linux-kernel - Re: [PATCH 1/2] x86/xen: remove 32-bit Xen PV guest support

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, 15 Jul 2019 11:44:42 -0400
From:   Boris Ostrovsky <boris.ostrovsky@...cle.com>
To:     Juergen Gross <jgross@...e.com>, xen-devel@...ts.xenproject.org,
        x86@...nel.org, linux-kernel@...r.kernel.org
Cc:     Andy Lutomirski <luto@...nel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        "H. Peter Anvin" <hpa@...or.com>,
        Stefano Stabellini <sstabellini@...nel.org>
Subject: Re: [PATCH 1/2] x86/xen: remove 32-bit Xen PV guest support


> diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
> index 084de77a109e..d42737f31304 100644
> --- a/arch/x86/xen/Makefile
> +++ b/arch/x86/xen/Makefile
> @@ -1,5 +1,5 @@
>  # SPDX-License-Identifier: GPL-2.0
> -OBJECT_FILES_NON_STANDARD_xen-asm_$(BITS).o := y
> +OBJECT_FILES_NON_STANDARD_xen-asm_64.o := y
>  
>  ifdef CONFIG_FUNCTION_TRACER
>  # Do not profile debug and lowlevel utilities
> @@ -34,7 +34,7 @@ obj-$(CONFIG_XEN_PV)		+= mmu_pv.o
>  obj-$(CONFIG_XEN_PV)		+= irq.o
>  obj-$(CONFIG_XEN_PV)		+= multicalls.o
>  obj-$(CONFIG_XEN_PV)		+= xen-asm.o
> -obj-$(CONFIG_XEN_PV)		+= xen-asm_$(BITS).o
> +obj-$(CONFIG_XEN_PV)		+= xen-asm_64.o

We should be able to merge xen-asm_64.S into xen-asm.S, shouldn't we?


> @@ -1312,15 +1290,7 @@ asmlinkage __visible void __init xen_start_kernel(void)
>  
>  	/* keep using Xen gdt for now; no urgent need to change it */
>  
> -#ifdef CONFIG_X86_32
> -	pv_info.kernel_rpl = 1;
> -	if (xen_feature(XENFEAT_supervisor_mode_kernel))
> -		pv_info.kernel_rpl = 0;
> -#else
>  	pv_info.kernel_rpl = 0;

Is kernel_rpl needed anymore?


-boris