From: Peter Zijlstra <peterz@infradead.org>
Date: Fri, 23 Feb 2018 10:41:53 +0000 (+0100)
Subject: KVM: VMX: Make indirect call speculation safe
X-Git-Tag: v4.4.118~28
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d5030418b0c82956921545121b4f08df0f9ece70;p=thirdparty%2Fkernel%2Fstable.git

KVM: VMX: Make indirect call speculation safe

(cherry picked from commit c940a3fb1e2e9b7d03228ab28f375fb5a47ff699)

Replace indirect call with CALL_NOSPEC.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Jun Nakajima <jun.nakajima@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: rga@amazon.de
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Link: https://lkml.kernel.org/r/20180125095843.645776917@infradead.org
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[backport to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 2a1a8737015b8..7e653ec47da86 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -8377,13 +8377,13 @@ static void vmx_handle_external_intr(struct kvm_vcpu *vcpu)
 			"pushf\n\t"
 			"orl $0x200, (%%" _ASM_SP ")\n\t"
 			__ASM_SIZE(push) " $%c[cs]\n\t"
-			"call *%[entry]\n\t"
+			CALL_NOSPEC
 			:
 #ifdef CONFIG_X86_64
 			[sp]"=&r"(tmp)
 #endif
 			:
-			[entry]"r"(entry),
+			THUNK_TARGET(entry),
 			[ss]"i"(__KERNEL_DS),
 			[cs]"i"(__KERNEL_CS)
 			);