Merge tag 'v5.2' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

21 files changed, 180 insertions, 100 deletions

diff --git a/fs/Kconfig b/fs/Kconfig
index f1046cf6ad85..bfb1c6095c7a 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -11,7 +11,6 @@ config DCACHE_WORD_ACCESS
 
 config VALIDATE_FS_PARSER
 	bool "Validate filesystem parameter description"
-	default y
 	help
 	  Enable this to perform validation of the parameter description for a
 	  filesystem when it is registered.
diff --git a/fs/afs/callback.c b/fs/afs/callback.c
index d441bef72163..915010464572 100644
--- a/fs/afs/callback.c
+++ b/fs/afs/callback.c
@@ -275,9 +275,9 @@ static void afs_break_one_callback(struct afs_server *server,
 			struct afs_super_info *as = AFS_FS_S(cbi->sb);
 			struct afs_volume *volume = as->volume;
 
-			write_lock(&volume->cb_break_lock);
+			write_lock(&volume->cb_v_break_lock);
 			volume->cb_v_break++;
-			write_unlock(&volume->cb_break_lock);
+			write_unlock(&volume->cb_v_break_lock);
 		} else {
 			data.volume = NULL;
 			data.fid = *fid;
diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index b42d9d09669c..18a50d4febcf 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -56,6 +56,16 @@ static noinline void dump_vnode(struct afs_vnode *vnode, struct afs_vnode *paren
 }
 
 /*
+ * Set the file size and block count.  Estimate the number of 512 bytes blocks
+ * used, rounded up to nearest 1K for consistency with other AFS clients.
+ */
+static void afs_set_i_size(struct afs_vnode *vnode, u64 size)
+{
+	i_size_write(&vnode->vfs_inode, size);
+	vnode->vfs_inode.i_blocks = ((size + 1023) >> 10) << 1;
+}
+
+/*
  * Initialise an inode from the vnode status.
  */
 static int afs_inode_init_from_status(struct afs_vnode *vnode, struct key *key,
@@ -124,12 +134,7 @@ static int afs_inode_init_from_status(struct afs_vnode *vnode, struct key *key,
 		return afs_protocol_error(NULL, -EBADMSG, afs_eproto_file_type);
 	}
 
-	/*
-	 * Estimate 512 bytes  blocks used, rounded up to nearest 1K
-	 * for consistency with other AFS clients.
-	 */
-	inode->i_blocks		= ((i_size_read(inode) + 1023) >> 10) << 1;
-	i_size_write(&vnode->vfs_inode, status->size);
+	afs_set_i_size(vnode, status->size);
 
 	vnode->invalid_before	= status->data_version;
 	inode_set_iversion_raw(&vnode->vfs_inode, status->data_version);
@@ -207,11 +212,13 @@ static void afs_apply_status(struct afs_fs_cursor *fc,
 
 	if (expected_version &&
 	    *expected_version != status->data_version) {
-		kdebug("vnode modified %llx on {%llx:%llu} [exp %llx] %s",
-		       (unsigned long long) status->data_version,
-		       vnode->fid.vid, vnode->fid.vnode,
-		       (unsigned long long) *expected_version,
-		       fc->type ? fc->type->name : "???");
+		if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags))
+			pr_warn("kAFS: vnode modified {%llx:%llu} %llx->%llx %s\n",
+				vnode->fid.vid, vnode->fid.vnode,
+				(unsigned long long)*expected_version,
+				(unsigned long long)status->data_version,
+				fc->type ? fc->type->name : "???");
+
 		vnode->invalid_before = status->data_version;
 		if (vnode->status.type == AFS_FTYPE_DIR) {
 			if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
@@ -230,7 +237,7 @@ static void afs_apply_status(struct afs_fs_cursor *fc,
 
 	if (data_changed) {
 		inode_set_iversion_raw(&vnode->vfs_inode, status->data_version);
-		i_size_write(&vnode->vfs_inode, status->size);
+		afs_set_i_size(vnode, status->size);
 	}
 }
 
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 8a67bf741880..7ee63526c6a2 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -109,10 +109,8 @@ struct afs_call {
 	struct rxrpc_call	*rxcall;	/* RxRPC call handle */
 	struct key		*key;		/* security for this call */
 	struct afs_net		*net;		/* The network namespace */
-	union {
-		struct afs_server	*server;
-		struct afs_vlserver	*vlserver;
-	};
+	struct afs_server	*server;	/* The fileserver record if fs op (pins ref) */
+	struct afs_vlserver	*vlserver;	/* The vlserver record if vl op */
 	struct afs_cb_interest	*cbi;		/* Callback interest for server used */
 	struct afs_vnode	*lvnode;	/* vnode being locked */
 	void			*request;	/* request data (first part) */
@@ -616,7 +614,7 @@ struct afs_volume {
 	unsigned int		servers_seq;	/* Incremented each time ->servers changes */
 
 	unsigned		cb_v_break;	/* Break-everything counter. */
-	rwlock_t		cb_break_lock;
+	rwlock_t		cb_v_break_lock;
 
 	afs_voltype_t		type;		/* type of volume */
 	short			error;
diff --git a/fs/afs/volume.c b/fs/afs/volume.c
index 08fdb3951c49..1a414300b654 100644
--- a/fs/afs/volume.c
+++ b/fs/afs/volume.c
@@ -43,6 +43,7 @@ static struct afs_volume *afs_alloc_volume(struct afs_fs_context *params,
 	atomic_set(&volume->usage, 1);
 	INIT_LIST_HEAD(&volume->proc_link);
 	rwlock_init(&volume->servers_lock);
+	rwlock_init(&volume->cb_v_break_lock);
 	memcpy(volume->name, vldb->name, vldb->name_len + 1);
 
 	slist = afs_alloc_server_list(params->cell, params->key, vldb, type_mask);
diff --git a/fs/aio.c b/fs/aio.c
index 3490d1fa0e16..c1e581dd32f5 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -2095,6 +2095,7 @@ SYSCALL_DEFINE6(io_pgetevents,
 	struct __aio_sigset	ksig = { NULL, };
 	sigset_t		ksigmask, sigsaved;
 	struct timespec64	ts;
+	bool interrupted;
 	int ret;
 
 	if (timeout && unlikely(get_timespec64(&ts, timeout)))
@@ -2108,8 +2109,10 @@ SYSCALL_DEFINE6(io_pgetevents,
 		return ret;
 
 	ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL);
-	restore_user_sigmask(ksig.sigmask, &sigsaved);
-	if (signal_pending(current) && !ret)
+
+	interrupted = signal_pending(current);
+	restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+	if (interrupted && !ret)
 		ret = -ERESTARTNOHAND;
 
 	return ret;
@@ -2128,6 +2131,7 @@ SYSCALL_DEFINE6(io_pgetevents_time32,
 	struct __aio_sigset	ksig = { NULL, };
 	sigset_t		ksigmask, sigsaved;
 	struct timespec64	ts;
+	bool interrupted;
 	int ret;
 
 	if (timeout && unlikely(get_old_timespec32(&ts, timeout)))
@@ -2142,8 +2146,10 @@ SYSCALL_DEFINE6(io_pgetevents_time32,
 		return ret;
 
 	ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL);
-	restore_user_sigmask(ksig.sigmask, &sigsaved);
-	if (signal_pending(current) && !ret)
+
+	interrupted = signal_pending(current);
+	restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+	if (interrupted && !ret)
 		ret = -ERESTARTNOHAND;
 
 	return ret;
@@ -2193,6 +2199,7 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents,
 	struct __compat_aio_sigset ksig = { NULL, };
 	sigset_t ksigmask, sigsaved;
 	struct timespec64 t;
+	bool interrupted;
 	int ret;
 
 	if (timeout && get_old_timespec32(&t, timeout))
@@ -2206,8 +2213,10 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents,
 		return ret;
 
 	ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL);
-	restore_user_sigmask(ksig.sigmask, &sigsaved);
-	if (signal_pending(current) && !ret)
+
+	interrupted = signal_pending(current);
+	restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+	if (interrupted && !ret)
 		ret = -ERESTARTNOHAND;
 
 	return ret;
@@ -2226,6 +2235,7 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64,
 	struct __compat_aio_sigset ksig = { NULL, };
 	sigset_t ksigmask, sigsaved;
 	struct timespec64 t;
+	bool interrupted;
 	int ret;
 
 	if (timeout && get_timespec64(&t, timeout))
@@ -2239,8 +2249,10 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64,
 		return ret;
 
 	ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL);
-	restore_user_sigmask(ksig.sigmask, &sigsaved);
-	if (signal_pending(current) && !ret)
+
+	interrupted = signal_pending(current);
+	restore_user_sigmask(ksig.sigmask, &sigsaved, interrupted);
+	if (interrupted && !ret)
 		ret = -ERESTARTNOHAND;
 
 	return ret;
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 82a48e830018..e4b59e76afb0 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -856,9 +856,14 @@ err:
 
 static int load_flat_shared_library(int id, struct lib_info *libs)
 {
+	/*
+	 * This is a fake bprm struct; only the members "buf", "file" and
+	 * "filename" are actually used.
+	 */
 	struct linux_binprm bprm;
 	int res;
 	char buf[16];
+	loff_t pos = 0;
 
 	memset(&bprm, 0, sizeof(bprm));
 
@@ -872,25 +877,11 @@ static int load_flat_shared_library(int id, struct lib_info *libs)
 	if (IS_ERR(bprm.file))
 		return res;
 
-	bprm.cred = prepare_exec_creds();
-	res = -ENOMEM;
-	if (!bprm.cred)
-		goto out;
-
-	/* We don't really care about recalculating credentials at this point
-	 * as we're past the point of no return and are dealing with shared
-	 * libraries.
-	 */
-	bprm.called_set_creds = 1;
+	res = kernel_read(bprm.file, bprm.buf, BINPRM_BUF_SIZE, &pos);
 
-	res = prepare_binprm(&bprm);
-
-	if (!res)
+	if (res >= 0)
 		res = load_flat_file(&bprm, libs, id, NULL);
 
-	abort_creds(bprm.cred);
-
-out:
 	allow_write_access(bprm.file);
 	fput(bprm.file);
 
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 6af2d0d4a87a..c8a9b89b922d 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2121,9 +2121,10 @@ retry:
 		if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
 			dout("build_path path+%d: %p SNAPDIR\n",
 			     pos, temp);
-		} else if (stop_on_nosnap && inode &&
+		} else if (stop_on_nosnap && inode && dentry != temp &&
 			   ceph_snap(inode) == CEPH_NOSNAP) {
 			spin_unlock(&temp->d_lock);
+			pos++; /* get rid of any prepended '/' */
 			break;
 		} else {
 			pos -= temp->d_name.len;
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 3fdc6a41b304..9fd56b0acd7e 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -2372,6 +2372,41 @@ smb2_get_dfs_refer(const unsigned int xid, struct cifs_ses *ses,
 	kfree(dfs_rsp);
 	return rc;
 }
+
+static int
+parse_reparse_symlink(struct reparse_symlink_data_buffer *symlink_buf,
+		      u32 plen, char **target_path,
+		      struct cifs_sb_info *cifs_sb)
+{
+	unsigned int sub_len;
+	unsigned int sub_offset;
+
+	/* We only handle Symbolic Link : MS-FSCC 2.1.2.4 */
+	if (le32_to_cpu(symlink_buf->ReparseTag) != IO_REPARSE_TAG_SYMLINK) {
+		cifs_dbg(VFS, "srv returned invalid symlink buffer\n");
+		return -EIO;
+	}
+
+	sub_offset = le16_to_cpu(symlink_buf->SubstituteNameOffset);
+	sub_len = le16_to_cpu(symlink_buf->SubstituteNameLength);
+	if (sub_offset + 20 > plen ||
+	    sub_offset + sub_len + 20 > plen) {
+		cifs_dbg(VFS, "srv returned malformed symlink buffer\n");
+		return -EIO;
+	}
+
+	*target_path = cifs_strndup_from_utf16(
+				symlink_buf->PathBuffer + sub_offset,
+				sub_len, true, cifs_sb->local_nls);
+	if (!(*target_path))
+		return -ENOMEM;
+
+	convert_delimiter(*target_path, '/');
+	cifs_dbg(FYI, "%s: target path: %s\n", __func__, *target_path);
+
+	return 0;
+}
+
 #define SMB2_SYMLINK_STRUCT_SIZE \
 	(sizeof(struct smb2_err_rsp) - 1 + sizeof(struct smb2_symlink_err_rsp))
 
@@ -2401,11 +2436,13 @@ smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
 	struct kvec close_iov[1];
 	struct smb2_create_rsp *create_rsp;
 	struct smb2_ioctl_rsp *ioctl_rsp;
-	char *ioctl_buf;
+	struct reparse_data_buffer *reparse_buf;
 	u32 plen;
 
 	cifs_dbg(FYI, "%s: path: %s\n", __func__, full_path);
 
+	*target_path = NULL;
+
 	if (smb3_encryption_required(tcon))
 		flags |= CIFS_TRANSFORM_REQ;
 
@@ -2483,17 +2520,36 @@ smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
 	if ((rc == 0) && (is_reparse_point)) {
 		/* See MS-FSCC 2.3.23 */
 
-		ioctl_buf = (char *)ioctl_rsp + le32_to_cpu(ioctl_rsp->OutputOffset);
+		reparse_buf = (struct reparse_data_buffer *)
+			((char *)ioctl_rsp +
+			 le32_to_cpu(ioctl_rsp->OutputOffset));
 		plen = le32_to_cpu(ioctl_rsp->OutputCount);
 
 		if (plen + le32_to_cpu(ioctl_rsp->OutputOffset) >
 		    rsp_iov[1].iov_len) {
-			cifs_dbg(VFS, "srv returned invalid ioctl length: %d\n", plen);
+			cifs_dbg(VFS, "srv returned invalid ioctl len: %d\n",
+				 plen);
+			rc = -EIO;
+			goto querty_exit;
+		}
+
+		if (plen < 8) {
+			cifs_dbg(VFS, "reparse buffer is too small. Must be "
+				 "at least 8 bytes but was %d\n", plen);
+			rc = -EIO;
+			goto querty_exit;
+		}
+
+		if (plen < le16_to_cpu(reparse_buf->ReparseDataLength) + 8) {
+			cifs_dbg(VFS, "srv returned invalid reparse buf "
+				 "length: %d\n", plen);
 			rc = -EIO;
 			goto querty_exit;
 		}
 
-		/* Do stuff with ioctl_buf/plen */
+		rc = parse_reparse_symlink(
+			(struct reparse_symlink_data_buffer *)reparse_buf,
+			plen, target_path, cifs_sb);
 		goto querty_exit;
 	}
 
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index c7d5813bebd8..858353d20c39 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -914,7 +914,19 @@ struct reparse_mount_point_data_buffer {
 	__u8	PathBuffer[0]; /* Variable Length */
 } __packed;
 
-/* See MS-FSCC 2.1.2.4 and cifspdu.h for struct reparse_symlink_data */
+#define SYMLINK_FLAG_RELATIVE 0x00000001
+
+struct reparse_symlink_data_buffer {
+	__le32	ReparseTag;
+	__le16	ReparseDataLength;
+	__u16	Reserved;
+	__le16	SubstituteNameOffset;
+	__le16	SubstituteNameLength;
+	__le16	PrintNameOffset;
+	__le16	PrintNameLength;
+	__le32	Flags;
+	__u8	PathBuffer[0]; /* Variable Length */
+} __packed;
 
 /* See MS-FSCC 2.1.2.6 and cifspdu.h for struct reparse_posix_data */
 
diff --git a/fs/dax.c b/fs/dax.c
index 2e48c7ebb973..d2c90bf1969a 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -720,12 +720,11 @@ static void *dax_insert_entry(struct xa_state *xas,
 
 	xas_reset(xas);
 	xas_lock_irq(xas);
-	if (dax_entry_size(entry) != dax_entry_size(new_entry)) {
+	if (dax_is_zero_entry(entry) || dax_is_empty_entry(entry)) {
+		void *old;
+
 		dax_disassociate_entry(entry, mapping, false);
 		dax_associate_entry(new_entry, mapping, vmf->vma, vmf->address);
-	}
-
-	if (dax_is_zero_entry(entry) || dax_is_empty_entry(entry)) {
 		/*
 		 * Only swap our new entry into the page cache if the current
 		 * entry is a zero page or an empty entry.  If a normal PTE or
@@ -734,7 +733,7 @@ static void *dax_insert_entry(struct xa_state *xas,
 		 * existing entry is a PMD, we will just leave the PMD in the
 		 * tree and dirty it if necessary.
 		 */
-		void *old = dax_lock_entry(xas, new_entry);
+		old = dax_lock_entry(xas, new_entry);
 		WARN_ON_ONCE(old != xa_mk_value(xa_to_value(entry) |
 					DAX_LOCKED));
 		entry = new_entry;
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index c6f513100cc9..4c74c768ae43 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -2325,7 +2325,7 @@ SYSCALL_DEFINE6(epoll_pwait, int, epfd, struct epoll_event __user *, events,
 
 	error = do_epoll_wait(epfd, events, maxevents, timeout);
 
-	restore_user_sigmask(sigmask, &sigsaved);
+	restore_user_sigmask(sigmask, &sigsaved, error == -EINTR);
 
 	return error;
 }
@@ -2350,7 +2350,7 @@ COMPAT_SYSCALL_DEFINE6(epoll_pwait, int, epfd,
 
 	err = do_epoll_wait(epfd, events, maxevents, timeout);
 
-	restore_user_sigmask(sigmask, &sigsaved);
+	restore_user_sigmask(sigmask, &sigsaved, err == -EINTR);
 
 	return err;
 }
diff --git a/fs/inode.c b/fs/inode.c
index df6542ec3b88..2bf21e2c90fc 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -362,7 +362,7 @@ EXPORT_SYMBOL(inc_nlink);
 
 static void __address_space_init_once(struct address_space *mapping)
 {
-	xa_init_flags(&mapping->i_pages, XA_FLAGS_LOCK_IRQ);
+	xa_init_flags(&mapping->i_pages, XA_FLAGS_LOCK_IRQ | XA_FLAGS_ACCOUNT);
 	init_rwsem(&mapping->i_mmap_rwsem);
 	INIT_LIST_HEAD(&mapping->private_list);
 	spin_lock_init(&mapping->private_lock);
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 86a2bd721900..4ef62a45045d 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -579,6 +579,7 @@ static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx,
 		state->cur_req++;
 	}
 
+	req->file = NULL;
 	req->ctx = ctx;
 	req->flags = 0;
 	/* one is dropped after submission, the other at completion */
@@ -1801,10 +1802,8 @@ static int io_req_set_file(struct io_ring_ctx *ctx, const struct sqe_submit *s,
 		req->sequence = ctx->cached_sq_head - 1;
 	}
 
-	if (!io_op_needs_file(s->sqe)) {
-		req->file = NULL;
+	if (!io_op_needs_file(s->sqe))
 		return 0;
-	}
 
 	if (flags & IOSQE_FIXED_FILE) {
 		if (unlikely(!ctx->user_files ||
@@ -2201,11 +2200,12 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
 	}
 
 	ret = wait_event_interruptible(ctx->wait, io_cqring_events(ring) >= min_events);
-	if (ret == -ERESTARTSYS)
-		ret = -EINTR;
 
 	if (sig)
-		restore_user_sigmask(sig, &sigsaved);
+		restore_user_sigmask(sig, &sigsaved, ret == -ERESTARTSYS);
+
+	if (ret == -ERESTARTSYS)
+		ret = -EINTR;
 
 	return READ_ONCE(ring->r.head) == READ_ONCE(ring->r.tail) ? ret : 0;
 }
diff --git a/fs/namespace.c b/fs/namespace.c
index 7660c2749c96..6fbc9126367a 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2596,11 +2596,12 @@ static int do_move_mount(struct path *old_path, struct path *new_path)
 	if (!check_mnt(p))
 		goto out;
 
-	/* The thing moved should be either ours or completely unattached. */
-	if (attached && !check_mnt(old))
+	/* The thing moved must be mounted... */
+	if (!is_mounted(&old->mnt))
 		goto out;
 
-	if (!attached && !(ns && is_anon_ns(ns)))
+	/* ... and either ours or the root of anon namespace */
+	if (!(attached ? check_mnt(old) : is_anon_ns(ns)))
 		goto out;
 
 	if (old->mnt.mnt_flags & MNT_LOCKED)
diff --git a/fs/nfs/flexfilelayout/flexfilelayoutdev.c b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
index a809989807d6..19f856f45689 100644
--- a/fs/nfs/flexfilelayout/flexfilelayoutdev.c
+++ b/fs/nfs/flexfilelayout/flexfilelayoutdev.c
@@ -18,7 +18,7 @@
 
 #define NFSDBG_FACILITY		NFSDBG_PNFS_LD
 
-static unsigned int dataserver_timeo = NFS_DEF_TCP_RETRANS;
+static unsigned int dataserver_timeo = NFS_DEF_TCP_TIMEO;
 static unsigned int dataserver_retrans;
 
 static bool ff_layout_has_available_ds(struct pnfs_layout_segment *lseg);
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 618e66078ee5..1a0cdeb3b875 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1563,7 +1563,7 @@ static u32 nfsd4_get_drc_mem(struct nfsd4_channel_attrs *ca)
 	 * Never use more than a third of the remaining memory,
 	 * unless it's the only way to give this client a slot:
 	 */
-	avail = clamp_t(int, avail, slotsize, total_avail/3);
+	avail = clamp_t(unsigned long, avail, slotsize, total_avail/3);
 	num = min_t(int, num, avail / slotsize);
 	nfsd_drc_mem_used += num * slotsize;
 	spin_unlock(&nfsd_drc_lock);
diff --git a/fs/proc/array.c b/fs/proc/array.c
index 2edbb657f859..55180501b915 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -462,7 +462,7 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
 		 * a program is not able to use ptrace(2) in that case. It is
 		 * safe because the task has stopped executing permanently.
 		 */
-		if (permitted && (task->flags & PF_DUMPCORE)) {
+		if (permitted && (task->flags & (PF_EXITING|PF_DUMPCORE))) {
 			if (try_get_task_stack(task)) {
 				eip = KSTK_EIP(task);
 				esp = KSTK_ESP(task);
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 9c8ca6cd3ce4..255f6754c70d 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -3077,8 +3077,7 @@ static const struct file_operations proc_tgid_base_operations = {
 
 struct pid *tgid_pidfd_to_pid(const struct file *file)
 {
-	if (!d_is_dir(file->f_path.dentry) ||
-	    (file->f_op != &proc_tgid_base_operations))
+	if (file->f_op != &proc_tgid_base_operations)
 		return ERR_PTR(-EBADF);
 
 	return proc_pid(file_inode(file));
diff --git a/fs/select.c b/fs/select.c
index 6cbc9ff56ba0..a4d8f6e8b63c 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -758,10 +758,9 @@ static long do_pselect(int n, fd_set __user *inp, fd_set __user *outp,
 		return ret;
 
 	ret = core_sys_select(n, inp, outp, exp, to);
+	restore_user_sigmask(sigmask, &sigsaved, ret == -ERESTARTNOHAND);
 	ret = poll_select_copy_remaining(&end_time, tsp, type, ret);
 
-	restore_user_sigmask(sigmask, &sigsaved);
-
 	return ret;
 }
 
@@ -1106,8 +1105,7 @@ SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds,
 
 	ret = do_sys_poll(ufds, nfds, to);
 
-	restore_user_sigmask(sigmask, &sigsaved);
-
+	restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
 	/* We can restart this syscall, usually */
 	if (ret == -EINTR)
 		ret = -ERESTARTNOHAND;
@@ -1142,8 +1140,7 @@ SYSCALL_DEFINE5(ppoll_time32, struct pollfd __user *, ufds, unsigned int, nfds,
 
 	ret = do_sys_poll(ufds, nfds, to);
 
-	restore_user_sigmask(sigmask, &sigsaved);
-
+	restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
 	/* We can restart this syscall, usually */
 	if (ret == -EINTR)
 		ret = -ERESTARTNOHAND;
@@ -1350,10 +1347,9 @@ static long do_compat_pselect(int n, compat_ulong_t __user *inp,
 		return ret;
 
 	ret = compat_core_sys_select(n, inp, outp, exp, to);
+	restore_user_sigmask(sigmask, &sigsaved, ret == -ERESTARTNOHAND);
 	ret = poll_select_copy_remaining(&end_time, tsp, type, ret);
 
-	restore_user_sigmask(sigmask, &sigsaved);
-
 	return ret;
 }
 
@@ -1425,8 +1421,7 @@ COMPAT_SYSCALL_DEFINE5(ppoll_time32, struct pollfd __user *, ufds,
 
 	ret = do_sys_poll(ufds, nfds, to);
 
-	restore_user_sigmask(sigmask, &sigsaved);
-
+	restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
 	/* We can restart this syscall, usually */
 	if (ret == -EINTR)
 		ret = -ERESTARTNOHAND;
@@ -1461,8 +1456,7 @@ COMPAT_SYSCALL_DEFINE5(ppoll_time64, struct pollfd __user *, ufds,
 
 	ret = do_sys_poll(ufds, nfds, to);
 
-	restore_user_sigmask(sigmask, &sigsaved);
-
+	restore_user_sigmask(sigmask, &sigsaved, ret == -EINTR);
 	/* We can restart this syscall, usually */
 	if (ret == -EINTR)
 		ret = -ERESTARTNOHAND;
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index ae0b8b5f69e6..ccbdbd62f0d8 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -40,6 +40,16 @@ enum userfaultfd_state {
 /*
  * Start with fault_pending_wqh and fault_wqh so they're more likely
  * to be in the same cacheline.
+ *
+ * Locking order:
+ *	fd_wqh.lock
+ *		fault_pending_wqh.lock
+ *			fault_wqh.lock
+ *		event_wqh.lock
+ *
+ * To avoid deadlocks, IRQs must be disabled when taking any of the above locks,
+ * since fd_wqh.lock is taken by aio_poll() while it's holding a lock that's
+ * also taken in IRQ context.
  */
 struct userfaultfd_ctx {
 	/* waitqueue head for the pending (i.e. not read) userfaults */
@@ -458,7 +468,7 @@ vm_fault_t handle_userfault(struct vm_fault *vmf, unsigned long reason)
 	blocking_state = return_to_userland ? TASK_INTERRUPTIBLE :
 			 TASK_KILLABLE;
 
-	spin_lock(&ctx->fault_pending_wqh.lock);
+	spin_lock_irq(&ctx->fault_pending_wqh.lock);
 	/*
 	 * After the __add_wait_queue the uwq is visible to userland
 	 * through poll/read().
@@ -470,7 +480,7 @@ vm_fault_t handle_userfault(struct vm_fault *vmf, unsigned long reason)
 	 * __add_wait_queue.
 	 */
 	set_current_state(blocking_state);
-	spin_unlock(&ctx->fault_pending_wqh.lock);
+	spin_unlock_irq(&ctx->fault_pending_wqh.lock);
 
 	if (!is_vm_hugetlb_page(vmf->vma))
 		must_wait = userfaultfd_must_wait(ctx, vmf->address, vmf->flags,
@@ -552,13 +562,13 @@ vm_fault_t handle_userfault(struct vm_fault *vmf, unsigned long reason)
 	 * kernel stack can be released after the list_del_init.
 	 */
 	if (!list_empty_careful(&uwq.wq.entry)) {
-		spin_lock(&ctx->fault_pending_wqh.lock);
+		spin_lock_irq(&ctx->fault_pending_wqh.lock);
 		/*
 		 * No need of list_del_init(), the uwq on the stack
 		 * will be freed shortly anyway.
 		 */
 		list_del(&uwq.wq.entry);
-		spin_unlock(&ctx->fault_pending_wqh.lock);
+		spin_unlock_irq(&ctx->fault_pending_wqh.lock);
 	}
 
 	/*
@@ -583,7 +593,7 @@ static void userfaultfd_event_wait_completion(struct userfaultfd_ctx *ctx,
 	init_waitqueue_entry(&ewq->wq, current);
 	release_new_ctx = NULL;
 
-	spin_lock(&ctx->event_wqh.lock);
+	spin_lock_irq(&ctx->event_wqh.lock);
 	/*
 	 * After the __add_wait_queue the uwq is visible to userland
 	 * through poll/read().
@@ -613,15 +623,15 @@ static void userfaultfd_event_wait_completion(struct userfaultfd_ctx *ctx,
 			break;
 		}
 
-		spin_unlock(&ctx->event_wqh.lock);
+		spin_unlock_irq(&ctx->event_wqh.lock);
 
 		wake_up_poll(&ctx->fd_wqh, EPOLLIN);
 		schedule();
 
-		spin_lock(&ctx->event_wqh.lock);
+		spin_lock_irq(&ctx->event_wqh.lock);
 	}
 	__set_current_state(TASK_RUNNING);
-	spin_unlock(&ctx->event_wqh.lock);
+	spin_unlock_irq(&ctx->event_wqh.lock);
 
 	if (release_new_ctx) {
 		struct vm_area_struct *vma;
@@ -918,10 +928,10 @@ wakeup:
 	 * the last page faults that may have been already waiting on
 	 * the fault_*wqh.
 	 */
-	spin_lock(&ctx->fault_pending_wqh.lock);
+	spin_lock_irq(&ctx->fault_pending_wqh.lock);
 	__wake_up_locked_key(&ctx->fault_pending_wqh, TASK_NORMAL, &range);
 	__wake_up(&ctx->fault_wqh, TASK_NORMAL, 1, &range);
-	spin_unlock(&ctx->fault_pending_wqh.lock);
+	spin_unlock_irq(&ctx->fault_pending_wqh.lock);
 
 	/* Flush pending events that may still wait on event_wqh */
 	wake_up_all(&ctx->event_wqh);
@@ -1134,7 +1144,7 @@ static ssize_t userfaultfd_ctx_read(struct userfaultfd_ctx *ctx, int no_wait,
 
 	if (!ret && msg->event == UFFD_EVENT_FORK) {
 		ret = resolve_userfault_fork(ctx, fork_nctx, msg);
-		spin_lock(&ctx->event_wqh.lock);
+		spin_lock_irq(&ctx->event_wqh.lock);
 		if (!list_empty(&fork_event)) {
 			/*
 			 * The fork thread didn't abort, so we can
@@ -1180,7 +1190,7 @@ static ssize_t userfaultfd_ctx_read(struct userfaultfd_ctx *ctx, int no_wait,
 			if (ret)
 				userfaultfd_ctx_put(fork_nctx);
 		}
-		spin_unlock(&ctx->event_wqh.lock);
+		spin_unlock_irq(&ctx->event_wqh.lock);
 	}
 
 	return ret;
@@ -1219,14 +1229,14 @@ static ssize_t userfaultfd_read(struct file *file, char __user *buf,
 static void __wake_userfault(struct userfaultfd_ctx *ctx,
 			     struct userfaultfd_wake_range *range)
 {
-	spin_lock(&ctx->fault_pending_wqh.lock);
+	spin_lock_irq(&ctx->fault_pending_wqh.lock);
 	/* wake all in the range and autoremove */
 	if (waitqueue_active(&ctx->fault_pending_wqh))
 		__wake_up_locked_key(&ctx->fault_pending_wqh, TASK_NORMAL,
 				     range);
 	if (waitqueue_active(&ctx->fault_wqh))
 		__wake_up(&ctx->fault_wqh, TASK_NORMAL, 1, range);
-	spin_unlock(&ctx->fault_pending_wqh.lock);
+	spin_unlock_irq(&ctx->fault_pending_wqh.lock);
 }
 
 static __always_inline void wake_userfault(struct userfaultfd_ctx *ctx,
@@ -1881,7 +1891,7 @@ static void userfaultfd_show_fdinfo(struct seq_file *m, struct file *f)
 	wait_queue_entry_t *wq;
 	unsigned long pending = 0, total = 0;
 
-	spin_lock(&ctx->fault_pending_wqh.lock);
+	spin_lock_irq(&ctx->fault_pending_wqh.lock);
 	list_for_each_entry(wq, &ctx->fault_pending_wqh.head, entry) {
 		pending++;
 		total++;
@@ -1889,7 +1899,7 @@ static void userfaultfd_show_fdinfo(struct seq_file *m, struct file *f)
 	list_for_each_entry(wq, &ctx->fault_wqh.head, entry) {
 		total++;
 	}
-	spin_unlock(&ctx->fault_pending_wqh.lock);
+	spin_unlock_irq(&ctx->fault_pending_wqh.lock);
 
 	/*
 	 * If more protocols will be added, there will be all shown