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-rw-r--r--arch/x86/kernel/acpi/boot.c20
-rw-r--r--arch/x86/kernel/acpi/sleep.c23
2 files changed, 33 insertions, 10 deletions
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 1c38174b5f01..21b542a6866c 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -146,7 +146,11 @@ static int __init acpi_parse_madt(struct acpi_table_header *table)
pr_debug("Local APIC address 0x%08x\n", madt->address);
}
- if (madt->header.revision >= 5)
+
+ /* ACPI 6.3 and newer support the online capable bit. */
+ if (acpi_gbl_FADT.header.revision > 6 ||
+ (acpi_gbl_FADT.header.revision == 6 &&
+ acpi_gbl_FADT.minor_revision >= 3))
acpi_support_online_capable = true;
default_acpi_madt_oem_check(madt->header.oem_id,
@@ -193,7 +197,8 @@ static bool __init acpi_is_processor_usable(u32 lapic_flags)
if (lapic_flags & ACPI_MADT_ENABLED)
return true;
- if (acpi_support_online_capable && (lapic_flags & ACPI_MADT_ONLINE_CAPABLE))
+ if (!acpi_support_online_capable ||
+ (lapic_flags & ACPI_MADT_ONLINE_CAPABLE))
return true;
return false;
@@ -1853,13 +1858,18 @@ early_param("acpi_sci", setup_acpi_sci);
int __acpi_acquire_global_lock(unsigned int *lock)
{
- unsigned int old, new;
+ unsigned int old, new, val;
old = READ_ONCE(*lock);
do {
- new = (((old & ~0x3) + 2) + ((old >> 1) & 0x1));
+ val = (old >> 1) & 0x1;
+ new = (old & ~0x3) + 2 + val;
} while (!try_cmpxchg(lock, &old, new));
- return ((new & 0x3) < 3) ? -1 : 0;
+
+ if (val)
+ return 0;
+
+ return -1;
}
int __acpi_release_global_lock(unsigned int *lock)
diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
index 3b7f4cdbf2e0..1328c221af30 100644
--- a/arch/x86/kernel/acpi/sleep.c
+++ b/arch/x86/kernel/acpi/sleep.c
@@ -111,13 +111,26 @@ int x86_acpi_suspend_lowlevel(void)
saved_magic = 0x12345678;
#else /* CONFIG_64BIT */
#ifdef CONFIG_SMP
- initial_stack = (unsigned long)temp_stack + sizeof(temp_stack);
- early_gdt_descr.address =
- (unsigned long)get_cpu_gdt_rw(smp_processor_id());
- initial_gs = per_cpu_offset(smp_processor_id());
+ /*
+ * As each CPU starts up, it will find its own stack pointer
+ * from its current_task->thread.sp. Typically that will be
+ * the idle thread for a newly-started AP, or even the boot
+ * CPU which will find it set to &init_task in the static
+ * per-cpu data.
+ *
+ * Make the resuming CPU use the temporary stack at startup
+ * by setting current->thread.sp to point to that. The true
+ * %rsp will be restored with the rest of the CPU context,
+ * by do_suspend_lowlevel(). And unwinders don't care about
+ * the abuse of ->thread.sp because it's a dead variable
+ * while the thread is running on the CPU anyway; the true
+ * value is in the actual %rsp register.
+ */
+ current->thread.sp = (unsigned long)temp_stack + sizeof(temp_stack);
+ smpboot_control = smp_processor_id();
#endif
initial_code = (unsigned long)wakeup_long64;
- saved_magic = 0x123456789abcdef0L;
+ saved_magic = 0x123456789abcdef0L;
#endif /* CONFIG_64BIT */
/*