diff options
author | Jeremy Fitzhardinge <jeremy@goop.org> | 2008-06-25 00:19:30 -0400 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2008-07-08 07:15:56 -0400 |
commit | a00394f81f419beb6fb9f7023bd4d15913dc625d (patch) | |
tree | 0faef5a52c4244173a3669bc646ef12bb79d6bc6 /include/asm-x86/irqflags.h | |
parent | 6680415481c7bd38967cf7488787f509f17ba307 (diff) |
x86, 64-bit: swapgs pvop with a user-stack can never be called
It's never safe to call a swapgs pvop when the user stack is current -
it must be inline replaced. Rather than making a call, the
SWAPGS_UNSAFE_STACK pvop always just puts "swapgs" as a placeholder,
which must either be replaced inline or trap'n'emulated (somehow).
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include/asm-x86/irqflags.h')
-rw-r--r-- | include/asm-x86/irqflags.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/asm-x86/irqflags.h b/include/asm-x86/irqflags.h index ea9bd2635d59..d17e1f623dbb 100644 --- a/include/asm-x86/irqflags.h +++ b/include/asm-x86/irqflags.h | |||
@@ -111,6 +111,7 @@ static inline unsigned long __raw_local_irq_save(void) | |||
111 | #define DISABLE_INTERRUPTS(x) cli | 111 | #define DISABLE_INTERRUPTS(x) cli |
112 | 112 | ||
113 | #ifdef CONFIG_X86_64 | 113 | #ifdef CONFIG_X86_64 |
114 | #define SWAPGS_UNSAFE_STACK swapgs | ||
114 | #define INTERRUPT_RETURN iretq | 115 | #define INTERRUPT_RETURN iretq |
115 | #define USERGS_SYSRET64 \ | 116 | #define USERGS_SYSRET64 \ |
116 | swapgs; \ | 117 | swapgs; \ |
@@ -185,7 +186,6 @@ static inline void trace_hardirqs_fixup(void) | |||
185 | * Either way, this is a good way to document that we don't | 186 | * Either way, this is a good way to document that we don't |
186 | * have a reliable stack. x86_64 only. | 187 | * have a reliable stack. x86_64 only. |
187 | */ | 188 | */ |
188 | #define SWAPGS_UNSAFE_STACK swapgs | ||
189 | #define ARCH_TRACE_IRQS_ON call trace_hardirqs_on_thunk | 189 | #define ARCH_TRACE_IRQS_ON call trace_hardirqs_on_thunk |
190 | #define ARCH_TRACE_IRQS_OFF call trace_hardirqs_off_thunk | 190 | #define ARCH_TRACE_IRQS_OFF call trace_hardirqs_off_thunk |
191 | #define ARCH_LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk | 191 | #define ARCH_LOCKDEP_SYS_EXIT call lockdep_sys_exit_thunk |