@@ -11,6 +11,7 @@
#include "menu.h"
#include "s390-ccw.h"
+#include "sclp.h"
#define KEYCODE_NO_INP '\0'
#define KEYCODE_ESCAPE '\033'
@@ -117,8 +118,12 @@ static int get_index(void)
memset(buf, 0, sizeof(buf));
+ sclp_set_write_mask(SCLP_EVENT_MASK_MSG_ASCII, SCLP_EVENT_MASK_MSG_ASCII);
len = read_prompt(buf, sizeof(buf));
+ sclp_set_write_mask(0, SCLP_EVENT_MASK_MSG_ASCII);
+ sclp_print(""); /* Clear any pending service int */
+
/* If no input, boot default */
if (len == 0) {
return 0;
@@ -69,6 +69,7 @@ unsigned int get_loadparm_index(void);
/* sclp.c */
void sclp_print(const char *string);
+void sclp_set_write_mask(uint32_t receive_mask, uint32_t send_mask);
void sclp_setup(void);
void sclp_get_loadparm_ascii(char *loadparm);
int sclp_read(char *str, size_t count);
@@ -46,23 +46,21 @@ static int sclp_service_call(unsigned int command, void *sccb)
return 0;
}
-static void sclp_set_write_mask(void)
+void sclp_set_write_mask(uint32_t receive_mask, uint32_t send_mask)
{
WriteEventMask *sccb = (void *)_sccb;
sccb->h.length = sizeof(WriteEventMask);
sccb->mask_length = sizeof(unsigned int);
- sccb->receive_mask = SCLP_EVENT_MASK_MSG_ASCII;
- sccb->cp_receive_mask = SCLP_EVENT_MASK_MSG_ASCII;
- sccb->send_mask = SCLP_EVENT_MASK_MSG_ASCII;
- sccb->cp_send_mask = SCLP_EVENT_MASK_MSG_ASCII;
+ sccb->cp_receive_mask = receive_mask;
+ sccb->cp_send_mask = send_mask;
sclp_service_call(SCLP_CMD_WRITE_EVENT_MASK, sccb);
}
void sclp_setup(void)
{
- sclp_set_write_mask();
+ sclp_set_write_mask(0, SCLP_EVENT_MASK_MSG_ASCII);
}
static int _strlen(const char *str)
It is possible while waiting for multiple types of external interrupts that we might have pending irqs remaining between irq consumption and irq-type disabling. Those interrupts could potentially propagate to the guest after IPL completes and cause unwanted behavior. As it is today, the SCLP will only recognize write events that are enabled by the control program's send and receive masks. To limit the window for, and prevent further irqs from, ASCII console events (specifically keystrokes), we should only enable the control program's receive mask when we need it. As an additional measure, once we've disabled/cleared the control program's receive mask, we will print an empty string in order to consume any pending service interrupt. Signed-off-by: Collin L. Walling <walling@linux.vnet.ibm.com> --- pc-bios/s390-ccw/menu.c | 5 +++++ pc-bios/s390-ccw/s390-ccw.h | 1 + pc-bios/s390-ccw/sclp.c | 10 ++++------ 3 files changed, 10 insertions(+), 6 deletions(-)