From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71340C77B7D for ; Thu, 18 May 2023 17:22:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229916AbjERRWX (ORCPT ); Thu, 18 May 2023 13:22:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52740 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229924AbjERRWV (ORCPT ); Thu, 18 May 2023 13:22:21 -0400 Received: from mail-il1-x12f.google.com (mail-il1-x12f.google.com [IPv6:2607:f8b0:4864:20::12f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7377210C6 for ; Thu, 18 May 2023 10:22:17 -0700 (PDT) Received: by mail-il1-x12f.google.com with SMTP id e9e14a558f8ab-331430faba8so6134315ab.3 for ; Thu, 18 May 2023 10:22:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1684430537; x=1687022537; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=P5a2wI1V2krLoc2oF7CZW7cpXkFwJvYuHvRdWhIKbTc=; b=ipr7syLJwwQeUwFaCNusUM+A9CdYg0Fqil/Z3knRuyPSy84hWRYGy5PJODlUAGER+j 77hx09aTZL7+OFSEsEj3l2UxH8f+vGoS3kJAX+MkpExqFcKPEF8jK9xlPsbYpdPyb0uA Hmq3k+oCifj/Pkbt/CDlxgKRngYnB1i6YP16w= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684430537; x=1687022537; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=P5a2wI1V2krLoc2oF7CZW7cpXkFwJvYuHvRdWhIKbTc=; b=FkiVf8NifpcvE76JSBjiilQ35Qk4j8agqHUh13OUQ68kcQxRbRCt4fk0W1jxgUffBy 8ESUTGvek0cYzCW9OXQY6mr+HLTGXymROgDSUNXOR2XC/FbkEg+nOVPOSrpYbRUiML1G 5sJiVlLHWNv7Y1XjQDkbcYJgQRWnh+1A6TV7f94JYHh+/mWtAS3dJ6kR31jDdbw30u+y U9UwSaXsO7ylf6mcKDOCq0IuudYTGrfkrTS6pcoePNwerQke0kf9HZISJ6bHAuI+vEG4 /4fbiW8AWPgfMq98Lirm7hsAwcjERBANlfKBQo6fHK+IotHiCJRDAoj6uUmmUcMVBu6o TFZw== X-Gm-Message-State: AC+VfDyujZREj8ljYpV7kVu9CJrBWa2YMyrUp2fBohRpF92TbeRgT32S SN7XXgxn0+Ayocu8qFP1YbL/E8gEgKGknXGrys02rQ== X-Google-Smtp-Source: ACHHUZ60P76B2UzzbBK193S6gb6OmCgSJ+O/0JW5zVfK+OxNhkR0td6SUVsLemXmPqSu1/WFqahGuQ== X-Received: by 2002:a92:d5c1:0:b0:335:56cb:a3a with SMTP id d1-20020a92d5c1000000b0033556cb0a3amr4754220ilq.16.1684430536831; Thu, 18 May 2023 10:22:16 -0700 (PDT) Received: from google.com (h24-56-189-219.arvdco.broadband.dynamic.tds.net. [24.56.189.219]) by smtp.gmail.com with ESMTPSA id bp19-20020a056638441300b00411be337516sm605398jab.24.2023.05.18.10.22.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 May 2023 10:22:16 -0700 (PDT) Date: Thu, 18 May 2023 11:22:14 -0600 From: Raul E Rangel To: Dmitry Torokhov Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 5/7] Input: libps2 - fix aborting PS/2 commands Message-ID: References: <20230511185252.386941-1-dmitry.torokhov@gmail.com> <20230511185252.386941-6-dmitry.torokhov@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230511185252.386941-6-dmitry.torokhov@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org On Thu, May 11, 2023 at 11:52:45AM -0700, Dmitry Torokhov wrote: > When aborting PS/2 command the kernel should [re]set all flags before > waking up waiters, otherwise waiting thread may read obsolete values > of flags. > > Reported-by: Raul Rangel > Signed-off-by: Dmitry Torokhov > --- > drivers/input/serio/libps2.c | 15 +++++++++++---- > 1 file changed, 11 insertions(+), 4 deletions(-) > > diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c > index 14b70a78875d..09eb605364bb 100644 > --- a/drivers/input/serio/libps2.c > +++ b/drivers/input/serio/libps2.c > @@ -478,15 +478,22 @@ bool ps2_handle_response(struct ps2dev *ps2dev, u8 data) > } > EXPORT_SYMBOL(ps2_handle_response); > > +/* > + * Clears state of PS/2 device after communication error by resetting majority > + * of flags and waking up waiters, if any. > + */ > void ps2_cmd_aborted(struct ps2dev *ps2dev) > { > - if (ps2dev->flags & PS2_FLAG_ACK) > + unsigned long old_flags = ps2dev->flags; > + > + /* reset all flags except last nak */ > + ps2dev->flags &= PS2_FLAG_NAK; > + > + if (old_flags & PS2_FLAG_ACK) > ps2dev->nak = 1; > > - if (ps2dev->flags & (PS2_FLAG_ACK | PS2_FLAG_CMD)) > + if (old_flags & (PS2_FLAG_ACK | PS2_FLAG_CMD)) > wake_up(&ps2dev->wait); > > - /* reset all flags except last nack */ > - ps2dev->flags &= PS2_FLAG_NAK; > } > EXPORT_SYMBOL(ps2_cmd_aborted); Reviewed-by: Raul E Rangel