Srivatsa Vaddagiri <[email protected]> wrote:
>
> Well ..other arch-es need to have a similar check if they get around to
> implement physical hot-add (even if they allow offlining of all CPUs). This is
> required since a user can (by mistake maybe) try to bring up an already online
> CPU by writing a '1' to it's sysfs 'online' file. 'store_online'
> (drivers/base/cpu.c) unconditionally calls 'smp_prepare_cpu' w/o checking for
> this error condition. The check added in the patch catches such error
> conditions as well.
OK.. I guess we should fix those architectures while we're thinking about it.
> --- linux-2.6.16-rc6/arch/i386/kernel/smpboot.c~cpu_hp 2006-03-17 14:27:15.000000000 +0530
> +++ linux-2.6.16-rc6-root/arch/i386/kernel/smpboot.c 2006-03-17 14:38:50.000000000 +0530
> @@ -1029,6 +1029,16 @@ int __devinit smp_prepare_cpu(int cpu)
> int apicid, ret;
>
> lock_cpu_hotplug();
> +
> + /* Check if CPU is already online. This can happen if user tries to
> + * bringup an already online CPU or a previous offline attempt
> + * on this CPU has failed.
> + */
> + if (cpu_online(cpu)) {
> + ret = -EINVAL;
> + goto exit;
> + }
> +
How well tested is this? From my reading, this will cause
enable_nonboot_cpus() to panic. Is that intended?
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
