diff options
| author | Jeremy Fitzhardinge <jeremy@goop.org> | 2008-06-25 00:19:26 -0400 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-07-08 13:13:15 +0200 |
| commit | d75cd22fdd5f7d203fb60014d426942df33dd9a6 (patch) | |
| tree | 0613fca9d594eab9a0679f80510fa11b48b31571 /arch/x86/kernel/entry_64.S | |
| parent | e04e0a630d8b5c621b3a8e70ff20db737d3a5728 (diff) | |
x86/paravirt: split sysret and sysexit
Don't conflate sysret and sysexit; they're different instructions with
different semantics, and may be in use at the same time (at least
within the same kernel, depending on whether its an Intel or AMD
system).
sysexit - just return to userspace, does no register restoration of
any kind; must explicitly atomically enable interrupts.
sysret - reloads flags from r11, so no need to explicitly enable
interrupts on 64-bit, responsible for restoring usermode %gs
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citirx.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 'arch/x86/kernel/entry_64.S')
| -rw-r--r-- | arch/x86/kernel/entry_64.S | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 6d1101469e9..0056bc4c61a 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -59,7 +59,7 @@ #endif #ifdef CONFIG_PARAVIRT -ENTRY(native_irq_enable_syscall_ret) +ENTRY(native_usersp_sysret) movq %gs:pda_oldrsp,%rsp swapgs sysretq @@ -275,7 +275,7 @@ sysret_check: CFI_REGISTER rip,rcx RESTORE_ARGS 0,-ARG_SKIP,1 /*CFI_REGISTER rflags,r11*/ - ENABLE_INTERRUPTS_SYSCALL_RET + USERSP_SYSRET CFI_RESTORE_STATE /* Handle reschedules */ |