On Sun, Aug 10, 2014 at 3:59 PM, Sebastian Andrzej Siewior <[email protected]> wrote: > Package: babeltrace > Version: 1.2.2-2 > Severity: wishlist > > I've been looking at the sparc issue and this is just a tracker bug. > One patch that helps passing half the testsuite is cae67efbd9 ("Fix: > Align buffers from objstack_alloc on sizeof(void *)") [0]. > I would suggest to use an alignment of 8 even on 32bit architectures. > The 4 additional bytes shouldn't matter and the Sparc FPU provides > double support which have a size of 8 bytes and so probably require an > aligment of 8 even on 32bit (the test suite didn't complain here). > Jérémie? >
It seems you don't have the following patch applied: commit 6a0b6cd5133db9e3c72914d4e5dd7fc792360934 Author: Mathieu Desnoyers <[email protected]> Date: Wed Jul 16 10:58:48 2014 -0400 Fix: don't perform unaligned integer read/writes Signed-off-by: Mathieu Desnoyers <[email protected]> I may be misunderstanding here, but we don't read floats directly in a trace. We basically use the ctf_integer_read functions, as you can see in _ctf_float_copy() in formats/ctf/types/floats.c That patch should ensure the accesses are always aligned (see the use of memcpy). Have you spotted a place where an unaligned float access is performed? > And the second bug I stumbled on is in test_ctf_writer: > |… > |ok 75 - Flush trace stream with one event > |ok 76 - Add a new event class to a stream class after writing an event > |ok 77 - Append 100 000 events to a stream > | > |Program received signal SIGSEGV, Segmentation fault. > |0xf7f6f778 in ctf_integer_write (ppos=0x70022328, definition=<optimized > out>) at integer.c:325 > |325 > bt_bitfield_write_be(mmap_align_addr(pos->base_mma) + > |(gdb) bt > |#0 0xf7f6f778 in ctf_integer_write (ppos=0x70022328, definition=<optimized > out>) at integer.c:325 > |#1 0xf7f88014 in bt_ctf_field_integer_serialize (field=0x700cd928, > pos=0x70022328) at event-fields.c:1065 > |#2 0xf7f88c88 in bt_ctf_field_serialize (field=0x700cd928, pos=0x70022328) > at event-fields.c:660 > |#3 0xf7f88f10 in bt_ctf_field_structure_serialize (field=0x700cd8c8, > pos=0x70022328) at event-fields.c:1143 > |#4 0xf7f88c88 in bt_ctf_field_serialize (field=0x700cd8c8, pos=0x70022328) > at event-fields.c:660 > |#5 0xf7f857bc in bt_ctf_stream_flush (stream=0x70022310) at stream.c:458 > |#6 0x7000577c in packet_resize_test (stream_class=<optimized out>, > stream=0x70022310, clock=0x70022108) at test_ctf_writer.c:698 > |#7 0x70002750 in main (argc=<optimized out>, argv=0xffffd6f4) at > test_ctf_writer.c:818 > | > |=> 0xf7f6f778 <+600>: ldub [ %l3 + %l1 ], %g4 > | > |l1 0x10002 65538 > |l3 0xf7bb4000 -138723328 > > and _bt_bitfield_write_le() had __ptr = 0xf7bb4000 and this_unit = 65538 > > |(gdb) print *((struct ctf_stream_pos *)ppos)->base_mma > |$3 = {page_aligned_addr = 0xf7bb4000, page_aligned_length = 131072, addr = > 0xf7bb4000, length = 131072} > > So it looks like it tried to load a byte from 0xf7bb4000 + 0x10002 and > this segfaulted. The mapping should be 131072 bytes in size it should > fit. This is confirmed by proc, too > |f7bb0000-f7bd0000 -w-s 00010000 fe:02 262357 > /tmp/ctfwriter_5uYQD4/test_stream_0 > |Size: 128 kB > > So everything looks legal… > Thanks for looking into this! Any idea what could cause this to fail? Jérémie > [0] > http://git.efficios.com/?p=babeltrace.git;a=commitdiff;h=cae67efbd9ddf2cee6bbefec076dc8933ababc43 > > Sebastian -- Jérémie Galarneau EfficiOS Inc. http://www.efficios.com -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
