From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Howells Date: Thu, 06 Jun 2019 22:52:50 +0000 Subject: Re: [PATCH 10/10] Add sample notification program [ver #3] Message-Id: <31575.1559861570@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit List-Id: References: <20190606212140.GA25664@vmlxhi-102.adit-jv.com> <155981411940.17513.7137844619951358374.stgit@warthog.procyon.org.uk> <155981421379.17513.13158528501056454772.stgit@warthog.procyon.org.uk> In-Reply-To: <20190606212140.GA25664@vmlxhi-102.adit-jv.com> To: Eugeniu Rosca Cc: dhowells@redhat.com, viro@zeniv.linux.org.uk, raven@themaw.net, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-block@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, Eugeniu Rosca Eugeniu Rosca wrote: > How about arm64? Do you intend to enable cross-compilation? There's no guarantee that a cross-compiler can actually build userspace apps, though I haven't intended to encode anything against that in the Makefile. > > + asm ("lfence" : : : "memory" ); > [..] > > + asm("mfence" ::: "memory"); > > FWIW, trying to cross-compile it returned: > > aarch64-linux-gnu-gcc -I../../usr/include -I../../include watch_test.c -o watch_test > /tmp/ccDXYynm.s: Assembler messages: > /tmp/ccDXYynm.s:471: Error: unknown mnemonic `lfence' -- `lfence' > /tmp/ccDXYynm.s:568: Error: unknown mnemonic `mfence' -- `mfence' Yeah. I need to use C-standard __atomic_* stuff. David