Merge tag 'x86_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
- Ignore invalid x2APIC entries in order to not waste per-CPU data
- Fix a back-to-back signals handling scenario when shadow stack is in
use
- A documentation fix
- Add Kirill as TDX maintainer
* tag 'x86_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/acpi: Ignore invalid x2APIC entries
x86/shstk: Delay signal entry SSP write until after user accesses
x86/Documentation: Indent 'note::' directive for protocol version number note
MAINTAINERS: Add Intel TDX entry
diff --git a/Documentation/arch/x86/boot.rst b/Documentation/arch/x86/boot.rst
index f5d2f24..22cc7a0 100644
--- a/Documentation/arch/x86/boot.rst
+++ b/Documentation/arch/x86/boot.rst
@@ -77,7 +77,7 @@
Protocol 2.15 (Kernel 5.5) Added the kernel_info and kernel_info.setup_type_max.
============= ============================================================
-.. note::
+ .. note::
The protocol version number should be changed only if the setup header
is changed. There is no need to update the version number if boot_params
or kernel_info are changed. Additionally, it is recommended to use
diff --git a/MAINTAINERS b/MAINTAINERS
index 3e3206d..ea79014 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -23702,6 +23702,20 @@
F: arch/x86/kernel/stacktrace.c
F: arch/x86/kernel/unwind_*.c
+X86 TRUST DOMAIN EXTENSIONS (TDX)
+M: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
+R: Dave Hansen <dave.hansen@linux.intel.com>
+L: x86@kernel.org
+L: linux-coco@lists.linux.dev
+S: Supported
+T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/tdx
+F: arch/x86/boot/compressed/tdx*
+F: arch/x86/coco/tdx/
+F: arch/x86/include/asm/shared/tdx.h
+F: arch/x86/include/asm/tdx.h
+F: arch/x86/virt/vmx/tdx/
+F: drivers/virt/coco/tdx-guest
+
X86 VDSO
M: Andy Lutomirski <luto@kernel.org>
L: linux-kernel@vger.kernel.org
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index d0918a7..1a0dd80 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -63,6 +63,7 @@ int acpi_fix_pin2_polarity __initdata;
#ifdef CONFIG_X86_LOCAL_APIC
static u64 acpi_lapic_addr __initdata = APIC_DEFAULT_PHYS_BASE;
+static bool has_lapic_cpus __initdata;
static bool acpi_support_online_capable;
#endif
@@ -233,6 +234,14 @@ acpi_parse_x2apic(union acpi_subtable_headers *header, const unsigned long end)
return 0;
/*
+ * According to https://uefi.org/specs/ACPI/6.5/05_ACPI_Software_Programming_Model.html#processor-local-x2apic-structure
+ * when MADT provides both valid LAPIC and x2APIC entries, the APIC ID
+ * in x2APIC must be equal or greater than 0xff.
+ */
+ if (has_lapic_cpus && apic_id < 0xff)
+ return 0;
+
+ /*
* We need to register disabled CPU as well to permit
* counting disabled CPUs. This allows us to size
* cpus_possible_map more accurately, to permit
@@ -1114,10 +1123,7 @@ static int __init early_acpi_parse_madt_lapic_addr_ovr(void)
static int __init acpi_parse_madt_lapic_entries(void)
{
- int count;
- int x2count = 0;
- int ret;
- struct acpi_subtable_proc madt_proc[2];
+ int count, x2count = 0;
if (!boot_cpu_has(X86_FEATURE_APIC))
return -ENODEV;
@@ -1126,21 +1132,11 @@ static int __init acpi_parse_madt_lapic_entries(void)
acpi_parse_sapic, MAX_LOCAL_APIC);
if (!count) {
- memset(madt_proc, 0, sizeof(madt_proc));
- madt_proc[0].id = ACPI_MADT_TYPE_LOCAL_APIC;
- madt_proc[0].handler = acpi_parse_lapic;
- madt_proc[1].id = ACPI_MADT_TYPE_LOCAL_X2APIC;
- madt_proc[1].handler = acpi_parse_x2apic;
- ret = acpi_table_parse_entries_array(ACPI_SIG_MADT,
- sizeof(struct acpi_table_madt),
- madt_proc, ARRAY_SIZE(madt_proc), MAX_LOCAL_APIC);
- if (ret < 0) {
- pr_err("Error parsing LAPIC/X2APIC entries\n");
- return ret;
- }
-
- count = madt_proc[0].count;
- x2count = madt_proc[1].count;
+ count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC,
+ acpi_parse_lapic, MAX_LOCAL_APIC);
+ has_lapic_cpus = count > 0;
+ x2count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_X2APIC,
+ acpi_parse_x2apic, MAX_LOCAL_APIC);
}
if (!count && !x2count) {
pr_err("No LAPIC entries present\n");
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
index cacf2ed..23d8aaf 100644
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@ -175,9 +175,6 @@ int x64_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
frame = get_sigframe(ksig, regs, sizeof(struct rt_sigframe), &fp);
uc_flags = frame_uc_flags(regs);
- if (setup_signal_shadow_stack(ksig))
- return -EFAULT;
-
if (!user_access_begin(frame, sizeof(*frame)))
return -EFAULT;
@@ -198,6 +195,9 @@ int x64_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
return -EFAULT;
}
+ if (setup_signal_shadow_stack(ksig))
+ return -EFAULT;
+
/* Set up registers for signal handler */
regs->di = ksig->sig;
/* In case the signal handler was declared without prototypes */
