On 04.10.2016 22:17, Andrey Korolyov wrote: >> I'm super puzzled right now :-( >> > > There are three strawman` ideas out of head, down by a level of > naiveness increase: > - disk controller corrupts DMA chunks themselves, could be tested > against usb stick/sd card with same fs or by switching disk controller > to a legacy mode if possible, but cascading failure shown previously > should be rather unusual for this, I'll check out if this is possible somehow tomorrow. > - SMP could be partially broken in such manner that it would cause > overlapped accesses under certain conditions, may be checked with > 'nosmp', Unfortunately not: CC [M] drivers/infiniband/core/multicast.o CC [M] drivers/infiniband/core/mad.o drivers/infiniband/core/mad.c: In function ‘ib_mad_port_close’: drivers/infiniband/core/mad.c:3252:1: internal compiler error: Bus error } ^ nuc [~]: cat /proc/cmdline BOOT_IMAGE=/vmlinuz-4.8.0 root=UUID=f6a792b3-3027-4293-a118-f0df1de9b25c ro ip=:::::eno1:dhcp nosmp > - disk accesses and corresponding power spikes are causing partial > undervoltage condition somewhere where bits are relatively freely > flipping on paths without parity checking, though this could be > addressed only to an onboard power distributor, not to power source > itself. Huh that sounds like "defective hardware" to me, wouldn't it? Cheers and thank you for your help, Johannes -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>