x86, trampoline: Common infrastructure for low memory trampolines

Common infrastructure for low memory trampolines.  This code installs
the trampolines permanently in low memory very early.  It also permits
multiple pieces of code to be used for this purpose.

This code also introduces a standard infrastructure for computing
symbol addresses in the trampoline code.

The only change to the actual SMP trampolines themselves is that the
64-bit trampoline has been made reusable -- the previous version would
overwrite the code with a status variable; this moves the status
variable to a separate location.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <4D5DFBE4.7090104@intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Matthieu Castet <castet.matthieu@free.fr>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>

1 files changed, 0 insertions, 4 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index d5ed94d30aad..1359bc9f4fd3 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -217,10 +217,6 @@ config X86_HT
         def_bool y
         depends on SMP
 
-config X86_TRAMPOLINE
-        def_bool y
-        depends on SMP || (64BIT && ACPI_SLEEP)
-
 config X86_32_LAZY_GS
         def_bool y
         depends on X86_32 && !CC_STACKPROTECTOR