[GIT pull] x86 fixes for 4.14

From: Thomas Gleixner
Date: Sun Nov 12 2017 - 07:00:22 EST


Linus,

please pull the latest x86-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-urgent-for-linus

A set of small fixes:

- Make KGDB work again which got broken by the conversion of WARN() to
#UD. The WARN fixup needs to run before the notifier callchain, otherwise
KGDB tries to handle it and crashes.

- Disable KASAN in the ORC unwinder to prevent false positive KASAN warnings

- Prevent default mapping above 47bit when 5 level page tables are enabled

- Make the delay calibration optimization work correctly, which had the
conditionals the wrong way around and was operating on data which was
not yet updated.

- Remove the bogus X86_TRAP_BP trap init from the default IDT init table,
which broke 32bit int3 handling by overwriting the correct int3 setup.

- Replace this_cpu* with boot_cpu_data access in the preemptible oprofile
init code.

Thanks,

tglx

------------------>
Alexander Shishkin (1):
x86/debug: Handle warnings before the notifier chain, to fix KGDB crash

Borislav Petkov (1):
x86/oprofile/ppro: Do not use __this_cpu*() in preemptible context

Josh Poimboeuf (1):
x86/unwind: Disable KASAN checking in the ORC unwinder

Kirill A. Shutemov (1):
x86/mm: Fix ELF_ET_DYN_BASE for 5-level paging

Pavel Tatashin (1):
x86/smpboot: Make optimization of delay calibration work correctly

Yonghong Song (1):
x86/idt: Remove X86_TRAP_BP initialization in idt_setup_traps()


arch/x86/include/asm/elf.h | 2 +-
arch/x86/kernel/idt.c | 2 --
arch/x86/kernel/smpboot.c | 11 ++++++-----
arch/x86/kernel/traps.c | 10 +++++++---
arch/x86/kernel/tsc.c | 8 +++-----
arch/x86/kernel/unwind_orc.c | 2 +-
arch/x86/oprofile/op_model_ppro.c | 4 ++--
7 files changed, 20 insertions(+), 19 deletions(-)

diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h
index c1a125e47ff3..3a091cea36c5 100644
--- a/arch/x86/include/asm/elf.h
+++ b/arch/x86/include/asm/elf.h
@@ -253,7 +253,7 @@ extern int force_personality32;
* space open for things that want to use the area for 32-bit pointers.
*/
#define ELF_ET_DYN_BASE (mmap_is_ia32() ? 0x000400000UL : \
- (TASK_SIZE / 3 * 2))
+ (DEFAULT_MAP_WINDOW / 3 * 2))

/* This yields a mask that user programs can use to figure out what
instruction set this CPU supports. This could be done in user space,
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 6107ee1cb8d5..014cb2fc47ff 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -92,8 +92,6 @@ static const __initdata struct idt_data def_idts[] = {
INTG(X86_TRAP_DF, double_fault),
#endif
INTG(X86_TRAP_DB, debug),
- INTG(X86_TRAP_NMI, nmi),
- INTG(X86_TRAP_BP, int3),

#ifdef CONFIG_X86_MCE
INTG(X86_TRAP_MC, &machine_check),
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index ad59edd84de7..65a0ccdc3050 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -194,6 +194,12 @@ static void smp_callin(void)
smp_store_cpu_info(cpuid);

/*
+ * The topology information must be up to date before
+ * calibrate_delay() and notify_cpu_starting().
+ */
+ set_cpu_sibling_map(raw_smp_processor_id());
+
+ /*
* Get our bogomips.
* Update loops_per_jiffy in cpu_data. Previous call to
* smp_store_cpu_info() stored a value that is close but not as
@@ -203,11 +209,6 @@ static void smp_callin(void)
cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy;
pr_debug("Stack at about %p\n", &cpuid);

- /*
- * This must be done before setting cpu_online_mask
- * or calling notify_cpu_starting.
- */
- set_cpu_sibling_map(raw_smp_processor_id());
wmb();

notify_cpu_starting(cpuid);
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 67db4f43309e..5a6b8f809792 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -209,9 +209,6 @@ do_trap_no_signal(struct task_struct *tsk, int trapnr, char *str,
if (fixup_exception(regs, trapnr))
return 0;

- if (fixup_bug(regs, trapnr))
- return 0;
-
tsk->thread.error_code = error_code;
tsk->thread.trap_nr = trapnr;
die(str, regs, error_code);
@@ -292,6 +289,13 @@ static void do_error_trap(struct pt_regs *regs, long error_code, char *str,

RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");

+ /*
+ * WARN*()s end up here; fix them up before we call the
+ * notifier chain.
+ */
+ if (!user_mode(regs) && fixup_bug(regs, trapnr))
+ return;
+
if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) !=
NOTIFY_STOP) {
cond_local_irq_enable(regs);
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 796d96bb0821..ad2b925a808e 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -1346,12 +1346,10 @@ void __init tsc_init(void)
unsigned long calibrate_delay_is_known(void)
{
int sibling, cpu = smp_processor_id();
- struct cpumask *mask = topology_core_cpumask(cpu);
+ int constant_tsc = cpu_has(&cpu_data(cpu), X86_FEATURE_CONSTANT_TSC);
+ const struct cpumask *mask = topology_core_cpumask(cpu);

- if (!tsc_disabled && !cpu_has(&cpu_data(cpu), X86_FEATURE_CONSTANT_TSC))
- return 0;
-
- if (!mask)
+ if (tsc_disabled || !constant_tsc || !mask)
return 0;

sibling = cpumask_any_but(mask, cpu);
diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
index b95007e7c1b3..a3f973b2c97a 100644
--- a/arch/x86/kernel/unwind_orc.c
+++ b/arch/x86/kernel/unwind_orc.c
@@ -279,7 +279,7 @@ static bool deref_stack_reg(struct unwind_state *state, unsigned long addr,
if (!stack_access_ok(state, addr, sizeof(long)))
return false;

- *val = READ_ONCE_TASK_STACK(state->task, *(unsigned long *)addr);
+ *val = READ_ONCE_NOCHECK(*(unsigned long *)addr);
return true;
}

diff --git a/arch/x86/oprofile/op_model_ppro.c b/arch/x86/oprofile/op_model_ppro.c
index 350f7096baac..7913b6921959 100644
--- a/arch/x86/oprofile/op_model_ppro.c
+++ b/arch/x86/oprofile/op_model_ppro.c
@@ -212,8 +212,8 @@ static void arch_perfmon_setup_counters(void)
eax.full = cpuid_eax(0xa);

/* Workaround for BIOS bugs in 6/15. Taken from perfmon2 */
- if (eax.split.version_id == 0 && __this_cpu_read(cpu_info.x86) == 6 &&
- __this_cpu_read(cpu_info.x86_model) == 15) {
+ if (eax.split.version_id == 0 && boot_cpu_data.x86 == 6 &&
+ boot_cpu_data.x86_model == 15) {
eax.split.version_id = 2;
eax.split.num_counters = 2;
eax.split.bit_width = 40;