diff options
| author | Jeremy Fitzhardinge <jeremy@goop.org> | 2008-06-25 08:19:28 +0400 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-07-08 15:15:52 +0400 |
| commit | 2be29982a08009c731307f4a39053b70ac4700da (patch) | |
| tree | f01fcf847f36b9da5cd87cefa7ee6c13d193077d /arch/x86/ia32 | |
| parent | c7245da6ae7e5208504ff027c4e0eec69b788651 (diff) | |
| download | linux-2be29982a08009c731307f4a39053b70ac4700da.tar.xz | |
x86/paravirt: add sysret/sysexit pvops for returning to 32-bit compatibility userspace
In a 64-bit system, we need separate sysret/sysexit operations to
return to a 32-bit userspace.
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/ia32')
| -rw-r--r-- | arch/x86/ia32/ia32entry.S | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S index 3aefbce2de48..2a4c42427d9a 100644 --- a/arch/x86/ia32/ia32entry.S +++ b/arch/x86/ia32/ia32entry.S @@ -61,6 +61,19 @@ CFI_UNDEFINED r15 .endm +#ifdef CONFIG_PARAVIRT +ENTRY(native_usergs_sysret32) + swapgs + sysretl +ENDPROC(native_usergs_sysret32) + +ENTRY(native_irq_enable_sysexit) + swapgs + sti + sysexit +ENDPROC(native_irq_enable_sysexit) +#endif + /* * 32bit SYSENTER instruction entry. * @@ -151,10 +164,7 @@ sysenter_do_call: CFI_ADJUST_CFA_OFFSET -8 CFI_REGISTER rsp,rcx TRACE_IRQS_ON - swapgs - sti /* sti only takes effect after the next instruction */ - /* sysexit */ - .byte 0xf, 0x35 + ENABLE_INTERRUPTS_SYSEXIT32 sysenter_tracesys: CFI_RESTORE_STATE @@ -254,8 +264,7 @@ cstar_do_call: TRACE_IRQS_ON movl RSP-ARGOFFSET(%rsp),%esp CFI_RESTORE rsp - swapgs - sysretl + USERGS_SYSRET32 cstar_tracesys: CFI_RESTORE_STATE |