[rocky8_10] History rebuild for kernel-4.18.0-553.58.1.el8_10

Makefile.rhelver

@@ -12,7 +12,7 @@ RHEL_MINOR = 10
 #
 # Use this spot to avoid future merge conflicts.
 # Do not trim this comment.
-RHEL_RELEASE = 553.56.1
+RHEL_RELEASE = 553.58.1
 
 #
 # ZSTREAM

arch/s390/include/asm/pci.h

@@ -123,6 +123,7 @@ struct zpci_dev {
 	struct kref kref;
 	struct hotplug_slot hotplug_slot;
 
+	struct mutex state_lock;	/* protect state changes */
 	enum zpci_state state;
 	u32		fid;		/* function ID, used by sclp */
 	u32		fh;		/* function handle, used by insn's */
@@ -146,7 +147,6 @@ struct zpci_dev {
 	u8		reserved	: 1;
 	unsigned int	devfn;		/* DEVFN part of the RID*/
 
-	struct mutex lock;
 	u8 pfip[CLP_PFIP_NR_SEGMENTS];	/* pci function internal path */
 	u32 uid;			/* user defined id */
 	u8 util_str[CLP_UTIL_STR_LEN];	/* utility string */
@@ -182,6 +182,7 @@ struct zpci_dev {
 	u64		dma_mask;	/* DMA address space mask */
 
 	/* Function measurement block */
+	struct mutex fmb_lock;
 	struct zpci_fmb *fmb;
 	u16		fmb_update;	/* update interval */
 	u16		fmb_length;

arch/s390/pci/pci.c

@@ -42,6 +42,7 @@
 /* list of all detected zpci devices */
 static LIST_HEAD(zpci_list);
 static DEFINE_SPINLOCK(zpci_list_lock);
+static DEFINE_MUTEX(zpci_add_remove_lock);
 
 static DECLARE_BITMAP(zpci_domain, ZPCI_DOMAIN_BITMAP_SIZE);
 static DEFINE_SPINLOCK(zpci_domain_lock);
@@ -67,6 +68,15 @@ EXPORT_SYMBOL_GPL(zpci_aipb);
 struct airq_iv *zpci_aif_sbv;
 EXPORT_SYMBOL_GPL(zpci_aif_sbv);
 
+void zpci_zdev_put(struct zpci_dev *zdev)
+{
+	if (!zdev)
+		return;
+	mutex_lock(&zpci_add_remove_lock);
+	kref_put_lock(&zdev->kref, zpci_release_device, &zpci_list_lock);
+	mutex_unlock(&zpci_add_remove_lock);
+}
+
 struct zpci_dev *get_zdev_by_fid(u32 fid)
 {
 	struct zpci_dev *tmp, *zdev = NULL;
@@ -808,12 +818,12 @@ EXPORT_SYMBOL_GPL(zpci_disable_device);
  * equivalent to its state during boot when first probing a driver.
  * Consequently after reset the PCI function requires re-initialization via the
  * common PCI code including re-enabling IRQs via pci_alloc_irq_vectors()
- * and enabling the function via e.g.pci_enablde_device_flags().The caller
+ * and enabling the function via e.g. pci_enable_device_flags(). The caller
  * must guard against concurrent reset attempts.
  *
  * In most cases this function should not be called directly but through
  * pci_reset_function() or pci_reset_bus() which handle the save/restore and
- * locking.
+ * locking - asserted by lockdep.
  *
  * Return: 0 on success and an error value otherwise
  */
@@ -822,6 +832,7 @@ int zpci_hot_reset_device(struct zpci_dev *zdev)
 	u8 status;
 	int rc;
 
+	lockdep_assert_held(&zdev->state_lock);
 	zpci_dbg(3, "rst fid:%x, fh:%x\n", zdev->fid, zdev->fh);
 	if (zdev_enabled(zdev)) {
 		/* Disables device access, DMAs and IRQs (reset state) */
@@ -885,7 +896,8 @@ struct zpci_dev *zpci_create_device(u32 fid, u32 fh, enum zpci_state state)
 		goto error;
 	zdev->state =  state;
 
-	mutex_init(&zdev->lock);
+	mutex_init(&zdev->state_lock);
+	mutex_init(&zdev->fmb_lock);
 	mutex_init(&zdev->kzdev_lock);
 
 	return zdev;
@@ -911,6 +923,7 @@ int zpci_add_device(struct zpci_dev *zdev)
 {
 	int rc;
 
+	mutex_lock(&zpci_add_remove_lock);
 	zpci_dbg(1, "add fid:%x, fh:%x, c:%d\n", zdev->fid, zdev->fh, zdev->state);
 	rc = zpci_init_iommu(zdev);
 	if (rc)
@@ -924,12 +937,14 @@ int zpci_add_device(struct zpci_dev *zdev)
 	spin_lock(&zpci_list_lock);
 	list_add_tail(&zdev->entry, &zpci_list);
 	spin_unlock(&zpci_list_lock);
+	mutex_unlock(&zpci_add_remove_lock);
 	return 0;
 
 error_destroy_iommu:
 	zpci_destroy_iommu(zdev);
 error:
 	zpci_dbg(0, "add fid:%x, rc:%d\n", zdev->fid, rc);
+	mutex_unlock(&zpci_add_remove_lock);
 	return rc;
 }
 
@@ -946,23 +961,20 @@ bool zpci_is_device_configured(struct zpci_dev *zdev)
  * @zdev: the zpci_dev that was reserved
  *
  * Handle the case that a given zPCI function was reserved by another system.
- * After a call to this function the zpci_dev can not be found via
- * get_zdev_by_fid() anymore but may still be accessible via existing
- * references though it will not be functional anymore.
  */
 void zpci_device_reserved(struct zpci_dev *zdev)
 {
-	if (zdev->has_hp_slot)
-		zpci_exit_slot(zdev);
-	/*
-	 * Remove device from zpci_list as it is going away. This also
-	 * makes sure we ignore subsequent zPCI events for this device.
-	 */
-	spin_lock(&zpci_list_lock);
-	list_del(&zdev->entry);
-	spin_unlock(&zpci_list_lock);
+	lockdep_assert_held(&zdev->state_lock);
+	/* We may declare the device reserved multiple times */
+	if (zdev->state == ZPCI_FN_STATE_RESERVED)
+		return;
 	zdev->state = ZPCI_FN_STATE_RESERVED;
 	zpci_dbg(3, "rsv fid:%x\n", zdev->fid);
+	/*
+	 * The underlying device is gone. Allow the zdev to be freed
+	 * as soon as all other references are gone by accounting for
+	 * the removal as a dropped reference.
+	 */
 	zpci_zdev_put(zdev);
 }
 
@@ -997,6 +1009,10 @@ int zpci_deconfigure_device(struct zpci_dev *zdev)
 {
 	int rc;
 
+	lockdep_assert_held(&zdev->state_lock);
+	if (zdev->state != ZPCI_FN_STATE_CONFIGURED)
+		return 0;
+
 	if (zdev->zbus->bus)
 		zpci_bus_remove_device(zdev, false);
 
@@ -1023,39 +1039,24 @@ int zpci_deconfigure_device(struct zpci_dev *zdev)
 void zpci_release_device(struct kref *kref)
 {
 	struct zpci_dev *zdev = container_of(kref, struct zpci_dev, kref);
-	int ret;
 
-	if (zdev->zbus->bus)
-		zpci_bus_remove_device(zdev, false);
+	lockdep_assert_held(&zpci_add_remove_lock);
+	WARN_ON(zdev->state != ZPCI_FN_STATE_RESERVED);
+	/*
+	 * We already hold zpci_list_lock thanks to kref_put_lock().
+	 * This makes sure no new reference can be taken from the list.
+	 */
+	list_del(&zdev->entry);
+	spin_unlock(&zpci_list_lock);
 
-	if (zdev->dma_table)
-		zpci_dma_exit_device(zdev);
-	if (zdev_enabled(zdev))
-		zpci_disable_device(zdev);
+	if (zdev->has_hp_slot)
+		zpci_exit_slot(zdev);
 
-	switch (zdev->state) {
-	case ZPCI_FN_STATE_CONFIGURED:
-		ret = sclp_pci_deconfigure(zdev->fid);
-		zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, ret);
-		fallthrough;
-	case ZPCI_FN_STATE_STANDBY:
-		if (zdev->has_hp_slot)
-			zpci_exit_slot(zdev);
-		spin_lock(&zpci_list_lock);
-		list_del(&zdev->entry);
-		spin_unlock(&zpci_list_lock);
-		zpci_dbg(3, "rsv fid:%x\n", zdev->fid);
-		fallthrough;
-	case ZPCI_FN_STATE_RESERVED:
-		if (zdev->has_resources)
-			zpci_cleanup_bus_resources(zdev);
-		zpci_bus_device_unregister(zdev);
-		zpci_destroy_iommu(zdev);
-		/* fallthrough */
-	default:
-		break;
-	}
+	if (zdev->has_resources)
+		zpci_cleanup_bus_resources(zdev);
 
+	zpci_bus_device_unregister(zdev);
+	zpci_destroy_iommu(zdev);
 	zpci_dbg(3, "rem fid:%x\n", zdev->fid);
 	kfree(zdev);
 }

arch/s390/pci/pci_bus.h

@@ -17,11 +17,8 @@ int zpci_bus_scan_device(struct zpci_dev *zdev);
 void zpci_bus_remove_device(struct zpci_dev *zdev, bool set_error);
 
 void zpci_release_device(struct kref *kref);
-static inline void zpci_zdev_put(struct zpci_dev *zdev)
-{
-	if (zdev)
-		kref_put(&zdev->kref, zpci_release_device);
-}
+
+void zpci_zdev_put(struct zpci_dev *zdev);
 
 static inline void zpci_zdev_get(struct zpci_dev *zdev)
 {

arch/s390/pci/pci_clp.c

@@ -421,6 +421,8 @@ static void __clp_add(struct clp_fh_list_entry *entry, void *data)
 		return;
 	}
 	zdev = zpci_create_device(entry->fid, entry->fh, entry->config_state);
+	if (IS_ERR(zdev))
+		return;
 	list_add_tail(&zdev->entry, scan_list);
 }
 

arch/s390/pci/pci_debug.c

@@ -85,9 +85,9 @@ static int pci_perf_show(struct seq_file *m, void *v)
 	if (!zdev)
 		return 0;
 
-	mutex_lock(&zdev->lock);
+	mutex_lock(&zdev->fmb_lock);
 	if (!zdev->fmb) {
-		mutex_unlock(&zdev->lock);
+		mutex_unlock(&zdev->fmb_lock);
 		seq_puts(m, "FMB statistics disabled\n");
 		return 0;
 	}
@@ -124,7 +124,7 @@ static int pci_perf_show(struct seq_file *m, void *v)
 	}
 
 	pci_sw_counter_show(m);
-	mutex_unlock(&zdev->lock);
+	mutex_unlock(&zdev->fmb_lock);
 	return 0;
 }
 
@@ -142,7 +142,7 @@ static ssize_t pci_perf_seq_write(struct file *file, const char __user *ubuf,
 	if (rc)
 		return rc;
 
-	mutex_lock(&zdev->lock);
+	mutex_lock(&zdev->fmb_lock);
 	switch (val) {
 	case 0:
 		rc = zpci_fmb_disable_device(zdev);
@@ -151,7 +151,7 @@ static ssize_t pci_perf_seq_write(struct file *file, const char __user *ubuf,
 		rc = zpci_fmb_enable_device(zdev);
 		break;
 	}
-	mutex_unlock(&zdev->lock);
+	mutex_unlock(&zdev->fmb_lock);
 	return rc ? rc : count;
 }
 

arch/s390/pci/pci_event.c

@@ -260,6 +260,7 @@ static void __zpci_event_error(struct zpci_ccdf_err *ccdf)
 	zpci_err_hex(ccdf, sizeof(*ccdf));
 
 	if (zdev) {
+		mutex_lock(&zdev->state_lock);
 		zpci_update_fh(zdev, ccdf->fh);
 		if (zdev->zbus->bus)
 			pdev = pci_get_slot(zdev->zbus->bus, zdev->devfn);
@@ -288,6 +289,8 @@ static void __zpci_event_error(struct zpci_ccdf_err *ccdf)
 	}
 	pci_dev_put(pdev);
 no_pdev:
+	if (zdev)
+		mutex_unlock(&zdev->state_lock);
 	zpci_zdev_put(zdev);
 }
 
@@ -314,6 +317,22 @@ static void zpci_event_hard_deconfigured(struct zpci_dev *zdev, u32 fh)
 	zdev->state = ZPCI_FN_STATE_STANDBY;
 }
 
+static void zpci_event_reappear(struct zpci_dev *zdev)
+{
+	lockdep_assert_held(&zdev->state_lock);
+	/*
+	 * The zdev is in the reserved state. This means that it was presumed to
+	 * go away but there are still undropped references. Now, the platform
+	 * announced its availability again. Bring back the lingering zdev
+	 * to standby. This is safe because we hold a temporary reference
+	 * now so that it won't go away. Account for the re-appearance of the
+	 * underlying device by incrementing the reference count.
+	 */
+	zdev->state = ZPCI_FN_STATE_STANDBY;
+	zpci_zdev_get(zdev);
+	zpci_dbg(1, "rea fid:%x, fh:%x\n", zdev->fid, zdev->fh);
+}
+
 static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf)
 {
 	struct zpci_dev *zdev = get_zdev_by_fid(ccdf->fid);
@@ -322,6 +341,10 @@ static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf)
 
 	zpci_dbg(3, "avl fid:%x, fh:%x, pec:%x\n",
 		 ccdf->fid, ccdf->fh, ccdf->pec);
+
+	if (existing_zdev)
+		mutex_lock(&zdev->state_lock);
+
 	switch (ccdf->pec) {
 	case 0x0301: /* Reserved|Standby -> Configured */
 		if (!zdev) {
@@ -333,8 +356,10 @@ static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf)
 				break;
 			}
 		} else {
+			if (zdev->state == ZPCI_FN_STATE_RESERVED)
+				zpci_event_reappear(zdev);
 			/* the configuration request may be stale */
-			if (zdev->state != ZPCI_FN_STATE_STANDBY)
+			else if (zdev->state != ZPCI_FN_STATE_STANDBY)
 				break;
 			zdev->state = ZPCI_FN_STATE_CONFIGURED;
 		}
@@ -350,6 +375,8 @@ static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf)
 				break;
 			}
 		} else {
+			if (zdev->state == ZPCI_FN_STATE_RESERVED)
+				zpci_event_reappear(zdev);
 			zpci_update_fh(zdev, ccdf->fh);
 		}
 		break;
@@ -390,8 +417,10 @@ static void __zpci_event_availability(struct zpci_ccdf_avail *ccdf)
 	default:
 		break;
 	}
-	if (existing_zdev)
+	if (existing_zdev) {
+		mutex_unlock(&zdev->state_lock);
 		zpci_zdev_put(zdev);
+	}
 }
 
 void zpci_event_availability(void *data)