x86/entry/64: Separate cpu_current_top_of_stack from TSS.sp0
authorAndy Lutomirski <luto@kernel.org>
Mon, 4 Dec 2017 14:07:21 +0000 (15:07 +0100)
committerIngo Molnar <mingo@kernel.org>
Sun, 17 Dec 2017 12:59:56 +0000 (13:59 +0100)
commit9aaefe7b59ae00605256a7d6bd1c1456432495fc
treed1b102114ade2f18511d6d9dbd9345cbc4891a3b
parent72f5e08dbba2d01aa90b592cf76c378ea233b00b
x86/entry/64: Separate cpu_current_top_of_stack from TSS.sp0

On 64-bit kernels, we used to assume that TSS.sp0 was the current
top of stack.  With the addition of an entry trampoline, this will
no longer be the case.  Store the current top of stack in TSS.sp1,
which is otherwise unused but shares the same cacheline.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.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: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
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
Link: https://lkml.kernel.org/r/20171204150606.050864668@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/include/asm/processor.h
arch/x86/include/asm/thread_info.h
arch/x86/kernel/asm-offsets_64.c
arch/x86/kernel/process.c
arch/x86/kernel/process_64.c