Re: [Xen-devel] Re: [PATCH 00 of 36] x86/paravirt: groundwork for 64-bit Xen support

Jeremy Fitzhardinge
2008-06-27T19:04:19Z

Ingo Molnar wrote:
> this problem still reproduces.
>
> i've pushed out all fixes into tip/x86/xen-64bit. That branch combined
> with the config above still reproduces the build failure above.
>

Subject: x86_64: fix non-paravirt compilation

Make sure SWAPGS and PARAVIRT_ADJUST_EXCEPTION_FRAME are properly
defined when CONFIG_PARAVIRT is off.

Fixes Ingo's build failure:
arch/x86/kernel/entry_64.S: Assembler messages:
arch/x86/kernel/entry_64.S:1201: Error: invalid character '_' in mnemonic
arch/x86/kernel/entry_64.S:1205: Error: invalid character '_' in mnemonic
arch/x86/kernel/entry_64.S:1209: Error: invalid character '_' in mnemonic
arch/x86/kernel/entry_64.S:1213: Error: invalid character '_' in mnemonic

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
---
include/asm-x86/irqflags.h | 22 +++++++++++++---------
include/asm-x86/processor.h | 3 ---
2 files changed, 13 insertions(+), 12 deletions(-)

===================================================================
--- a/include/asm-x86/irqflags.h
+++ b/include/asm-x86/irqflags.h
@@ -167,7 +167,20 @@
#define INTERRUPT_RETURN_NMI_SAFE NATIVE_INTERRUPT_RETURN_NMI_SAFE

#ifdef CONFIG_X86_64
+#define SWAPGS swapgs
+/*
+ * Currently paravirt can't handle swapgs nicely when we
+ * don't have a stack we can rely on (such as a user space
+ * stack). So we either find a way around these or just fault
+ * and emulate if a guest tries to call swapgs directly.
+ *
+ * Either way, this is a good way to document that we don't
+ * have a reliable stack. x86_64 only.
+ */
#define SWAPGS_UNSAFE_STACK swapgs
+
+#define PARAVIRT_ADJUST_EXCEPTION_FRAME /* */
+
#define INTERRUPT_RETURN iretq
#define USERGS_SYSRET64 \
swapgs; \
@@ -233,15 +246,6 @@
#else

#ifdef CONFIG_X86_64
-/*
- * Currently paravirt can't handle swapgs nicely when we
- * don't have a stack we can rely on (such as a user space
- * stack). So we either find a way around these or just fault
- * and emulate if a guest tries to call swapgs directly.
- *
- * Either way, this is a good way to document that we don't
- * have a reliable stack. x86_64 only.
- */
#define ARCH_LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk
#define ARCH_LOCKDEP_SYS_EXIT_IRQ \
TRACE_IRQS_ON; \
===================================================================
--- a/include/asm-x86/processor.h
+++ b/include/asm-x86/processor.h
@@ -541,9 +541,6 @@
}

#define set_iopl_mask native_set_iopl_mask
-#define SWAPGS swapgs
-
-#define PARAVIRT_ADJUST_EXCEPTION_FRAME /* */
#endif /* CONFIG_PARAVIRT */

/*