Merge branch 'kvm-ppc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into next
Two bug fixes for HV KVM on POWER9 machines.
diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
index cb8f914..1548ca9 100644
--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -205,6 +205,8 @@
asm volatile("ltr %w0"::"q" (GDT_ENTRY_TSS*8));
}
+DECLARE_PER_CPU(bool, __tss_limit_invalid);
+
static inline void force_reload_TR(void)
{
struct desc_struct *d = get_cpu_gdt_table(smp_processor_id());
@@ -220,18 +222,20 @@
write_gdt_entry(d, GDT_ENTRY_TSS, &tss, DESC_TSS);
load_TR_desc();
+ this_cpu_write(__tss_limit_invalid, false);
}
-DECLARE_PER_CPU(bool, need_tr_refresh);
-
-static inline void refresh_TR(void)
+/*
+ * Call this if you need the TSS limit to be correct, which should be the case
+ * if and only if you have TIF_IO_BITMAP set or you're switching to a task
+ * with TIF_IO_BITMAP set.
+ */
+static inline void refresh_tss_limit(void)
{
DEBUG_LOCKS_WARN_ON(preemptible());
- if (unlikely(this_cpu_read(need_tr_refresh))) {
+ if (unlikely(this_cpu_read(__tss_limit_invalid)))
force_reload_TR();
- this_cpu_write(need_tr_refresh, false);
- }
}
/*
@@ -250,7 +254,7 @@
if (unlikely(test_thread_flag(TIF_IO_BITMAP)))
force_reload_TR();
else
- this_cpu_write(need_tr_refresh, true);
+ this_cpu_write(__tss_limit_invalid, true);
}
static inline void native_load_gdt(const struct desc_ptr *dtr)
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 @@
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 @@
};
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 @@
* 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:
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index 06ce377d..026db42 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -113,12 +113,19 @@
.config = config,
};
+ attr.sample_period = (-pmc->counter) & pmc_bitmask(pmc);
+
if (in_tx)
attr.config |= HSW_IN_TX;
- if (in_tx_cp)
+ if (in_tx_cp) {
+ /*
+ * HSW_IN_TX_CHECKPOINTED is not supported with nonzero
+ * period. Just clear the sample period so at least
+ * allocating the counter doesn't fail.
+ */
+ attr.sample_period = 0;
attr.config |= HSW_IN_TX_CHECKPOINTED;
-
- attr.sample_period = (-pmc->counter) & pmc_bitmask(pmc);
+ }
event = perf_event_create_kernel_counter(&attr, -1, current,
intr ? kvm_perf_overflow_intr :
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index ef4ba71..283aa86 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2053,7 +2053,6 @@
static unsigned long segment_base(u16 selector)
{
struct desc_ptr *gdt = this_cpu_ptr(&host_gdt);
- struct desc_struct *d;
struct desc_struct *table;
unsigned long v;
@@ -10642,6 +10641,11 @@
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
+ if (vcpu->arch.exception.pending ||
+ vcpu->arch.nmi_injected ||
+ vcpu->arch.interrupt.pending)
+ return -EBUSY;
+
if (nested_cpu_has_preemption_timer(get_vmcs12(vcpu)) &&
vmx->nested.preemption_timer_expired) {
if (vmx->nested.nested_run_pending)
@@ -10651,8 +10655,7 @@
}
if (vcpu->arch.nmi_pending && nested_exit_on_nmi(vcpu)) {
- if (vmx->nested.nested_run_pending ||
- vcpu->arch.interrupt.pending)
+ if (vmx->nested.nested_run_pending)
return -EBUSY;
nested_vmx_vmexit(vcpu, EXIT_REASON_EXCEPTION_NMI,
NMI_VECTOR | INTR_TYPE_NMI_INTR |
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 8d69d51..2c14ad9 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -26,6 +26,7 @@
#include <linux/context_tracking.h>
#include <linux/irqbypass.h>
#include <linux/swait.h>
+#include <linux/refcount.h>
#include <asm/signal.h>
#include <linux/kvm.h>
@@ -401,7 +402,7 @@
#endif
struct kvm_vm_stat stat;
struct kvm_arch arch;
- atomic_t users_count;
+ refcount_t users_count;
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
spinlock_t ring_lock;
diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile
index 83d8b1c..bed3e608 100644
--- a/tools/testing/selftests/x86/Makefile
+++ b/tools/testing/selftests/x86/Makefile
@@ -5,7 +5,7 @@
.PHONY: all all_32 all_64 warn_32bit_failure clean
TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt ptrace_syscall test_mremap_vdso \
- check_initial_reg_state sigreturn ldt_gdt iopl mpx-mini-test \
+ check_initial_reg_state sigreturn ldt_gdt iopl mpx-mini-test ioperm \
protection_keys test_vdso
TARGETS_C_32BIT_ONLY := entry_from_vm86 syscall_arg_fault test_syscall_vdso unwind_vdso \
test_FCMOV test_FCOMI test_FISTTP \
diff --git a/tools/testing/selftests/x86/ioperm.c b/tools/testing/selftests/x86/ioperm.c
new file mode 100644
index 0000000..b77313b
--- /dev/null
+++ b/tools/testing/selftests/x86/ioperm.c
@@ -0,0 +1,170 @@
+/*
+ * ioperm.c - Test case for ioperm(2)
+ * Copyright (c) 2015 Andrew Lutomirski
+ */
+
+#define _GNU_SOURCE
+#include <err.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <signal.h>
+#include <setjmp.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <stdbool.h>
+#include <sched.h>
+#include <sys/io.h>
+
+static int nerrs = 0;
+
+static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *),
+ int flags)
+{
+ struct sigaction sa;
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_sigaction = handler;
+ sa.sa_flags = SA_SIGINFO | flags;
+ sigemptyset(&sa.sa_mask);
+ if (sigaction(sig, &sa, 0))
+ err(1, "sigaction");
+
+}
+
+static void clearhandler(int sig)
+{
+ struct sigaction sa;
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_handler = SIG_DFL;
+ sigemptyset(&sa.sa_mask);
+ if (sigaction(sig, &sa, 0))
+ err(1, "sigaction");
+}
+
+static jmp_buf jmpbuf;
+
+static void sigsegv(int sig, siginfo_t *si, void *ctx_void)
+{
+ siglongjmp(jmpbuf, 1);
+}
+
+static bool try_outb(unsigned short port)
+{
+ sethandler(SIGSEGV, sigsegv, SA_RESETHAND);
+ if (sigsetjmp(jmpbuf, 1) != 0) {
+ return false;
+ } else {
+ asm volatile ("outb %%al, %w[port]"
+ : : [port] "Nd" (port), "a" (0));
+ return true;
+ }
+ clearhandler(SIGSEGV);
+}
+
+static void expect_ok(unsigned short port)
+{
+ if (!try_outb(port)) {
+ printf("[FAIL]\toutb to 0x%02hx failed\n", port);
+ exit(1);
+ }
+
+ printf("[OK]\toutb to 0x%02hx worked\n", port);
+}
+
+static void expect_gp(unsigned short port)
+{
+ if (try_outb(port)) {
+ printf("[FAIL]\toutb to 0x%02hx worked\n", port);
+ exit(1);
+ }
+
+ printf("[OK]\toutb to 0x%02hx failed\n", port);
+}
+
+int main(void)
+{
+ cpu_set_t cpuset;
+ CPU_ZERO(&cpuset);
+ CPU_SET(0, &cpuset);
+ if (sched_setaffinity(0, sizeof(cpuset), &cpuset) != 0)
+ err(1, "sched_setaffinity to CPU 0");
+
+ expect_gp(0x80);
+ expect_gp(0xed);
+
+ /*
+ * Probe for ioperm support. Note that clearing ioperm bits
+ * works even as nonroot.
+ */
+ printf("[RUN]\tenable 0x80\n");
+ if (ioperm(0x80, 1, 1) != 0) {
+ printf("[OK]\tioperm(0x80, 1, 1) failed (%d) -- try running as root\n",
+ errno);
+ return 0;
+ }
+ expect_ok(0x80);
+ expect_gp(0xed);
+
+ printf("[RUN]\tdisable 0x80\n");
+ if (ioperm(0x80, 1, 0) != 0) {
+ printf("[FAIL]\tioperm(0x80, 1, 0) failed (%d)", errno);
+ return 1;
+ }
+ expect_gp(0x80);
+ expect_gp(0xed);
+
+ /* Make sure that fork() preserves ioperm. */
+ if (ioperm(0x80, 1, 1) != 0) {
+ printf("[FAIL]\tioperm(0x80, 1, 0) failed (%d)", errno);
+ return 1;
+ }
+
+ pid_t child = fork();
+ if (child == -1)
+ err(1, "fork");
+
+ if (child == 0) {
+ printf("[RUN]\tchild: check that we inherited permissions\n");
+ expect_ok(0x80);
+ expect_gp(0xed);
+ return 0;
+ } else {
+ int status;
+ if (waitpid(child, &status, 0) != child ||
+ !WIFEXITED(status)) {
+ printf("[FAIL]\tChild died\n");
+ nerrs++;
+ } else if (WEXITSTATUS(status) != 0) {
+ printf("[FAIL]\tChild failed\n");
+ nerrs++;
+ } else {
+ printf("[OK]\tChild succeeded\n");
+ }
+ }
+
+ /* Test the capability checks. */
+
+ printf("\tDrop privileges\n");
+ if (setresuid(1, 1, 1) != 0) {
+ printf("[WARN]\tDropping privileges failed\n");
+ return 0;
+ }
+
+ printf("[RUN]\tdisable 0x80\n");
+ if (ioperm(0x80, 1, 0) != 0) {
+ printf("[FAIL]\tioperm(0x80, 1, 0) failed (%d)", errno);
+ return 1;
+ }
+ printf("[OK]\tit worked\n");
+
+ printf("[RUN]\tenable 0x80 again\n");
+ if (ioperm(0x80, 1, 1) == 0) {
+ printf("[FAIL]\tit succeeded but should have failed.\n");
+ return 1;
+ }
+ printf("[OK]\tit failed\n");
+ return 0;
+}
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index cc4d6e0..c6b7aff 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -617,7 +617,7 @@
mutex_init(&kvm->lock);
mutex_init(&kvm->irq_lock);
mutex_init(&kvm->slots_lock);
- atomic_set(&kvm->users_count, 1);
+ refcount_set(&kvm->users_count, 1);
INIT_LIST_HEAD(&kvm->devices);
r = kvm_arch_init_vm(kvm, type);
@@ -747,13 +747,13 @@
void kvm_get_kvm(struct kvm *kvm)
{
- atomic_inc(&kvm->users_count);
+ refcount_inc(&kvm->users_count);
}
EXPORT_SYMBOL_GPL(kvm_get_kvm);
void kvm_put_kvm(struct kvm *kvm)
{
- if (atomic_dec_and_test(&kvm->users_count))
+ if (refcount_dec_and_test(&kvm->users_count))
kvm_destroy_vm(kvm);
}
EXPORT_SYMBOL_GPL(kvm_put_kvm);
@@ -3639,7 +3639,7 @@
* To avoid the race between open and the removal of the debugfs
* directory we test against the users count.
*/
- if (!atomic_add_unless(&stat_data->kvm->users_count, 1, 0))
+ if (!refcount_inc_not_zero(&stat_data->kvm->users_count))
return -ENOENT;
if (simple_attr_open(inode, file, get, set, fmt)) {
