From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3EE9036A03E; Thu, 20 Nov 2025 16:31:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763656283; cv=none; b=RpcKec9g/VYTrY+KXiiLi1Gyxb/ojB3oLC7u9kwsW3KwFRgxXoGA2o72kHCtavW3052PX0Ubol9GR0A4ZnYKfxfZC0yyUZ3HIATFhoksNsjUWYkz8Hqvf/WuKozYqq3WP2aNivCgAU0kztBIG2wAmMK/ls3nGxdg8XQkcm5S7T4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763656283; c=relaxed/simple; bh=2CrS2gfWoeZnSOtpz16jbbv3L/NoFagwPWv505wSGw0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=aAaElE6XeQGAgJSXMWJB1XM20iDYSK0eRnoV56+NV3zD1MK1gW4jnhitOut+/sIQKyq3KFQW1HDIQR3xKZ7sivHHY0rV+mW+6WIs814IcQ21+fAPfLJuC3mY55lKkS/3Ujujx8rmbehgyh2MinXbndeaiDN++T4aw7SGQfNK9lQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IdExhGcO; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="IdExhGcO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C6B58C116C6; Thu, 20 Nov 2025 16:31:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1763656283; bh=2CrS2gfWoeZnSOtpz16jbbv3L/NoFagwPWv505wSGw0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IdExhGcOvHiczH3NH7mnsOZjEIF5Nj4C9u5AZyooJgsjAFcDDEIfYcRBi6CaBgYDn Frg7HdSSk2/GTffiS4yu3eILH89vJk9tEGTxWwoU/TPq1WvNGn+FZA5y3NshMNVCLv piVhEidPsV+pe9umrZoW+xKw8uyXGDqLiHzkiFpVw/OTpKnFVP+jylNrNa3OIKFKcd D+NJWVkWI1yCBGXo3WJZFxthmrPV8o6I3/oaiWVNIz8oJo0+TY4HMgQeQ25ZyVcrk4 gvvQi8tA0Fvog7N+29vqDjAQBB5QUfboxtBuZnqe8ysBlagi4QqLfu9gTpRlwAF8gu 9n2fnbY7ZucRQ== Date: Thu, 20 Nov 2025 16:31:21 +0000 From: Wei Liu To: Uros Bizjak Cc: linux-hyperv@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" Subject: Re: [PATCH 3/3] x86/hyperv: Remove ASM_CALL_CONSTRAINT with VMMCALL insn Message-ID: <20251120163121.GB3330456@liuwe-devbox-debian-v2.local> References: <20251120134105.189753-1-ubizjak@gmail.com> <20251120134105.189753-3-ubizjak@gmail.com> Precedence: bulk X-Mailing-List: linux-hyperv@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251120134105.189753-3-ubizjak@gmail.com> On Thu, Nov 20, 2025 at 02:40:24PM +0100, Uros Bizjak wrote: > Unlike CALL instruction, VMMCALL does not push to the stack, and may be > inserted before the frame pointer gets set up by the containing function. > > Signed-off-by: Uros Bizjak > Cc: "K. Y. Srinivasan" > Cc: Haiyang Zhang > Cc: Wei Liu > Cc: Dexuan Cui > Cc: Thomas Gleixner > Cc: Ingo Molnar > Cc: Borislav Petkov > Cc: Dave Hansen > Cc: "H. Peter Anvin" Dexuan and Tianyu are more qualified than I do to review CVM changes. I will defer this to them. Wei > --- > arch/x86/hyperv/ivm.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c > index 7365d8f43181..be7fad43a88d 100644 > --- a/arch/x86/hyperv/ivm.c > +++ b/arch/x86/hyperv/ivm.c > @@ -392,7 +392,7 @@ u64 hv_snp_hypercall(u64 control, u64 param1, u64 param2) > > register u64 __r8 asm("r8") = param2; > asm volatile("vmmcall" > - : "=a" (hv_status), ASM_CALL_CONSTRAINT, > + : "=a" (hv_status), > "+c" (control), "+d" (param1), "+r" (__r8) > : : "cc", "memory", "r9", "r10", "r11"); > > -- > 2.51.1 >