x86/entry/32: Rename TSS_sysenter_sp0 to TSS_entry2task_stack

The stack address doesn't need to be stored in tss.sp0 if the stack is
switched manually like on sysenter. Rename the offset so that it still
makes sense when its location is changed in later patches.

This stackk will also be used for all kernel-entry points, not just
sysenter. Reflect that and the fact that it is the offset to the task-stack
location in the name as well.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-3-git-send-email-joro@8bytes.org

diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index c371bfe..39f711a 100644 (file)
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -412,7 +412,7 @@ ENTRY(xen_sysenter_target)
  * 0(%ebp) arg6
  */
 ENTRY(entry_SYSENTER_32)
-       movl    TSS_sysenter_sp0(%esp), %esp
+       movl    TSS_entry2task_stack(%esp), %esp
 .Lsysenter_past_esp:
        pushl   $__USER_DS              /* pt_regs->ss */
        pushl   %ebp                    /* pt_regs->sp (stashed in bp) */

diff --git a/arch/x86/kernel/asm-offsets_32.c b/arch/x86/kernel/asm-offsets_32.c
index a4a3be3..15b3f45 100644 (file)
--- a/arch/x86/kernel/asm-offsets_32.c
+++ b/arch/x86/kernel/asm-offsets_32.c
@@ -46,8 +46,9 @@ void foo(void)
        OFFSET(saved_context_gdt_desc, saved_context, gdt_desc);
        BLANK();
 
-       /* Offset from the sysenter stack to tss.sp0 */
-       DEFINE(TSS_sysenter_sp0, offsetof(struct cpu_entry_area, tss.x86_tss.sp0) -
+       /* Offset from the entry stack to task stack stored in TSS */
+       DEFINE(TSS_entry2task_stack,
+              offsetof(struct cpu_entry_area, tss.x86_tss.sp0) -
               offsetofend(struct cpu_entry_area, entry_stack_page.stack));
 
 #ifdef CONFIG_STACKPROTECTOR