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authorVasily Gorbik <gor@linux.ibm.com>2019-11-22 19:18:58 +0100
committerVasily Gorbik <gor@linux.ibm.com>2019-11-30 10:52:48 +0100
commite7409367abe54ad04868552b9d9fe4a56acc753d (patch)
tree4de5d1e67c4926c97eec152aaea8c25db3eb1f34 /arch/s390/lib
parent0610154650f161d56a0bef0d9678ae1de7360019 (diff)
s390/test_unwind: add irq context tests
Add unwinding from irq context tests. Unwinder should be able to unwind through irq stack to task stack up to task pt_regs. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'arch/s390/lib')
-rw-r--r--arch/s390/lib/test_unwind.c45
1 files changed, 45 insertions, 0 deletions
diff --git a/arch/s390/lib/test_unwind.c b/arch/s390/lib/test_unwind.c
index db94e657c056..72fa745281f0 100644
--- a/arch/s390/lib/test_unwind.c
+++ b/arch/s390/lib/test_unwind.c
@@ -11,6 +11,8 @@
#include <linux/module.h>
#include <linux/string.h>
#include <linux/wait.h>
+#include <asm/irq.h>
+#include <asm/delay.h>
#define BT_BUF_SIZE (PAGE_SIZE * 4)
@@ -100,11 +102,15 @@ static noinline int test_unwind(struct task_struct *task, struct pt_regs *regs,
/* State of the task being unwound. */
struct unwindme {
int flags;
+ int ret;
+ struct task_struct *task;
struct completion task_ready;
wait_queue_head_t task_wq;
unsigned long sp;
};
+static struct unwindme *unwindme;
+
/* Values of unwindme.flags. */
#define UWM_DEFAULT 0x0
#define UWM_THREAD 0x1 /* Unwind a separate task. */
@@ -112,6 +118,7 @@ struct unwindme {
#define UWM_SP 0x4 /* Pass sp to test_unwind(). */
#define UWM_CALLER 0x8 /* Unwind starting from caller. */
#define UWM_SWITCH_STACK 0x10 /* Use CALL_ON_STACK. */
+#define UWM_IRQ 0x20 /* Unwind from irq context. */
static __always_inline unsigned long get_psw_addr(void)
{
@@ -173,6 +180,34 @@ static noinline int unwindme_func1(void *u)
return unwindme_func2((struct unwindme *)u);
}
+static void unwindme_irq_handler(struct ext_code ext_code,
+ unsigned int param32,
+ unsigned long param64)
+{
+ struct unwindme *u = READ_ONCE(unwindme);
+
+ if (u && u->task == current) {
+ unwindme = NULL;
+ u->task = NULL;
+ u->ret = unwindme_func1(u);
+ }
+}
+
+static int test_unwind_irq(struct unwindme *u)
+{
+ preempt_disable();
+ if (register_external_irq(EXT_IRQ_CLK_COMP, unwindme_irq_handler)) {
+ pr_info("Couldn't reqister external interrupt handler");
+ return -1;
+ }
+ u->task = current;
+ unwindme = u;
+ udelay(1);
+ unregister_external_irq(EXT_IRQ_CLK_COMP, unwindme_irq_handler);
+ preempt_enable();
+ return u->ret;
+}
+
/* Spawns a task and passes it to test_unwind(). */
static int test_unwind_task(struct unwindme *u)
{
@@ -211,6 +246,8 @@ static int test_unwind_flags(int flags)
u.flags = flags;
if (u.flags & UWM_THREAD)
return test_unwind_task(&u);
+ else if (u.flags & UWM_IRQ)
+ return test_unwind_irq(&u);
else
return unwindme_func1(&u);
}
@@ -241,6 +278,14 @@ do { \
TEST(UWM_THREAD);
TEST(UWM_THREAD | UWM_SP);
TEST(UWM_THREAD | UWM_CALLER | UWM_SP);
+ TEST(UWM_IRQ);
+ TEST(UWM_IRQ | UWM_SWITCH_STACK);
+ TEST(UWM_IRQ | UWM_SP);
+ TEST(UWM_IRQ | UWM_REGS);
+ TEST(UWM_IRQ | UWM_SP | UWM_REGS);
+ TEST(UWM_IRQ | UWM_CALLER | UWM_SP);
+ TEST(UWM_IRQ | UWM_CALLER | UWM_SP | UWM_REGS);
+ TEST(UWM_IRQ | UWM_CALLER | UWM_SP | UWM_REGS | UWM_SWITCH_STACK);
#undef TEST
return ret;