This one is slightly different than the other item thread in this list. This panic occurred when my weekly cron job fired to "svn up" my STABLE system to r255294. I did not find a core file. The panic and reboot happened in the middle of the night and I just noticed it this morning when I went to perform a build world. My system is also an AMD64. Sep 28 05:47:48 host kernel: panic: vm_page_insert: offset already allocated Sep 28 05:47:48 host kernel: cpuid = 1 Sep 28 05:47:48 host kernel: KDB: stack backtrace: Sep 28 05:47:48 host kernel: #0 0xffffffff80489c66 at kdb_backtrace+0x66 Sep 28 05:47:48 host kernel: #1 0xffffffff804511ce at panic+0x1ce Sep 28 05:47:48 host kernel: #2 0xffffffff80639f65 at vm_page_insert+0x185 Sep 28 05:47:48 host kernel: #3 0xffffffff8063b58e at vm_page_alloc+0x27e Sep 28 05:47:48 host kernel: #4 0xffffffff8063bb66 at vm_page_grab+0x86 Sep 28 05:47:48 host kernel: #5 0xffffffff804cf1eb at allocbuf+0x36b Sep 28 05:47:48 host kernel: #6 0xffffffff804d2e2c at getblk+0x60c Sep 28 05:47:48 host kernel: #7 0xffffffff804d33f0 at breadn_flags+0x40 Sep 28 05:47:48 host kernel: #8 0xffffffff805e42b2 at ffs_update+0x102 Sep 28 05:47:48 host kernel: #9 0xffffffff8060f1d3 at ufs_inactive+0x1a3 Sep 28 05:47:48 host kernel: #10 0xffffffff8069fbe8 at VOP_INACTIVE_APV+0x78 Sep 28 05:47:48 host kernel: #11 0xffffffff804e9836 at vinactive+0x86 Sep 28 05:47:48 host kernel: #12 0xffffffff804ed5c8 at vputx+0x2d8 Sep 28 05:47:48 host kernel: #13 0xffffffff804fb827 at vn_close+0xa7 Sep 28 05:47:48 host kernel: #14 0xffffffff804fb90d at vn_closefile+0x5d Sep 28 05:47:48 host kernel: #15 0xffffffff8040db63 at _fdrop+0x23 Sep 28 05:47:48 host kernel: #16 0xffffffff8040eebc at closef+0x4c -- Public Keys: PGP KeyID = 0x5F22FDC1 GnuPG KeyID = 0x620836CF