From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?ISO-8859-15?Q?Andr=E9_Hentschel?= Subject: Re: [PATCHv4] arm: Preserve the user r/w register TPIDRURW on context switch and fork Date: Sat, 18 May 2013 17:02:25 +0200 Message-ID: <51979801.7010903@dawncrow.de> References: <518AA19B.2020209@dawncrow.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from moutng.kundenserver.de ([212.227.126.187]:55315 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751743Ab3ERPCb (ORCPT ); Sat, 18 May 2013 11:02:31 -0400 In-Reply-To: <518AA19B.2020209@dawncrow.de> Sender: linux-arch-owner@vger.kernel.org List-ID: To: "linux-arch@vger.kernel.org" Cc: Russell King - ARM Linux , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "gregkh@linuxfoundation.org" , Will Deacon , Jonathan Austin Am 08.05.2013 21:03, schrieb Andr=E9 Hentschel: > From: =3D?UTF-8?q?Andr=3DC3=3DA9=3D20Hentschel?=3D >=20 > Since commit 6a1c53124aa1 the user writeable TLS register was zeroed = to > prevent it from being used as a covert channel between two tasks. >=20 > There are more and more applications coming to WinRT, Wine could supp= ort them, > but mostly they expect to have the thread environment block (TEB) in = TPIDRURW. >=20 > This patch preserves that register per thread instead of clearing it. > Unlike the TPIDRURO, which is already switched, the TPIDRURW > can be updated from userspace so needs careful treatment in the case = that we > modify TPIDRURW and call fork(). To avoid this we must always read > TPIDRURW in copy_thread. >=20 > Signed-off-by: Andr=E9 Hentschel > Signed-off-by: Will Deacon > Signed-off-by: Jonathan Austin =20 >=20 Hi, I'm not yet very familiar with the development process here, am i getting no feedback on v4 because of the mergewindow being closed? Or is there another reason? Sry for being impatient. From mboxrd@z Thu Jan 1 00:00:00 1970 From: nerv@dawncrow.de (=?ISO-8859-15?Q?Andr=E9_Hentschel?=) Date: Sat, 18 May 2013 17:02:25 +0200 Subject: [PATCHv4] arm: Preserve the user r/w register TPIDRURW on context switch and fork In-Reply-To: <518AA19B.2020209@dawncrow.de> References: <518AA19B.2020209@dawncrow.de> Message-ID: <51979801.7010903@dawncrow.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Am 08.05.2013 21:03, schrieb Andr? Hentschel: > From: =?UTF-8?q?Andr=C3=A9=20Hentschel?= > > Since commit 6a1c53124aa1 the user writeable TLS register was zeroed to > prevent it from being used as a covert channel between two tasks. > > There are more and more applications coming to WinRT, Wine could support them, > but mostly they expect to have the thread environment block (TEB) in TPIDRURW. > > This patch preserves that register per thread instead of clearing it. > Unlike the TPIDRURO, which is already switched, the TPIDRURW > can be updated from userspace so needs careful treatment in the case that we > modify TPIDRURW and call fork(). To avoid this we must always read > TPIDRURW in copy_thread. > > Signed-off-by: Andr? Hentschel > Signed-off-by: Will Deacon > Signed-off-by: Jonathan Austin > Hi, I'm not yet very familiar with the development process here, am i getting no feedback on v4 because of the mergewindow being closed? Or is there another reason? Sry for being impatient.