From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EAE9746AF32 for ; Tue, 28 Apr 2026 13:19:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777382351; cv=none; b=F8GIvYXB3Zb4ezL8M6AmThefwm6+mhFrnrPGsRkUDgeEyuhjgX3f9YFn2Un2bElbiV8z2/ZF14OdR2DE0thTJfr0eUI2fwABDjpFmcArB8RRM4yCgNQ/HGkjD6ELoPSMZBt68Fz+Zbaif3EGtW6Nu83VNekxEqeZzbNV6i3rsHs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777382351; c=relaxed/simple; bh=xKMwK6XyTR2S1NYi1ll51KBolxqfDxdt7e/1pyWESn8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=T+6cUGZaF13nI4oXpxCz9A1xy0tJ0M8Ohk4EVJNkU1nxztLN3qd7fJhIRaUd/9RSfYuWd2wZ8oJiGOlfemM+i9pDhVCI9wnmQotiMEzyijbI/EczjJLqS/1iGRLPwKrnm+94YUf5m/zV79vd4WsY9iXNvVrvR4HO7Agsaj/Q4ZA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=Rw8QePfe; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Rw8QePfe" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1777382349; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=I9C1Tq0bWPjxQKHy18dUxRo+Gdg144k5WV4DnkH5buY=; b=Rw8QePfesTfhsWQuEXy7zoEb5MpJcUPzdszfpHIEafTfI4td4NwU6wK2hRNAtKOuvq4F/E 8Aayb9IYwKjkVjic2RC8n3JvRRKXDO009RsOQ8SVzOWdqvje10cZmDyZw6BfLVBVt4ylwz 1Q78mHCFaPpqBIaZ4UpM3VXhVLW4ds0= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-341-53Ejn19wPNSPVfWSlsUvmQ-1; Tue, 28 Apr 2026 09:19:03 -0400 X-MC-Unique: 53Ejn19wPNSPVfWSlsUvmQ-1 X-Mimecast-MFC-AGG-ID: 53Ejn19wPNSPVfWSlsUvmQ_1777382341 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id AC63E18B7CE3; Tue, 28 Apr 2026 13:18:12 +0000 (UTC) Received: from warthog.procyon.org.com (unknown [10.44.32.126]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 6E3771800348; Tue, 28 Apr 2026 13:18:08 +0000 (UTC) From: David Howells To: Christian Brauner Cc: David Howells , Paulo Alcantara , netfs@lists.linux.dev, linux-afs@lists.infradead.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 02/24] netfs: Fix missing locking around retry adding new subreqs Date: Tue, 28 Apr 2026 14:17:32 +0100 Message-ID: <20260428131756.922303-3-dhowells@redhat.com> In-Reply-To: <20260428131756.922303-1-dhowells@redhat.com> References: <20260428131756.922303-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Fix netfs_retry_read_subrequests() and netfs_retry_write_stream() to take the appropriate lock when adding extra subrequests into stream->subrequests. Fixes: e2d46f2ec332 ("netfs: Change the read result collector to only use one work item") Fixes: 288ace2f57c9 ("netfs: New writeback implementation") Closes: https://sashiko.dev/#/patchset/20260425125426.3855807-1-dhowells%40redhat.com Signed-off-by: David Howells cc: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org --- fs/netfs/read_retry.c | 6 +++++- fs/netfs/write_retry.c | 6 +++++- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/fs/netfs/read_retry.c b/fs/netfs/read_retry.c index cca9ac43c077..5ec548b996d6 100644 --- a/fs/netfs/read_retry.c +++ b/fs/netfs/read_retry.c @@ -175,7 +175,9 @@ static void netfs_retry_read_subrequests(struct netfs_io_request *rreq) list_for_each_entry_safe_from(subreq, tmp, &stream->subrequests, rreq_link) { trace_netfs_sreq(subreq, netfs_sreq_trace_superfluous); + spin_lock(&rreq->lock); list_del(&subreq->rreq_link); + spin_unlock(&rreq->lock); netfs_put_subrequest(subreq, netfs_sreq_trace_put_done); if (subreq == to) break; @@ -203,8 +205,10 @@ static void netfs_retry_read_subrequests(struct netfs_io_request *rreq) refcount_read(&subreq->ref), netfs_sreq_trace_new); + spin_lock(&rreq->lock); list_add(&subreq->rreq_link, &to->rreq_link); - to = list_next_entry(to, rreq_link); + spin_unlock(&rreq->lock); + to = subreq; trace_netfs_sreq(subreq, netfs_sreq_trace_retry); stream->sreq_max_len = umin(len, rreq->rsize); diff --git a/fs/netfs/write_retry.c b/fs/netfs/write_retry.c index 29489a23a220..32735abfa03f 100644 --- a/fs/netfs/write_retry.c +++ b/fs/netfs/write_retry.c @@ -130,7 +130,9 @@ static void netfs_retry_write_stream(struct netfs_io_request *wreq, list_for_each_entry_safe_from(subreq, tmp, &stream->subrequests, rreq_link) { trace_netfs_sreq(subreq, netfs_sreq_trace_discard); + spin_lock(&wreq->lock); list_del(&subreq->rreq_link); + spin_unlock(&wreq->lock); netfs_put_subrequest(subreq, netfs_sreq_trace_put_done); if (subreq == to) break; @@ -153,8 +155,10 @@ static void netfs_retry_write_stream(struct netfs_io_request *wreq, netfs_sreq_trace_new); trace_netfs_sreq(subreq, netfs_sreq_trace_split); + spin_lock(&wreq->lock); list_add(&subreq->rreq_link, &to->rreq_link); - to = list_next_entry(to, rreq_link); + spin_unlock(&wreq->lock); + to = subreq; trace_netfs_sreq(subreq, netfs_sreq_trace_retry); stream->sreq_max_len = len;