Eric and all, That is clearly a limitation in romio, and this is being tracked at https://trac.mpich.org/projects/mpich/ticket/2212
in the mean time, what we can do in OpenMPI is update mca_io_romio_file_open() and fails with a user friendly error message if strlen(filename) is larger that 225. Cheers, Gilles On 2014/12/16 12:43, Gilles Gouaillardet wrote: > Eric, > > thanks for the simple test program. > > i think i see what is going wrong and i will make some changes to avoid > the memory overflow. > > that being said, there is a hard coded limit of 256 characters, and your > path is bigger than 300 characters. > bottom line, and even if there is no more memory overflow, that cannot > work as expected. > > i will report this to the mpich folks, since romio is currently imported > from mpich. > > Cheers, > > Gilles > > On 2014/12/16 0:16, Eric Chamberland wrote: >> Hi Gilles, >> >> just created a very simple test case! >> >> with this setup, you will see the bug with valgrind: >> >> export >> too_long=./this/is/a_very/long/path/that/contains/a/not/so/long/filename/but/trying/to/collectively/mpi_file_open/it/you/will/have/a/memory/corruption/resulting/of/invalide/writing/or/reading/past/the/end/of/one/or/some/hidden/strings/in/mpio/Simple/user/would/like/to/have/the/parameter/checked/and/an/error/returned/or/this/limit/removed >> >> mpicc -o bug_MPI_File_open_path_too_long >> bug_MPI_File_open_path_too_long.c >> >> mkdir -p $too_long >> echo "header of a text file" > $too_long/toto.txt >> >> mpirun -np 2 valgrind ./bug_MPI_File_open_path_too_long >> $too_long/toto.txt >> >> and watch the errors! >> >> unfortunately, the memory corruptions here doesn't seem to segfault >> this simple test case, but in my case, it is fatal and with valgrind, >> it is reported... >> >> OpenMPI 1.6.5, 1.8.3rc3 are affected >> >> MPICH-3.1.3 also have the error! >> >> thanks, >> >> Eric >> > _______________________________________________ > users mailing list > us...@open-mpi.org > Subscription: http://www.open-mpi.org/mailman/listinfo.cgi/users > Link to this post: > http://www.open-mpi.org/community/lists/users/2014/12/26005.php
