diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/traps.c | 20 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 5 | ||||
| -rw-r--r-- | arch/x86/xen/setup.c | 65 |
3 files changed, 41 insertions, 49 deletions
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index ade185a46b1d..679302c312f8 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -109,6 +109,12 @@ static inline void preempt_conditional_cli(struct pt_regs *regs) preempt_count_dec(); } +/* + * In IST context, we explicitly disable preemption. This serves two + * purposes: it makes it much less likely that we would accidentally + * schedule in IST context and it will force a warning if we somehow + * manage to schedule by accident. + */ void ist_enter(struct pt_regs *regs) { if (user_mode(regs)) { @@ -123,13 +129,7 @@ void ist_enter(struct pt_regs *regs) rcu_nmi_enter(); } - /* - * We are atomic because we're on the IST stack; or we're on - * x86_32, in which case we still shouldn't schedule; or we're - * on x86_64 and entered from user mode, in which case we're - * still atomic unless ist_begin_non_atomic is called. - */ - preempt_count_add(HARDIRQ_OFFSET); + preempt_disable(); /* This code is a bit fragile. Test it. */ RCU_LOCKDEP_WARN(!rcu_is_watching(), "ist_enter didn't work"); @@ -137,7 +137,7 @@ void ist_enter(struct pt_regs *regs) void ist_exit(struct pt_regs *regs) { - preempt_count_sub(HARDIRQ_OFFSET); + preempt_enable_no_resched(); if (!user_mode(regs)) rcu_nmi_exit(); @@ -168,7 +168,7 @@ void ist_begin_non_atomic(struct pt_regs *regs) BUG_ON((unsigned long)(current_top_of_stack() - current_stack_pointer()) >= THREAD_SIZE); - preempt_count_sub(HARDIRQ_OFFSET); + preempt_enable_no_resched(); } /** @@ -178,7 +178,7 @@ void ist_begin_non_atomic(struct pt_regs *regs) */ void ist_end_non_atomic(void) { - preempt_count_add(HARDIRQ_OFFSET); + preempt_disable(); } static nokprobe_inline int diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 605cea75eb0d..be222666b1c2 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3014,6 +3014,11 @@ static int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu, if (dbgregs->flags) return -EINVAL; + if (dbgregs->dr6 & ~0xffffffffull) + return -EINVAL; + if (dbgregs->dr7 & ~0xffffffffull) + return -EINVAL; + memcpy(vcpu->arch.db, dbgregs->db, sizeof(vcpu->arch.db)); kvm_update_dr0123(vcpu); vcpu->arch.dr6 = dbgregs->dr6; diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index 7ab29518a3b9..e345891450c3 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -393,6 +393,9 @@ static unsigned long __init xen_set_identity_and_remap_chunk( unsigned long i = 0; unsigned long n = end_pfn - start_pfn; + if (remap_pfn == 0) + remap_pfn = nr_pages; + while (i < n) { unsigned long cur_pfn = start_pfn + i; unsigned long left = n - i; @@ -438,17 +441,29 @@ static unsigned long __init xen_set_identity_and_remap_chunk( return remap_pfn; } -static void __init xen_set_identity_and_remap(unsigned long nr_pages) +static unsigned long __init xen_count_remap_pages( + unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages, + unsigned long remap_pages) +{ + if (start_pfn >= nr_pages) + return remap_pages; + + return remap_pages + min(end_pfn, nr_pages) - start_pfn; +} + +static unsigned long __init xen_foreach_remap_area(unsigned long nr_pages, + unsigned long (*func)(unsigned long start_pfn, unsigned long end_pfn, + unsigned long nr_pages, unsigned long last_val)) { phys_addr_t start = 0; - unsigned long last_pfn = nr_pages; + unsigned long ret_val = 0; const struct e820entry *entry = xen_e820_map; int i; /* * Combine non-RAM regions and gaps until a RAM region (or the - * end of the map) is reached, then set the 1:1 map and - * remap the memory in those non-RAM regions. + * end of the map) is reached, then call the provided function + * to perform its duty on the non-RAM region. * * The combined non-RAM regions are rounded to a whole number * of pages so any partial pages are accessible via the 1:1 @@ -466,14 +481,13 @@ static void __init xen_set_identity_and_remap(unsigned long nr_pages) end_pfn = PFN_UP(entry->addr); if (start_pfn < end_pfn) - last_pfn = xen_set_identity_and_remap_chunk( - start_pfn, end_pfn, nr_pages, - last_pfn); + ret_val = func(start_pfn, end_pfn, nr_pages, + ret_val); start = end; } } - pr_info("Released %ld page(s)\n", xen_released_pages); + return ret_val; } /* @@ -596,35 +610,6 @@ static void __init xen_ignore_unusable(void) } } -static unsigned long __init xen_count_remap_pages(unsigned long max_pfn) -{ - unsigned long extra = 0; - unsigned long start_pfn, end_pfn; - const struct e820entry *entry = xen_e820_map; - int i; - - end_pfn = 0; - for (i = 0; i < xen_e820_map_entries; i++, entry++) { - start_pfn = PFN_DOWN(entry->addr); - /* Adjacent regions on non-page boundaries handling! */ - end_pfn = min(end_pfn, start_pfn); - - if (start_pfn >= max_pfn) - return extra + max_pfn - end_pfn; - - /* Add any holes in map to result. */ - extra += start_pfn - end_pfn; - - end_pfn = PFN_UP(entry->addr + entry->size); - end_pfn = min(end_pfn, max_pfn); - - if (entry->type != E820_RAM) - extra += end_pfn - start_pfn; - } - - return extra; -} - bool __init xen_is_e820_reserved(phys_addr_t start, phys_addr_t size) { struct e820entry *entry; @@ -804,7 +789,7 @@ char * __init xen_memory_setup(void) max_pages = xen_get_max_pages(); /* How many extra pages do we need due to remapping? */ - max_pages += xen_count_remap_pages(max_pfn); + max_pages += xen_foreach_remap_area(max_pfn, xen_count_remap_pages); if (max_pages > max_pfn) extra_pages += max_pages - max_pfn; @@ -922,7 +907,9 @@ char * __init xen_memory_setup(void) * Set identity map on non-RAM pages and prepare remapping the * underlying RAM. */ - xen_set_identity_and_remap(max_pfn); + xen_foreach_remap_area(max_pfn, xen_set_identity_and_remap_chunk); + + pr_info("Released %ld page(s)\n", xen_released_pages); return "Xen"; } |