[GIT PULL] s390 updates for 5.19-rc4

[Alexander Gordeev]

Hello Linus,

please pull s390 changes for 5.19-rc4.

Thank you,
Alexander

The following changes since commit a111daf0c53ae91e71fd2bfe7497862d14132e3e:

  Linux 5.19-rc3 (2022-06-19 15:06:47 -0500)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git tags/s390-5.19-4

for you to fetch changes up to 21e876448792af2dd5261338907c72bdf37fa056

  s390/pai: Fix multiple concurrent event installation (2022-06-15 14:02:07 +0200)

----------------------------------------------------------------
s390 updates for 5.19-rc4

- Fix perf stat accounting for cryptography counters when multiple
  events are installed concurrently.

- Prevent installation of unsupported perf events for cryptography
  counters.

- Treat perf events cpum_cf/CPU_CYCLES/ and cpu_cf/INSTRUCTIONS/
  identical to basic events CPU_CYCLES" and INSTRUCTIONS, since
  they address the same hardware.

- Restore kcrash operation which was broken by commit 5d8de293c224
  ("vmcore: convert copy_oldmem_page() to take an iov_iter").

----------------------------------------------------------------
Alexander Gordeev (2):
  s390/crash: add missing iterator advance in copy_oldmem_page()
  s390/crash: make copy_oldmem_page() return number of bytes copied

Thomas Richter (3):
  s390/cpumf: Handle events cycles and instructions identical
  s390/pai: Prevent invalid event number for pai_crypto PMU
  s390/pai: Fix multiple concurrent event installation

 arch/s390/kernel/crash_dump.c      | 10 +++++++++-
 arch/s390/kernel/perf_cpum_cf.c    | 22 +++++++++++++++++++++-
 arch/s390/kernel/perf_pai_crypto.c | 20 +++++++++++++++-----
 3 files changed, 45 insertions(+), 7 deletions(-)

diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c
index a2c1c55daec0..28124d0fa1d5 100644
--- a/arch/s390/kernel/crash_dump.c
+++ b/arch/s390/kernel/crash_dump.c
@@ -219,6 +219,11 @@ ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize,
 	unsigned long src;
 	int rc;
 
+	if (!(iter_is_iovec(iter) || iov_iter_is_kvec(iter)))
+		return -EINVAL;
+	/* Multi-segment iterators are not supported */
+	if (iter->nr_segs > 1)
+		return -EINVAL;
 	if (!csize)
 		return 0;
 	src = pfn_to_phys(pfn) + offset;
@@ -228,7 +233,10 @@ ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize,
 		rc = copy_oldmem_user(iter->iov->iov_base, src, csize);
 	else
 		rc = copy_oldmem_kernel(iter->kvec->iov_base, src, csize);
-	return rc;
+	if (rc < 0)
+		return rc;
+	iov_iter_advance(iter, csize);
+	return csize;
 }
 
 /*
diff --git a/arch/s390/kernel/perf_cpum_cf.c b/arch/s390/kernel/perf_cpum_cf.c
index 483ab5e10164..f7dd3c849e68 100644
--- a/arch/s390/kernel/perf_cpum_cf.c
+++ b/arch/s390/kernel/perf_cpum_cf.c
@@ -516,6 +516,26 @@ static int __hw_perf_event_init(struct perf_event *event, unsigned int type)
 	return err;
 }
 
+/* Events CPU_CYLCES and INSTRUCTIONS can be submitted with two different
+ * attribute::type values:
+ * - PERF_TYPE_HARDWARE:
+ * - pmu->type:
+ * Handle both type of invocations identical. They address the same hardware.
+ * The result is different when event modifiers exclude_kernel and/or
+ * exclude_user are also set.
+ */
+static int cpumf_pmu_event_type(struct perf_event *event)
+{
+	u64 ev = event->attr.config;
+
+	if (cpumf_generic_events_basic[PERF_COUNT_HW_CPU_CYCLES] == ev ||
+	    cpumf_generic_events_basic[PERF_COUNT_HW_INSTRUCTIONS] == ev ||
+	    cpumf_generic_events_user[PERF_COUNT_HW_CPU_CYCLES] == ev ||
+	    cpumf_generic_events_user[PERF_COUNT_HW_INSTRUCTIONS] == ev)
+		return PERF_TYPE_HARDWARE;
+	return PERF_TYPE_RAW;
+}
+
 static int cpumf_pmu_event_init(struct perf_event *event)
 {
 	unsigned int type = event->attr.type;
@@ -525,7 +545,7 @@ static int cpumf_pmu_event_init(struct perf_event *event)
 		err = __hw_perf_event_init(event, type);
 	else if (event->pmu->type == type)
 		/* Registered as unknown PMU */
-		err = __hw_perf_event_init(event, PERF_TYPE_RAW);
+		err = __hw_perf_event_init(event, cpumf_pmu_event_type(event));
 	else
 		return -ENOENT;
 
diff --git a/arch/s390/kernel/perf_pai_crypto.c b/arch/s390/kernel/perf_pai_crypto.c
index 8c1545946d85..b38b4ae01589 100644
--- a/arch/s390/kernel/perf_pai_crypto.c
+++ b/arch/s390/kernel/perf_pai_crypto.c
@@ -193,8 +193,9 @@ static int paicrypt_event_init(struct perf_event *event)
 	/* PAI crypto PMU registered as PERF_TYPE_RAW, check event type */
 	if (a->type != PERF_TYPE_RAW && event->pmu->type != a->type)
 		return -ENOENT;
-	/* PAI crypto event must be valid */
-	if (a->config > PAI_CRYPTO_BASE + paicrypt_cnt)
+	/* PAI crypto event must be in valid range */
+	if (a->config < PAI_CRYPTO_BASE ||
+	    a->config > PAI_CRYPTO_BASE + paicrypt_cnt)
 		return -EINVAL;
 	/* Allow only CPU wide operation, no process context for now. */
 	if (event->hw.target || event->cpu == -1)
@@ -208,6 +209,12 @@ static int paicrypt_event_init(struct perf_event *event)
 	if (rc)
 		return rc;
 
+	/* Event initialization sets last_tag to 0. When later on the events
+	 * are deleted and re-added, do not reset the event count value to zero.
+	 * Events are added, deleted and re-added when 2 or more events
+	 * are active at the same time.
+	 */
+	event->hw.last_tag = 0;
 	cpump->event = event;
 	event->destroy = paicrypt_event_destroy;
 
@@ -242,9 +249,12 @@ static void paicrypt_start(struct perf_event *event, int flags)
 {
 	u64 sum;
 
-	sum = paicrypt_getall(event);		/* Get current value */
-	local64_set(&event->hw.prev_count, sum);
-	local64_set(&event->count, 0);
+	if (!event->hw.last_tag) {
+		event->hw.last_tag = 1;
+		sum = paicrypt_getall(event);		/* Get current value */
+		local64_set(&event->count, 0);
+		local64_set(&event->hw.prev_count, sum);
+	}
 }
 
 static int paicrypt_add(struct perf_event *event, int flags)