diff options
Diffstat (limited to 'unmodified_drivers')
-rw-r--r-- | unmodified_drivers/linux-2.6/platform-pci/machine_reboot.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/unmodified_drivers/linux-2.6/platform-pci/machine_reboot.c b/unmodified_drivers/linux-2.6/platform-pci/machine_reboot.c index 15ceef8da6..bd58d2ceb5 100644 --- a/unmodified_drivers/linux-2.6/platform-pci/machine_reboot.c +++ b/unmodified_drivers/linux-2.6/platform-pci/machine_reboot.c @@ -12,6 +12,12 @@ struct ap_suspend_info { }; /* + * Use a rwlock to protect the hypercall page from being executed in AP context + * while the BSP is re-initializing it after restore. + */ +static DEFINE_RWLOCK(suspend_lock); + +/* * Spinning prevents, for example, APs touching grant table entries while * the shared grant table is not mapped into the address space imemdiately * after resume. @@ -27,7 +33,9 @@ static void ap_suspend(void *_info) while (info->do_spin) { cpu_relax(); + read_lock(&suspend_lock); HYPERVISOR_yield(); + read_unlock(&suspend_lock); } mb(); @@ -43,7 +51,9 @@ static int bp_suspend(void) suspend_cancelled = HYPERVISOR_shutdown(SHUTDOWN_suspend); if (!suspend_cancelled) { + write_lock(&suspend_lock); platform_pci_resume(); + write_unlock(&suspend_lock); gnttab_resume(); irq_resume(); } |