linux-kernel - Re: linux-next: Tree for Apr 20 (objtool warning)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 20 Apr 2020 10:53:30 -0500
From:   Josh Poimboeuf <jpoimboe@...hat.com>
To:     Randy Dunlap <rdunlap@...radead.org>
Cc:     Stephen Rothwell <sfr@...b.auug.org.au>,
        Linux Next Mailing List <linux-next@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Peter Zijlstra <peterz@...radead.org>
Subject: Re: linux-next: Tree for Apr 20 (objtool warning)

On Mon, Apr 20, 2020 at 08:29:04AM -0700, Randy Dunlap wrote:
> On 4/19/20 9:26 PM, Stephen Rothwell wrote:
> > Hi all,
> > 
> > Changes since 20200417:
> > 
> 
> on x86_64:
> 
> arch/x86/kvm/svm/vmenter.o: warning: objtool: __svm_vcpu_run()+0xe4: BP used as a scratch register
> 
> Full randconfig file is included.

Yeah, frame pointers are toast in that function.  We'll need something
like:

diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index a789759b7261..221e2bd7e76d 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -3,6 +3,10 @@
 ccflags-y += -Iarch/x86/kvm
 ccflags-$(CONFIG_KVM_WERROR) += -Werror
 
+ifeq ($(CONFIG_UNWINDER_FRAME_POINTER),y)
+OBJECT_FILES_NON_STANDARD_vmenter.o := y
+endif
+
 KVM := ../../../virt/kvm
 
 kvm-y			+= $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o \