diff options
| author | Andy Lutomirski <luto@kernel.org> | 2017-12-04 17:07:20 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-12-17 15:59:56 +0300 |
| commit | 72f5e08dbba2d01aa90b592cf76c378ea233b00b (patch) | |
| tree | 6289081b74696a9562d06b50e823d6ef1430f66b /arch/x86/power | |
| parent | 1a935bc3d4ea61556461a9e92a68ca3556232efd (diff) | |
| download | linux-72f5e08dbba2d01aa90b592cf76c378ea233b00b.tar.xz | |
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 <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bpetkov@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.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/20171204150605.962042855@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/power')
| -rw-r--r-- | arch/x86/power/cpu.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c index 50593e138281..04d5157fe7f8 100644 --- a/arch/x86/power/cpu.c +++ b/arch/x86/power/cpu.c @@ -160,18 +160,19 @@ static void do_fpu_end(void) static void fix_processor_context(void) { int cpu = smp_processor_id(); - struct tss_struct *t = &per_cpu(cpu_tss, cpu); #ifdef CONFIG_X86_64 struct desc_struct *desc = get_cpu_gdt_rw(cpu); tss_desc tss; #endif /* - * This just modifies memory; should not be necessary. But... This is - * necessary, because 386 hardware has concept of busy TSS or some - * similar stupidity. + * We need to reload TR, which requires that we change the + * GDT entry to indicate "available" first. + * + * XXX: This could probably all be replaced by a call to + * force_reload_TR(). */ - set_tss_desc(cpu, &t->x86_tss); + set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss); #ifdef CONFIG_X86_64 memcpy(&tss, &desc[GDT_ENTRY_TSS], sizeof(tss_desc)); |