[PATCH 5.18 762/879] s390/stp: clock_delta should be signed

Greg Kroah-Hartman
2022-06-08T01:03:56Z

From: Sven Schnelle <svens@linux.ibm.com>

commit 5ace65ebb5ce9fe1cc8fdbdd97079fb566ef0ea4 upstream.

clock_delta is declared as unsigned long in various places. However,
the clock sync delta can be negative. This would add a huge positive
offset in clock_sync_global where clock_delta is added to clk.eitod
which is a 72 bit integer. Declare it as signed long to fix this.

Cc: stable@vger.kernel.org
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/s390/include/asm/cio.h | 2 +-
arch/s390/kernel/time.c | 8 ++++----
drivers/s390/cio/chsc.c | 4 ++--
3 files changed, 7 insertions(+), 7 deletions(-)

--- a/arch/s390/include/asm/cio.h
+++ b/arch/s390/include/asm/cio.h
@@ -369,7 +369,7 @@ void cio_gp_dma_destroy(struct gen_pool
struct gen_pool *cio_gp_dma_create(struct device *dma_dev, int nr_pages);

/* Function from drivers/s390/cio/chsc.c */
-int chsc_sstpc(void *page, unsigned int op, u16 ctrl, u64 *clock_delta);
+int chsc_sstpc(void *page, unsigned int op, u16 ctrl, long *clock_delta);
int chsc_sstpi(void *page, void *result, size_t size);
int chsc_stzi(void *page, void *result, size_t size);
int chsc_sgib(u32 origin);
--- a/arch/s390/kernel/time.c
+++ b/arch/s390/kernel/time.c
@@ -364,7 +364,7 @@ static inline int check_sync_clock(void)
* Apply clock delta to the global data structures.
* This is called once on the CPU that performed the clock sync.
*/
-static void clock_sync_global(unsigned long delta)
+static void clock_sync_global(long delta)
{
unsigned long now, adj;
struct ptff_qto qto;
@@ -400,7 +400,7 @@ static void clock_sync_global(unsigned l
* Apply clock delta to the per-CPU data structures of this CPU.
* This is called for each online CPU after the call to clock_sync_global.
*/
-static void clock_sync_local(unsigned long delta)
+static void clock_sync_local(long delta)
{
/* Add the delta to the clock comparator. */
if (S390_lowcore.clock_comparator != clock_comparator_max) {
@@ -424,7 +424,7 @@ static void __init time_init_wq(void)
struct clock_sync_data {
atomic_t cpus;
int in_sync;
- unsigned long clock_delta;
+ long clock_delta;
};

/*
@@ -544,7 +544,7 @@ static int stpinfo_valid(void)
static int stp_sync_clock(void *data)
{
struct clock_sync_data *sync = data;
- u64 clock_delta, flags;
+ long clock_delta, flags;
static int first;
int rc;

--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -1255,7 +1255,7 @@ exit:
EXPORT_SYMBOL_GPL(css_general_characteristics);
EXPORT_SYMBOL_GPL(css_chsc_characteristics);

-int chsc_sstpc(void *page, unsigned int op, u16 ctrl, u64 *clock_delta)
+int chsc_sstpc(void *page, unsigned int op, u16 ctrl, long *clock_delta)
{
struct {
struct chsc_header request;
@@ -1266,7 +1266,7 @@ int chsc_sstpc(void *page, unsigned int
unsigned int rsvd2[5];
struct chsc_header response;
unsigned int rsvd3[3];
- u64 clock_delta;
+ s64 clock_delta;
unsigned int rsvd4[2];
} *rr;
int rc;