diff options
| author | Andy Lutomirski <luto@kernel.org> | 2017-02-22 07:36:16 -0800 |
|---|---|---|
| committer | Radim Krčmář <rkrcmar@redhat.com> | 2017-03-01 17:03:22 +0100 |
| commit | b7ceaec112aa35aa287325754d8c52b8304892cd (patch) | |
| tree | af5014f643adf8db9d82178bfb22f68062ed41c2 /arch/x86/kernel | |
| parent | e3736c3eb3a6f7c0966923b629c9f92b558aa9c7 (diff) | |
| download | op-kernel-dev-b7ceaec112aa35aa287325754d8c52b8304892cd.zip op-kernel-dev-b7ceaec112aa35aa287325754d8c52b8304892cd.tar.gz | |
x86/asm: Tidy up TSS limit code
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 <luto@kernel.org>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/ioport.c | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/process.c | 6 |
2 files changed, 10 insertions, 4 deletions
diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c index b01bc8517..875d3d2 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(); } diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 7780efa..0b30259 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -65,8 +65,8 @@ __visible DEFINE_PER_CPU_SHARED_ALIGNED(struct tss_struct, cpu_tss) = { }; EXPORT_PER_CPU_SYMBOL(cpu_tss); -DEFINE_PER_CPU(bool, need_tr_refresh); -EXPORT_PER_CPU_SYMBOL_GPL(need_tr_refresh); +DEFINE_PER_CPU(bool, __tss_limit_invalid); +EXPORT_PER_CPU_SYMBOL_GPL(__tss_limit_invalid); /* * this gets called so that we can store lazy state into memory and copy the @@ -218,7 +218,7 @@ void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p, * Make sure that the TSS limit is correct for the CPU * to notice the IO bitmap. */ - refresh_TR(); + refresh_tss_limit(); } else if (test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)) { /* * Clear any possible leftover bits: |
