{"id":2222821,"url":"http://patchwork.ozlabs.org/api/1.2/patches/2222821/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-cifs-client/patch/20260413191110.1508848-1-henrique.carvalho@suse.com/","project":{"id":12,"url":"http://patchwork.ozlabs.org/api/1.2/projects/12/?format=json","name":"Linux CIFS Client","link_name":"linux-cifs-client","list_id":"linux-cifs.vger.kernel.org","list_email":"linux-cifs@vger.kernel.org","web_url":"","scm_url":"","webscm_url":"","list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20260413191110.1508848-1-henrique.carvalho@suse.com>","list_archive_url":null,"date":"2026-04-13T19:11:09","name":"[1/2] smb: client: serialize channel scaling path","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"0c9ef3e747730e20d3c1e275b8649d3d403ef93c","submitter":{"id":89563,"url":"http://patchwork.ozlabs.org/api/1.2/people/89563/?format=json","name":"Henrique Carvalho","email":"henrique.carvalho@suse.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/linux-cifs-client/patch/20260413191110.1508848-1-henrique.carvalho@suse.com/mbox/","series":[{"id":499742,"url":"http://patchwork.ozlabs.org/api/1.2/series/499742/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-cifs-client/list/?series=499742","date":"2026-04-13T19:11:10","name":"[1/2] smb: client: serialize channel scaling path","version":1,"mbox":"http://patchwork.ozlabs.org/series/499742/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2222821/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2222821/checks/","tags":{},"related":[],"headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linux-cifs@vger.kernel.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=suse.com header.i=@suse.com header.a=rsa-sha256\n header.s=google header.b=OUXumIF8;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=172.105.105.114; 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One of these for each uid session with a particular host\n@@ -1089,7 +1089,7 @@ struct cifs_ses {\n \tbool domainAuto:1;\n \tbool expired_pwd; /* track if access denied or expired pwd so can know if need to update */\n \tint unicode;\n-\tunsigned int flags;\n+\tunsigned long flags;\n \t__u16 session_flags;\n \t__u8 smb3signingkey[SMB3_SIGN_KEY_SIZE];\n \t__u8 smb3encryptionkey[SMB3_ENC_DEC_KEY_SIZE];\ndiff --git a/fs/smb/client/fs_context.c b/fs/smb/client/fs_context.c\nindex a46764c24710..e0e13c22e159 100644\n--- a/fs/smb/client/fs_context.c\n+++ b/fs/smb/client/fs_context.c\n@@ -1166,27 +1166,12 @@ static int smb3_reconfigure(struct fs_context *fc)\n \n \t\t/* Synchronize ses->chan_max with the new mount context */\n \t\tsmb3_sync_ses_chan_max(ses, ctx->max_channels);\n-\t\t/* Now update the session's channels to match the new configuration */\n-\t\t/* Prevent concurrent scaling operations */\n-\t\tspin_lock(&ses->ses_lock);\n-\t\tif (ses->flags & CIFS_SES_FLAG_SCALE_CHANNELS) {\n-\t\t\tspin_unlock(&ses->ses_lock);\n-\t\t\tmutex_unlock(&ses->session_mutex);\n-\t\t\treturn -EINVAL;\n-\t\t}\n-\t\tses->flags |= CIFS_SES_FLAG_SCALE_CHANNELS;\n-\t\tspin_unlock(&ses->ses_lock);\n \n \t\tmutex_unlock(&ses->session_mutex);\n \n \t\trc = smb3_update_ses_channels(ses, ses->server,\n \t\t\t\t\t false /* from_reconnect */,\n \t\t\t\t\t false /* disable_mchan */);\n-\n-\t\t/* Clear scaling flag after operation */\n-\t\tspin_lock(&ses->ses_lock);\n-\t\tses->flags &= ~CIFS_SES_FLAG_SCALE_CHANNELS;\n-\t\tspin_unlock(&ses->ses_lock);\n \t} else {\n \t\tmutex_unlock(&ses->session_mutex);\n \t}\ndiff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c\nindex 5188218c25be..2eb13b2665a4 100644\n--- a/fs/smb/client/smb2pdu.c\n+++ b/fs/smb/client/smb2pdu.c\n@@ -228,6 +228,10 @@ int smb3_update_ses_channels(struct cifs_ses *ses, struct TCP_Server_Info *serve\n \t\t\tbool from_reconnect, bool disable_mchan)\n {\n \tint rc = 0;\n+\n+\tif (test_and_set_bit(CIFS_SES_FLAG_SCALE_CHANNELS, &ses->flags))\n+\t\treturn -EBUSY;\n+\n \t/*\n \t * Manage session channels based on current count vs max:\n \t * - If disable requested, skip or disable the channel\n@@ -243,6 +247,7 @@ int smb3_update_ses_channels(struct cifs_ses *ses, struct TCP_Server_Info *serve\n \t\t\trc = cifs_chan_skip_or_disable(ses, server, from_reconnect, disable_mchan);\n \t}\n \n+\tclear_bit(CIFS_SES_FLAG_SCALE_CHANNELS, &ses->flags);\n \treturn rc;\n }\n \n@@ -432,15 +437,6 @@ smb2_reconnect(__le16 smb2_command, struct cifs_tcon *tcon,\n \t\tgoto out;\n \t}\n \n-\tspin_lock(&ses->ses_lock);\n-\tif (ses->flags & CIFS_SES_FLAG_SCALE_CHANNELS) {\n-\t\tspin_unlock(&ses->ses_lock);\n-\t\tmutex_unlock(&ses->session_mutex);\n-\t\tgoto skip_add_channels;\n-\t}\n-\tses->flags |= CIFS_SES_FLAG_SCALE_CHANNELS;\n-\tspin_unlock(&ses->ses_lock);\n-\n \tif (!rc &&\n \t (server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL) &&\n \t server->ops->query_server_interfaces) {\n@@ -450,11 +446,11 @@ smb2_reconnect(__le16 smb2_command, struct cifs_tcon *tcon,\n \t\t * is in progress. This will be used to avoid calling\n \t\t * smb2_reconnect recursively.\n \t\t */\n-\t\tses->flags |= CIFS_SES_FLAGS_PENDING_QUERY_INTERFACES;\n+\t\tset_bit(CIFS_SES_FLAGS_PENDING_QUERY_INTERFACES, &ses->flags);\n \t\txid = get_xid();\n \t\trc = server->ops->query_server_interfaces(xid, tcon, false);\n \t\tfree_xid(xid);\n-\t\tses->flags &= ~CIFS_SES_FLAGS_PENDING_QUERY_INTERFACES;\n+\t\tclear_bit(CIFS_SES_FLAGS_PENDING_QUERY_INTERFACES, &ses->flags);\n \n \t\tif (!tcon->ipc && !tcon->dummy)\n \t\t\tqueue_delayed_work(cifsiod_wq, &tcon->query_interfaces,\n@@ -492,10 +488,6 @@ smb2_reconnect(__le16 smb2_command, struct cifs_tcon *tcon,\n \t}\n \n skip_add_channels:\n-\tspin_lock(&ses->ses_lock);\n-\tses->flags &= ~CIFS_SES_FLAG_SCALE_CHANNELS;\n-\tspin_unlock(&ses->ses_lock);\n-\n \tif (smb2_command != SMB2_INTERNAL_CMD)\n \t\tcifs_queue_server_reconn(server);\n \n@@ -609,7 +601,7 @@ static int smb2_ioctl_req_init(u32 opcode, struct cifs_tcon *tcon,\n \t */\n \tif (opcode == FSCTL_VALIDATE_NEGOTIATE_INFO ||\n \t (opcode == FSCTL_QUERY_NETWORK_INTERFACE_INFO &&\n-\t (tcon->ses->flags & CIFS_SES_FLAGS_PENDING_QUERY_INTERFACES)))\n+\t test_bit(CIFS_SES_FLAGS_PENDING_QUERY_INTERFACES, &tcon->ses->flags)))\n \t\treturn __smb2_plain_req_init(SMB2_IOCTL, tcon, server,\n \t\t\t\t\t request_buf, total_len);\n \n","prefixes":["1/2"]}