S1 {
> > 		int a;
> > 		int b;
> > 		int c;
> > 	};
> > 	struct S2 {
> > 		struct S1 *mystruct1;
> > 		struct S1 *mystruct2;
> > 	};
> > 
> > 	struct S2 mystruct2;
> > 
> > 	#Filter command
> > 	erase mystruct2.mystruct1.a
> > 	erase mystruct2.mystruct1.c
> > 	erase mystruct2.mystruct2.b
> > 
> > 	#The erased information
> > 	erase mystruct2.mystruct1.a 4
> > 	erase mystruct2.mystruct1.c 4
> > 	erase mystruct2.mystruct2.b 4
> 
> While testing this feature, I noticed the description format of
> makedumpfile.conf is different from the one of eraseinfo.
> The former contains "size", but the later does not.
> 
> Are there any reasons of different formats ?

There is no specific reason, since it is just an information I thought we
can follow a simple format.

> I feel the same format will be useful.

Sure, will make the change.

Thanks,
-Mahesh.

> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
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-- 
Mahesh J Salgaonkar

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Re: [PATCH v2 7/8] makedumpfile: Add erased information in compressed kdump file

[Mahesh J Salgaonkar]

On 2011-08-22 17:27:58 Mon, Mahesh J Salgaonkar wrote:
> On 2011-08-19 15:16:59 Fri, Ken'ichi Ohmichi wrote:
> > 
> > Hi Mahesh,
> > 
> > Sorry about many responses of this patch.
> > 
> > On Wed, 18 May 2011 01:36:17 +0530
> > Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> wrote:
> > >
> > > From: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
> > > 
> > > Include the erase information in the makedumpfile generated dumpfile. The
> > > erased information contains only effective lines from the filter
> > > configuration file. This patch supports inclusion of erase information in
> > > kdump compressed, flatten and split dumpfiles. On re-filtering, the erase
> > > information from input dumpfile (if any) will be carried over to resulting
> > > dumpfile.
> > > 
> > > This patch introduces new members offset_eraseinfo, size_eraseinfo into the
> > > sub header in compressed kdump file.
> > > 
> > > The erased information would contain *multiple* erased symbol names.
> > > For example, the following is based on your above example.
> > > 
> > > 	struct S1 {
> > > 		int a;
> > > 		int b;
> > > 		int c;
> > > 	};
> > > 	struct S2 {
> > > 		struct S1 *mystruct1;
> > > 		struct S1 *mystruct2;
> > > 	};
> > > 
> > > 	struct S2 mystruct2;
> > > 
> > > 	#Filter command
> > > 	erase mystruct2.mystruct1.a
> > > 	erase mystruct2.mystruct1.c
> > > 	erase mystruct2.mystruct2.b
> > > 
> > > 	#The erased information
> > > 	erase mystruct2.mystruct1.a 4
> > > 	erase mystruct2.mystruct1.c 4
> > > 	erase mystruct2.mystruct2.b 4
> > 
> > While testing this feature, I noticed the description format of
> > makedumpfile.conf is different from the one of eraseinfo.
> > The former contains "size", but the later does not.
> > 
> > Are there any reasons of different formats ?
> 
> There is no specific reason, since it is just an information I thought we
> can follow a simple format.
> 
> > I feel the same format will be useful.
> 
> Sure, will make the change.
> 
> Thanks,
> -Mahesh.

Hi Ken'ichi,

Please find the patch below that now maintain the same format for
eraseinfo data.

Thanks,
-Mahesh.


makedumpfile: Use the same format as erase commands for eraseinfo data.

From: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>

The format of eraseinfo data differs from that of erase commands. This patch
makes sure eraseinfo data format is same as erase commands.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
---
 IMPLEMENTATION |    4 ++--
 makedumpfile.c |    4 ++--
 makedumpfile.h |    2 +-
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/IMPLEMENTATION b/IMPLEMENTATION
index c11bd36..f0f3135 100644
--- a/IMPLEMENTATION
+++ b/IMPLEMENTATION
@@ -26,9 +26,9 @@
     |                        :                 |
     |         page data (pfn Z)                |
     +------------------------------------------+ offset_eraseinfo
-    | erase mystruct2.mystruct1.var 4          |
+    | erase mystruct2.mystruct1.var size 4     |
     | erase mystruct2.mystruct1.ptr nullify    |
-    | erase mystruct2.mystruct.array 100       |
+    | erase mystruct2.mystruct.array size 100  |
     +------------------------------------------+
 
 
diff --git a/makedumpfile.c b/makedumpfile.c
index 1a88171..2c49bbe 100644
--- a/makedumpfile.c
+++ b/makedumpfile.c
@@ -3949,7 +3949,7 @@ write_elf_header(struct cache_data *cd_header)
 		if (fl_info->nullify)
 			sprintf(size_str, "nullify\n");
 		else
-			sprintf(size_str, "%ld\n", fl_info->size);
+			sprintf(size_str, "size %ld\n", fl_info->size);
 
 		size_eraseinfo += strlen("erase ") +
 				strlen(ei->symbol_expr) + 1 +
@@ -4799,7 +4799,7 @@ write_eraseinfo(struct cache_data *cd_page, unsigned long *size_out)
 			continue;
 		for (j = 0; j < erase_info[i].num_sizes; j++) {
 			if (erase_info[i].sizes[j] > 0)
-				sprintf(size_str, "%ld\n",
+				sprintf(size_str, "size %ld\n",
 						erase_info[i].sizes[j]);
 			else if (erase_info[i].sizes[j] == -1)
 				sprintf(size_str, "nullify\n");
diff --git a/makedumpfile.h b/makedumpfile.h
index 8b1bd4f..2741903 100644
--- a/makedumpfile.h
+++ b/makedumpfile.h
@@ -411,7 +411,7 @@ do { \
 
 #define SIZE_XEN_CRASH_INFO_V2	(sizeof(unsigned long) * 10)
 
-#define MAX_SIZE_STR_LEN (21)
+#define MAX_SIZE_STR_LEN (26)	/* strlen("size ") + 21 */
 
 /*
  * The value of dependence on machine


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Re: [PATCH v2 7/8] makedumpfile: Add erased information in compressed kdump file

[Ken'ichi Ohmichi]

Hi Mahesh,

Thank you for the patch.

On Tue, 6 Sep 2011 21:14:52 +0530
Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> wrote:
> 
> makedumpfile: Use the same format as erase commands for eraseinfo data.
> 
> From: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
> 
> The format of eraseinfo data differs from that of erase commands. This patch
> makes sure eraseinfo data format is same as erase commands.
> 
> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>

Acked-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>


Thanks
Ken'ichi Ohmichi

> ---
>  IMPLEMENTATION |    4 ++--
>  makedumpfile.c |    4 ++--
>  makedumpfile.h |    2 +-
>  3 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/IMPLEMENTATION b/IMPLEMENTATION
> index c11bd36..f0f3135 100644
> --- a/IMPLEMENTATION
> +++ b/IMPLEMENTATION
> @@ -26,9 +26,9 @@
>      |                        :                 |
>      |         page data (pfn Z)                |
>      +------------------------------------------+ offset_eraseinfo
> -    | erase mystruct2.mystruct1.var 4          |
> +    | erase mystruct2.mystruct1.var size 4     |
>      | erase mystruct2.mystruct1.ptr nullify    |
> -    | erase mystruct2.mystruct.array 100       |
> +    | erase mystruct2.mystruct.array size 100  |
>      +------------------------------------------+
>  
>  
> diff --git a/makedumpfile.c b/makedumpfile.c
> index 1a88171..2c49bbe 100644
> --- a/makedumpfile.c
> +++ b/makedumpfile.c
> @@ -3949,7 +3949,7 @@ write_elf_header(struct cache_data *cd_header)
>  		if (fl_info->nullify)
>  			sprintf(size_str, "nullify\n");
>  		else
> -			sprintf(size_str, "%ld\n", fl_info->size);
> +			sprintf(size_str, "size %ld\n", fl_info->size);
>  
>  		size_eraseinfo += strlen("erase ") +
>  				strlen(ei->symbol_expr) + 1 +
> @@ -4799,7 +4799,7 @@ write_eraseinfo(struct cache_data *cd_page, unsigned long *size_out)
>  			continue;
>  		for (j = 0; j < erase_info[i].num_sizes; j++) {
>  			if (erase_info[i].sizes[j] > 0)
> -				sprintf(size_str, "%ld\n",
> +				sprintf(size_str, "size %ld\n",
>  						erase_info[i].sizes[j]);
>  			else if (erase_info[i].sizes[j] == -1)
>  				sprintf(size_str, "nullify\n");
> diff --git a/makedumpfile.h b/makedumpfile.h
> index 8b1bd4f..2741903 100644
> --- a/makedumpfile.h
> +++ b/makedumpfile.h
> @@ -411,7 +411,7 @@ do { \
>  
>  #define SIZE_XEN_CRASH_INFO_V2	(sizeof(unsigned long) * 10)
>  
> -#define MAX_SIZE_STR_LEN (21)
> +#define MAX_SIZE_STR_LEN (26)	/* strlen("size ") + 21 */
>  
>  /*
>   * The value of dependence on machine
> 


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Re: makedumpfile: Add erased information in compressed kdump file and ELF formatted dumpfile

[Dave Anderson]

Hi Mahesh,

Now that this feature is in makedumpfile-1.4.0, I presume that you
have crash utility "warning" patches underway?

Also, can you confirm that compressed or kdumps with (or without)
eraseinfo data can still be handled with no problem by the current
version of the crash utility?  I'm not talking about the ramifications
of whatever kernel data may have been erased, but whether the changes to
the dumpfile headers could cause a problem.  I'm presuming that the
compressed kdump eraseinfo data would be invisible to an older version
of crash, and that ELF kdump eraseinfo would just show up as an (unused)
ELF note -- but I just want to make sure. 

Thanks,
  Dave



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Re: makedumpfile: Add erased information in compressed kdump file and ELF formatted dumpfile

[Mahesh Jagannath Salgaonkar]

On 09/12/2011 11:54 PM, Dave Anderson wrote:
> 
> Hi Mahesh,
> 
> Now that this feature is in makedumpfile-1.4.0, I presume that you
> have crash utility "warning" patches underway?

Yup. I am working on it, will post the patches very soon.

> 
> Also, can you confirm that compressed or kdumps with (or without)
> eraseinfo data can still be handled with no problem by the current
> version of the crash utility?  I'm not talking about the ramifications
> of whatever kernel data may have been erased, but whether the changes to
> the dumpfile headers could cause a problem.  I'm presuming that the
> compressed kdump eraseinfo data would be invisible to an older version
> of crash, and that ELF kdump eraseinfo would just show up as an (unused)
> ELF note -- but I just want to make sure. 

Yes. The changes to dumpfile header and addition of eraseinfo data/ELF
note will not cause any problems with older crash version. With the
current version of crash the ELF kdump eraseinfo note would show up as
below:

Elf64_Nhdr:
               n_namesz: 10 ("ERASEINFO")
               n_descsz: 56
                 n_type: 0 (?)
                         2065736172650000 72616a5f64657263
                         697320656d616e2e 650a36353220657a
                         656e692065736172 736f746f72705f74
                         303120657a697320

Thanks,
-Mahesh.


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