Revision 6d5b5acca9e566515ef3f1ed617e7295c4f94345 authored by Heiko Carstens on 09 March 2009, 12:31:59 UTC, committed by Linus Torvalds on 09 March 2009, 15:13:35 UTC
Frans Pop reported the crash below when running an s390 kernel under Hercules: Kernel BUG at 000738b4 verbose debug info unavailable! fixpoint divide exception: 0009 #1! SMP Modules linked in: nfs lockd nfs_acl sunrpc ctcm fsm tape_34xx cu3088 tape ccwgroup tape_class ext3 jbd mbcache dm_mirror dm_log dm_snapshot dm_mod dasd_eckd_mod dasd_mod CPU: 0 Not tainted 2.6.27.19 #13 Process awk (pid: 2069, task: 0f9ed9b8, ksp: 0f4f7d18) Krnl PSW : 070c1000 800738b4 (acct_update_integrals+0x4c/0x118) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:1 PM:0 Krnl GPRS: 00000000 000007d0 7fffffff fffff830 00000000 ffffffff 00000002 0f9ed9b8 00000000 00008ca0 00000000 0f9ed9b8 0f9edda4 8007386e 0f4f7ec8 0f4f7e98 Krnl Code: 800738aa: a71807d0 lhi %r1,2000 800738ae: 8c200001 srdl %r2,1 800738b2: 1d21 dr %r2,%r1 >800738b4: 5810d10e l %r1,270(%r13) 800738b8: 1823 lr %r2,%r3 800738ba: 4130f060 la %r3,96(%r15) 800738be: 0de1 basr %r14,%r1 800738c0: 5800f060 l %r0,96(%r15) Call Trace: ( <000000000004fdea>! blocking_notifier_call_chain+0x1e/0x2c) <0000000000038502>! do_exit+0x106/0x7c0 <0000000000038c36>! do_group_exit+0x7a/0xb4 <0000000000038c8e>! SyS_exit_group+0x1e/0x30 <0000000000021c28>! sysc_do_restart+0x12/0x16 <0000000077e7e924>! 0x77e7e924 Reason for this is that cpu time accounting usually only happens from interrupt context, but acct_update_integrals gets also called from process context with interrupts enabled. So in acct_update_integrals we may end up with the following scenario: Between reading tsk->stime/tsk->utime and tsk->acct_timexpd an interrupt happens which updates accouting values. This causes acct_timexpd to be greater than the former stime + utime. The subsequent calculation of dtime = cputime_sub(time, tsk->acct_timexpd); will be negative and the division performed by cputime_to_jiffies(dtime) will generate an exception since the result won't fit into a 32 bit register. In order to fix this just always disable interrupts while accessing any of the accounting values. Reported by: Frans Pop <elendil@planet.nl> Tested by: Frans Pop <elendil@planet.nl> Cc: stable@kernel.org Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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lzo | ||
reed_solomon | ||
zlib_deflate | ||
zlib_inflate | ||
.gitignore | -rw-r--r-- | 51 bytes |
Kconfig | -rw-r--r-- | 3.6 KB |
Kconfig.debug | -rw-r--r-- | 30.7 KB |
Kconfig.kgdb | -rw-r--r-- | 1.8 KB |
Makefile | -rw-r--r-- | 2.9 KB |
argv_split.c | -rw-r--r-- | 1.8 KB |
audit.c | -rw-r--r-- | 1.2 KB |
bcd.c | -rw-r--r-- | 257 bytes |
bitmap.c | -rw-r--r-- | 30.5 KB |
bitrev.c | -rw-r--r-- | 2.1 KB |
bug.c | -rw-r--r-- | 4.6 KB |
bust_spinlocks.c | -rw-r--r-- | 636 bytes |
check_signature.c | -rw-r--r-- | 599 bytes |
cmdline.c | -rw-r--r-- | 3.6 KB |
cpumask.c | -rw-r--r-- | 4.3 KB |
crc-ccitt.c | -rw-r--r-- | 3.0 KB |
crc-itu-t.c | -rw-r--r-- | 2.8 KB |
crc-t10dif.c | -rw-r--r-- | 2.9 KB |
crc16.c | -rw-r--r-- | 2.8 KB |
crc32.c | -rw-r--r-- | 14.9 KB |
crc32defs.h | -rw-r--r-- | 1.0 KB |
crc7.c | -rw-r--r-- | 2.3 KB |
ctype.c | -rw-r--r-- | 1.3 KB |
debug_locks.c | -rw-r--r-- | 1.1 KB |
debugobjects.c | -rw-r--r-- | 21.3 KB |
dec_and_lock.c | -rw-r--r-- | 806 bytes |
devres.c | -rw-r--r-- | 7.7 KB |
div64.c | -rw-r--r-- | 2.3 KB |
dump_stack.c | -rw-r--r-- | 290 bytes |
dynamic_printk.c | -rw-r--r-- | 9.5 KB |
extable.c | -rw-r--r-- | 1.9 KB |
fault-inject.c | -rw-r--r-- | 7.9 KB |
find_last_bit.c | -rw-r--r-- | 1.1 KB |
find_next_bit.c | -rw-r--r-- | 6.4 KB |
gen_crc32table.c | -rw-r--r-- | 1.8 KB |
genalloc.c | -rw-r--r-- | 5.3 KB |
halfmd4.c | -rw-r--r-- | 2.0 KB |
hexdump.c | -rw-r--r-- | 6.1 KB |
hweight.c | -rw-r--r-- | 1.6 KB |
idr.c | -rw-r--r-- | 20.5 KB |
inflate.c | -rw-r--r-- | 38.6 KB |
int_sqrt.c | -rw-r--r-- | 533 bytes |
iomap.c | -rw-r--r-- | 7.4 KB |
iomap_copy.c | -rw-r--r-- | 2.1 KB |
iommu-helper.c | -rw-r--r-- | 2.0 KB |
ioremap.c | -rw-r--r-- | 2.1 KB |
irq_regs.c | -rw-r--r-- | 578 bytes |
is_single_threaded.c | -rw-r--r-- | 1.2 KB |
kasprintf.c | -rw-r--r-- | 680 bytes |
kernel_lock.c | -rw-r--r-- | 2.9 KB |
klist.c | -rw-r--r-- | 9.3 KB |
kobject.c | -rw-r--r-- | 20.7 KB |
kobject_uevent.c | -rw-r--r-- | 8.0 KB |
kref.c | -rw-r--r-- | 1.9 KB |
libcrc32c.c | -rw-r--r-- | 2.1 KB |
list_debug.c | -rw-r--r-- | 1.5 KB |
lmb.c | -rw-r--r-- | 11.6 KB |
locking-selftest-hardirq.h | -rw-r--r-- | 207 bytes |
locking-selftest-mutex.h | -rw-r--r-- | 120 bytes |
locking-selftest-rlock-hardirq.h | -rw-r--r-- | 74 bytes |
locking-selftest-rlock-softirq.h | -rw-r--r-- | 74 bytes |
locking-selftest-rlock.h | -rw-r--r-- | 158 bytes |
locking-selftest-rsem.h | -rw-r--r-- | 163 bytes |
locking-selftest-softirq.h | -rw-r--r-- | 207 bytes |
locking-selftest-spin-hardirq.h | -rw-r--r-- | 73 bytes |
locking-selftest-spin-softirq.h | -rw-r--r-- | 73 bytes |
locking-selftest-spin.h | -rw-r--r-- | 118 bytes |
locking-selftest-wlock-hardirq.h | -rw-r--r-- | 74 bytes |
locking-selftest-wlock-softirq.h | -rw-r--r-- | 74 bytes |
locking-selftest-wlock.h | -rw-r--r-- | 158 bytes |
locking-selftest-wsem.h | -rw-r--r-- | 163 bytes |
locking-selftest.c | -rw-r--r-- | 28.6 KB |
parser.c | -rw-r--r-- | 6.0 KB |
percpu_counter.c | -rw-r--r-- | 3.2 KB |
plist.c | -rw-r--r-- | 2.8 KB |
prio_heap.c | -rw-r--r-- | 1.4 KB |
prio_tree.c | -rw-r--r-- | 12.2 KB |
proportions.c | -rw-r--r-- | 9.3 KB |
radix-tree.c | -rw-r--r-- | 31.0 KB |
random32.c | -rw-r--r-- | 3.8 KB |
ratelimit.c | -rw-r--r-- | 1.3 KB |
rbtree.c | -rw-r--r-- | 8.7 KB |
reciprocal_div.c | -rw-r--r-- | 159 bytes |
rwsem-spinlock.c | -rw-r--r-- | 6.8 KB |
rwsem.c | -rw-r--r-- | 6.4 KB |
scatterlist.c | -rw-r--r-- | 11.8 KB |
sha1.c | -rw-r--r-- | 2.4 KB |
show_mem.c | -rw-r--r-- | 1.4 KB |
smp_processor_id.c | -rw-r--r-- | 1.1 KB |
sort.c | -rw-r--r-- | 2.5 KB |
spinlock_debug.c | -rw-r--r-- | 6.8 KB |
string.c | -rw-r--r-- | 13.6 KB |
string_helpers.c | -rw-r--r-- | 1.7 KB |
swiotlb.c | -rw-r--r-- | 25.6 KB |
syscall.c | -rw-r--r-- | 2.4 KB |
textsearch.c | -rw-r--r-- | 9.5 KB |
ts_bm.c | -rw-r--r-- | 5.3 KB |
ts_fsm.c | -rw-r--r-- | 10.6 KB |
ts_kmp.c | -rw-r--r-- | 4.3 KB |
vsprintf.c | -rw-r--r-- | 31.4 KB |
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