From b7ceaec112aa35aa287325754d8c52b8304892cd Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Wed, 22 Feb 2017 07:36:16 -0800 Subject: x86/asm: Tidy up TSS limit code MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In an earlier version of the patch ("x86/kvm/vmx: Defer TR reload after VM exit") that introduced TSS limit validity tracking, I confused which helper was which. On reflection, the names I chose sucked. Rename the helpers to make it more obvious what's going on and add some comments. While I'm at it, clear __tss_limit_invalid when force-reloading as well as when contitionally reloading, since any TR reload fixes the limit. Signed-off-by: Andy Lutomirski Signed-off-by: Radim Krčmář --- arch/x86/kernel/ioport.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'arch/x86/kernel/ioport.c') diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c index b01bc8517450..875d3d25dd6a 100644 --- a/arch/x86/kernel/ioport.c +++ b/arch/x86/kernel/ioport.c @@ -47,8 +47,14 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on) t->io_bitmap_ptr = bitmap; set_thread_flag(TIF_IO_BITMAP); + /* + * Now that we have an IO bitmap, we need our TSS limit to be + * correct. It's fine if we are preempted after doing this: + * with TIF_IO_BITMAP set, context switches will keep our TSS + * limit correct. + */ preempt_disable(); - refresh_TR(); + refresh_tss_limit(); preempt_enable(); } -- cgit v1.2.3