This is the 4.9.157 stable release

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Merge 4.9.157 into android-4.9

Changes in 4.9.157
	mtd: rawnand: gpmi: fix MX28 bus master lockup problem
	iio: chemical: atlas-ph-sensor: correct IIO_TEMP values to millicelsius
	signal: Always notice exiting tasks
	signal: Better detection of synchronous signals
	misc: vexpress: Off by one in vexpress_syscfg_exec()
	samples: mei: use /dev/mei0 instead of /dev/mei
	debugfs: fix debugfs_rename parameter checking
	mips: cm: reprime error cause
	MIPS: OCTEON: don't set octeon_dma_bar_type if PCI is disabled
	MIPS: VDSO: Include $(ccflags-vdso) in o32,n32 .lds builds
	ARM: iop32x/n2100: fix PCI IRQ mapping
	ARM: tango: Improve ARCH_MULTIPLATFORM compatibility
	mac80211: ensure that mgmt tx skbs have tailroom for encryption
	drm/modes: Prevent division by zero htotal
	drm/vmwgfx: Fix setting of dma masks
	drm/vmwgfx: Return error code from vmw_execbuf_copy_fence_user
	nfsd4: fix cached replies to solo SEQUENCE compounds
	nfsd4: catch some false session retries
	HID: debug: fix the ring buffer implementation
	Revert "cifs: In Kconfig CONFIG_CIFS_POSIX needs depends on legacy (insecure cifs)"
	libceph: avoid KEEPALIVE_PENDING races in ceph_con_keepalive()
	xfrm: refine validation of template and selector families
	batman-adv: Avoid WARN on net_device without parent in netns
	batman-adv: Force mac header to start of data on xmit
	Linux 4.9.157

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

Makefile

@@ -1,6 +1,6 @@
 VERSION = 4
 PATCHLEVEL = 9
-SUBLEVEL = 156
+SUBLEVEL = 157
 EXTRAVERSION =
 NAME = Roaring Lionus
 

arch/arm/mach-iop32x/n2100.c

@@ -75,8 +75,7 @@ void __init n2100_map_io(void)
 /*
  * N2100 PCI.
  */
-static int __init
-n2100_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+static int n2100_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
 {
 	int irq;
 

arch/arm/mach-tango/pm.c

@@ -2,6 +2,7 @@
 #include <linux/suspend.h>
 #include <asm/suspend.h>
 #include "smc.h"
+#include "pm.h"
 
 static int tango_pm_powerdown(unsigned long arg)
 {
@@ -23,10 +24,7 @@ static const struct platform_suspend_ops tango_pm_ops = {
 	.valid = suspend_valid_only_mem,
 };
 
-static int __init tango_pm_init(void)
+void __init tango_pm_init(void)
 {
 	suspend_set_ops(&tango_pm_ops);
-	return 0;
 }
-
-late_initcall(tango_pm_init);

arch/arm/mach-tango/pm.h

@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifdef CONFIG_SUSPEND
+void __init tango_pm_init(void);
+#else
+#define tango_pm_init NULL
+#endif

arch/arm/mach-tango/setup.c

@@ -1,6 +1,7 @@
 #include <asm/mach/arch.h>
 #include <asm/hardware/cache-l2x0.h>
 #include "smc.h"
+#include "pm.h"
 
 static void tango_l2c_write(unsigned long val, unsigned int reg)
 {
@@ -14,4 +15,5 @@ DT_MACHINE_START(TANGO_DT, "Sigma Tango DT")
 	.dt_compat	= tango_dt_compat,
 	.l2c_aux_mask	= ~0,
 	.l2c_write_sec	= tango_l2c_write,
+	.init_late	= tango_pm_init,
 MACHINE_END

arch/mips/kernel/mips-cm.c

@@ -424,5 +424,5 @@ void mips_cm_error_report(void)
 	}
 
 	/* reprime cause register */
-	write_gcr_error_cause(0);
+	write_gcr_error_cause(cm_error);
 }

arch/mips/pci/pci-octeon.c

@@ -573,6 +573,11 @@ static int __init octeon_pci_setup(void)
 	if (octeon_has_feature(OCTEON_FEATURE_PCIE))
 		return 0;
 
+	if (!octeon_is_pci_host()) {
+		pr_notice("Not in host mode, PCI Controller not initialized\n");
+		return 0;
+	}
+
 	/* Point pcibios_map_irq() to the PCI version of it */
 	octeon_pcibios_map_irq = octeon_pci_pcibios_map_irq;
 
@@ -584,11 +589,6 @@ static int __init octeon_pci_setup(void)
 	else
 		octeon_dma_bar_type = OCTEON_DMA_BAR_TYPE_BIG;
 
-	if (!octeon_is_pci_host()) {
-		pr_notice("Not in host mode, PCI Controller not initialized\n");
-		return 0;
-	}
-
 	/* PCI I/O and PCI MEM values */
 	set_io_port_base(OCTEON_PCI_IOSPACE_BASE);
 	ioport_resource.start = 0;

arch/mips/vdso/Makefile

@@ -116,7 +116,7 @@ $(obj)/%-o32.o: $(src)/%.c FORCE
 	$(call cmd,force_checksrc)
 	$(call if_changed_rule,cc_o_c)
 
-$(obj)/vdso-o32.lds: KBUILD_CPPFLAGS := -mabi=32
+$(obj)/vdso-o32.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) -mabi=32
 $(obj)/vdso-o32.lds: $(src)/vdso.lds.S FORCE
 	$(call if_changed_dep,cpp_lds_S)
 
@@ -156,7 +156,7 @@ $(obj)/%-n32.o: $(src)/%.c FORCE
 	$(call cmd,force_checksrc)
 	$(call if_changed_rule,cc_o_c)
 
-$(obj)/vdso-n32.lds: KBUILD_CPPFLAGS := -mabi=n32
+$(obj)/vdso-n32.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) -mabi=n32
 $(obj)/vdso-n32.lds: $(src)/vdso.lds.S FORCE
 	$(call if_changed_dep,cpp_lds_S)
 

drivers/gpu/drm/drm_modes.c

@@ -753,7 +753,7 @@ int drm_mode_hsync(const struct drm_display_mode *mode)
 	if (mode->hsync)
 		return mode->hsync;
 
-	if (mode->htotal < 0)
+	if (mode->htotal <= 0)
 		return 0;
 
 	calc_val = (mode->clock * 1000) / mode->htotal; /* hsync in Hz */

drivers/gpu/drm/vmwgfx/vmwgfx_drv.c

@@ -605,13 +605,16 @@ out_fixup:
 static int vmw_dma_masks(struct vmw_private *dev_priv)
 {
 	struct drm_device *dev = dev_priv->dev;
+	int ret = 0;
 
-	if (intel_iommu_enabled &&
+	ret = dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(64));
+	if (dev_priv->map_mode != vmw_dma_phys &&
 	    (sizeof(unsigned long) == 4 || vmw_restrict_dma_mask)) {
 		DRM_INFO("Restricting DMA addresses to 44 bits.\n");
-		return dma_set_mask(dev->dev, DMA_BIT_MASK(44));
+		return dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(44));
 	}
-	return 0;
+
+	return ret;
 }
 #else
 static int vmw_dma_masks(struct vmw_private *dev_priv)

drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c

@@ -3769,7 +3769,7 @@ int vmw_execbuf_fence_commands(struct drm_file *file_priv,
 		*p_fence = NULL;
 	}
 
-	return 0;
+	return ret;
 }
 
 /**

drivers/hid/hid-debug.c

@@ -30,6 +30,7 @@
 
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
+#include <linux/kfifo.h>
 #include <linux/sched.h>
 #include <linux/export.h>
 #include <linux/slab.h>
@@ -455,7 +456,7 @@ static char *resolv_usage_page(unsigned page, struct seq_file *f) {
 	char *buf = NULL;
 
 	if (!f) {
-		buf = kzalloc(sizeof(char) * HID_DEBUG_BUFSIZE, GFP_ATOMIC);
+		buf = kzalloc(HID_DEBUG_BUFSIZE, GFP_ATOMIC);
 		if (!buf)
 			return ERR_PTR(-ENOMEM);
 	}
@@ -659,17 +660,12 @@ EXPORT_SYMBOL_GPL(hid_dump_device);
 /* enqueue string to 'events' ring buffer */
 void hid_debug_event(struct hid_device *hdev, char *buf)
 {
-	unsigned i;
 	struct hid_debug_list *list;
 	unsigned long flags;
 
 	spin_lock_irqsave(&hdev->debug_list_lock, flags);
-	list_for_each_entry(list, &hdev->debug_list, node) {
-		for (i = 0; buf[i]; i++)
-			list->hid_debug_buf[(list->tail + i) % HID_DEBUG_BUFSIZE] =
-				buf[i];
-		list->tail = (list->tail + i) % HID_DEBUG_BUFSIZE;
-        }
+	list_for_each_entry(list, &hdev->debug_list, node)
+		kfifo_in(&list->hid_debug_fifo, buf, strlen(buf));
 	spin_unlock_irqrestore(&hdev->debug_list_lock, flags);
 
 	wake_up_interruptible(&hdev->debug_wait);
@@ -720,8 +716,7 @@ void hid_dump_input(struct hid_device *hdev, struct hid_usage *usage, __s32 valu
 	hid_debug_event(hdev, buf);
 
 	kfree(buf);
-        wake_up_interruptible(&hdev->debug_wait);
-
+	wake_up_interruptible(&hdev->debug_wait);
 }
 EXPORT_SYMBOL_GPL(hid_dump_input);
 
@@ -1086,8 +1081,8 @@ static int hid_debug_events_open(struct inode *inode, struct file *file)
 		goto out;
 	}
 
-	if (!(list->hid_debug_buf = kzalloc(sizeof(char) * HID_DEBUG_BUFSIZE, GFP_KERNEL))) {
-		err = -ENOMEM;
+	err = kfifo_alloc(&list->hid_debug_fifo, HID_DEBUG_FIFOSIZE, GFP_KERNEL);
+	if (err) {
 		kfree(list);
 		goto out;
 	}
@@ -1107,77 +1102,57 @@ static ssize_t hid_debug_events_read(struct file *file, char __user *buffer,
 		size_t count, loff_t *ppos)
 {
 	struct hid_debug_list *list = file->private_data;
-	int ret = 0, len;
+	int ret = 0, copied;
 	DECLARE_WAITQUEUE(wait, current);
 
 	mutex_lock(&list->read_mutex);
-	while (ret == 0) {
-		if (list->head == list->tail) {
-			add_wait_queue(&list->hdev->debug_wait, &wait);
-			set_current_state(TASK_INTERRUPTIBLE);
+	if (kfifo_is_empty(&list->hid_debug_fifo)) {
+		add_wait_queue(&list->hdev->debug_wait, &wait);
+		set_current_state(TASK_INTERRUPTIBLE);
 
-			while (list->head == list->tail) {
-				if (file->f_flags & O_NONBLOCK) {
-					ret = -EAGAIN;
-					break;
-				}
-				if (signal_pending(current)) {
-					ret = -ERESTARTSYS;
-					break;
-				}
-
-				if (!list->hdev || !list->hdev->debug) {
-					ret = -EIO;
-					set_current_state(TASK_RUNNING);
-					goto out;
-				}
-
-				/* allow O_NONBLOCK from other threads */
-				mutex_unlock(&list->read_mutex);
-				schedule();
-				mutex_lock(&list->read_mutex);
-				set_current_state(TASK_INTERRUPTIBLE);
+		while (kfifo_is_empty(&list->hid_debug_fifo)) {
+			if (file->f_flags & O_NONBLOCK) {
+				ret = -EAGAIN;
+				break;
 			}
 
-			set_current_state(TASK_RUNNING);
-			remove_wait_queue(&list->hdev->debug_wait, &wait);
+			if (signal_pending(current)) {
+				ret = -ERESTARTSYS;
+				break;
+			}
+
+			/* if list->hdev is NULL we cannot remove_wait_queue().
+			 * if list->hdev->debug is 0 then hid_debug_unregister()
+			 * was already called and list->hdev is being destroyed.
+			 * if we add remove_wait_queue() here we can hit a race.
+			 */
+			if (!list->hdev || !list->hdev->debug) {
+				ret = -EIO;
+				set_current_state(TASK_RUNNING);
+				goto out;
+			}
+
+			/* allow O_NONBLOCK from other threads */
+			mutex_unlock(&list->read_mutex);
+			schedule();
+			mutex_lock(&list->read_mutex);
+			set_current_state(TASK_INTERRUPTIBLE);
 		}
 
+		__set_current_state(TASK_RUNNING);
+		remove_wait_queue(&list->hdev->debug_wait, &wait);
+
 		if (ret)
 			goto out;
-
-		/* pass the ringbuffer contents to userspace */
-copy_rest:
-		if (list->tail == list->head)
-			goto out;
-		if (list->tail > list->head) {
-			len = list->tail - list->head;
-			if (len > count)
-				len = count;
-
-			if (copy_to_user(buffer + ret, &list->hid_debug_buf[list->head], len)) {
-				ret = -EFAULT;
-				goto out;
-			}
-			ret += len;
-			list->head += len;
-		} else {
-			len = HID_DEBUG_BUFSIZE - list->head;
-			if (len > count)
-				len = count;
-
-			if (copy_to_user(buffer, &list->hid_debug_buf[list->head], len)) {
-				ret = -EFAULT;
-				goto out;
-			}
-			list->head = 0;
-			ret += len;
-			count -= len;
-			if (count > 0)
-				goto copy_rest;
-		}
-
 	}
+
+	/* pass the fifo content to userspace, locking is not needed with only
+	 * one concurrent reader and one concurrent writer
+	 */
+	ret = kfifo_to_user(&list->hid_debug_fifo, buffer, count, &copied);
+	if (ret)
+		goto out;
+	ret = copied;
 out:
 	mutex_unlock(&list->read_mutex);
 	return ret;
@@ -1188,7 +1163,7 @@ static unsigned int hid_debug_events_poll(struct file *file, poll_table *wait)
 	struct hid_debug_list *list = file->private_data;
 
 	poll_wait(file, &list->hdev->debug_wait, wait);
-	if (list->head != list->tail)
+	if (!kfifo_is_empty(&list->hid_debug_fifo))
 		return POLLIN | POLLRDNORM;
 	if (!list->hdev->debug)
 		return POLLERR | POLLHUP;
@@ -1203,7 +1178,7 @@ static int hid_debug_events_release(struct inode *inode, struct file *file)
 	spin_lock_irqsave(&list->hdev->debug_list_lock, flags);
 	list_del(&list->node);
 	spin_unlock_irqrestore(&list->hdev->debug_list_lock, flags);
-	kfree(list->hid_debug_buf);
+	kfifo_free(&list->hid_debug_fifo);
 	kfree(list);
 
 	return 0;
@@ -1254,4 +1229,3 @@ void hid_debug_exit(void)
 {
 	debugfs_remove_recursive(hid_debug_root);
 }
-

drivers/iio/chemical/atlas-ph-sensor.c

@@ -453,9 +453,8 @@ static int atlas_read_raw(struct iio_dev *indio_dev,
 	case IIO_CHAN_INFO_SCALE:
 		switch (chan->type) {
 		case IIO_TEMP:
-			*val = 1; /* 0.01 */
-			*val2 = 100;
-			break;
+			*val = 10;
+			return IIO_VAL_INT;
 		case IIO_PH:
 			*val = 1; /* 0.001 */
 			*val2 = 1000;
@@ -486,7 +485,7 @@ static int atlas_write_raw(struct iio_dev *indio_dev,
 			   int val, int val2, long mask)
 {
 	struct atlas_data *data = iio_priv(indio_dev);
-	__be32 reg = cpu_to_be32(val);
+	__be32 reg = cpu_to_be32(val / 10);
 
 	if (val2 != 0 || val < 0 || val > 20000)
 		return -EINVAL;

drivers/misc/vexpress-syscfg.c

@@ -61,7 +61,7 @@ static int vexpress_syscfg_exec(struct vexpress_syscfg_func *func,
 	int tries;
 	long timeout;
 
-	if (WARN_ON(index > func->num_templates))
+	if (WARN_ON(index >= func->num_templates))
 		return -EINVAL;
 
 	command = readl(syscfg->base + SYS_CFGCTRL);

drivers/mtd/nand/gpmi-nand/gpmi-lib.c

@@ -168,9 +168,10 @@ int gpmi_init(struct gpmi_nand_data *this)
 
 	/*
 	 * Reset BCH here, too. We got failures otherwise :(
-	 * See later BCH reset for explanation of MX23 handling
+	 * See later BCH reset for explanation of MX23 and MX28 handling
 	 */
-	ret = gpmi_reset_block(r->bch_regs, GPMI_IS_MX23(this));
+	ret = gpmi_reset_block(r->bch_regs,
+			       GPMI_IS_MX23(this) || GPMI_IS_MX28(this));
 	if (ret)
 		goto err_out;
 
@@ -275,13 +276,11 @@ int bch_set_geometry(struct gpmi_nand_data *this)
 
 	/*
 	* Due to erratum #2847 of the MX23, the BCH cannot be soft reset on this
-	* chip, otherwise it will lock up. So we skip resetting BCH on the MX23.
-	* On the other hand, the MX28 needs the reset, because one case has been
-	* seen where the BCH produced ECC errors constantly after 10000
-	* consecutive reboots. The latter case has not been seen on the MX23
-	* yet, still we don't know if it could happen there as well.
+	* chip, otherwise it will lock up. So we skip resetting BCH on the MX23
+	* and MX28.
 	*/
-	ret = gpmi_reset_block(r->bch_regs, GPMI_IS_MX23(this));
+	ret = gpmi_reset_block(r->bch_regs,
+			       GPMI_IS_MX23(this) || GPMI_IS_MX28(this));
 	if (ret)
 		goto err_out;
 

fs/cifs/Kconfig

@@ -111,7 +111,7 @@ config CIFS_XATTR
 
 config CIFS_POSIX
         bool "CIFS POSIX Extensions"
-        depends on CIFS && CIFS_ALLOW_INSECURE_LEGACY && CIFS_XATTR
+        depends on CIFS_XATTR
         help
           Enabling this option will cause the cifs client to attempt to
 	  negotiate a newer dialect with servers, such as Samba 3.0.5

fs/debugfs/inode.c

@@ -732,6 +732,13 @@ struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
 	struct dentry *dentry = NULL, *trap;
 	struct name_snapshot old_name;
 
+	if (IS_ERR(old_dir))
+		return old_dir;
+	if (IS_ERR(new_dir))
+		return new_dir;
+	if (IS_ERR_OR_NULL(old_dentry))
+		return old_dentry;
+
 	trap = lock_rename(new_dir, old_dir);
 	/* Source or destination directories don't exist? */
 	if (d_really_is_negative(old_dir) || d_really_is_negative(new_dir))

fs/nfsd/nfs4state.c

@@ -1472,8 +1472,10 @@ free_session_slots(struct nfsd4_session *ses)
 {
 	int i;
 
-	for (i = 0; i < ses->se_fchannel.maxreqs; i++)
+	for (i = 0; i < ses->se_fchannel.maxreqs; i++) {
+		free_svc_cred(&ses->se_slots[i]->sl_cred);
 		kfree(ses->se_slots[i]);
+	}
 }
 
 /*
@@ -2344,14 +2346,18 @@ nfsd4_store_cache_entry(struct nfsd4_compoundres *resp)
 
 	dprintk("--> %s slot %p\n", __func__, slot);
 
+	slot->sl_flags |= NFSD4_SLOT_INITIALIZED;
 	slot->sl_opcnt = resp->opcnt;
 	slot->sl_status = resp->cstate.status;
+	free_svc_cred(&slot->sl_cred);
+	copy_cred(&slot->sl_cred, &resp->rqstp->rq_cred);
 
-	slot->sl_flags |= NFSD4_SLOT_INITIALIZED;
-	if (nfsd4_not_cached(resp)) {
-		slot->sl_datalen = 0;
+	if (!nfsd4_cache_this(resp)) {
+		slot->sl_flags &= ~NFSD4_SLOT_CACHED;
 		return;
 	}
+	slot->sl_flags |= NFSD4_SLOT_CACHED;
+
 	base = resp->cstate.data_offset;
 	slot->sl_datalen = buf->len - base;
 	if (read_bytes_from_xdr_buf(buf, base, slot->sl_data, slot->sl_datalen))
@@ -2378,8 +2384,16 @@ nfsd4_enc_sequence_replay(struct nfsd4_compoundargs *args,
 	op = &args->ops[resp->opcnt - 1];
 	nfsd4_encode_operation(resp, op);
 
-	/* Return nfserr_retry_uncached_rep in next operation. */
-	if (args->opcnt > 1 && !(slot->sl_flags & NFSD4_SLOT_CACHETHIS)) {
+	if (slot->sl_flags & NFSD4_SLOT_CACHED)
+		return op->status;
+	if (args->opcnt == 1) {
+		/*
+		 * The original operation wasn't a solo sequence--we
+		 * always cache those--so this retry must not match the
+		 * original:
+		 */
+		op->status = nfserr_seq_false_retry;
+	} else {
 		op = &args->ops[resp->opcnt++];
 		op->status = nfserr_retry_uncached_rep;
 		nfsd4_encode_operation(resp, op);
@@ -3039,6 +3053,34 @@ static bool nfsd4_request_too_big(struct svc_rqst *rqstp,
 	return xb->len > session->se_fchannel.maxreq_sz;
 }
 
+static bool replay_matches_cache(struct svc_rqst *rqstp,
+		 struct nfsd4_sequence *seq, struct nfsd4_slot *slot)
+{
+	struct nfsd4_compoundargs *argp = rqstp->rq_argp;
+
+	if ((bool)(slot->sl_flags & NFSD4_SLOT_CACHETHIS) !=
+	    (bool)seq->cachethis)
+		return false;
+	/*
+	 * If there's an error than the reply can have fewer ops than
+	 * the call.  But if we cached a reply with *more* ops than the
+	 * call you're sending us now, then this new call is clearly not
+	 * really a replay of the old one:
+	 */
+	if (slot->sl_opcnt < argp->opcnt)
+		return false;
+	/* This is the only check explicitly called by spec: */
+	if (!same_creds(&rqstp->rq_cred, &slot->sl_cred))
+		return false;
+	/*
+	 * There may be more comparisons we could actually do, but the
+	 * spec doesn't require us to catch every case where the calls
+	 * don't match (that would require caching the call as well as
+	 * the reply), so we don't bother.
+	 */
+	return true;
+}
+
 __be32
 nfsd4_sequence(struct svc_rqst *rqstp,
 	       struct nfsd4_compound_state *cstate,
@@ -3098,6 +3140,9 @@ nfsd4_sequence(struct svc_rqst *rqstp,
 		status = nfserr_seq_misordered;
 		if (!(slot->sl_flags & NFSD4_SLOT_INITIALIZED))
 			goto out_put_session;
+		status = nfserr_seq_false_retry;
+		if (!replay_matches_cache(rqstp, seq, slot))
+			goto out_put_session;
 		cstate->slot = slot;
 		cstate->session = session;
 		cstate->clp = clp;

fs/nfsd/state.h

@@ -169,11 +169,13 @@ static inline struct nfs4_delegation *delegstateid(struct nfs4_stid *s)
 struct nfsd4_slot {
 	u32	sl_seqid;
 	__be32	sl_status;
+	struct svc_cred sl_cred;
 	u32	sl_datalen;
 	u16	sl_opcnt;
 #define NFSD4_SLOT_INUSE	(1 << 0)
 #define NFSD4_SLOT_CACHETHIS	(1 << 1)
 #define NFSD4_SLOT_INITIALIZED	(1 << 2)
+#define NFSD4_SLOT_CACHED	(1 << 3)
 	u8	sl_flags;
 	char	sl_data[];
 };

fs/nfsd/xdr4.h

@@ -645,9 +645,18 @@ static inline bool nfsd4_is_solo_sequence(struct nfsd4_compoundres *resp)
 	return resp->opcnt == 1 && args->ops[0].opnum == OP_SEQUENCE;
 }
 
-static inline bool nfsd4_not_cached(struct nfsd4_compoundres *resp)
+/*
+ * The session reply cache only needs to cache replies that the client
+ * actually asked us to.  But it's almost free for us to cache compounds
+ * consisting of only a SEQUENCE op, so we may as well cache those too.
+ * Also, the protocol doesn't give us a convenient response in the case
+ * of a replay of a solo SEQUENCE op that wasn't cached
+ * (RETRY_UNCACHED_REP can only be returned in the second op of a
+ * compound).
+ */
+static inline bool nfsd4_cache_this(struct nfsd4_compoundres *resp)
 {
-	return !(resp->cstate.slot->sl_flags & NFSD4_SLOT_CACHETHIS)
+	return (resp->cstate.slot->sl_flags & NFSD4_SLOT_CACHETHIS)
 		|| nfsd4_is_solo_sequence(resp);
 }