From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f181.google.com (mail-pg1-f181.google.com [209.85.215.181]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9E915324B33 for ; Sun, 30 Aug 2026 20:52:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788123181; cv=none; b=J+w2bOYoni/Dy6FIun+OcPHWR0cVteQ87iTySNbwT5bnjSujVIQ0WhQuzxl4JteAo92LZqEBvgX+hFvk6yBV7RW40vl6iBLWm7r8Ml2jOT1eKgochsQRmV9eTogeC2xTo47ha+jOUtwM+p2Xi2EdrCM6ZCCdBpp2EXP8oy/iza4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788123181; c=relaxed/simple; bh=GXnE++8ycCQ3Geyc1VEaJivw863kljbsemhtvc2XkW0=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=HFTDmcZMptJnN3nqhoxrs3stCDhliMDoYBHe6AJigRUHz+7W2pHQFg2FLS/CxUzgbsjt4g0GxJSccY0YSQG9TApn3hQq6BZe37df0YZJG8zEAF4Yy8bhsKvrdQLHrXuESuk19G/SomOh4MXjoKeIDrgJvvcC3hnPIIxt5EsH/hw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=LMIlAmQv; arc=none smtp.client-ip=209.85.215.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LMIlAmQv" Received: by mail-pg1-f181.google.com with SMTP id 41be03b00d2f7-cc1c7364550so2924012a12.1 for ; Sun, 30 Aug 2026 13:52:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1788123176; x=1788727976; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :content-type:mime-version:subject:date:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=6Dq60Pyzo1OLSy7MU+OaidMLABdeC4LX97otWKe9Wa0=; b=LMIlAmQvTa8F1O3iDv4z56PI9Z8qth5rgwpOm6Het98hLwadf5fDHBEqJ5dgss9zLz 3OU7PZ7alooHd3aI5tx5ju1cNQkBKB1w8No5eV1K51x1egwwxWxkTfpeRGY8wEyZ/H9C V9iO9Xpn3U+J7Mh5TfSt5JjS6G99sdmUwjvkmSPVhz2sNzKZ6ECyKJO6lkLiyzCQ744t V+xuuIj734Jt91jZiTDb1b2TJo1TppDPuo6JpLRKUTnXzPO1kuG8/4+Gc5lvAv+olpMV WNCsqd5IgTq03vuSoGv1QgDxR+6AlkNTOOOHAs0eo3D6c8eTfZMqgyQXMg4ZNpTLL0WD EEhA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788123176; x=1788727976; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :content-type:mime-version:subject:date:from:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=6Dq60Pyzo1OLSy7MU+OaidMLABdeC4LX97otWKe9Wa0=; b=E/2Awv/+TkizK/7uKZlNYEAZBFcmbl+74lChN9CfsKhl0ahM7VOyNjKoS8U+aZD+1v +H29Wfr+Gj73y9W1uxsDuOiAh+ZSLC0FBUJY6HWQF4qAZjeuJOuVju8BCrtBIerp1jXw SgjtDKxlilBMk24mIW6VKiLZhImG17Ql5f0AP6cX6GSq1x8D5bCgdtW6YBq+ApP+Xotu zC+IyG1A21Yx5l3XCLn2VbnbHx6a2b9ttiW2IY4Fc4y0kdEkxxPemT7J2+RRhiAf2QG1 /OUCbIMEI+L8t6xo3CxqAzSXCO/+6A024Ak5OjoLty5XmNaUJ8em7Cy+KoLd497O+RL5 ubgQ== X-Gm-Message-State: AFuF++kXR85lKT/twuum44fsRLvwQh8/TxmFUlULRgpzVWikgEoNLvdx GEvp/8D3UMG8B4kA90wITtxu2BPSMgkGXsyOtqhk8sy73CCGvvk/rlQpfFkzqE6X X-Gm-Gg: AYBFou3NyHCzTASbgwne5AzCe7vfInpilI+/bU7Z430zaYKEx21YQqaEbsooFeBsN7r tiEg4h+QmeTEpW3lC+UkVVAZXStFYBAcut+HoWrt6OsQ6WkVGMxESzCfDBib3jRilaxh9TQw0t/ pSqoVSOUs3FEcmPROpAyr6Aihk+PBRmqjrNaI+HuH3F2JdtK90U02Pp1tmmMMC0Yte4P61UFD6o diJEnXgMRMKgH8gcpC8dLoRv6YSncU+DF5Lua1vm6RGogB6sWc6+5V5FCnWEdMzhPfsH7NFOGiE 3GONifl6bnpfZE+7h8z9A93mcF+kiPK/xDt4ailLeA1Nt5/Q0/gfyGDTPqVsLagPgPbe+pVA2vD IcJlLEp4TGi2ZTjm4r5nZnP5Grcwd+vcdFgWB80I9Gc+96enTJnvPv6sp2E0BAnjrByu+S/upjB 5PouPEpuDHEYnUxmm6byv8b0rZMhNNEul2SQWfgN+7hJ1Egc2zljOZWsV6kRaQYfNxGFj9qas5D vb0i4RNnhUDVSwvM6bvcDvbHthhocsejba8HyFpTKaZd44pl6A= X-Received: by 2002:a17:90b:3812:b0:398:b71e:60c1 with SMTP id 98e67ed59e1d1-398b71e6250mr11845600a91.12.1788123176445; Sun, 30 Aug 2026 13:52:56 -0700 (PDT) Received: from dtor-ws.sjc.corp.google.com ([2a00:79e0:2ebe:8:c021:485f:75be:3c7]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-3286f9e3cf8sm26849437eec.24.2026.08.30.13.52.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 30 Aug 2026 13:52:54 -0700 (PDT) From: Dmitry Torokhov Date: Sun, 30 Aug 2026 13:52:47 -0700 Subject: [PATCH 2/7] Input: gscps2 - use RCU for ps2port_list and manage it in open/close Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260830-gscps2-v1-2-c733d4cae7f9@gmail.com> References: <20260830-gscps2-v1-0-c733d4cae7f9@gmail.com> In-Reply-To: <20260830-gscps2-v1-0-c733d4cae7f9@gmail.com> To: "James E.J. Bottomley" , Helge Deller Cc: linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, linux-parisc@vger.kernel.org, sashiko-bot@kernel.org X-Mailer: b4 0.16-dev-b242f Managing ps2port_list in gscps2_probe() and gscps2_remove() had two issues: - in gscps2_remove(), serio_unregister_port() frees the serio port, but because the port remained in ps2port_list until later in remove, a shared interrupt firing on another CPU could traverse ps2port_list and dereference the freed serio port - ps2port_list additions and deletions in probe/remove raced locklessly against list traversals in gscps2_interrupt(). Convert ps2port_list traversal in gscps2_interrupt() to use RCU, and move list management to gscps2_open() and gscps2_close(). When serio_unregister_port() runs during device removal, serio_close() is invoked, cleanly taking the port out of ps2port_list before the serio structure is destroyed, while maintaining active hardware communication during child driver disconnect. Reported-by: sashiko-bot@kernel.org Assisted-by: LLM Signed-off-by: Dmitry Torokhov --- drivers/input/serio/gscps2.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) diff --git a/drivers/input/serio/gscps2.c b/drivers/input/serio/gscps2.c index b82c56ba8ff7..5b6e311f8a02 100644 --- a/drivers/input/serio/gscps2.c +++ b/drivers/input/serio/gscps2.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -195,6 +196,7 @@ struct gscps2port { int id; }; +static DEFINE_SPINLOCK(ps2port_list_lock); static LIST_HEAD(ps2port_list); /* @@ -292,14 +294,16 @@ static irqreturn_t gscps2_interrupt(int irq, void *dev) { struct gscps2port *ps2port; - list_for_each_entry(ps2port, &ps2port_list, node) { + guard(rcu)(); + + list_for_each_entry_rcu(ps2port, &ps2port_list, node) { guard(spinlock_irqsave)(&ps2port->lock); gscps2_read_data(ps2port); - } /* list_for_each_entry */ + } /* all data was read from the ports - now report the data to upper layer */ - list_for_each_entry(ps2port, &ps2port_list, node) { + list_for_each_entry_rcu(ps2port, &ps2port_list, node) { if (gscps2_report_data(ps2port)) { /* More data ready - break early to restart interrupt */ break; @@ -397,6 +401,9 @@ static int gscps2_open(struct serio *port) gscps2_reset(ps2port); + scoped_guard(spinlock_irqsave, &ps2port_list_lock) + list_add_tail_rcu(&ps2port->node, &ps2port_list); + /* enable it */ gscps2_enable(ps2port, true); @@ -413,6 +420,11 @@ static void gscps2_close(struct serio *port) struct gscps2port *ps2port = port->port_data; gscps2_enable(ps2port, false); + + scoped_guard(spinlock_irqsave, &ps2port_list_lock) + list_del_rcu(&ps2port->node); + + synchronize_rcu(); } /** @@ -446,6 +458,7 @@ static int __init gscps2_probe(struct parisc_device *dev) ps2port->port = serio; ps2port->padev = dev; + INIT_LIST_HEAD(&ps2port->node); ps2port->addr = ioremap(hpa, GSC_STATUS + 4); if (!ps2port->addr) { ret = -ENOMEM; @@ -501,8 +514,6 @@ static int __init gscps2_probe(struct parisc_device *dev) serio_register_port(ps2port->port); - list_add_tail(&ps2port->node, &ps2port_list); - return 0; fail: @@ -539,12 +550,10 @@ static void __exit gscps2_remove(struct parisc_device *dev) serio_unregister_port(ps2port->port); free_irq(dev->irq, ps2port); gscps2_flush(ps2port); - list_del(&ps2port->node); iounmap(ps2port->addr); #if 0 release_mem_region(dev->hpa, GSC_STATUS + 4); #endif - dev_set_drvdata(&dev->dev, NULL); kfree(ps2port); } -- 2.55.0.897.gb25b4bd76c-goog