Skip to content

Commit

Permalink
xen/smp: Warn user why they keel over - nosmp or noapic and what to u…
Browse files Browse the repository at this point in the history
…se instead.

We have hit a couple of customer bugs where they would like to
use those parameters to run an UP kernel - but both of those
options turn of important sources of interrupt information so
we end up not being able to boot. The correct way is to
pass in 'dom0_max_vcpus=1' on the Xen hypervisor line and
the kernel will patch itself to be a UP kernel.

Fixes bug: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=637308

CC: stable@kernel.org
Acked-by: Ian Campbell <Ian.Campbell@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
  • Loading branch information
Konrad Rzeszutek Wilk committed Sep 1, 2011
1 parent d198d49 commit ed467e6
Showing 1 changed file with 10 additions and 0 deletions.
10 changes: 10 additions & 0 deletions arch/x86/xen/smp.c
Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,7 @@
#include <xen/page.h>
#include <xen/events.h>

#include <xen/hvc-console.h>
#include "xen-ops.h"
#include "mmu.h"

Expand Down Expand Up @@ -207,6 +208,15 @@ static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
unsigned cpu;
unsigned int i;

if (skip_ioapic_setup) {
char *m = (max_cpus == 0) ?
"The nosmp parameter is incompatible with Xen; " \
"use Xen dom0_max_vcpus=1 parameter" :
"The noapic parameter is incompatible with Xen";

xen_raw_printk(m);
panic(m);
}
xen_init_lock_cpu(0);

smp_store_cpu_info(0);
Expand Down

0 comments on commit ed467e6

Please sign in to comment.