[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20170718223333.110371-6-thgarnie@google.com>
Date: Tue, 18 Jul 2017 15:33:16 -0700
From: Thomas Garnier <thgarnie@...gle.com>
To: Herbert Xu <herbert@...dor.apana.org.au>,
"David S . Miller" <davem@...emloft.net>,
Thomas Gleixner <tglx@...utronix.de>,
Ingo Molnar <mingo@...hat.com>,
"H . Peter Anvin" <hpa@...or.com>,
Peter Zijlstra <peterz@...radead.org>,
Josh Poimboeuf <jpoimboe@...hat.com>,
Thomas Garnier <thgarnie@...gle.com>,
Arnd Bergmann <arnd@...db.de>,
Matthias Kaehlcke <mka@...omium.org>,
Boris Ostrovsky <boris.ostrovsky@...cle.com>,
Juergen Gross <jgross@...e.com>,
Paolo Bonzini <pbonzini@...hat.com>,
Radim Krčmář <rkrcmar@...hat.com>,
Joerg Roedel <joro@...tes.org>,
Andy Lutomirski <luto@...nel.org>,
Borislav Petkov <bp@...en8.de>,
"Kirill A . Shutemov" <kirill.shutemov@...ux.intel.com>,
Brian Gerst <brgerst@...il.com>,
Borislav Petkov <bp@...e.de>,
Christian Borntraeger <borntraeger@...ibm.com>,
"Rafael J . Wysocki" <rjw@...ysocki.net>,
Len Brown <len.brown@...el.com>,
Pavel Machek <pavel@....cz>,
Tejun Heo <tj@...nel.org>,
Christoph Lameter <cl@...ux.com>,
Kees Cook <keescook@...omium.org>,
Paul Gortmaker <paul.gortmaker@...driver.com>,
Chris Metcalf <cmetcalf@...lanox.com>,
"Paul E . McKenney" <paulmck@...ux.vnet.ibm.com>,
Andrew Morton <akpm@...ux-foundation.org>,
Christopher Li <sparse@...isli.org>,
Dou Liyang <douly.fnst@...fujitsu.com>,
Masahiro Yamada <yamada.masahiro@...ionext.com>,
Daniel Borkmann <daniel@...earbox.net>,
Markus Trippelsdorf <markus@...ppelsdorf.de>,
Peter Foley <pefoley2@...oley.com>,
Steven Rostedt <rostedt@...dmis.org>,
Tim Chen <tim.c.chen@...ux.intel.com>,
Ard Biesheuvel <ard.biesheuvel@...aro.org>,
Catalin Marinas <catalin.marinas@....com>,
Matthew Wilcox <mawilcox@...rosoft.com>,
Michal Hocko <mhocko@...e.com>,
Rob Landley <rob@...dley.net>,
Jiri Kosina <jkosina@...e.cz>,
"H . J . Lu" <hjl.tools@...il.com>,
Paul Bolle <pebolle@...cali.nl>,
Baoquan He <bhe@...hat.com>,
Daniel Micay <danielmicay@...il.com>
Cc: x86@...nel.org,
linux-crypto@...r.kernel.org,
linux-kernel@...r.kernel.org,
xen-devel@...ts.xenproject.org,
kvm@...r.kernel.org,
linux-pm@...r.kernel.org,
linux-arch@...r.kernel.org,
linux-sparse@...r.kernel.org,
kernel-hardening@...ts.openwall.com
Subject: [RFC 05/22] xen: Adapt assembly for PIE support
Change the assembly code to use the new _ASM_GET_PTR macro which get a
symbol reference while being PIE compatible. Modify the RELOC macro that
was using an assignment generating a non-relative reference.
Position Independent Executable (PIE) support will allow to extended the
KASLR randomization range below the -2G memory limit.
Signed-off-by: Thomas Garnier <thgarnie@...gle.com>
---
arch/x86/xen/xen-asm.h | 3 ++-
arch/x86/xen/xen-head.S | 9 +++++----
2 files changed, 7 insertions(+), 5 deletions(-)
diff --git a/arch/x86/xen/xen-asm.h b/arch/x86/xen/xen-asm.h
index 465276467a47..3b1c8a2e77d8 100644
--- a/arch/x86/xen/xen-asm.h
+++ b/arch/x86/xen/xen-asm.h
@@ -2,8 +2,9 @@
#define _XEN_XEN_ASM_H
#include <linux/linkage.h>
+#include <asm/asm.h>
-#define RELOC(x, v) .globl x##_reloc; x##_reloc=v
+#define RELOC(x, v) .globl x##_reloc; x##_reloc: _ASM_PTR v
#define ENDPATCH(x) .globl x##_end; x##_end=.
/* Pseudo-flag used for virtual NMI, which we don't implement yet */
diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S
index 72a8e6adebe6..ab2462396bd8 100644
--- a/arch/x86/xen/xen-head.S
+++ b/arch/x86/xen/xen-head.S
@@ -23,14 +23,15 @@ ENTRY(startup_xen)
/* Clear .bss */
xor %eax,%eax
- mov $__bss_start, %_ASM_DI
- mov $__bss_stop, %_ASM_CX
+ _ASM_GET_PTR(__bss_start, %_ASM_DI)
+ _ASM_GET_PTR(__bss_stop, %_ASM_CX)
sub %_ASM_DI, %_ASM_CX
shr $__ASM_SEL(2, 3), %_ASM_CX
rep __ASM_SIZE(stos)
- mov %_ASM_SI, xen_start_info
- mov $init_thread_union+THREAD_SIZE, %_ASM_SP
+ _ASM_GET_PTR(xen_start_info, %_ASM_AX)
+ mov %_ASM_SI, (%_ASM_AX)
+ _ASM_GET_PTR(init_thread_union+THREAD_SIZE, %_ASM_SP)
jmp xen_start_kernel
--
2.13.2.932.g7449e964c-goog
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
