Hi, Thanks to Alex's fixes for PCI segment support, we could boot 2.5.67 kernel on Tiger. But a strange thing is happening. Only cpu0 & 1 are getting timer interrupts and cpu 2 & 3 aren't. This problem is reproducible and we see this phenomenon after every boot. It seems that these cpus stop receiving timer interrupts after a very short while. Has anyone seen this? I attached the config. I compiled the kernel with gcc version 3.2.3 20030407 (Debian prerelease) and binutils 2.13.90.0.18 20030121 Debian GNU/Linux. [root@tiger root]# cat /proc/stat cpu 3634837 0 14291 9632002 32284 cpu0 1816379 0 10110 4809692 20522 cpu1 1818458 0 4181 4822257 11762 cpu2 0 0 0 27 0 cpu3 0 0 0 26 0 intr 13335591 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 15 0 2 0 0 0 0 0 0 0 2 299 9 0 0 0 236 12415 0 0 0 0 8692 42 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 13313475 0 0 0 0 0 0 0 0 0 0 0 0 0 0 399 0 ctxt 88342 btime 1050389895 processes 1921 procs_running 5 procs_blocked 0 [root@tiger root]# cat /proc/interrupts CPU0 CPU1 CPU2 CPU3 30: 0 0 0 0 IO-SAPIC-level cpe_hndlr 31: 0 0 0 0 LSAPIC cmc_hndlr 34: 1 0 14 0 IO-SAPIC-edge ide0 39: 0 0 0 0 IO-SAPIC-level acpi 45: 0 0 299 0 IO-SAPIC-edge serial 49: 0 0 0 0 IO-SAPIC-level uhci-hcd 50: 0 0 236 0 IO-SAPIC-level uhci-hcd 51: 0 0 12510 0 IO-SAPIC-level eth0 56: 0 0 8694 0 IO-SAPIC-level ioc0 57: 0 0 42 0 IO-SAPIC-level ioc1 232: 0 0 0 0 LSAPIC mca_rdzv 238: 1 1 1 1 LSAPIC perfmon 239: 6693336 6693231 27 26 LSAPIC timer 240: 0 0 0 0 LSAPIC mca_wkup 254: 8 128 133 133 LSAPIC IPI NMI: 0 0 0 0 ERR: 0 Thanks, --- Takayoshi Kochi