From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yb1-f201.google.com (mail-yb1-f201.google.com [209.85.219.201]) (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 D44B514D428 for ; Wed, 21 Aug 2024 16:12:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724256744; cv=none; b=FxBPE+rfyJeEQChsKZa669BPoZSCdG1C4PfiL9BuKlrdGOWK9ejhdjRDUd0BwChDjFUc4alywRhSD7/QWBOV0T/z0mdjWMdzin/gCLbqdOKJ77MkBxk8zo/Db1nluVWDtmoDP4iUS+BYFSgy3T7O4VxbEGvAiJTdN98FCW0zLjc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724256744; c=relaxed/simple; bh=NydtPMyTP5+oAo+84KseJU7J5BC9FkzuQeOItN+gaK0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=bjtytmC3fn299PEHMQi52406x3+3aQhiEf9pKy2SvVYS2JPQI4P9niaGuk5sX70K5GsTs5msIwBMMbRTAVfNDphbFIh7WCVkIhQKRtpsJ3GjROTRIytmBDmRqPg0tMDKtLehhQFkjgT6h/CeWi8CVDOWKMMQDYpjnrN9ftRKaew= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=sD+1tpzS; arc=none smtp.client-ip=209.85.219.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="sD+1tpzS" Received: by mail-yb1-f201.google.com with SMTP id 3f1490d57ef6-e163641feb9so1869624276.0 for ; Wed, 21 Aug 2024 09:12:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1724256742; x=1724861542; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=zDsQ2kAgROFjamftWGoiLYwkBjJi+WkA8cxHYZSjmNk=; b=sD+1tpzSWxyKMj9Fmn/XSOY+ZsmE5z89omTlkUS2AgaNyyEgR9l8TxytNAczFm1+CI uzyxs5Y79xCc668frnHciN3vI3YpqGueGi2u28KR2Vnwzi1OVppJGXb+b6yCKILJxtyD nSbZ9doI9NQ3LnOWU0SrmmWeK+nY8d8+2emldyovkjmiv8oKY+Mqr0dVoJpx4uxF+sC0 EDXDferh9bcQFuD+oyKOkRmB6RiAZYjt8M2rZOscUdeknq0hDhFa5b6R0bBNwFbvcqzO oMG9pgNB7D/iYuEp3h/7cAUyqMgfn0ph28PhCppPVvjOEOEa+5YxztQlVGLlgYlOrbkM UDvA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724256742; x=1724861542; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=zDsQ2kAgROFjamftWGoiLYwkBjJi+WkA8cxHYZSjmNk=; b=QfI5hIkRKCCoDVlzI9CkGjvBpy3sJjEyMj61PFNn0QuM7X6KiT8LQ2eNl8l0V98g15 HrbONuzq12IHaqlEbsHjqmY+fvmubPonG9Y4T6nQfqVS2vlC8gfTEYuSeCx3T/i36PML 9UfMf8IaZ5+o0K+zxiwHpxyEWoZ2qePdLH0Apkox8cdz9vHoEebWVpjrGJf0NJdvhDQK gEnOtm+vTV7pupXPe16IK2jxNyxrMzPIymPdsIx3tEewbmjB2vlFxy5egHOjfAp5ZNRf K+ktmG6z3RwCXJ49L0wYcN7LdSvrn+NDjtL9sERCLhDAgLDoKMlYLxg3Nq39cZRuje/y O6Qw== X-Gm-Message-State: AOJu0YwcjGLB46E78U/xwAKavKfzr1GwtttFozNzz2u4FW4zcZuvOJVZ fjp7+6uc3hVv/aZnQVsxftgGtxAud13bNl1ezYXL3EOd/YJrfklWXCNp7Ma3+K0Ldbz23q5dNCZ n4w== X-Google-Smtp-Source: AGHT+IEqaDc2zc65jiKfBpI0W8MFg/Dr0sR6Qz6OgjwvTNDFWffOPUsnk4h73GdyvQpXdzjm+oi5UqjhEjE= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a5b:b08:0:b0:e11:757f:30af with SMTP id 3f1490d57ef6-e177652becbmr228276.3.1724256741606; Wed, 21 Aug 2024 09:12:21 -0700 (PDT) Date: Wed, 21 Aug 2024 09:12:20 -0700 In-Reply-To: <20240820230431.3850991-1-kbusch@meta.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240820230431.3850991-1-kbusch@meta.com> Message-ID: Subject: Re: [PATCH RFC] kvm: emulate avx vmovdq From: Sean Christopherson To: Keith Busch Cc: kvm@vger.kernel.org, x86@kernel.org, Keith Busch , Alex Williamson , Paolo Bonzini , Xu Liu Content-Type: text/plain; charset="us-ascii" On Tue, Aug 20, 2024, Keith Busch wrote: > From: Keith Busch > > Because people would like to use this (see "Link"), interpret the VEX Please explicitly call define the use case in the changelog. Yeah, I can follow the link, but I shouldn't have to just to understand that this is the compiler generating vmovdqu for its built-in memcpy(). > prefix and emulate mov instrutions accordingly. The only avx > instructions emulated here are the aligned and unaligned mov. > Everything else will fail as before. > > This is new territory for me, so any feedback is appreciated. Heh, this is probably new territory for everyone except possibly Paolo. I don't recall the last time KVM was effectively forced to add emulation for something this gnarly.