Explicitly truncate the second operand of do_div() to 32 bits to guard
against bogus code calling it with a 64-bit divisor.
[Thorsten]
After upgrading from 3.2 to 3.10, mounting a btrfs volume fails with:
btrfs: setting nodatacow, compression disabled
btrfs: enabling auto recovery
btrfs: disk space caching is enabled
*** ZERO DIVIDE *** FORMAT=2
Current process id is 722
BAD KERNEL TRAP: 00000000
Modules linked in: evdev mac_hid ext4 crc16 jbd2 mbcache btrfs xor lzo_compress zlib_deflate raid6_pq crc32c libcrc32c
PC: [<319535b2>] __btrfs_map_block+0x11c/0x119a [btrfs]
SR: 2000 SP: 30c1fab4 a2: 30f0faf0
d0: 00000000 d1: 00001000 d2: 00000000 d3: 00000000
d4: 00010000 d5: 00000000 a0: 3085c72c a1: 3085c72c
Process mount (pid: 722, task=30f0faf0)
Frame format=2 instr addr=319535ae
Stack from 30c1faec:
00000000 00000020 00000000 00001000 00000000 01401000 30253928 300ffc00
00a843ac 3026f640 00000000 00010000 0009e250 00d106c0 00011220 00000000
00001000 301c6830 0009e32a 000000ff 00000009 3085c72c 00000000 00000000
30c1fd14 00000000 00000020 00000000 30c1fd14 0009e26c 00000020 00000003
00000000 0009dd8a 300b0b6c 30253928 00a843ac 00001000 00000000 00000000
0000a008 3194e76a 30253928 00a843ac 00001000 00000000 00000000 00000002
Call Trace: [<00001000>] kernel_pg_dir+0x0/0x1000
[...]
Code: 222e ff74 2a2e ff5c 2c2e ff60 4c45 1402 <2d40> ff64 2d41 ff68 2205 4c2e 1800 ff68 4c04 0800 2041 d1c0 2206 4c2e 1400 ff68
[Geert]
As diagnosed by Andreas, fs/btrfs/volumes.c:__btrfs_map_block()
calls
do_div(stripe_nr, stripe_len);
with stripe_len u64, while do_div() assumes the divisor is a 32-bit number.
Due to the lack of truncation in the m68k-specific implementation of
do_div(), the division is performed using the upper 32-bit word of
stripe_len, which is zero.
This was introduced by commit 53b381b3abeb86f12787a6c40fee9b2f71edc23b
("Btrfs: RAID5 and RAID6"), which changed the divisor from
map->stripe_len (struct map_lookup.stripe_len is int) to a 64-bit temporary.
Reported-by: Thorsten Glaser <tg@debian.org>
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Tested-by: Thorsten Glaser <tg@debian.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org
Pull m68k updates from Geert Uytterhoeven. * 'for-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: m68k/q40: Enable PC parallel port in defconfig m68k/q40: Undefine insl/outsl before redefining them m68k/uaccess: Fix asm constraints for userspace access swim: Release memory region after incorrect return/goto m68k/irq: Vector ints need a valid interrupt handler m68k/math-emu: unsigned issue, 'unsigned long' will never be less than zero m68k: remove CONFIG_EARLY_PRINTK dependency on CONFIG_EMBEDDED, default to n m68k/sun3: remove inline marking of EXPORT_SYMBOL functions [SCSI] a3000: use module_platform_driver_probe() [SCSI] a4000t: use module_platform_driver_probe() m68k: Remove inline strcpy() and strcat() implementations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
To use the PC parallel port driver on Q40, we need non-standard versions of
the insl/outsl accessors. Make sure to undefine them first, to kill this
compiler warning:
In file included from drivers/parport/parport_pc.c:67:
arch/m68k/include/asm/parport.h:14:1: warning: "insl" redefined
In file included from arch/m68k/include/asm/io.h:4,
from include/linux/scatterlist.h:10,
from include/linux/dma-mapping.h:9,
from drivers/parport/parport_pc.c:54:
arch/m68k/include/asm/io_mm.h:370:1: warning: this is the location of the previous definition
In file included from drivers/parport/parport_pc.c:67:
arch/m68k/include/asm/parport.h:15:1: warning: "outsl" redefined
In file included from arch/m68k/include/asm/io.h:4,
from include/linux/scatterlist.h:10,
from include/linux/dma-mapping.h:9,
from drivers/parport/parport_pc.c:54:
arch/m68k/include/asm/io_mm.h:373:1: warning: this is the location of the previous definition
Reported-by: Thorsten Glaser <tg@debian.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
When compiling a MMU kernel with CPU_HAS_ADDRESS_SPACES=n (e.g. "MMU=y
allnoconfig": "echo CONFIG_MMU=y > allno.config && make KCONFIG_ALLCONFIG=1
allnoconfig"), we use plain "move" instead of "moves", and I got:
CC arch/m68k/lib/uaccess.o
{standard input}: Assembler messages:
{standard input}:47: Error: operands mismatch -- statement `move.b %a0,(%a1)' ignored
This happens because plain "move" doesn't support byte transfers between
memory and address registers, while "moves" does.
Fix the asm constraints for __generic_copy_from_user(),
__generic_copy_to_user(), and __clear_user() to only use data registers
when accessing userspace.
Also, relax the asm constraints for 16-bit userspace accesses in
__put_user() and __get_user(), as both "move" and "moves" do support
such transfers between memory and address registers.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Gcc may replace calls to standard string functions by open code and/or
calls to other standard string functions. If the replacement function is
not available out-of-line, link errors will happen.
To avoid this, the out-of-line versions were provided by
arch/m68k/lib/string.c, but they were usually not linked in anymore as
typically none of its symbols are referenced by built-in code.
However, if any module would need them, they would not be available.
Hence remove the inline strcpy() and strcat() implementations, remove
arch/m68k/lib/string.c, and let the generic string library code handle it.
Impact on a typical kernel build seems minimal or nonexistent:
- .text : 0x00001000 - 0x002aac74 (2728 KiB)
- .data : 0x002ada48 - 0x00392148 ( 914 KiB)
+ .text : 0x00001000 - 0x002aacf4 (2728 KiB)
+ .data : 0x002adac8 - 0x00392148 ( 914 KiB)
See also commit e00c73ee05dc38ecaccced55d4f5fc58b0b769f7 ("m68k: Remove
inline strlen() implementation").
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Pull m68knommu fix from Greg Ungerer: "A single fix for compilation breakage to many of the ColdFire CPU targets" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: m68k: only use local gpio_request_one if not using GPIOLIB
Compiling for targets that use the local gpio code (not GPIOLIB) fail to
compile with:
CC arch/m68k/platform/coldfire/device.o
In file included from include/linux/gpio.h:45:0,
from arch/m68k/platform/coldfire/device.c:15:
/home/gerg/new-wave.git/linux-3.x/arch/m68k/include/asm/gpio.h:89:19: error: static declaration of ‘gpio_request_one’ follows non-static declaration
include/asm-generic/gpio.h:195:12: note: previous declaration of ‘gpio_request_one’ was here
Fix by conditionally using the local gpio_request_one() function based on
!CONFIG_GPIOLIB.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Linux/M68K currently doesn't support robust futexes or PI mutexes.
The problem is that the futex code needs to perform certain ops
(cmpxchg, set, add, or, andn, xor) atomically on user-space
addresses, and M68K's lack of a futex.h causes those operations
to be unsupported and disabled.
This patch adds that support, but only for uniprocessor machines,
which is adequate for M68K. For UP it's enough to disable preemption
to ensure mutual exclusion (futexes don't need to care about other
hardware agents), and the mandatory pagefault_disable() does just that.
This patch is closely based on the one I co-wrote for UP ARM back
in August 2008. The main change is that this patch uses the C
get_user/put_user accessors instead of inline assembly code with
exception table fixups.
For non-MMU machines the new futex.h simply redirects to the generic
futex.h, so there is no functional change for them.
Tested on aranym with the glibc-2.17 test suite: no regressions, and
a number of mutex/condvar test cases went from failing to succeeding
(tst-mutexpi{5,5a,6,9}, tst-cond2[45], tst-robust[1-9], tst-robustpi[1-8]).
Also tested with glibc-2.18 HEAD and a local glibc patch to enable PI
mutexes: no regressions.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Acked-by: Andreas Schwab <schwab@linux-m68k.org>
[geert: Added removal of ""generic-y += futex.h"]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Pull misc fixes from David Woodhouse: "This is some miscellaneous cleanups that don't really belong anywhere else (or were ignored), that have been sitting in linux-next for some time. Two of them are fixes resulting from my audit of krealloc() usage that don't seem to have elicited any response when I posted them, and the other three are patches from Artem removing dead code." * tag 'for-linus-20130509' of git://git.infradead.org/~dwmw2/random-2.6: pcmcia: remove RPX board stuff m68k: remove rpxlite stuff pcmcia: remove Motorola MBX860 support params: Fix potential memory leak in add_sysfs_param() dell-laptop: Fix krealloc() misuse in parse_da_table()