linux/arch
Yinghai Lu 7de3d66b13 x86: Fix adjust_range_size_mask calling position
Commit

    8d57470d x86, mm: setup page table in top-down

causes a kernel panic while setting mem=2G.

     [mem 0x00000000-0x000fffff] page 4k
     [mem 0x7fe00000-0x7fffffff] page 1G
     [mem 0x7c000000-0x7fdfffff] page 1G
     [mem 0x00100000-0x001fffff] page 4k
     [mem 0x00200000-0x7bffffff] page 2M

for last entry is not what we want, we should have
     [mem 0x00200000-0x3fffffff] page 2M
     [mem 0x40000000-0x7bffffff] page 1G

Actually we merge the continuous ranges with same page size too early.
in this case, before merging we have
     [mem 0x00200000-0x3fffffff] page 2M
     [mem 0x40000000-0x7bffffff] page 2M
after merging them, will get
     [mem 0x00200000-0x7bffffff] page 2M
even we can use 1G page to map
     [mem 0x40000000-0x7bffffff]

that will cause problem, because we already map
     [mem 0x7fe00000-0x7fffffff] page 1G
     [mem 0x7c000000-0x7fdfffff] page 1G
with 1G page, aka [0x40000000-0x7fffffff] is mapped with 1G page already.
During phys_pud_init() for [0x40000000-0x7bffffff], it will not
reuse existing that pud page, and allocate new one then try to use
2M page to map it instead, as page_size_mask does not include
PG_LEVEL_1G. At end will have [7c000000-0x7fffffff] not mapped, loop
in phys_pmd_init stop mapping at 0x7bffffff.

That is right behavoir, it maps exact range with exact page size that
we ask, and we should explicitly call it to map [7c000000-0x7fffffff]
before or after mapping 0x40000000-0x7bffffff.
Anyway we need to make sure ranges' page_size_mask correct and consistent
after split_mem_range for each range.

Fix that by calling adjust_range_size_mask before merging range
with same page size.

-v2: update change log.
-v3: add more explanation why [7c000000-0x7fffffff] is not mapped, and
    it causes panic.

Bisected-by: "Xie, ChanglongX" <changlongx.xie@intel.com>
Bisected-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reported-and-tested-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1370015587-20835-1-git-send-email-yinghai@kernel.org
Cc: <stable@vger.kernel.org> v3.9
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-05-31 13:21:32 -07:00
..
alpha Removal of GENERIC_GPIO for v3.10 2013-05-09 09:59:16 -07:00
arc ARC: lazy dcache flush broke gdb in non-aliasing configs 2013-05-25 14:15:55 +05:30
arm Pin control fixes for v3.10: 2013-05-30 08:54:29 +09:00
arm64 arm64: debug: fix mdscr.ss check when enabling debug exceptions 2013-05-17 18:24:19 +01:00
avr32 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/egtvedt/linux-avr32 2013-05-22 18:06:57 -07:00
blackfin blackfin updates for Linux 3.10 2013-05-10 07:21:16 -07:00
c6x dump_stack: unify debug information printed by show_regs() 2013-04-30 17:04:02 -07:00
cris - Lots of cleanups from Artem, including deletion of some obsolete drivers 2013-05-09 10:15:46 -07:00
frv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-05-01 14:08:52 -07:00
h8300 We get rid of the general module prefix confusion with a binary config option, 2013-05-05 10:58:06 -07:00
hexagon Removal of GENERIC_GPIO for v3.10 2013-05-09 09:59:16 -07:00
ia64 Removal of GENERIC_GPIO for v3.10 2013-05-09 09:59:16 -07:00
m32r Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-05-01 14:08:52 -07:00
m68k m68k: Update defconfigs for v3.9 2013-05-28 10:22:06 +02:00
metag Removal of GENERIC_GPIO for v3.10 2013-05-09 09:59:16 -07:00
microblaze microblaze: Reversed logic in futex cmpxchg 2013-05-27 12:29:35 +02:00
mips USB fixes for 3.10-rc2 2013-05-23 09:23:32 -07:00
mn10300 MN10300: Need pci_iomap() and __pci_ioport_map() defining 2013-05-30 13:38:48 +09:00
openrisc Removal of GENERIC_GPIO for v3.10 2013-05-09 09:59:16 -07:00
parisc parisc: fix irq stack on UP and SMP 2013-05-24 23:29:01 +02:00
powerpc Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2013-05-24 08:57:38 -07:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2013-05-21 09:36:46 -07:00
score score: remove redundant kcore_list entries 2013-05-25 10:27:27 -07:00
sh Removal of GENERIC_GPIO for v3.10 2013-05-09 09:59:16 -07:00
sparc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2013-05-10 09:21:05 -07:00
tile Merge branch 'stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile 2013-05-09 14:34:58 -07:00
um Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-05-07 15:14:53 -07:00
unicore32 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2013-05-10 09:21:05 -07:00
x86 x86: Fix adjust_range_size_mask calling position 2013-05-31 13:21:32 -07:00
xtensa Xtensa patchset for v3.10-rc1 2013-05-09 14:38:16 -07:00
.gitignore
Kconfig Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-05-15 14:04:00 -07:00