diff options
Diffstat (limited to 'drivers/misc')
| -rw-r--r-- | drivers/misc/lkdtm/bugs.c | 30 |
1 files changed, 29 insertions, 1 deletions
diff --git a/drivers/misc/lkdtm/bugs.c b/drivers/misc/lkdtm/bugs.c index c66cc05a68c4..b080eb2335eb 100644 --- a/drivers/misc/lkdtm/bugs.c +++ b/drivers/misc/lkdtm/bugs.c @@ -6,12 +6,14 @@ * test source files. */ #include "lkdtm.h" +#include <linux/cpu.h> #include <linux/list.h> #include <linux/sched.h> #include <linux/sched/signal.h> #include <linux/sched/task_stack.h> -#include <linux/uaccess.h> #include <linux/slab.h> +#include <linux/stop_machine.h> +#include <linux/uaccess.h> #if IS_ENABLED(CONFIG_X86_32) && !IS_ENABLED(CONFIG_UML) #include <asm/desc.h> @@ -73,6 +75,31 @@ static void lkdtm_PANIC(void) panic("dumptest"); } +static int panic_stop_irqoff_fn(void *arg) +{ + atomic_t *v = arg; + + /* + * As stop_machine() disables interrupts, all CPUs within this function + * have interrupts disabled and cannot take a regular IPI. + * + * The last CPU which enters here will trigger a panic, and as all CPUs + * cannot take a regular IPI, we'll only be able to stop secondaries if + * smp_send_stop() or crash_smp_send_stop() uses an NMI. + */ + if (atomic_inc_return(v) == num_online_cpus()) + panic("panic stop irqoff test"); + + for (;;) + cpu_relax(); +} + +static void lkdtm_PANIC_STOP_IRQOFF(void) +{ + atomic_t v = ATOMIC_INIT(0); + stop_machine(panic_stop_irqoff_fn, &v, cpu_online_mask); +} + static void lkdtm_BUG(void) { BUG(); @@ -638,6 +665,7 @@ static noinline void lkdtm_CORRUPT_PAC(void) static struct crashtype crashtypes[] = { CRASHTYPE(PANIC), + CRASHTYPE(PANIC_STOP_IRQOFF), CRASHTYPE(BUG), CRASHTYPE(WARNING), CRASHTYPE(WARNING_MESSAGE), |