[GIT PULL] s390 fixes for 5.13-rc8

From: Vasily Gorbik
Date: Sat Jun 26 2021 - 08:20:03 EST


Hello Linus,

please pull s390 fixes for 5.13-rc8.

Thank you,
Vasily

The following changes since commit 13311e74253fe64329390df80bed3f07314ddd61:

Linux 5.13-rc7 (2021-06-20 15:03:15 -0700)

are available in the Git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git tags/s390-5.13-5

for you to fetch changes up to 67147e96a332b56c7206238162771d82467f86c0:

s390/stack: fix possible register corruption with stack switch helper (2021-06-21 11:19:18 +0200)

----------------------------------------------------------------
- Fix couple of late pt_regs flags handling findings of conversion to
generic entry.

- Fix potential register clobbering in stack switch helper.

- Fix thread/group masks for offline cpus.

- Fix cleanup of mdev resources when remove callback is invoked in vfio-ap
code.

----------------------------------------------------------------
Heiko Carstens (1):
s390/stack: fix possible register corruption with stack switch helper

Sven Schnelle (3):
s390: fix system call restart with multiple signals
s390: clear pt_regs::flags on irq entry
s390/topology: clear thread/group maps for offline cpus

Tony Krowiak (1):
s390/vfio-ap: clean up mdev resources when remove callback invoked

arch/s390/include/asm/stacktrace.h | 18 +++++++++++-------
arch/s390/kernel/entry.S | 1 +
arch/s390/kernel/signal.c | 1 -
arch/s390/kernel/topology.c | 12 +++++++++---
drivers/s390/crypto/vfio_ap_ops.c | 10 ----------
5 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/arch/s390/include/asm/stacktrace.h b/arch/s390/include/asm/stacktrace.h
index 2b543163d90a..76c6034428be 100644
--- a/arch/s390/include/asm/stacktrace.h
+++ b/arch/s390/include/asm/stacktrace.h
@@ -91,12 +91,16 @@ struct stack_frame {
CALL_ARGS_4(arg1, arg2, arg3, arg4); \
register unsigned long r4 asm("6") = (unsigned long)(arg5)

-#define CALL_FMT_0 "=&d" (r2) :
-#define CALL_FMT_1 "+&d" (r2) :
-#define CALL_FMT_2 CALL_FMT_1 "d" (r3),
-#define CALL_FMT_3 CALL_FMT_2 "d" (r4),
-#define CALL_FMT_4 CALL_FMT_3 "d" (r5),
-#define CALL_FMT_5 CALL_FMT_4 "d" (r6),
+/*
+ * To keep this simple mark register 2-6 as being changed (volatile)
+ * by the called function, even though register 6 is saved/nonvolatile.
+ */
+#define CALL_FMT_0 "=&d" (r2)
+#define CALL_FMT_1 "+&d" (r2)
+#define CALL_FMT_2 CALL_FMT_1, "+&d" (r3)
+#define CALL_FMT_3 CALL_FMT_2, "+&d" (r4)
+#define CALL_FMT_4 CALL_FMT_3, "+&d" (r5)
+#define CALL_FMT_5 CALL_FMT_4, "+&d" (r6)

#define CALL_CLOBBER_5 "0", "1", "14", "cc", "memory"
#define CALL_CLOBBER_4 CALL_CLOBBER_5
@@ -118,7 +122,7 @@ struct stack_frame {
" brasl 14,%[_fn]\n" \
" la 15,0(%[_prev])\n" \
: [_prev] "=&a" (prev), CALL_FMT_##nr \
- [_stack] "R" (stack), \
+ : [_stack] "R" (stack), \
[_bc] "i" (offsetof(struct stack_frame, back_chain)), \
[_frame] "d" (frame), \
[_fn] "X" (fn) : CALL_CLOBBER_##nr); \
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 9cc71ca9a88f..e84f495e7eb2 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -418,6 +418,7 @@ ENTRY(\name)
xgr %r6,%r6
xgr %r7,%r7
xgr %r10,%r10
+ xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
stmg %r8,%r9,__PT_PSW(%r11)
tm %r8,0x0001 # coming from user space?
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index 90163e6184f5..080e7aed181f 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -512,7 +512,6 @@ void arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal)

/* No handlers present - check for system call restart */
clear_pt_regs_flag(regs, PIF_SYSCALL);
- clear_pt_regs_flag(regs, PIF_SYSCALL_RESTART);
if (current->thread.system_call) {
regs->int_code = current->thread.system_call;
switch (regs->gprs[2]) {
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c
index bfcc327acc6b..26aa2614ee35 100644
--- a/arch/s390/kernel/topology.c
+++ b/arch/s390/kernel/topology.c
@@ -66,7 +66,10 @@ static void cpu_group_map(cpumask_t *dst, struct mask_info *info, unsigned int c
{
static cpumask_t mask;

- cpumask_copy(&mask, cpumask_of(cpu));
+ cpumask_clear(&mask);
+ if (!cpu_online(cpu))
+ goto out;
+ cpumask_set_cpu(cpu, &mask);
switch (topology_mode) {
case TOPOLOGY_MODE_HW:
while (info) {
@@ -83,10 +86,10 @@ static void cpu_group_map(cpumask_t *dst, struct mask_info *info, unsigned int c
default:
fallthrough;
case TOPOLOGY_MODE_SINGLE:
- cpumask_copy(&mask, cpumask_of(cpu));
break;
}
cpumask_and(&mask, &mask, cpu_online_mask);
+out:
cpumask_copy(dst, &mask);
}

@@ -95,7 +98,10 @@ static void cpu_thread_map(cpumask_t *dst, unsigned int cpu)
static cpumask_t mask;
int i;

- cpumask_copy(&mask, cpumask_of(cpu));
+ cpumask_clear(&mask);
+ if (!cpu_online(cpu))
+ goto out;
+ cpumask_set_cpu(cpu, &mask);
if (topology_mode != TOPOLOGY_MODE_HW)
goto out;
cpu -= cpu % (smp_cpu_mtid + 1);
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index b2c7e10dfdcd..122c85c22469 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -366,16 +366,6 @@ static int vfio_ap_mdev_remove(struct mdev_device *mdev)
struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);

mutex_lock(&matrix_dev->lock);
-
- /*
- * If the KVM pointer is in flux or the guest is running, disallow
- * un-assignment of control domain.
- */
- if (matrix_mdev->kvm_busy || matrix_mdev->kvm) {
- mutex_unlock(&matrix_dev->lock);
- return -EBUSY;
- }
-
vfio_ap_mdev_reset_queues(mdev);
list_del(&matrix_mdev->node);
kfree(matrix_mdev);