Hi, I've got a fileserver that runs Centos 5.2. It's been stable otherwise stable for maybe a year or more, and now it's crashed three times since Saturday. The first two times the computer was completely unresponsive, and there was nothing on the console, and nothing in the logs. I was beginning to suspect hardware, (esp. RAM, PSU, or maybe a failed fan) Last night it locked up again, but this time there was something in / var/log/messages. (see below) So far my searches indicate that increasing to 8K kernel stacks would fix this. The server has a couple 3ware SATA RAID cards, and I'm running xfs. The server does nightly disk to disk backups of a few dozen workstations. The server does always seem to crash overnight. If the problem really is in the kernel stack size, it's odd that it just started all of a sudden. I thought I'd post here before I looked into compiling a new kernel with 8K stacks. Thanks for any advice! --Peter 2.6.18-53.1.21.el5 #1 SMP Tue May 20 09:34:18 EDT 2008 i686 i686 i386 GNU/Linux Jan 14 03:06:21 fs2 kernel: do_IRQ: stack overflow: 464 Jan 14 03:06:21 fs2 kernel: [<c04073bd>] do_IRQ+0x5c/0xae Jan 14 03:06:21 fs2 kernel: BUG: unable to handle kernel paging request at virtual address fc7ff0aa Jan 14 03:06:21 fs2 kernel: printing eip: Jan 14 03:06:21 fs2 kernel: c0606da4 Jan 14 03:06:21 fs2 kernel: *pde = 00000000 Jan 14 03:06:21 fs2 kernel: BUG: unable to handle kernel paging request at virtual address fc7ff226 Jan 14 03:06:21 fs2 kernel: printing eip: Jan 14 03:06:21 fs2 kernel: c060704e Jan 14 03:06:21 fs2 kernel: *pde = 00000000 ----clip for repeating info------ Jan 14 03:06:21 fs2 kernel: BUG: unable to handle kernel paging request at virtual address fc7ff226 Jan 14 03:06:21 fs2 kernel: printing eip: Jan 14 03:06:21 fs2 kernel: c060704e Jan 14 03:06:21 fs2 kernel: *pde = 00000000 Jan 14 03:06:21 fs2 kernel: Oops: 0002 [#1] Jan 14 03:06:21 fs2 kernel: SMP Jan 14 03:06:21 fs2 kernel: last sysfs file: /devices/pci0000:00/0000:00:1e.0/0000:04:04.0/irq Jan 14 03:06:21 fs2 kernel: Modules linked in: ipv6 autofs4 hidp rfcomm l2cap bluetooth sunrpc xfs(U) dm_mul tipath video sbs backlight i2c_ec button battery asus_acpi ac lp i2c_i801 e7xxx_edac floppy edac_mc i2c_core ide_cd serio_raw e100 parport_pc cdrom e1000 mii parport intel_rng sg pcspkr dm_snapshot dm_zero dm_mirror dm_mod ata_piix libata 3w_9xxx sd_mod scsi_mod ext3 jbd ehci_hcd ohci_hcd uhci_hcd Jan 14 03:06:21 fs2 kernel: CPU: -1065923552 Jan 14 03:06:21 fs2 kernel: EIP: 0060:[<c060704e>] Not tainted VLI Jan 14 03:06:21 fs2 kernel: EFLAGS: 00010046 (2.6.18-53.1.21.el5 #1) Jan 14 03:06:21 fs2 kernel: EIP is at do_page_fault+0x3c5/0x4b8 Jan 14 03:06:21 fs2 kernel: eax: 00000013 ebx: 00000000 ecx: c0626aae edx: 00006dbf Jan 14 03:06:21 fs2 kernel: esi: fc7ff226 edi: fc7ff026 ebp: 00000002 esp: f0b69170 Jan 14 03:06:21 fs2 kernel: ds: 007b es: 007b ss: 0068 Jan 14 03:06:21 fs2 kernel: BUG: unable to handle kernel paging request at virtual address 000100ca Jan 14 03:06:21 fs2 kernel: printing eip: Jan 14 03:06:21 fs2 kernel: c0606da4 Jan 14 03:06:21 fs2 kernel: *pde = 707f0067 Jan 14 03:06:21 fs2 kernel: BUG: unable to handle kernel paging request at virtual address 826ef258 Jan 14 03:06:21 fs2 kernel: printing eip: Jan 14 03:06:21 fs2 kernel: c041fa82 Jan 14 03:06:21 fs2 kernel: *pde = 00000000