This is a note to let you know that I've just added the patch titled
ksmbd: use wait_event instead of schedule_timeout()
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ksmbd-use-wait_event-instead-of-schedule_timeout.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From linkinjeon@xxxxxxxxx Mon Dec 18 16:37:48 2023
From: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Date: Tue, 19 Dec 2023 00:33:05 +0900
Subject: ksmbd: use wait_event instead of schedule_timeout()
To: gregkh@xxxxxxxxxxxxxxxxxxx, stable@xxxxxxxxxxxxxxx
Cc: smfrench@xxxxxxxxx, Namjae Jeon <linkinjeon@xxxxxxxxxx>, Hyunchul Lee <hyc.lee@xxxxxxxxx>, Steve French <stfrench@xxxxxxxxxxxxx>
Message-ID: <20231218153454.8090-46-linkinjeon@xxxxxxxxxx>
From: Namjae Jeon <linkinjeon@xxxxxxxxxx>
[ Upstream commit a14c573870a664386adc10526a6c2648ea56dae1 ]
ksmbd threads eating masses of cputime when connection is disconnected.
If connection is disconnected, ksmbd thread waits for pending requests
to be processed using schedule_timeout. schedule_timeout() incorrectly
is used, and it is more efficient to use wait_event/wake_up than to check
r_count every time with timeout.
Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Reviewed-by: Hyunchul Lee <hyc.lee@xxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ksmbd/connection.c | 6 +++---
fs/ksmbd/connection.h | 1 +
fs/ksmbd/oplock.c | 35 ++++++++++++++++++++++-------------
fs/ksmbd/server.c | 8 +++++++-
4 files changed, 33 insertions(+), 17 deletions(-)
--- a/fs/ksmbd/connection.c
+++ b/fs/ksmbd/connection.c
@@ -66,6 +66,7 @@ struct ksmbd_conn *ksmbd_conn_alloc(void
conn->outstanding_credits = 0;
init_waitqueue_head(&conn->req_running_q);
+ init_waitqueue_head(&conn->r_count_q);
INIT_LIST_HEAD(&conn->conns_list);
INIT_LIST_HEAD(&conn->requests);
INIT_LIST_HEAD(&conn->async_requests);
@@ -165,7 +166,6 @@ int ksmbd_conn_write(struct ksmbd_work *
struct kvec iov[3];
int iov_idx = 0;
- ksmbd_conn_try_dequeue_request(work);
if (!work->response_buf) {
pr_err("NULL response header\n");
return -EINVAL;
@@ -358,8 +358,8 @@ int ksmbd_conn_handler_loop(void *p)
out:
/* Wait till all reference dropped to the Server object*/
- while (atomic_read(&conn->r_count) > 0)
- schedule_timeout(HZ);
+ wait_event(conn->r_count_q, atomic_read(&conn->r_count) == 0);
+
unload_nls(conn->local_nls);
if (default_conn_ops.terminate_fn)
--- a/fs/ksmbd/connection.h
+++ b/fs/ksmbd/connection.h
@@ -58,6 +58,7 @@ struct ksmbd_conn {
unsigned int outstanding_credits;
spinlock_t credits_lock;
wait_queue_head_t req_running_q;
+ wait_queue_head_t r_count_q;
/* Lock to protect requests list*/
spinlock_t request_lock;
struct list_head requests;
--- a/fs/ksmbd/oplock.c
+++ b/fs/ksmbd/oplock.c
@@ -616,18 +616,13 @@ static void __smb2_oplock_break_noti(str
struct ksmbd_file *fp;
fp = ksmbd_lookup_durable_fd(br_info->fid);
- if (!fp) {
- atomic_dec(&conn->r_count);
- ksmbd_free_work_struct(work);
- return;
- }
+ if (!fp)
+ goto out;
if (allocate_oplock_break_buf(work)) {
pr_err("smb2_allocate_rsp_buf failed! ");
- atomic_dec(&conn->r_count);
ksmbd_fd_put(work, fp);
- ksmbd_free_work_struct(work);
- return;
+ goto out;
}
rsp_hdr = smb2_get_msg(work->response_buf);
@@ -668,8 +663,16 @@ static void __smb2_oplock_break_noti(str
ksmbd_fd_put(work, fp);
ksmbd_conn_write(work);
+
+out:
ksmbd_free_work_struct(work);
- atomic_dec(&conn->r_count);
+ /*
+ * Checking waitqueue to dropping pending requests on
+ * disconnection. waitqueue_active is safe because it
+ * uses atomic operation for condition.
+ */
+ if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q))
+ wake_up(&conn->r_count_q);
}
/**
@@ -732,9 +735,7 @@ static void __smb2_lease_break_noti(stru
if (allocate_oplock_break_buf(work)) {
ksmbd_debug(OPLOCK, "smb2_allocate_rsp_buf failed! ");
- ksmbd_free_work_struct(work);
- atomic_dec(&conn->r_count);
- return;
+ goto out;
}
rsp_hdr = smb2_get_msg(work->response_buf);
@@ -772,8 +773,16 @@ static void __smb2_lease_break_noti(stru
inc_rfc1001_len(work->response_buf, 44);
ksmbd_conn_write(work);
+
+out:
ksmbd_free_work_struct(work);
- atomic_dec(&conn->r_count);
+ /*
+ * Checking waitqueue to dropping pending requests on
+ * disconnection. waitqueue_active is safe because it
+ * uses atomic operation for condition.
+ */
+ if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q))
+ wake_up(&conn->r_count_q);
}
/**
--- a/fs/ksmbd/server.c
+++ b/fs/ksmbd/server.c
@@ -266,7 +266,13 @@ static void handle_ksmbd_work(struct wor
ksmbd_conn_try_dequeue_request(work);
ksmbd_free_work_struct(work);
- atomic_dec(&conn->r_count);
+ /*
+ * Checking waitqueue to dropping pending requests on
+ * disconnection. waitqueue_active is safe because it
+ * uses atomic operation for condition.
+ */
+ if (!atomic_dec_return(&conn->r_count) && waitqueue_active(&conn->r_count_q))
+ wake_up(&conn->r_count_q);
}
/**
Patches currently in stable-queue which might be from linkinjeon@xxxxxxxxx are
queue-5.15/ksmbd-fix-uaf-issue-from-opinfo-conn.patch
queue-5.15/ksmbd-fix-race-condition-from-parallel-smb2-lock-requests.patch
queue-5.15/ksmbd-validate-session-id-and-tree-id-in-compound-request.patch
queue-5.15/ksmbd-reorganize-ksmbd_iov_pin_rsp.patch
queue-5.15/ksmbd-convert-to-use-sysfs_emit-sysfs_emit_at-apis.patch
queue-5.15/ksmbd-validate-length-in-smb2_write.patch
queue-5.15/ksmbd-add-support-for-key-exchange.patch
queue-5.15/ksmbd-request-update-to-stale-share-config.patch
queue-5.15/ksmbd-remove-generic_fillattr-use-in-smb2_open.patch
queue-5.15/ksmbd-fix-uninitialized-pointer-read-in-smb2_create_link.patch
queue-5.15/ksmbd-set-smb2_session_flag_encrypt_data-when-enforcing-data-encryption-for-this-share.patch
queue-5.15/ksmbd-constify-struct-path.patch
queue-5.15/ksmbd-casefold-utf-8-share-names-and-fix-ascii-lowercase-conversion.patch
queue-5.15/ksmbd-validate-smb-request-protocol-id.patch
queue-5.15/ksmbd-avoid-out-of-bounds-access-in-decode_preauth_ctxt.patch
queue-5.15/ksmbd-release-interim-response-after-sending-status-pending-response.patch
queue-5.15/ksmbd-fix-racy-issue-under-cocurrent-smb2-tree-disconnect.patch
queue-5.15/ksmbd-fix-out-of-bounds-read-in-smb2_sess_setup.patch
queue-5.15/ksmbd-decrease-the-number-of-smb3-smbdirect-server-sges.patch
queue-5.15/ksmbd-make-utf-8-file-name-comparison-work-in-__caseless_lookup.patch
queue-5.15/ksmbd-use-f_setlk-when-unlocking-a-file.patch
queue-5.15/fs-introduce-lock_rename_child-helper.patch
queue-5.15/ksmbd-use-kzalloc-instead-of-__gfp_zero.patch
queue-5.15/ksmbd-set-ntlmssp_negotiate_seal-flag-to-challenge-blob.patch
queue-5.15/ksmbd-call-ib_drain_qp-when-disconnected.patch
queue-5.15/ksmbd-fix-posix_acls-and-acls-dereferencing-possible-err_ptr.patch
queue-5.15/ksmbd-destroy-expired-sessions.patch
queue-5.15/ksmbd-fix-resource-leak-in-smb2_lock.patch
queue-5.15/ksmbd-check-iov-vector-index-in-ksmbd_conn_write.patch
queue-5.15/ksmbd-hide-socket-error-message-when-ipv6-config-is-disable.patch
queue-5.15/ksmbd-use-netif_is_bridge_port.patch
queue-5.15/ksmbd-smbd-simplify-tracking-pending-packets.patch
queue-5.15/ksmbd-implements-sess-rpc_handle_list-as-xarray.patch
queue-5.15/ksmbd-remove-duplicate-flag-set-in-smb2_write.patch
queue-5.15/ksmbd-separately-allocate-ci-per-dentry.patch
queue-5.15/ksmbd-fix-racy-issue-from-session-setup-and-logoff.patch
queue-5.15/ksmbd-fix-race-condition-between-session-lookup-and-expire.patch
queue-5.15/ksmbd-fix-wrong-smbd-max-read-write-size-check.patch
queue-5.15/ksmbd-replace-usage-of-found-with-dedicated-list-iterator-variable.patch
queue-5.15/ksmbd-add-support-for-surrogate-pair-conversion.patch
queue-5.15/ksmbd-reduce-server-smbdirect-max-send-receive-segment-sizes.patch
queue-5.15/ksmbd-fix-force-create-mode-and-force-directory-mode.patch
queue-5.15/ksmbd-remove-unneeded-mark_inode_dirty-in-set_info_sec.patch
queue-5.15/ksmbd-fix-potential-double-free-on-smb2_read_pipe-error-path.patch
queue-5.15/ksmbd-remove-unused-ksmbd_tree_conn_share-function.patch
queue-5.15/ksmbd-block-asynchronous-requests-when-making-a-delay-on-session-setup.patch
queue-5.15/ksmbd-call-putname-after-using-the-last-component.patch
queue-5.15/ksmbd-don-t-open-code-file_path.patch
queue-5.15/ksmbd-fix-passing-freed-memory-aux_payload_buf.patch
queue-5.15/ksmbd-fill-sids-in-smb_find_file_posix_info-response.patch
queue-5.15/ksmbd-don-t-open-code-pd.patch
queue-5.15/ksmbd-shorten-experimental-warning-on-loading-the-module.patch
queue-5.15/ksmbd-remove-filename-in-ksmbd_file.patch
queue-5.15/ksmbd-move-oplock-handling-after-unlock-parent-dir.patch
queue-5.15/ksmbd-fix-race-condition-between-tree-conn-lookup-and-disconnect.patch
queue-5.15/ksmbd-smbd-introduce-read-write-credits-for-rdma-read-write.patch
queue-5.15/ksmbd-fix-slab-out-of-bounds-in-init_smb2_rsp_hdr.patch
queue-5.15/ksmbd-fix-recursive-locking-in-vfs-helpers.patch
queue-5.15/ksmbd-fix-some-kernel-doc-comments.patch
queue-5.15/ksmbd-use-struct_size-helper-in-ksmbd_negotiate_smb_dialect.patch
queue-5.15/ksmbd-smbd-relax-the-count-of-sges-required.patch
queue-5.15/ksmbd-fix-wrong-error-response-status-by-using-set_smb2_rsp_status.patch
queue-5.15/ksmbd-fix-spelling-mistake-excceed-exceeded.patch
queue-5.15/ksmbd-fix-null-pointer-dereferences-in-ksmbd_update_fstate.patch
queue-5.15/ksmbd-fix-encryption-failure-issue-for-session-logoff-response.patch
queue-5.15/ksmbd-prevent-memory-leak-on-error-return.patch
queue-5.15/ksmbd-fix-racy-issue-from-using-d_parent-and-d_name.patch
queue-5.15/ksmbd-change-security-id-to-the-one-samba-used-for-posix-extension.patch
queue-5.15/ksmbd-handle-malformed-smb1-message.patch
queue-5.15/ksmbd-don-t-update-op_state-as-oplock_state_none-on-error.patch
queue-5.15/ksmbd-smbd-fix-connection-dropped-issue.patch
queue-5.15/ksmbd-fix-racy-issue-from-smb2-close-and-logoff-with-multichannel.patch
queue-5.15/ksmbd-change-the-return-value-of-ksmbd_vfs_query_maximal_access-to-void.patch
queue-5.15/ksmbd-fix-slub-overflow-in-ksmbd_decode_ntlmssp_auth_blob.patch
queue-5.15/ksmbd-replace-one-element-array-with-flexible-array-member.patch
queue-5.15/ksmbd-fix-uninitialized-pointer-read-in-ksmbd_vfs_rename.patch
queue-5.15/ksmbd-replace-one-element-arrays-with-flexible-array-members.patch
queue-5.15/ksmbd-fix-unsigned-expression-compared-with-zero.patch
queue-5.15/ksmbd-implements-sess-ksmbd_chann_list-as-xarray.patch
queue-5.15/ksmbd-set-file-permission-mode-to-match-samba-server-posix-extension-behavior.patch
queue-5.15/ksmbd-fix-wrong-interim-response-on-compound.patch
queue-5.15/ksmbd-return-invalid-parameter-error-response-if-smb2-request-is-invalid.patch
queue-5.15/ksmbd-smbd-validate-buffer-descriptor-structures.patch
queue-5.15/ksmbd-fix-missing-rdma-capable-flag-for-ipoib-device-in-ksmbd_rdma_capable_netdev.patch
queue-5.15/ksmbd-send-proper-error-response-in-smb2_tree_connect.patch
queue-5.15/ksmbd-set-negotiatecontextcount-once-instead-of-every-inc.patch
queue-5.15/ksmbd-fix-typo-syncronous-synchronous.patch
queue-5.15/ksmbd-validate-share-name-from-share-config-response.patch
queue-5.15/ksmbd-fix-possible-deadlock-in-smb2_open.patch
queue-5.15/ksmbd-fix-multiple-out-of-bounds-read-during-context-decoding.patch
queue-5.15/ksmbd-add-missing-calling-smb2_set_err_rsp-on-error.patch
queue-5.15/ksmbd-remove-unused-ksmbd_share_configs_cleanup-function.patch
queue-5.15/ksmbd-fix-out-of-bound-read-in-parse_lease_state.patch
queue-5.15/ksmbd-remove-duplicated-codes.patch
queue-5.15/ksmbd-remove-a-redundant-zeroing-of-memory.patch
queue-5.15/ksmbd-change-leasekey-data-type-to-u8-array.patch
queue-5.15/ksmbd-add-support-for-read-compound.patch
queue-5.15/ksmbd-fix-kernel-doc-comment-of-ksmbd_vfs_setxattr.patch
queue-5.15/ksmbd-remove-unused-compression-negotiate-ctx-packing.patch
queue-5.15/ksmbd-switch-to-use-kmemdup_nul-helper.patch
queue-5.15/ksmbd-fix-race-condition-from-parallel-smb2-logoff-requests.patch
queue-5.15/ksmbd-fix-out-of-bound-read-in-deassemble_neg_contexts.patch
queue-5.15/ksmbd-remove-unnecessary-generic_fillattr-in-smb2_open.patch
queue-5.15/ksmbd-avoid-duplicate-negotiate-ctx-offset-increments.patch
queue-5.15/ksmbd-remove-experimental-warning.patch
queue-5.15/ksmbd-return-a-literal-instead-of-err-in-ksmbd_vfs_kern_path_locked.patch
queue-5.15/ksmbd-smbd-change-prototypes-of-rdma-read-write-related-functions.patch
queue-5.15/ksmbd-fix-out-of-bounds-in-init_smb2_rsp_hdr.patch
queue-5.15/ksmbd-fix-possible-memory-leak-in-smb2_lock.patch
queue-5.15/ksmbd-remove-unused-field-in-ksmbd_user-struct.patch
queue-5.15/ksmbd-fix-one-kernel-doc-comment.patch
queue-5.15/ksmbd-no-need-to-wait-for-binded-connection-termination-at-logoff.patch
queue-5.15/ksmbd-fix-race-condition-with-fp.patch
queue-5.15/ksmbd-fix-wrong-signingkey-creation-when-encryption-is-aes256.patch
queue-5.15/ksmbd-update-kconfig-to-note-kerberos-support-and-fix-indentation.patch
queue-5.15/ksmbd-move-setting-smb2_flags_async_command-and-asyncid.patch
queue-5.15/smb3-fix-ksmbd-bigendian-bug-in-oplock-break-and-move-its-struct-to-smbfs_common.patch
queue-5.15/ksmbd-store-fids-as-opaque-u64-integers.patch
queue-5.15/ksmbd-delete-asynchronous-work-from-list.patch
queue-5.15/ksmbd-use-kvzalloc-instead-of-kvmalloc.patch
queue-5.15/ksmbd-smbd-change-the-return-value-of-get_sg_list.patch
queue-5.15/ksmbd-add-missing-compound-request-handing-in-some-commands.patch
queue-5.15/ksmbd-remove-unused-is_char_allowed-function.patch
queue-5.15/ksmbd-use-oid-registry-functions-to-decode-oids.patch
queue-5.15/ksmbd-fix-kernel-doc-comment-of-ksmbd_vfs_kern_path_locked.patch
queue-5.15/ksmbd-use-wait_event-instead-of-schedule_timeout.patch
queue-5.15/ksmbd-check-if-a-mount-point-is-crossed-during-path-lookup.patch
queue-5.15/ksmbd-replace-the-ternary-conditional-operator-with-min.patch
