From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x224k9JIS1wDpGpOpH3lC4l29Th0NF6Dw2bHrFCaXGwVLIRXGjdwBXCE/dz/gB+QOPCebiCdw ARC-Seal: i=1; a=rsa-sha256; t=1516721578; cv=none; d=google.com; s=arc-20160816; b=qD0nmQQNy76m7GHKsEGwF6t8aHc2URHO5748/+XVdAn995a9vO7Fm90HZ/ncOzuWE4 rm+HfZxLkQ4ztOrEVVmf1BOI/GLW4cCWeFpdJXatm/2xyE7AGGu1SOkSYcfn5XaNJvgZ j/rHLf0Iz/+GqPykyQnZzLi5gDM0ai1YO25STd/2sTIE0L9StWMyjimf99wXsgOmXj3U p3MGS4aycZYDtL4Ja3kUSmKVB3clo7io/xpvbjCjyCmt2vhFZum9FbiIqgYPHq3Oz5Kw BlqizsH5DiwQVgQ8SPLwFCnBPMZ7zOT6vsWR30hBAgocu/1DeqbSzM0A4vB5zBmWf5Y8 wmGQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-disposition:mime-version:references:subject:cc:to:from:date :user-agent:message-id:dkim-signature:arc-authentication-results; bh=h9kWFOigLB4PmmKjjxm0X1cXCyNF0KZVi20f8Fh2EG0=; b=wacA0HRY2avpcCQcdysZ2W1U5roIQyTHCVMiEZlcII7oUTcaCJl/tQN51KlK5B/ySd BfwTyeypG7Le0xDrQeFGQR3x12XU2TZAvzqqW2uEHK0VUH7igC8FujPmuWI4Qon6j68w Lul2e2ZgRsDoSjhg8Wfx1mqPc4ZQ25ncvW/k9Tti+lIKIWzRNNqCwvJ/8vjLqShP0m1D +TXPY+GeBVlKJ3fTffkVOgCL9GWoq8m1fo8aDiEycjuQpkVvkeVKVBk3M7/aFiTItDVF ZLqRwtpFtKljc4DGSWaawob+Ap9vPRlQoltojEEMfNxudmqYfnSwg6RHF4OLrUPIcxLL HjcQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=bombadil.20170209 header.b=XnH2eujt; spf=pass (google.com: best guess record for domain of peterz@infradead.org designates 65.50.211.133 as permitted sender) smtp.mailfrom=peterz@infradead.org Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=bombadil.20170209 header.b=XnH2eujt; spf=pass (google.com: best guess record for domain of peterz@infradead.org designates 65.50.211.133 as permitted sender) smtp.mailfrom=peterz@infradead.org Message-Id: <20180123152638.336674335@infradead.org> User-Agent: quilt/0.63-1 Date: Tue, 23 Jan 2018 16:25:45 +0100 From: Peter Zijlstra To: David Woodhouse , Thomas Gleixner , Josh Poimboeuf Cc: linux-kernel@vger.kernel.org, Dave Hansen , Ashok Raj , Tim Chen , Andy Lutomirski , Linus Torvalds , Greg KH , Andrea Arcangeli , Andi Kleen , Arjan Van De Ven , Dan Williams , Paolo Bonzini , Jun Nakajima , Asit Mallick , Jason Baron , Peter Zijlstra Subject: [PATCH 06/24] x86,kvm: Fix indirect calls in emulator References: <20180123152539.374360046@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline; filename=peterz-kvm-retpoline.patch X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1590397846081548237?= X-GMAIL-MSGID: =?utf-8?q?1590397846081548237?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Replace the indirect calls with CALL_NOSPEC. Cc: Paolo Bonzini Signed-off-by: Peter Zijlstra (Intel) --- arch/x86/kvm/emulate.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -25,6 +25,7 @@ #include #include #include +#include #include "x86.h" #include "tss.h" @@ -1021,8 +1022,8 @@ static __always_inline u8 test_cc(unsign void (*fop)(void) = (void *)em_setcc + 4 * (condition & 0xf); flags = (flags & EFLAGS_MASK) | X86_EFLAGS_IF; - asm("push %[flags]; popf; call *%[fastop]" - : "=a"(rc) : [fastop]"r"(fop), [flags]"r"(flags)); + asm("push %[flags]; popf; " CALL_NOSPEC + : "=a"(rc) : [thunk_target]"r"(fop), [flags]"r"(flags)); return rc; } @@ -5305,9 +5306,9 @@ static int fastop(struct x86_emulate_ctx if (!(ctxt->d & ByteOp)) fop += __ffs(ctxt->dst.bytes) * FASTOP_SIZE; - asm("push %[flags]; popf; call *%[fastop]; pushf; pop %[flags]\n" + asm("push %[flags]; popf; " CALL_NOSPEC " ; pushf; pop %[flags]\n" : "+a"(ctxt->dst.val), "+d"(ctxt->src.val), [flags]"+D"(flags), - [fastop]"+S"(fop), ASM_CALL_CONSTRAINT + [thunk_target]"+S"(fop), ASM_CALL_CONSTRAINT : "c"(ctxt->src2.val)); ctxt->eflags = (ctxt->eflags & ~EFLAGS_MASK) | (flags & EFLAGS_MASK);