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[193.116.97.30]) by smtp.gmail.com with ESMTPSA id 6sm39988438pfj.216.2020.12.29.18.33.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 29 Dec 2020 18:33:08 -0800 (PST) Date: Wed, 30 Dec 2020 12:33:02 +1000 From: Nicholas Piggin Subject: Re: [RFC please help] membarrier: Rewrite sync_core_before_usermode() To: Russell King - ARM Linux admin References: <20201228102537.GG1551@shell.armlinux.org.uk> <20201228190852.GI1551@shell.armlinux.org.uk> <1086654515.3607.1609187556216.JavaMail.zimbra@efficios.com> <1609200902.me5niwm2t6.astroid@bobo.none> <1609210162.4d8dqilke6.astroid@bobo.none> <20201229104456.GK1551@shell.armlinux.org.uk> In-Reply-To: <20201229104456.GK1551@shell.armlinux.org.uk> MIME-Version: 1.0 Message-Id: <1609290821.wrfh89v23a.astroid@bobo.none> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201229_213313_518586_00690597 X-CRM114-Status: GOOD ( 22.82 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: paulmck , Arnd Bergmann , Jann Horn , Peter Zijlstra , Benjamin Herrenschmidt , x86 , linux-kernel , stable , Will Deacon , Mathieu Desnoyers , Michael Ellerman , Andy Lutomirski , Catalin Marinas , Paul Mackerras , linuxppc-dev , linux-arm-kernel Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org RXhjZXJwdHMgZnJvbSBSdXNzZWxsIEtpbmcgLSBBUk0gTGludXggYWRtaW4ncyBtZXNzYWdlIG9m IERlY2VtYmVyIDI5LCAyMDIwIDg6NDQgcG06Cj4gT24gVHVlLCBEZWMgMjksIDIwMjAgYXQgMDE6 MDk6MTJQTSArMTAwMCwgTmljaG9sYXMgUGlnZ2luIHdyb3RlOgo+PiBJIHRoaW5rIGl0IHNob3Vs ZCBjZXJ0YWlubHkgYmUgZG9jdW1lbnRlZCBpbiB0ZXJtcyBvZiB3aGF0IGd1YXJhbnRlZXMKPj4g aXQgcHJvdmlkZXMgdG8gYXBwbGljYXRpb24sIF9ub3RfIHRoZSBraW5kcyBvZiBpbnN0cnVjdGlv 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