Re: Suspend on Dell D420

From: Steinar H. Gunderson
Date: Sat Aug 05 2006 - 04:25:46 EST

On Sat, Aug 05, 2006 at 01:26:56AM +0200, Rafael J. Wysocki wrote:
> Because the non-boot CPUs are taken off early, before anything else, and the
> system is effectively non-SMP during the entire suspend-resume cycle
> (well, almost). If SMP-related things go wrong during the suspend, CPU
> hotplug is the first suspect. ;-)

Well, it seems to work fine during the suspend phase, at least, and it also
seems to work well during normal use:

fugl:~# echo 0 > /sys/devices/system/cpu/cpu1/online
fugl:~# echo 1 > /sys/devices/system/cpu/cpu1/online

FWIW, there is an error in dmesg afterwards, though:

CPU 1 is now offline
SMP alternatives: switching to UP code
SMP alternatives: switching to SMP code
Booting processor 1/1 eip 3000
Initializing CPU#1
Calibrating delay using timer specific routine.. 2394.85 BogoMIPS (lpj=4789709)
CPU: After generic identify, caps: bfe9fbff 00100000 00000000 00000000 0000c1a9 00000000 00000000
CPU: After vendor identify, caps: bfe9fbff 00100000 00000000 00000000 0000c1a9 00000000 00000000
monitor/mwait feature present.
CPU: L1 I cache: 32K, L1 D cache: 32K
CPU: L2 cache: 2048K
CPU: Physical Processor ID: 0
CPU: Processor Core ID: 1
CPU: After all inits, caps: bfe9fbff 00100000 00000000 00000140 0000c1a9 00000000 00000000
Intel machine check architecture supported.
Intel machine check reporting enabled on CPU#1.
CPU1: Intel Genuine Intel(R) CPU U2500 @ 1.20GHz stepping 08
APIC error on CPU1: 00(40)

No idea whether it's related. FWIW, resume didn't work with maxcpus=1 on boot
either, so I'm not really sure how related it is.

/* Steinar */
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at