From 8e124174b62376b17ac909bc68622ef07bde6840 Mon Sep 17 00:00:00 2001

Message-Id: <8e124174b62376b17ac909bc68622ef07bde6840.1382323707.git.bhe@redhat.com>

From: Jingbai Ma <jingbai.ma@hp.com>

Date: Fri, 18 Oct 2013 18:53:38 +0900

Subject: [PATCH] [PATCH v4] Fix max_mapnr issue on system has over 44-bit

 addressing.

This patch will fix a bug of makedumpfile doesn't work correctly on system

has over 44-bit addressing in compression dump mode.

This bug was posted here:

http://lists.infradead.org/pipermail/kexec/2013-September/009587.html

This patch will add 3 new fields in struct kdump_sub_header.

unsigned long long start_pfn_64;  /* header_version 6 and later */

unsigned long long end_pfn_64;    /* header_version 6 and later */

unsigned long long max_mapnr_64;  /* header_version 6 and later */

And the old "unsigned int max_mapnr" in struct disk_dump_header will

not be used anymore, but still be there for compatibility purpose.

The max_mapnr_64 only exists in strcut kdump_sub_header, and that only

for compressed kdump format, so for ELF format kdump files (non-compressed),

only the max_mapnr is available, so it still may be truncated for addresses

exceed 44bit (above 16TB).

This patch will change the header_version to 6.

The corresponding patch for crash utility can be found here:

http://lists.infradead.org/pipermail/kexec/2013-October/009750.html

This patch doesn't change sadump_header.

Changelog:

v4:

- Do not change max_mapnr_64 in kdump_sub_header in memory for old kernel.

v3:

- Change notes for max_mapnr, start_pfn and end_pfn as obsolete.

- Remove "(32bit)" from debug messages of max_mapnr, start_pfn and end_pfn.

- Set the 32bit start_pfn and end_pfn to UINT_MAX.

- Remove bitmap writting enhancement to another seperate patch.

- Change type of len_bitmap in struct DumpInfo back to unsigned long.

v2:

- Rename max_mapnr in struct kdump_sub_header to max_mapnr_64.

- Change type of max_mapnr_64 from unsigned long to unsigned long long.

  In x86 PAE mode on x86_32 kernel, the address may exceeds 44bit limit.

- Add start_pfn_64, end_pfn_64 for struct kdump_sub_header.

- Only print 64bit start_pfn_64, end_pfn_64 and max_mapnr_64

  debug messages for disk dump header version >= 6.

- Change type of bitmap_len in struct DumpInfo, from unsigned long to

  unsigned long long.

- Enhance bitmap writting function in reassemble_kdump_header().

  Prevent bitmap writting failure if the size of bitmap is too large to

  fit a sigle write.

v1:

- http://lists.infradead.org/pipermail/kexec/2013-September/009662.html

Signed-off-by: Jingbai Ma <jingbai.ma@hp.com>

Tested-by: Lisa Mitchell <lisa.mitchell@hp.com>

---

 IMPLEMENTATION | 15 ++++++++++---

 diskdump_mod.h | 15 ++++++++++---

 makedumpfile.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++------------

 3 files changed, 77 insertions(+), 20 deletions(-)

diff --git a/makedumpfile-1.5.4/IMPLEMENTATION b/makedumpfile-1.5.4/IMPLEMENTATION

index f0f3135..2f4cfd6 100644

--- a/makedumpfile-1.5.4/IMPLEMENTATION

+++ b/makedumpfile-1.5.4/IMPLEMENTATION

@@ -48,7 +48,9 @@

                                                    header in blocks */

         unsigned int            bitmap_blocks;  /* Size of Memory bitmap in

                                                    block */

-        unsigned int            max_mapnr;      /* = max_mapnr */

+        unsigned int            max_mapnr;      /* = max_mapnr, OBSOLETE!

+						   32bit only, full 64bit

+						   in sub header. */

         unsigned int            total_ram_blocks;/* Number of blocks should be

                                                    written */

         unsigned int            device_blocks;  /* Number of total blocks in

@@ -69,14 +71,21 @@

         unsigned long   phys_base;

         int             dump_level;     /* header_version 1 and later */

 	int		split;		/* header_version 2 and later */

-	unsigned long	start_pfn;	/* header_version 2 and later */

-	unsigned long	end_pfn;	/* header_version 2 and later */

+	unsigned long	start_pfn;	/* header_version 2 and later,

+					   OBSOLETE! 32bit only, full

+					   64bit in start_pfn_64. */

+	unsigned long	end_pfn;	/* header_version 2 and later,

+					   OBSOLETE! 32bit only, full

+					   64bit in end_pfn_64. */

 	off_t		offset_vmcoreinfo;/* header_version 3 and later */

 	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 */

+	unsigned long long start_pfn_64;  /* header_version 6 and later */

+	unsigned long long end_pfn_64;	  /* header_version 6 and later */

+	unsigned long long max_mapnr_64;  /* header_version 6 and later */

     };

   - 1st-bitmap

diff --git a/makedumpfile-1.5.4/diskdump_mod.h b/makedumpfile-1.5.4/diskdump_mod.h

index 00ab852..dd24eb2 100644

--- a/makedumpfile-1.5.4/diskdump_mod.h

+++ b/makedumpfile-1.5.4/diskdump_mod.h

@@ -52,7 +52,9 @@ struct disk_dump_header {

 						   header in blocks */

 	unsigned int		bitmap_blocks;	/* Size of Memory bitmap in

 						   block */

-	unsigned int		max_mapnr;	/* = max_mapnr */

+	unsigned int		max_mapnr;	/* = max_mapnr, OBSOLETE!

+						   32bit only, full 64bit

+						   in sub header. */

 	unsigned int		total_ram_blocks;/* Number of blocks should be

 						   written */

 	unsigned int		device_blocks;	/* Number of total blocks in

@@ -71,14 +73,21 @@ struct kdump_sub_header {

 	unsigned long	phys_base;

 	int		dump_level;	/* header_version 1 and later */

 	int		split;		/* header_version 2 and later */

-	unsigned long	start_pfn;	/* header_version 2 and later */

-	unsigned long	end_pfn;	/* header_version 2 and later */

+	unsigned long	start_pfn;	/* header_version 2 and later,

+					   OBSOLETE! 32bit only, full

+					   64bit in start_pfn_64. */

+	unsigned long	end_pfn;	/* header_version 2 and later,

+					   OBSOLETE! 32bit only, full

+					   64bit in end_pfn_64. */

 	off_t		offset_vmcoreinfo;/* header_version 3 and later */

 	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 */

+	unsigned long long start_pfn_64;  /* header_version 6 and later */

+	unsigned long long end_pfn_64;	  /* header_version 6 and later */

+	unsigned long long max_mapnr_64;  /* header_version 6 and later */

 };

 /* page flags */

diff --git a/makedumpfile-1.5.4/makedumpfile.c b/makedumpfile-1.5.4/makedumpfile.c

index 9892108..428c53e 100644

--- a/makedumpfile-1.5.4/makedumpfile.c

+++ b/makedumpfile-1.5.4/makedumpfile.c

@@ -23,6 +23,7 @@

 #include <stddef.h>

 #include <ctype.h>

 #include <sys/time.h>

+#include <limits.h>

 struct symbol_table	symbol_table;

 struct size_table	size_table;

@@ -125,7 +126,10 @@ get_max_mapnr(void)

 	unsigned long long max_paddr;

 	if (info->flag_refiltering) {

-		info->max_mapnr = info->dh_memory->max_mapnr;

+		if (info->dh_memory->header_version >= 6)

+			info->max_mapnr = info->kh_memory->max_mapnr_64;

+		else

+			info->max_mapnr = info->dh_memory->max_mapnr;

 		return TRUE;

 	}

@@ -802,6 +806,12 @@ get_kdump_compressed_header_info(char *filename)

 	DEBUG_MSG("  split            : %d\n", kh.split);

 	DEBUG_MSG("  start_pfn        : 0x%lx\n", kh.start_pfn);

 	DEBUG_MSG("  end_pfn          : 0x%lx\n", kh.end_pfn);

+	if (dh.header_version >= 6) {

+		/* A dumpfile contains full 64bit values. */

+		DEBUG_MSG("  start_pfn_64     : 0x%llx\n", kh.start_pfn_64);

+		DEBUG_MSG("  end_pfn_64       : 0x%llx\n", kh.end_pfn_64);

+		DEBUG_MSG("  max_mapnr_64     : 0x%llx\n", kh.max_mapnr_64);

+	}

 	info->dh_memory = malloc(sizeof(dh));

 	if (info->dh_memory == NULL) {

@@ -2799,14 +2809,16 @@ int

 initialize_bitmap_memory(void)

 {

 	struct disk_dump_header	*dh;

+	struct kdump_sub_header *kh;

 	struct dump_bitmap *bmp;

 	off_t bitmap_offset;

-	int bitmap_len, max_sect_len;

+	off_t bitmap_len, max_sect_len;

 	unsigned long pfn;

 	int i, j;

 	long block_size;

 	dh = info->dh_memory;

+	kh = info->kh_memory;

 	block_size = dh->block_size;

 	bitmap_offset

@@ -2826,7 +2838,10 @@ initialize_bitmap_memory(void)

 	bmp->offset = bitmap_offset + bitmap_len / 2;

 	info->bitmap_memory = bmp;

-	max_sect_len = divideup(dh->max_mapnr, BITMAP_SECT_LEN);

+	if (dh->header_version >= 6)

+		max_sect_len = divideup(kh->max_mapnr_64, BITMAP_SECT_LEN);

+	else

+		max_sect_len = divideup(dh->max_mapnr, BITMAP_SECT_LEN);

 	info->valid_pages = calloc(sizeof(ulong), max_sect_len);

 	if (info->valid_pages == NULL) {

 		ERRMSG("Can't allocate memory for the valid_pages. %s\n",

@@ -4743,7 +4758,7 @@ create_2nd_bitmap(void)

 int

 prepare_bitmap_buffer(void)

 {

-	unsigned long tmp;

+	unsigned long long tmp;

 	/*

 	 * Create 2 bitmaps (1st-bitmap & 2nd-bitmap) on block_size boundary.

@@ -4775,7 +4790,7 @@ prepare_bitmap_buffer(void)

 int

 prepare_bitmap_buffer_cyclic(void)

 {

-	unsigned long tmp;

+	unsigned long long tmp;

 	/*

 	 * Create 2 bitmaps (1st-bitmap & 2nd-bitmap) on block_size boundary.

@@ -5190,11 +5205,12 @@ write_kdump_header(void)

 	 * Write common header

 	 */

 	strncpy(dh->signature, KDUMP_SIGNATURE, strlen(KDUMP_SIGNATURE));

-	dh->header_version = 5;

+	dh->header_version = 6;

 	dh->block_size     = info->page_size;

 	dh->sub_hdr_size   = sizeof(kh) + size_note;

 	dh->sub_hdr_size   = divideup(dh->sub_hdr_size, dh->block_size);

-	dh->max_mapnr      = info->max_mapnr;

+	/* dh->max_mapnr may be truncated, full 64bit in kh.max_mapnr_64 */

+	dh->max_mapnr      = MIN(info->max_mapnr, UINT_MAX);

 	dh->nr_cpus        = get_nr_cpus();

 	dh->bitmap_blocks  = divideup(info->len_bitmap, dh->block_size);

 	memcpy(&dh->timestamp, &info->timestamp, sizeof(dh->timestamp));

@@ -5219,12 +5235,22 @@ write_kdump_header(void)

 	 */

 	size = sizeof(struct kdump_sub_header);

 	memset(&kh, 0, size);

+	/* 64bit max_mapnr_64 */

+	kh.max_mapnr_64 = info->max_mapnr;

 	kh.phys_base  = info->phys_base;

 	kh.dump_level = info->dump_level;

 	if (info->flag_split) {

 		kh.split = 1;

-		kh.start_pfn = info->split_start_pfn;

-		kh.end_pfn   = info->split_end_pfn;

+		/*

+		 * start_pfn and end_pfn may be truncated,

+		 * only for compatibility purpose

+		 */

+		kh.start_pfn = MIN(info->split_start_pfn, UINT_MAX);

+		kh.end_pfn   = MIN(info->split_end_pfn, UINT_MAX);

+

+		/* 64bit start_pfn_64 and end_pfn_64 */

+		kh.start_pfn_64 = info->split_start_pfn;

+		kh.end_pfn_64   = info->split_end_pfn;

 	}

 	if (has_pt_note()) {

 		/*

@@ -6470,7 +6496,7 @@ int

 write_kdump_bitmap(void)

 {

 	struct cache_data bm;

-	long buf_size;

+	long long buf_size;

 	off_t offset;

 	int ret = FALSE;

@@ -7853,10 +7879,8 @@ store_splitting_info(void)

 		if (i == 0) {

 			memcpy(&dh, &tmp_dh, sizeof(tmp_dh));

-			info->max_mapnr = dh.max_mapnr;

 			if (!set_page_size(dh.block_size))

 				return FALSE;

-			DEBUG_MSG("max_mapnr    : %llx\n", info->max_mapnr);

 			DEBUG_MSG("page_size    : %ld\n", info->page_size);

 		}

@@ -7873,11 +7897,24 @@ store_splitting_info(void)

 			return FALSE;

 		if (i == 0) {

+			if (dh.header_version >= 6)

+				info->max_mapnr = kh.max_mapnr_64;

+			else

+				info->max_mapnr = dh.max_mapnr;

+

+			DEBUG_MSG("max_mapnr    : %llx\n", info->max_mapnr);

+

 			info->dump_level = kh.dump_level;

 			DEBUG_MSG("dump_level   : %d\n", info->dump_level);

 		}

-		SPLITTING_START_PFN(i) = kh.start_pfn;

-		SPLITTING_END_PFN(i)   = kh.end_pfn;

+

+		if (dh.header_version >= 6) {

+			SPLITTING_START_PFN(i) = kh.start_pfn_64;

+			SPLITTING_END_PFN(i)   = kh.end_pfn_64;

+		} else {

+			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;

 	}

@@ -8039,6 +8076,8 @@ reassemble_kdump_header(void)

 	kh.split = 0;

 	kh.start_pfn = 0;

 	kh.end_pfn   = 0;

+	kh.start_pfn_64 = 0;

+	kh.end_pfn_64 = 0;

 	if (lseek(info->fd_dumpfile, info->page_size, SEEK_SET) < 0) {

 		ERRMSG("Can't seek a file(%s). %s\n",

-- 

1.8.3.1