The call to memset will segfault because the offset for the first parameter is done twice. We are using pointer math to do the calculation. The first time is when calculating oldsize, the size of i2gseg_t is accounted for. oldsize = (numsegs - SEGPERHNK) * sizeof(i2gseg_t); Then in the call to memset, oldsize is again multiplied by the size of i2gmap_t. memset(inomap.i2gmap + oldsize, ...) i2gmap holds the used inodes in each chunk. When there are 2^31 chunk entries, it could describe 2^31 (1 inode/chunk)- 2^40 (64 inodes/chunk). With 100s of millions of inodes there are enough entries to wrap the 32 bit variable oldsize. Switching to use array index notation instead of calculating the pointer address twice ;) would resolve this issue. The unneeded local variable oldsize can be removed as well. --- dump/inomap.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) Index: b/dump/inomap.c =================================================================== --- a/dump/inomap.c +++ b/dump/inomap.c @@ -1125,8 +1125,7 @@ cb_add_inogrp( void *arg1, intgen_t fsfd lastsegp->segoff = 0; if (lastsegp->hnkoff == inomap.hnkmaplen) { - intgen_t numsegs; - intgen_t oldsize; + int64_t numsegs; inomap.hnkmaplen++; inomap.hnkmap = (hnk_t *) @@ -1140,10 +1139,7 @@ cb_add_inogrp( void *arg1, intgen_t fsfd return -1; /* zero the new portion of the i2gmap */ - oldsize = (numsegs - SEGPERHNK) * sizeof(i2gseg_t); - - memset(inomap.i2gmap + oldsize, - 0, + memset(&inomap.i2gmap[numsegs - SEGPERHNK], 0, SEGPERHNK * sizeof(i2gseg_t)); } _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs