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Wu Fengguang 36e15263aa kcore: add _text to KCORE_TEXT 
Extend KCORE_TEXT to cover the pages between _text and _stext, to allow
examining some important page table pages.

`readelf -a` output on x86_64 before and after patch:
	  Type           Offset             VirtAddr           PhysAddr
before    LOAD           0x00007fff8100c000 0xffffffff81009000 0x0000000000000000
after     LOAD           0x00007fff81003000 0xffffffff81000000 0x0000000000000000

The newly covered pages are:

	0xffffffff81000000 <startup_64> etc.
	0xffffffff81001000 <init_level4_pgt>
	0xffffffff81002000 <level3_ident_pgt>
	0xffffffff81003000 <level3_kernel_pgt>
	0xffffffff81004000 <level2_fixmap_pgt>
	0xffffffff81005000 <level1_fixmap_pgt>
	0xffffffff81006000 <level2_ident_pgt>
	0xffffffff81007000 <level2_kernel_pgt>
	0xffffffff81008000 <level2_spare_pgt>

Before patch, /proc/kcore shows outdated contents for the above page
table pages, for example:

	(gdb) p level3_ident_pgt
	$1 = {<text variable, no debug info>} 0xffffffff81002000 <level3_ident_pgt>
	(gdb) p/x *((pud_t *)&level3_ident_pgt)@512
	$2 = {{pud = 0x1006063}, {pud = 0x0} <repeats 511 times>}

while the real content is:

	root@hp /home/wfg# hexdump -s 0x1002000 -n 4096 /dev/mem
	1002000 6063 0100 0000 0000 8067 0000 0000 0000
	1002010 0000 0000 0000 0000 0000 0000 0000 0000
	*
	1003000

That is, on a x86_64 box with 2GB memory, we can see first-1GB / full-2GB
identity mapping before/after patch:

	(gdb) p/x *((pud_t *)&level3_ident_pgt)@512
before  $1 = {{pud = 0x1006063}, {pud = 0x0} <repeats 511 times>}
after   $1 = {{pud = 0x1006063}, {pud = 0x8067}, {pud = 0x0} <repeats 510 times>}

Obviously the content before patch is wrong.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:47 -07:00
..
9p Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs 2010-05-24 07:41:13 -07:00
adfs include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
affs include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
afs AFS: Don't put struct file on the stack 2010-05-21 18:31:28 -04:00
autofs include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
autofs4 fs/autofs4: use memdup_user 2010-05-27 09:12:41 -07:00
befs include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
bfs bfs: replace inode uid,gid,mode initialization with helper function 2010-05-21 18:31:25 -04:00
btrfs driver core: add devname module aliases to allow module on-demand auto-loading 2010-05-25 15:08:26 -07:00
cachefiles CacheFiles: Fix error handling in cachefiles_determine_cache_security() 2010-05-12 18:23:58 -07:00
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2010-05-24 07:37:52 -07:00
cifs cifs: fix noserverino handling when unix extensions are enabled 2010-05-17 20:59:21 +00:00
coda Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
configfs Fix the regression created by "set S_DEAD on unlink()..." commit 2010-05-15 07:16:33 -04:00
cramfs
debugfs include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
devpts Simplify devpts_get_sb() failure exits 2010-05-21 18:31:12 -04:00
dlm dlm: fix ast ordering for user locks 2010-04-30 14:52:51 -05:00
ecryptfs switch ecryptfs_write() to struct inode *, kill on-stack fake files 2010-05-21 18:31:28 -04:00
efs
exofs Merge branch 'for-linus' of git://git.open-osd.org/linux-open-osd 2010-05-24 07:57:41 -07:00
exportfs
ext2 ext2: replace inode uid,gid,mode init with helper 2010-05-21 18:31:24 -04:00
ext3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2010-05-21 19:37:45 -07:00
ext4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2010-05-21 19:37:45 -07:00
fat fatfs: ratelimit corruption report 2010-05-25 08:07:04 -07:00
freevxfs include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
fscache fs/fscache/object-list.c: fix warning on 32-bit 2010-05-26 08:19:23 -07:00
fuse driver core: add devname module aliases to allow module on-demand auto-loading 2010-05-25 15:08:26 -07:00
gfs2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes 2010-05-25 08:17:51 -07:00
hfs include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
hfsplus hfsplus: Push down BKL into ioctl function 2010-05-17 05:27:03 +02:00
hostfs include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
hpfs include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
hppfs hppfs can use existing proc_mnt, no need for do_kern_mount() in there 2010-03-03 14:08:00 -05:00
hugetlbfs
isofs include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
jbd ext3: Fix waiting on transaction during fsync 2010-05-21 19:30:41 +02:00
jbd2 Merge branch 'master' into for-2.6.35 2010-05-21 21:27:26 +02:00
jffs2 jffs2: constify xattr_handler 2010-05-21 18:31:20 -04:00
jfs jfs: replace inode uid,gid,mode init with helper 2010-05-21 18:31:23 -04:00
lockd include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
logfs logfs: replace inode uid,gid,mode initialization with helper function 2010-05-21 18:31:27 -04:00
minix minix: replace inode uid,gid,mode init with helper 2010-05-21 18:31:24 -04:00
ncpfs ncpfs: BKL ioctl pushdown 2010-05-17 05:27:42 +02:00
nfs kernel-wide: replace USHORT_MAX, SHORT_MAX and SHORT_MIN with USHRT_MAX, SHRT_MAX and SHRT_MIN 2010-05-25 08:07:02 -07:00
nfs_common include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
nfsd kernel-wide: replace USHORT_MAX, SHORT_MAX and SHORT_MIN with USHRT_MAX, SHRT_MAX and SHRT_MIN 2010-05-25 08:07:02 -07:00
nilfs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2010-05-21 19:37:45 -07:00
nls
notify Saner locking around deactivate_super() 2010-05-21 18:31:14 -04:00
ntfs ntfs: use add_to_page_cache_lru() 2010-05-25 08:07:03 -07:00
ocfs2 kernel-wide: replace USHORT_MAX, SHORT_MAX and SHORT_MIN with USHRT_MAX, SHRT_MAX and SHRT_MIN 2010-05-25 08:07:02 -07:00
omfs omfs: replace inode uid,gid,mode initialization with helper function 2010-05-21 18:31:25 -04:00
openpromfs
partitions fs: ldm: don't use own implementation of hex_to_bin() 2010-05-25 08:07:06 -07:00
proc kcore: add _text to KCORE_TEXT 2010-05-27 09:12:47 -07:00
qnx4 fs/qnx4: decrement sizeof size in strncmp 2010-02-04 11:55:46 +01:00
quota new helper: iterate_supers() 2010-05-21 18:31:16 -04:00
ramfs ramfs: replace inode uid,gid,mode initialization with helper function 2010-05-21 18:31:26 -04:00
reiserfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2010-05-21 19:37:45 -07:00
romfs fix leak in romfs_fill_super() 2010-01-26 22:22:26 -05:00
smbfs smbfs: remove duplicated #include 2010-05-25 08:07:07 -07:00
squashfs squashfs: fix name reading in squashfs_xattr_get 2010-05-23 08:27:42 +01:00
sysfs sysfs: add struct file* to bin_attr callbacks 2010-05-21 09:37:31 -07:00
sysv sysv: replace inode uid,gid,mode initialization with helper function 2010-05-21 18:31:26 -04:00
ubifs ubifs: replace inode uid,gid,mode initialization with helper function 2010-05-21 18:31:26 -04:00
udf udf: replace inode uid,gid,mode init with helper 2010-05-21 18:31:27 -04:00
ufs ufs: permit mounting of BorderWare filesystems 2010-05-27 09:12:43 -07:00
xfs Merge branch 'delayed-logging-for-2.6.35' into for-linus 2010-05-24 11:57:36 -05:00
aio.c
anon_inodes.c anon_inode: set S_IFREG on the anon_inode 2010-05-21 18:31:20 -04:00
attr.c fs: use rlimit helpers 2010-03-06 11:26:29 -08:00
bad_inode.c
binfmt_aout.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
binfmt_elf_fdpic.c Remove redundant check for CONFIG_MMU 2010-04-27 09:01:26 -07:00
binfmt_elf.c coredump: pass mm->flags as a coredump parameter for consistency 2010-03-06 11:26:46 -08:00
binfmt_em86.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
binfmt_flat.c uclinux: error message when FLAT reloc symbol is invalid, v2 2010-04-21 13:28:49 +10:00
binfmt_misc.c
binfmt_script.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
binfmt_som.c Split 'flush_old_exec' into two functions 2010-01-29 08:22:01 -08:00
bio-integrity.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
bio.c Merge branch 'master' into for-linus 2010-03-19 08:05:10 +01:00
block_dev.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2010-05-21 19:37:45 -07:00
buffer.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2010-05-21 19:37:45 -07:00
char_dev.c
compat_binfmt_elf.c elf coredump: replace ELF_CORE_EXTRA_* macros by functions 2010-03-06 11:26:45 -08:00
compat_ioctl.c pktcdvd: improve BKL and compat_ioctl.c usage 2010-04-29 08:44:37 -07:00
compat.c revert "procfs: provide stack information for threads" and its fixup commits 2010-05-11 17:33:41 -07:00
dcache.c fix prune_dcache()/umount() race 2010-05-21 18:31:16 -04:00
dcookies.c
direct-io.c
drop_caches.c new helper: iterate_supers() 2010-05-21 18:31:16 -04:00
eventfd.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
eventpoll.c sched, wait: Use wrapper functions 2010-05-11 17:43:58 +02:00
exec.c exit: avoid sig->count in de_thread/__exit_signal synchronization 2010-05-27 09:12:46 -07:00
fcntl.c Merge branch 'master' into for-2.6.35 2010-05-21 21:27:26 +02:00
fifo.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
file_table.c vfs: take f_lock on modifying f_mode after open time 2010-03-06 11:26:25 -08:00
file.c fs: use rlimit helpers 2010-03-06 11:26:29 -08:00
filesystems.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
fs_struct.c
fs-writeback.c fs-writeback: check sync bit earlier in inode_wait_for_writeback 2010-05-25 08:07:00 -07:00
generic_acl.c fs: xattr_handler table should be const 2010-05-21 18:31:18 -04:00
inode.c vfs: Add inode uid,gid,mode init helper 2010-05-21 18:31:22 -04:00
internal.h Bury __put_super_and_need_restart() 2010-05-21 18:31:16 -04:00
ioctl.c Introduce freeze_super and thaw_super for the fsfreeze ioctl 2010-05-21 18:31:18 -04:00
ioprio.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
Kconfig Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2010-03-19 09:43:06 -07:00
Kconfig.binfmt
libfs.c FS / libfs: Implement simple_write_to_buffer 2010-05-10 23:08:17 +02:00
locks.c Merge branch 'for-next' into for-linus 2010-03-08 16:55:37 +01:00
Makefile Take statfs variants to fs/statfs.c 2010-05-21 18:31:17 -04:00
mbcache.c
mpage.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
namei.c namei.c : update mnt when it needed 2010-05-21 18:31:22 -04:00
namespace.c Merge branch 'next' into for-linus 2010-05-18 08:57:00 +10:00
nfsctl.c Switch may_open() and break_lease() to passing O_... 2010-03-03 13:00:21 -05:00
no-block.c
open.c Take statfs variants to fs/statfs.c 2010-05-21 18:31:17 -04:00
pipe.c pipe: set lower and upper limit on max pages in the pipe page array 2010-05-21 21:12:52 +02:00
pnode.c Kill CL_PROPAGATION, sanitize fs/pnode.c:get_source() 2010-03-03 13:00:22 -05:00
pnode.h VFS: Clean up shared mount flag propagation 2010-03-03 14:07:55 -05:00
posix_acl.c
read_write.c do_sync_read/write() should set kiocb.ki_nbytes to be consistent 2010-03-24 16:43:29 -07:00
read_write.h
readdir.c
select.c Add generic sys_old_select() 2010-03-12 15:52:32 -08:00
seq_file.c seq_file: fix new kernel-doc warnings 2010-03-07 15:48:26 -08:00
signalfd.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
splice.c pipe: add support for shrinking and growing pipes 2010-05-21 21:12:40 +02:00
stack.c
stat.c
statfs.c Take statfs variants to fs/statfs.c 2010-05-21 18:31:17 -04:00
super.c vfs: add lockdep annotation to s_vfs_rename_key for ecryptfs 2010-05-21 18:31:22 -04:00
sync.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2010-05-21 19:37:45 -07:00
timerfd.c fs/timerfd.c: make use of wait_event_interruptible_locked_irq() 2010-05-20 13:21:42 -07:00
utimes.c
xattr_acl.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
xattr.c fs: xattr_handler table should be const 2010-05-21 18:31:18 -04:00