Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Martin Schwidefsky:

 - Improvements for the spectre defense:
    * The spectre related code is consolidated to a single file
      nospec-branch.c
    * Automatic enable/disable for the spectre v2 defenses (expoline vs.
      nobp)
    * Syslog messages for specve v2 are added
    * Enable CONFIG_GENERIC_CPU_VULNERABILITIES and define the attribute
      functions for spectre v1 and v2

 - Add helper macros for assembler alternatives and use them to shorten
   the code in entry.S.

 - Add support for persistent configuration data via the SCLP Store Data
   interface. The H/W interface requires a page table that uses 4K pages
   only, the code to setup such an address space is added as well.

 - Enable virtio GPU emulation in QEMU. To do this the depends
   statements for a few common Kconfig options are modified.

 - Add support for format-3 channel path descriptors and add a binary
   sysfs interface to export the associated utility strings.

 - Add a sysfs attribute to control the IFCC handling in case of
   constant channel errors.

 - The vfio-ccw changes from Cornelia.

 - Bug fixes and cleanups.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (40 commits)
  s390/kvm: improve stack frame constants in entry.S
  s390/lpp: use assembler alternatives for the LPP instruction
  s390/entry.S: use assembler alternatives
  s390: add assembler macros for CPU alternatives
  s390: add sysfs attributes for spectre
  s390: report spectre mitigation via syslog
  s390: add automatic detection of the spectre defense
  s390: move nobp parameter functions to nospec-branch.c
  s390/cio: add util_string sysfs attribute
  s390/chsc: query utility strings via fmt3 channel path descriptor
  s390/cio: rename struct channel_path_desc
  s390/cio: fix unbind of io_subchannel_driver
  s390/qdio: split up CCQ handling for EQBS / SQBS
  s390/qdio: don't retry EQBS after CCQ 96
  s390/qdio: restrict buffer merging to eligible devices
  s390/qdio: don't merge ERROR output buffers
  s390/qdio: simplify math in get_*_buffer_frontier()
  s390/decompressor: trim uncompressed image head during the build
  s390/crypto: Fix kernel crash on aes_s390 module remove.
  s390/defkeymap: fix global init to zero
  ...

4 files changed, 78 insertions, 18 deletions

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index b5692a284bd8..04143c08bd6e 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -3918,8 +3918,13 @@ static int dasd_generic_requeue_all_requests(struct dasd_device *device)
 			cqr = refers;
 		}
 
-		if (cqr->block)
-			list_del_init(&cqr->blocklist);
+		/*
+		 * _dasd_requeue_request already checked for a valid
+		 * blockdevice, no need to check again
+		 * all erp requests (cqr->refers) have a cqr->block
+		 * pointer copy from the original cqr
+		 */
+		list_del_init(&cqr->blocklist);
 		cqr->block->base->discipline->free_cp(
 			cqr, (struct request *) cqr->callback_data);
 	}
diff --git a/drivers/s390/block/dasd_3990_erp.c b/drivers/s390/block/dasd_3990_erp.c
index ee14d8e45c97..ee73b0607e47 100644
--- a/drivers/s390/block/dasd_3990_erp.c
+++ b/drivers/s390/block/dasd_3990_erp.c
@@ -2214,15 +2214,28 @@ static void dasd_3990_erp_disable_path(struct dasd_device *device, __u8 lpum)
 {
 	int pos = pathmask_to_pos(lpum);
 
+	if (!(device->features & DASD_FEATURE_PATH_AUTODISABLE)) {
+		dev_err(&device->cdev->dev,
+			"Path %x.%02x (pathmask %02x) is operational despite excessive IFCCs\n",
+			device->path[pos].cssid, device->path[pos].chpid, lpum);
+		goto out;
+	}
+
 	/* no remaining path, cannot disable */
-	if (!(dasd_path_get_opm(device) & ~lpum))
-		return;
+	if (!(dasd_path_get_opm(device) & ~lpum)) {
+		dev_err(&device->cdev->dev,
+			"Last path %x.%02x (pathmask %02x) is operational despite excessive IFCCs\n",
+			device->path[pos].cssid, device->path[pos].chpid, lpum);
+		goto out;
+	}
 
 	dev_err(&device->cdev->dev,
 		"Path %x.%02x (pathmask %02x) is disabled - IFCC threshold exceeded\n",
 		device->path[pos].cssid, device->path[pos].chpid, lpum);
 	dasd_path_remove_opm(device, lpum);
 	dasd_path_add_ifccpm(device, lpum);
+
+out:
 	device->path[pos].errorclk = 0;
 	atomic_set(&device->path[pos].error_count, 0);
 }
diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
index e7cd28ff1984..b9ebb565ee2c 100644
--- a/drivers/s390/block/dasd_devmap.c
+++ b/drivers/s390/block/dasd_devmap.c
@@ -1550,9 +1550,49 @@ dasd_path_threshold_store(struct device *dev, struct device_attribute *attr,
 	dasd_put_device(device);
 	return count;
 }
-
 static DEVICE_ATTR(path_threshold, 0644, dasd_path_threshold_show,
 		   dasd_path_threshold_store);
+
+/*
+ * configure if path is disabled after IFCC/CCC error threshold is
+ * exceeded
+ */
+static ssize_t
+dasd_path_autodisable_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct dasd_devmap *devmap;
+	int flag;
+
+	devmap = dasd_find_busid(dev_name(dev));
+	if (!IS_ERR(devmap))
+		flag = (devmap->features & DASD_FEATURE_PATH_AUTODISABLE) != 0;
+	else
+		flag = (DASD_FEATURE_DEFAULT &
+			DASD_FEATURE_PATH_AUTODISABLE) != 0;
+	return snprintf(buf, PAGE_SIZE, flag ? "1\n" : "0\n");
+}
+
+static ssize_t
+dasd_path_autodisable_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+	unsigned int val;
+	int rc;
+
+	if (kstrtouint(buf, 0, &val) || val > 1)
+		return -EINVAL;
+
+	rc = dasd_set_feature(to_ccwdev(dev),
+			      DASD_FEATURE_PATH_AUTODISABLE, val);
+
+	return rc ? : count;
+}
+
+static DEVICE_ATTR(path_autodisable, 0644,
+		   dasd_path_autodisable_show,
+		   dasd_path_autodisable_store);
 /*
  * interval for IFCC/CCC checks
  * meaning time with no IFCC/CCC error before the error counter
@@ -1623,6 +1663,7 @@ static struct attribute * dasd_attrs[] = {
 	&dev_attr_host_access_count.attr,
 	&dev_attr_path_masks.attr,
 	&dev_attr_path_threshold.attr,
+	&dev_attr_path_autodisable.attr,
 	&dev_attr_path_interval.attr,
 	&dev_attr_path_reset.attr,
 	&dev_attr_hpf.attr,
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index 29397a9dba68..be208e7adcb4 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -214,24 +214,25 @@ static void set_ch_t(struct ch_t *geo, __u32 cyl, __u8 head)
 	geo->head |= head;
 }
 
-static int check_XRC(struct ccw1 *ccw, struct DE_eckd_data *data,
+static int set_timestamp(struct ccw1 *ccw, struct DE_eckd_data *data,
 		     struct dasd_device *device)
 {
 	struct dasd_eckd_private *private = device->private;
 	int rc;
 
-	if (!private->rdc_data.facilities.XRC_supported)
+	rc = get_phys_clock(&data->ep_sys_time);
+	/*
+	 * Ignore return code if XRC is not supported or
+	 * sync clock is switched off
+	 */
+	if ((rc && !private->rdc_data.facilities.XRC_supported) ||
+	    rc == -EOPNOTSUPP || rc == -EACCES)
 		return 0;
 
 	/* switch on System Time Stamp - needed for XRC Support */
 	data->ga_extended |= 0x08; /* switch on 'Time Stamp Valid'   */
 	data->ga_extended |= 0x02; /* switch on 'Extended Parameter' */
 
-	rc = get_phys_clock(&data->ep_sys_time);
-	/* Ignore return code if sync clock is switched off. */
-	if (rc == -EOPNOTSUPP || rc == -EACCES)
-		rc = 0;
-
 	if (ccw) {
 		ccw->count = sizeof(struct DE_eckd_data);
 		ccw->flags |= CCW_FLAG_SLI;
@@ -286,12 +287,12 @@ define_extent(struct ccw1 *ccw, struct DE_eckd_data *data, unsigned int trk,
 	case DASD_ECKD_CCW_WRITE_KD_MT:
 		data->mask.perm = 0x02;
 		data->attributes.operation = private->attrib.operation;
-		rc = check_XRC(ccw, data, device);
+		rc = set_timestamp(ccw, data, device);
 		break;
 	case DASD_ECKD_CCW_WRITE_CKD:
 	case DASD_ECKD_CCW_WRITE_CKD_MT:
 		data->attributes.operation = DASD_BYPASS_CACHE;
-		rc = check_XRC(ccw, data, device);
+		rc = set_timestamp(ccw, data, device);
 		break;
 	case DASD_ECKD_CCW_ERASE:
 	case DASD_ECKD_CCW_WRITE_HOME_ADDRESS:
@@ -299,7 +300,7 @@ define_extent(struct ccw1 *ccw, struct DE_eckd_data *data, unsigned int trk,
 		data->mask.perm = 0x3;
 		data->mask.auth = 0x1;
 		data->attributes.operation = DASD_BYPASS_CACHE;
-		rc = check_XRC(ccw, data, device);
+		rc = set_timestamp(ccw, data, device);
 		break;
 	case DASD_ECKD_CCW_WRITE_FULL_TRACK:
 		data->mask.perm = 0x03;
@@ -310,7 +311,7 @@ define_extent(struct ccw1 *ccw, struct DE_eckd_data *data, unsigned int trk,
 		data->mask.perm = 0x02;
 		data->attributes.operation = private->attrib.operation;
 		data->blk_size = blksize;
-		rc = check_XRC(ccw, data, device);
+		rc = set_timestamp(ccw, data, device);
 		break;
 	default:
 		dev_err(&device->cdev->dev,
@@ -993,7 +994,7 @@ static int dasd_eckd_read_conf(struct dasd_device *device)
 	struct dasd_eckd_private *private, path_private;
 	struct dasd_uid *uid;
 	char print_path_uid[60], print_device_uid[60];
-	struct channel_path_desc *chp_desc;
+	struct channel_path_desc_fmt0 *chp_desc;
 	struct subchannel_id sch_id;
 
 	private = device->private;
@@ -3440,7 +3441,7 @@ static int prepare_itcw(struct itcw *itcw,
 		dedata->mask.perm = 0x02;
 		dedata->attributes.operation = basepriv->attrib.operation;
 		dedata->blk_size = blksize;
-		rc = check_XRC(NULL, dedata, basedev);
+		rc = set_timestamp(NULL, dedata, basedev);
 		dedata->ga_extended |= 0x42;
 		lredata->operation.orientation = 0x0;
 		lredata->operation.operation = 0x3F;