[PATCH AUTOSEL 4.19 001/191] s390/qeth: uninstall IRQ handler on device removal

[PATCH AUTOSEL 4.19 001/191] s390/qeth: uninstall IRQ handler on device removal

[Sasha Levin]

From: Julian Wiedmann <jwi@linux.ibm.com>

[ Upstream commit 121ca39aa5585def682a2c8592983442438b84dc ]

When setting up, qeth installs its IRQ handler on the ccw devices. But
the IRQ handler is not cleared on removal - so even after qeth yields
control of the ccw devices, spurious interrupts would still be presented
to us.

Make (de-)installation of the IRQ handler part of the ccw channel
setup/removal helpers, and while at it also add the appropriate locking.
Shift around qeth_setup_channel() to avoid a forward declaration for
qeth_irq().

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/s390/net/qeth_core_main.c | 102 ++++++++++++++++--------------
 1 file changed, 54 insertions(+), 48 deletions(-)

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 461afc276db72..81e2c591acb0b 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -901,44 +901,6 @@ static void qeth_send_control_data_cb(struct qeth_channel *channel,
 	qeth_release_buffer(channel, iob);
 }
 
-static int qeth_setup_channel(struct qeth_channel *channel, bool alloc_buffers)
-{
-	int cnt;
-
-	QETH_DBF_TEXT(SETUP, 2, "setupch");
-
-	channel->ccw = kmalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
-	if (!channel->ccw)
-		return -ENOMEM;
-	channel->state = CH_STATE_DOWN;
-	atomic_set(&channel->irq_pending, 0);
-	init_waitqueue_head(&channel->wait_q);
-
-	if (!alloc_buffers)
-		return 0;
-
-	for (cnt = 0; cnt < QETH_CMD_BUFFER_NO; cnt++) {
-		channel->iob[cnt].data =
-			kzalloc(QETH_BUFSIZE, GFP_DMA|GFP_KERNEL);
-		if (channel->iob[cnt].data == NULL)
-			break;
-		channel->iob[cnt].state = BUF_STATE_FREE;
-		channel->iob[cnt].channel = channel;
-		channel->iob[cnt].callback = qeth_send_control_data_cb;
-		channel->iob[cnt].rc = 0;
-	}
-	if (cnt < QETH_CMD_BUFFER_NO) {
-		kfree(channel->ccw);
-		while (cnt-- > 0)
-			kfree(channel->iob[cnt].data);
-		return -ENOMEM;
-	}
-	channel->io_buf_no = 0;
-	spin_lock_init(&channel->iob_lock);
-
-	return 0;
-}
-
 static int qeth_set_thread_start_bit(struct qeth_card *card,
 		unsigned long thread)
 {
@@ -1339,14 +1301,61 @@ static void qeth_free_buffer_pool(struct qeth_card *card)
 
 static void qeth_clean_channel(struct qeth_channel *channel)
 {
+	struct ccw_device *cdev = channel->ccwdev;
 	int cnt;
 
 	QETH_DBF_TEXT(SETUP, 2, "freech");
+
+	spin_lock_irq(get_ccwdev_lock(cdev));
+	cdev->handler = NULL;
+	spin_unlock_irq(get_ccwdev_lock(cdev));
+
 	for (cnt = 0; cnt < QETH_CMD_BUFFER_NO; cnt++)
 		kfree(channel->iob[cnt].data);
 	kfree(channel->ccw);
 }
 
+static int qeth_setup_channel(struct qeth_channel *channel, bool alloc_buffers)
+{
+	struct ccw_device *cdev = channel->ccwdev;
+	int cnt;
+
+	QETH_DBF_TEXT(SETUP, 2, "setupch");
+
+	channel->ccw = kmalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
+	if (!channel->ccw)
+		return -ENOMEM;
+	channel->state = CH_STATE_DOWN;
+	atomic_set(&channel->irq_pending, 0);
+	init_waitqueue_head(&channel->wait_q);
+
+	spin_lock_irq(get_ccwdev_lock(cdev));
+	cdev->handler = qeth_irq;
+	spin_unlock_irq(get_ccwdev_lock(cdev));
+
+	if (!alloc_buffers)
+		return 0;
+
+	for (cnt = 0; cnt < QETH_CMD_BUFFER_NO; cnt++) {
+		channel->iob[cnt].data =
+			kzalloc(QETH_BUFSIZE, GFP_DMA|GFP_KERNEL);
+		if (channel->iob[cnt].data == NULL)
+			break;
+		channel->iob[cnt].state = BUF_STATE_FREE;
+		channel->iob[cnt].channel = channel;
+		channel->iob[cnt].callback = qeth_send_control_data_cb;
+		channel->iob[cnt].rc = 0;
+	}
+	if (cnt < QETH_CMD_BUFFER_NO) {
+		qeth_clean_channel(channel);
+		return -ENOMEM;
+	}
+	channel->io_buf_no = 0;
+	spin_lock_init(&channel->iob_lock);
+
+	return 0;
+}
+
 static void qeth_set_single_write_queues(struct qeth_card *card)
 {
 	if ((atomic_read(&card->qdio.state) != QETH_QDIO_UNINITIALIZED) &&
@@ -1498,7 +1507,7 @@ static void qeth_core_sl_print(struct seq_file *m, struct service_level *slr)
 			CARD_BUS_ID(card), card->info.mcl_level);
 }
 
-static struct qeth_card *qeth_alloc_card(void)
+static struct qeth_card *qeth_alloc_card(struct ccwgroup_device *gdev)
 {
 	struct qeth_card *card;
 
@@ -1507,6 +1516,11 @@ static struct qeth_card *qeth_alloc_card(void)
 	if (!card)
 		goto out;
 	QETH_DBF_HEX(SETUP, 2, &card, sizeof(void *));
+
+	card->gdev = gdev;
+	CARD_RDEV(card) = gdev->cdev[0];
+	CARD_WDEV(card) = gdev->cdev[1];
+	CARD_DDEV(card) = gdev->cdev[2];
 	if (qeth_setup_channel(&card->read, true))
 		goto out_ip;
 	if (qeth_setup_channel(&card->write, true))
@@ -5745,7 +5759,7 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
 
 	QETH_DBF_TEXT_(SETUP, 2, "%s", dev_name(&gdev->dev));
 
-	card = qeth_alloc_card();
+	card = qeth_alloc_card(gdev);
 	if (!card) {
 		QETH_DBF_TEXT_(SETUP, 2, "1err%d", -ENOMEM);
 		rc = -ENOMEM;
@@ -5761,15 +5775,7 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
 			goto err_card;
 	}
 
-	card->read.ccwdev  = gdev->cdev[0];
-	card->write.ccwdev = gdev->cdev[1];
-	card->data.ccwdev  = gdev->cdev[2];
 	dev_set_drvdata(&gdev->dev, card);
-	card->gdev = gdev;
-	gdev->cdev[0]->handler = qeth_irq;
-	gdev->cdev[1]->handler = qeth_irq;
-	gdev->cdev[2]->handler = qeth_irq;
-
 	qeth_setup_card(card);
 	rc = qeth_update_from_chp_desc(card);
 	if (rc)
-- 
2.20.1

[PATCH AUTOSEL 4.19 002/191] s390/qeth: invoke softirqs after napi_schedule()

[Sasha Levin]

From: Julian Wiedmann <jwi@linux.ibm.com>

[ Upstream commit 4d19db777a2f32c9b76f6fd517ed8960576cb43e ]

Calling napi_schedule() from process context does not ensure that the
NET_RX softirq is run in a timely fashion. So trigger it manually.

This is no big issue with current code. A call to ndo_open() is usually
followed by a ndo_set_rx_mode() call, and for qeth this contains a
spin_unlock_bh(). Except for OSN, where qeth_l2_set_rx_mode() bails out
early.
Nevertheless it's best to not depend on this behaviour, and just fix
the issue at its source like all other drivers do. For instance see
commit 83a0c6e58901 ("i40e: Invoke softirqs after napi_reschedule").

Fixes: a1c3ed4c9ca0 ("qeth: NAPI support for l2 and l3 discipline")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/s390/net/qeth_l2_main.c | 3 +++
 drivers/s390/net/qeth_l3_main.c | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c
index c1c35eccd5b65..95669d47c389e 100644
--- a/drivers/s390/net/qeth_l2_main.c
+++ b/drivers/s390/net/qeth_l2_main.c
@@ -789,7 +789,10 @@ static int __qeth_l2_open(struct net_device *dev)
 
 	if (qdio_stop_irq(card->data.ccwdev, 0) >= 0) {
 		napi_enable(&card->napi);
+		local_bh_disable();
 		napi_schedule(&card->napi);
+		/* kick-start the NAPI softirq: */
+		local_bh_enable();
 	} else
 		rc = -EIO;
 	return rc;
diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index 9c5e801b3f6cb..52e0ae4dc7241 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -2414,7 +2414,10 @@ static int __qeth_l3_open(struct net_device *dev)
 
 	if (qdio_stop_irq(card->data.ccwdev, 0) >= 0) {
 		napi_enable(&card->napi);
+		local_bh_disable();
 		napi_schedule(&card->napi);
+		/* kick-start the NAPI softirq: */
+		local_bh_enable();
 	} else
 		rc = -EIO;
 	return rc;
-- 
2.20.1

[PATCH AUTOSEL 4.19 055/191] s390/zcrypt: enable AP bus scan without a valid default domain

[Sasha Levin]

From: Halil Pasic <pasic@linux.ibm.com>

[ Upstream commit 1c472d46283263497adccd7a0bec64ee2f9c09e5 ]

The AP bus scan is aborted before doing anything worth mentioning if
ap_select_domain() fails, e.g. if the ap_rights.aqm mask is all zeros.
As the result of this the ap bus fails to manage (e.g. create and
register) devices like it is supposed to.

Let us make ap_scan_bus() work even if ap_select_domain() can't select a
default domain. Let's also make ap_select_domain() return void, as there
are no more callers interested in its return value.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reported-by: Michael Mueller <mimu@linux.ibm.com>
Fixes: 7e0bdbe5c21c "s390/zcrypt: AP bus support for alternate driver(s)"
[freude@linux.ibm.com: title and patch header slightly modified]
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/s390/crypto/ap_bus.c | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c
index 3be54651698a3..027a53eec42a5 100644
--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -1223,11 +1223,10 @@ static struct bus_attribute *const ap_bus_attrs[] = {
 };
 
 /**
- * ap_select_domain(): Select an AP domain.
- *
- * Pick one of the 16 AP domains.
+ * ap_select_domain(): Select an AP domain if possible and we haven't
+ * already done so before.
  */
-static int ap_select_domain(void)
+static void ap_select_domain(void)
 {
 	int count, max_count, best_domain;
 	struct ap_queue_status status;
@@ -1242,7 +1241,7 @@ static int ap_select_domain(void)
 	if (ap_domain_index >= 0) {
 		/* Domain has already been selected. */
 		spin_unlock_bh(&ap_domain_lock);
-		return 0;
+		return;
 	}
 	best_domain = -1;
 	max_count = 0;
@@ -1269,11 +1268,8 @@ static int ap_select_domain(void)
 	if (best_domain >= 0) {
 		ap_domain_index = best_domain;
 		AP_DBF(DBF_DEBUG, "new ap_domain_index=%d\n", ap_domain_index);
-		spin_unlock_bh(&ap_domain_lock);
-		return 0;
 	}
 	spin_unlock_bh(&ap_domain_lock);
-	return -ENODEV;
 }
 
 /*
@@ -1351,8 +1347,7 @@ static void ap_scan_bus(struct work_struct *unused)
 	AP_DBF(DBF_DEBUG, "%s running\n", __func__);
 
 	ap_query_configuration(ap_configuration);
-	if (ap_select_domain() != 0)
-		goto out;
+	ap_select_domain();
 
 	for (id = 0; id < AP_DEVICES; id++) {
 		/* check if device is registered */
@@ -1468,12 +1463,11 @@ static void ap_scan_bus(struct work_struct *unused)
 		}
 	} /* end device loop */
 
-	if (defdomdevs < 1)
+	if (ap_domain_index >= 0 && defdomdevs < 1)
 		AP_DBF(DBF_INFO,
 		       "no queue device with default domain %d available\n",
 		       ap_domain_index);
 
-out:
 	mod_timer(&ap_config_timer, jiffies + ap_config_time * HZ);
 }
 
-- 
2.20.1

[PATCH AUTOSEL 4.19 056/191] s390/vdso: avoid 64-bit vdso mapping for compat tasks

[Sasha Levin]

From: Vasily Gorbik <gor@linux.ibm.com>

[ Upstream commit d1befa65823e9c6d013883b8a41d081ec338c489 ]

vdso_fault used is_compat_task function (on s390 it tests "current"
thread_info flags) to distinguish compat tasks and map 31-bit vdso
pages. But "current" task might not correspond to mm context.

When 31-bit compat inferior is executed under gdb, gdb does
PTRACE_PEEKTEXT on vdso page, causing vdso_fault with "current" being
64-bit gdb process. So, 31-bit inferior ends up with 64-bit vdso mapped.

To avoid this problem a new compat_mm flag has been introduced into
mm context. This flag is used in vdso_fault and vdso_mremap instead
of is_compat_task.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/s390/include/asm/mmu.h         | 2 ++
 arch/s390/include/asm/mmu_context.h | 1 +
 arch/s390/kernel/vdso.c             | 8 +++++---
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/s390/include/asm/mmu.h b/arch/s390/include/asm/mmu.h
index a8418e1379eb7..bcfb6371086f2 100644
--- a/arch/s390/include/asm/mmu.h
+++ b/arch/s390/include/asm/mmu.h
@@ -32,6 +32,8 @@ typedef struct {
 	unsigned int uses_cmm:1;
 	/* The gmaps associated with this context are allowed to use huge pages. */
 	unsigned int allow_gmap_hpage_1m:1;
+	/* The mmu context is for compat task */
+	unsigned int compat_mm:1;
 } mm_context_t;
 
 #define INIT_MM_CONTEXT(name)						   \
diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h
index 09b61d0e491f6..e4462202200d7 100644
--- a/arch/s390/include/asm/mmu_context.h
+++ b/arch/s390/include/asm/mmu_context.h
@@ -25,6 +25,7 @@ static inline int init_new_context(struct task_struct *tsk,
 	atomic_set(&mm->context.flush_count, 0);
 	mm->context.gmap_asce = 0;
 	mm->context.flush_mm = 0;
+	mm->context.compat_mm = 0;
 #ifdef CONFIG_PGSTE
 	mm->context.alloc_pgste = page_table_allocate_pgste ||
 		test_thread_flag(TIF_PGSTE) ||
diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c
index 3031cc6dd0ab4..ec31b48a42a52 100644
--- a/arch/s390/kernel/vdso.c
+++ b/arch/s390/kernel/vdso.c
@@ -56,7 +56,7 @@ static vm_fault_t vdso_fault(const struct vm_special_mapping *sm,
 	vdso_pagelist = vdso64_pagelist;
 	vdso_pages = vdso64_pages;
 #ifdef CONFIG_COMPAT
-	if (is_compat_task()) {
+	if (vma->vm_mm->context.compat_mm) {
 		vdso_pagelist = vdso32_pagelist;
 		vdso_pages = vdso32_pages;
 	}
@@ -77,7 +77,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
 
 	vdso_pages = vdso64_pages;
 #ifdef CONFIG_COMPAT
-	if (is_compat_task())
+	if (vma->vm_mm->context.compat_mm)
 		vdso_pages = vdso32_pages;
 #endif
 
@@ -224,8 +224,10 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 
 	vdso_pages = vdso64_pages;
 #ifdef CONFIG_COMPAT
-	if (is_compat_task())
+	if (is_compat_task()) {
 		vdso_pages = vdso32_pages;
+		mm->context.compat_mm = 1;
+	}
 #endif
 	/*
 	 * vDSO has a problem and was disabled, just don't "enable" it for
-- 
2.20.1

[PATCH AUTOSEL 4.19 057/191] s390/vdso: correct CFI annotations of vDSO functions

[Sasha Levin]

From: Vasily Gorbik <gor@linux.ibm.com>

[ Upstream commit 26f4414a45b808f83d42d6fd2fbf4a59ef25e84b ]

Correct stack frame overhead for 31-bit vdso, which should be 96 rather
then 160. This is done by reusing STACK_FRAME_OVERHEAD definition which
contains correct value based on build flags. This fixes stack unwinding
within vdso code for 31-bit processes. While at it replace all hard coded
stack frame overhead values with the same definition in vdso64 as well.

Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/s390/kernel/vdso32/clock_gettime.S | 19 ++++++++++---------
 arch/s390/kernel/vdso32/gettimeofday.S  |  3 ++-
 arch/s390/kernel/vdso64/clock_gettime.S | 25 +++++++++++++------------
 arch/s390/kernel/vdso64/gettimeofday.S  |  3 ++-
 4 files changed, 27 insertions(+), 23 deletions(-)

diff --git a/arch/s390/kernel/vdso32/clock_gettime.S b/arch/s390/kernel/vdso32/clock_gettime.S
index a9418bf975db5..ada5c11a16e5a 100644
--- a/arch/s390/kernel/vdso32/clock_gettime.S
+++ b/arch/s390/kernel/vdso32/clock_gettime.S
@@ -10,6 +10,7 @@
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
 #include <asm/dwarf.h>
+#include <asm/ptrace.h>
 
 	.text
 	.align 4
@@ -18,8 +19,8 @@
 __kernel_clock_gettime:
 	CFI_STARTPROC
 	ahi	%r15,-16
-	CFI_DEF_CFA_OFFSET 176
-	CFI_VAL_OFFSET 15, -160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD+16
+	CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
 	basr	%r5,0
 0:	al	%r5,21f-0b(%r5)			/* get &_vdso_data */
 	chi	%r2,__CLOCK_REALTIME_COARSE
@@ -72,13 +73,13 @@ __kernel_clock_gettime:
 	st	%r1,4(%r3)			/* store tp->tv_nsec */
 	lhi	%r2,0
 	ahi	%r15,16
-	CFI_DEF_CFA_OFFSET 160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD
 	CFI_RESTORE 15
 	br	%r14
 
 	/* CLOCK_MONOTONIC_COARSE */
-	CFI_DEF_CFA_OFFSET 176
-	CFI_VAL_OFFSET 15, -160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD+16
+	CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
 9:	l	%r4,__VDSO_UPD_COUNT+4(%r5)	/* load update counter */
 	tml	%r4,0x0001			/* pending update ? loop */
 	jnz	9b
@@ -158,17 +159,17 @@ __kernel_clock_gettime:
 	st	%r1,4(%r3)			/* store tp->tv_nsec */
 	lhi	%r2,0
 	ahi	%r15,16
-	CFI_DEF_CFA_OFFSET 160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD
 	CFI_RESTORE 15
 	br	%r14
 
 	/* Fallback to system call */
-	CFI_DEF_CFA_OFFSET 176
-	CFI_VAL_OFFSET 15, -160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD+16
+	CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
 19:	lhi	%r1,__NR_clock_gettime
 	svc	0
 	ahi	%r15,16
-	CFI_DEF_CFA_OFFSET 160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD
 	CFI_RESTORE 15
 	br	%r14
 	CFI_ENDPROC
diff --git a/arch/s390/kernel/vdso32/gettimeofday.S b/arch/s390/kernel/vdso32/gettimeofday.S
index 3c0db0fa6ad90..b23063fbc892c 100644
--- a/arch/s390/kernel/vdso32/gettimeofday.S
+++ b/arch/s390/kernel/vdso32/gettimeofday.S
@@ -10,6 +10,7 @@
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
 #include <asm/dwarf.h>
+#include <asm/ptrace.h>
 
 	.text
 	.align 4
@@ -19,7 +20,7 @@ __kernel_gettimeofday:
 	CFI_STARTPROC
 	ahi	%r15,-16
 	CFI_ADJUST_CFA_OFFSET 16
-	CFI_VAL_OFFSET 15, -160
+	CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
 	basr	%r5,0
 0:	al	%r5,13f-0b(%r5)			/* get &_vdso_data */
 1:	ltr	%r3,%r3				/* check if tz is NULL */
diff --git a/arch/s390/kernel/vdso64/clock_gettime.S b/arch/s390/kernel/vdso64/clock_gettime.S
index fac3ab5ec83a9..9d2ee79b90f25 100644
--- a/arch/s390/kernel/vdso64/clock_gettime.S
+++ b/arch/s390/kernel/vdso64/clock_gettime.S
@@ -10,6 +10,7 @@
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
 #include <asm/dwarf.h>
+#include <asm/ptrace.h>
 
 	.text
 	.align 4
@@ -18,8 +19,8 @@
 __kernel_clock_gettime:
 	CFI_STARTPROC
 	aghi	%r15,-16
-	CFI_DEF_CFA_OFFSET 176
-	CFI_VAL_OFFSET 15, -160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD+16
+	CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
 	larl	%r5,_vdso_data
 	cghi	%r2,__CLOCK_REALTIME_COARSE
 	je	4f
@@ -56,13 +57,13 @@ __kernel_clock_gettime:
 	stg	%r1,8(%r3)			/* store tp->tv_nsec */
 	lghi	%r2,0
 	aghi	%r15,16
-	CFI_DEF_CFA_OFFSET 160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD
 	CFI_RESTORE 15
 	br	%r14
 
 	/* CLOCK_MONOTONIC_COARSE */
-	CFI_DEF_CFA_OFFSET 176
-	CFI_VAL_OFFSET 15, -160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD+16
+	CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
 3:	lg	%r4,__VDSO_UPD_COUNT(%r5)	/* load update counter */
 	tmll	%r4,0x0001			/* pending update ? loop */
 	jnz	3b
@@ -115,13 +116,13 @@ __kernel_clock_gettime:
 	stg	%r1,8(%r3)			/* store tp->tv_nsec */
 	lghi	%r2,0
 	aghi	%r15,16
-	CFI_DEF_CFA_OFFSET 160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD
 	CFI_RESTORE 15
 	br	%r14
 
 	/* CPUCLOCK_VIRT for this thread */
-	CFI_DEF_CFA_OFFSET 176
-	CFI_VAL_OFFSET 15, -160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD+16
+	CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
 9:	lghi	%r4,0
 	icm	%r0,15,__VDSO_ECTG_OK(%r5)
 	jz	12f
@@ -142,17 +143,17 @@ __kernel_clock_gettime:
 	stg	%r4,8(%r3)
 	lghi	%r2,0
 	aghi	%r15,16
-	CFI_DEF_CFA_OFFSET 160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD
 	CFI_RESTORE 15
 	br	%r14
 
 	/* Fallback to system call */
-	CFI_DEF_CFA_OFFSET 176
-	CFI_VAL_OFFSET 15, -160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD+16
+	CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
 12:	lghi	%r1,__NR_clock_gettime
 	svc	0
 	aghi	%r15,16
-	CFI_DEF_CFA_OFFSET 160
+	CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD
 	CFI_RESTORE 15
 	br	%r14
 	CFI_ENDPROC
diff --git a/arch/s390/kernel/vdso64/gettimeofday.S b/arch/s390/kernel/vdso64/gettimeofday.S
index 6e1f0b421695a..aebe10dc7c99a 100644
--- a/arch/s390/kernel/vdso64/gettimeofday.S
+++ b/arch/s390/kernel/vdso64/gettimeofday.S
@@ -10,6 +10,7 @@
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
 #include <asm/dwarf.h>
+#include <asm/ptrace.h>
 
 	.text
 	.align 4
@@ -19,7 +20,7 @@ __kernel_gettimeofday:
 	CFI_STARTPROC
 	aghi	%r15,-16
 	CFI_ADJUST_CFA_OFFSET 16
-	CFI_VAL_OFFSET 15, -160
+	CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
 	larl	%r5,_vdso_data
 0:	ltgr	%r3,%r3				/* check if tz is NULL */
 	je	1f
-- 
2.20.1

[PATCH AUTOSEL 4.19 189/191] s390/vdso: correct vdso mapping for compat tasks

[Sasha Levin]

From: Vasily Gorbik <gor@linux.ibm.com>

[ Upstream commit 190f056fba230abee80712eb810939ef9a8c462f ]

While "s390/vdso: avoid 64-bit vdso mapping for compat tasks" fixed
64-bit vdso mapping for compat tasks under gdb it introduced another
problem. "compat_mm" flag is not inherited during fork and when
31-bit process forks a child (but does not perform exec) it ends up
with 64-bit vdso. To address that, init_new_context (which is called
during fork and exec) now initialize compat_mm based on thread TIF_31BIT
flag. Later compat_mm is adjusted in arch_setup_additional_pages, which
is called during exec.

Fixes: d1befa65823e ("s390/vdso: avoid 64-bit vdso mapping for compat tasks")
Reported-by: Stefan Liebler <stli@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@vger.kernel.org> # v4.20+
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/s390/include/asm/mmu_context.h | 2 +-
 arch/s390/kernel/vdso.c             | 5 ++---
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h
index e4462202200d7..8d04e6f3f7964 100644
--- a/arch/s390/include/asm/mmu_context.h
+++ b/arch/s390/include/asm/mmu_context.h
@@ -25,7 +25,7 @@ static inline int init_new_context(struct task_struct *tsk,
 	atomic_set(&mm->context.flush_count, 0);
 	mm->context.gmap_asce = 0;
 	mm->context.flush_mm = 0;
-	mm->context.compat_mm = 0;
+	mm->context.compat_mm = test_thread_flag(TIF_31BIT);
 #ifdef CONFIG_PGSTE
 	mm->context.alloc_pgste = page_table_allocate_pgste ||
 		test_thread_flag(TIF_PGSTE) ||
diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c
index ec31b48a42a52..7ab7d256d1eb7 100644
--- a/arch/s390/kernel/vdso.c
+++ b/arch/s390/kernel/vdso.c
@@ -224,10 +224,9 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 
 	vdso_pages = vdso64_pages;
 #ifdef CONFIG_COMPAT
-	if (is_compat_task()) {
+	mm->context.compat_mm = is_compat_task();
+	if (mm->context.compat_mm)
 		vdso_pages = vdso32_pages;
-		mm->context.compat_mm = 1;
-	}
 #endif
 	/*
 	 * vDSO has a problem and was disabled, just don't "enable" it for
-- 
2.20.1