From 72f5e08dbba2d01aa90b592cf76c378ea233b00b Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Mon, 4 Dec 2017 15:07:20 +0100 Subject: x86/entry: Remap the TSS into the CPU entry area This has a secondary purpose: it puts the entry stack into a region with a well-controlled layout. A subsequent patch will take advantage of this to streamline the SYSCALL entry code to be able to find it more easily. Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Reviewed-by: Thomas Gleixner Reviewed-by: Borislav Petkov Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Dave Hansen Cc: David Laight Cc: Denys Vlasenko Cc: Eduardo Valentin Cc: Greg KH Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: Will Deacon Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Link: https://lkml.kernel.org/r/20171204150605.962042855@linutronix.de Signed-off-by: Ingo Molnar --- arch/x86/kernel/dumpstack.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/x86/kernel/dumpstack.c') diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c index 64f8ed2a4827..60267850125e 100644 --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -45,7 +45,8 @@ bool in_task_stack(unsigned long *stack, struct task_struct *task, bool in_sysenter_stack(unsigned long *stack, struct stack_info *info) { - struct tss_struct *tss = this_cpu_ptr(&cpu_tss); + int cpu = smp_processor_id(); + struct tss_struct *tss = &get_cpu_entry_area(cpu)->tss; /* Treat the canary as part of the stack for unwinding purposes. */ void *begin = &tss->SYSENTER_stack_canary; -- cgit v1.2.3