aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJosh Poimboeuf <jpoimboe@redhat.com>2016-01-21 16:49:09 -0600
committerIngo Molnar <mingo@kernel.org>2016-02-24 08:35:41 +0100
commit0e8e2238b52e5301d1d1d4a298ec5b72ac54c702 (patch)
tree746e51ce70ec89bf7262db41ad58e3340678298b
parent0f68c088c0adb3c3bbeb487c4ebcde91fd5d34be (diff)
x86/xen: Add stack frame dependency to hypercall inline asm calls
If a hypercall is inlined at the beginning of a function, gcc can insert the call instruction before setting up a stack frame, which breaks frame pointer convention if CONFIG_FRAME_POINTER is enabled and can result in a bad stack trace. Force a stack frame to be created if CONFIG_FRAME_POINTER is enabled by listing the stack pointer as an output operand for the hypercall inline asm statements. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chris J Arges <chris.j.arges@canonical.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Pedro Alves <palves@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/c6face5a46713108bded9c4c103637222abc4528.1453405861.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
-rw-r--r--arch/x86/include/asm/xen/hypercall.h5
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h
index 3bcdcc84259d..a12a047184ee 100644
--- a/arch/x86/include/asm/xen/hypercall.h
+++ b/arch/x86/include/asm/xen/hypercall.h
@@ -110,9 +110,10 @@ extern struct { char _entry[32]; } hypercall_page[];
register unsigned long __arg2 asm(__HYPERCALL_ARG2REG) = __arg2; \
register unsigned long __arg3 asm(__HYPERCALL_ARG3REG) = __arg3; \
register unsigned long __arg4 asm(__HYPERCALL_ARG4REG) = __arg4; \
- register unsigned long __arg5 asm(__HYPERCALL_ARG5REG) = __arg5;
+ register unsigned long __arg5 asm(__HYPERCALL_ARG5REG) = __arg5; \
+ register void *__sp asm(_ASM_SP);
-#define __HYPERCALL_0PARAM "=r" (__res)
+#define __HYPERCALL_0PARAM "=r" (__res), "+r" (__sp)
#define __HYPERCALL_1PARAM __HYPERCALL_0PARAM, "+r" (__arg1)
#define __HYPERCALL_2PARAM __HYPERCALL_1PARAM, "+r" (__arg2)
#define __HYPERCALL_3PARAM __HYPERCALL_2PARAM, "+r" (__arg3)