Merge branch 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "A couple of fixlets for x86:

   - Fix the ESPFIX double fault handling for 5-level pagetables

   - Fix the commandline parsing for 'apic=' on 32bit systems and update
     documentation

   - Make zombie stack traces reliable

   - Fix kexec with stack canary

   - Fix the delivery mode for APICs which was missed when the x86
     vector management was converted to single target delivery. Caused a
     regression due to the broken hardware which ignores affinity
     settings in lowest prio delivery mode.

   - Unbreak modules when AMD memory encryption is enabled

   - Remove an unused parameter of prepare_switch_to"

* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Switch all APICs to Fixed delivery mode
  x86/apic: Update the 'apic=' description of setting APIC driver
  x86/apic: Avoid wrong warning when parsing 'apic=' in X86-32 case
  x86-32: Fix kexec with stack canary (CONFIG_CC_STACKPROTECTOR)
  x86: Remove unused parameter of prepare_switch_to
  x86/stacktrace: Make zombie stack traces reliable
  x86/mm: Unbreak modules that use the DMA API
  x86/build: Make isoimage work on Debian
  x86/espfix/64: Fix espfix double-fault handling on 5-level systems

Author: torvalds

Documentation/admin-guide/kernel-parameters.txt

@@ -328,11 +328,15 @@
 			not play well with APC CPU idle - disable it if you have
 			APC and your system crashes randomly.
 
-	apic=		[APIC,X86-32] Advanced Programmable Interrupt Controller
+	apic=		[APIC,X86] Advanced Programmable Interrupt Controller
 			Change the output verbosity whilst booting
 			Format: { quiet (default) | verbose | debug }
 			Change the amount of debugging information output
 			when initialising the APIC and IO-APIC components.
+			For X86-32, this can also be used to specify an APIC
+			driver name.
+			Format: apic=driver_name
+			Examples: apic=bigsmp
 
 	apic_extnmi=	[APIC,X86] External NMI delivery setting
 			Format: { bsp (default) | all | none }

arch/x86/boot/genimage.sh

@@ -80,39 +80,43 @@ genfdimage288() {
 	mcopy $FBZIMAGE w:linux
 }
 
-genisoimage() {
+geniso() {
 	tmp_dir=`dirname $FIMAGE`/isoimage
 	rm -rf $tmp_dir
 	mkdir $tmp_dir
-	for i in lib lib64 share end ; do
+	for i in lib lib64 share ; do
 		for j in syslinux ISOLINUX ; do
 			if [ -f /usr/$i/$j/isolinux.bin ] ; then
 				isolinux=/usr/$i/$j/isolinux.bin
-				cp $isolinux $tmp_dir
 			fi
 		done
 		for j in syslinux syslinux/modules/bios ; do
 			if [ -f /usr/$i/$j/ldlinux.c32 ]; then
 				ldlinux=/usr/$i/$j/ldlinux.c32
-				cp $ldlinux $tmp_dir
 			fi
 		done
 		if [ -n "$isolinux" -a -n "$ldlinux" ] ; then
 			break
 		fi
-		if [ $i = end -a -z "$isolinux" ] ; then
-			echo 'Need an isolinux.bin file, please install syslinux/isolinux.'
-			exit 1
-		fi
 	done
+	if [ -z "$isolinux" ] ; then
+		echo 'Need an isolinux.bin file, please install syslinux/isolinux.'
+		exit 1
+	fi
+	if [ -z "$ldlinux" ] ; then
+		echo 'Need an ldlinux.c32 file, please install syslinux/isolinux.'
+		exit 1
+	fi
+	cp $isolinux $tmp_dir
+	cp $ldlinux $tmp_dir
 	cp $FBZIMAGE $tmp_dir/linux
 	echo "$KCMDLINE" > $tmp_dir/isolinux.cfg
 	if [ -f "$FDINITRD" ] ; then
 		cp "$FDINITRD" $tmp_dir/initrd.img
 	fi
-	mkisofs -J -r -input-charset=utf-8 -quiet -o $FIMAGE -b isolinux.bin \
-		-c boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table \
-		$tmp_dir
+	genisoimage -J -r -input-charset=utf-8 -quiet -o $FIMAGE \
+		-b isolinux.bin -c boot.cat -no-emul-boot -boot-load-size 4 \
+		-boot-info-table $tmp_dir
 	isohybrid $FIMAGE 2>/dev/null || true
 	rm -rf $tmp_dir
 }
@@ -121,6 +125,6 @@ case $1 in
 	bzdisk)     genbzdisk;;
 	fdimage144) genfdimage144;;
 	fdimage288) genfdimage288;;
-	isoimage)   genisoimage;;
+	isoimage)   geniso;;
 	*)          echo 'Unknown image format'; exit 1;
 esac

arch/x86/include/asm/switch_to.h

@@ -16,8 +16,7 @@ void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
 		      struct tss_struct *tss);
 
 /* This runs runs on the previous thread's stack. */
-static inline void prepare_switch_to(struct task_struct *prev,
-				     struct task_struct *next)
+static inline void prepare_switch_to(struct task_struct *next)
 {
 #ifdef CONFIG_VMAP_STACK
 	/*
@@ -70,7 +69,7 @@ struct fork_frame {
 
 #define switch_to(prev, next, last)					\
 do {									\
-	prepare_switch_to(prev, next);					\
+	prepare_switch_to(next);					\
 									\
 	((last) = __switch_to_asm((prev), (next)));			\
 } while (0)

arch/x86/kernel/apic/apic.c

@@ -2626,11 +2626,13 @@ static int __init apic_set_verbosity(char *arg)
 		apic_verbosity = APIC_DEBUG;
 	else if (strcmp("verbose", arg) == 0)
 		apic_verbosity = APIC_VERBOSE;
+#ifdef CONFIG_X86_64
 	else {
 		pr_warning("APIC Verbosity level %s not recognised"
 			" use apic=verbose or apic=debug\n", arg);
 		return -EINVAL;
 	}
+#endif
 
 	return 0;
 }

arch/x86/kernel/apic/apic_flat_64.c

@@ -151,7 +151,7 @@ static struct apic apic_flat __ro_after_init = {
 	.apic_id_valid			= default_apic_id_valid,
 	.apic_id_registered		= flat_apic_id_registered,
 
-	.irq_delivery_mode		= dest_LowestPrio,
+	.irq_delivery_mode		= dest_Fixed,
 	.irq_dest_mode			= 1, /* logical */
 
 	.disable_esr			= 0,

arch/x86/kernel/apic/apic_noop.c

@@ -110,7 +110,7 @@ struct apic apic_noop __ro_after_init = {
 	.apic_id_valid			= default_apic_id_valid,
 	.apic_id_registered		= noop_apic_id_registered,
 
-	.irq_delivery_mode		= dest_LowestPrio,
+	.irq_delivery_mode		= dest_Fixed,
 	/* logical delivery broadcast to all CPUs: */
 	.irq_dest_mode			= 1,
 

arch/x86/kernel/apic/msi.c

@@ -39,17 +39,13 @@ static void irq_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
 		((apic->irq_dest_mode == 0) ?
 			MSI_ADDR_DEST_MODE_PHYSICAL :
 			MSI_ADDR_DEST_MODE_LOGICAL) |
-		((apic->irq_delivery_mode != dest_LowestPrio) ?
-			MSI_ADDR_REDIRECTION_CPU :
-			MSI_ADDR_REDIRECTION_LOWPRI) |
+		MSI_ADDR_REDIRECTION_CPU |
 		MSI_ADDR_DEST_ID(cfg->dest_apicid);
 
 	msg->data =
 		MSI_DATA_TRIGGER_EDGE |
 		MSI_DATA_LEVEL_ASSERT |
-		((apic->irq_delivery_mode != dest_LowestPrio) ?
-			MSI_DATA_DELIVERY_FIXED :
-			MSI_DATA_DELIVERY_LOWPRI) |
+		MSI_DATA_DELIVERY_FIXED |
 		MSI_DATA_VECTOR(cfg->vector);
 }
 

arch/x86/kernel/apic/probe_32.c

@@ -105,7 +105,7 @@ static struct apic apic_default __ro_after_init = {
 	.apic_id_valid			= default_apic_id_valid,
 	.apic_id_registered		= default_apic_id_registered,
 
-	.irq_delivery_mode		= dest_LowestPrio,
+	.irq_delivery_mode		= dest_Fixed,
 	/* logical delivery broadcast to all CPUs: */
 	.irq_dest_mode			= 1,
 

arch/x86/kernel/apic/x2apic_cluster.c

@@ -184,7 +184,7 @@ static struct apic apic_x2apic_cluster __ro_after_init = {
 	.apic_id_valid			= x2apic_apic_id_valid,
 	.apic_id_registered		= x2apic_apic_id_registered,
 
-	.irq_delivery_mode		= dest_LowestPrio,
+	.irq_delivery_mode		= dest_Fixed,
 	.irq_dest_mode			= 1, /* logical */
 
 	.disable_esr			= 0,

arch/x86/kernel/machine_kexec_32.c

@@ -48,8 +48,6 @@ static void load_segments(void)
 		"\tmovl $"STR(__KERNEL_DS)",%%eax\n"
 		"\tmovl %%eax,%%ds\n"
 		"\tmovl %%eax,%%es\n"
-		"\tmovl %%eax,%%fs\n"
-		"\tmovl %%eax,%%gs\n"
 		"\tmovl %%eax,%%ss\n"
 		: : : "eax", "memory");
 #undef STR
@@ -232,8 +230,8 @@ void machine_kexec(struct kimage *image)
 	 * The gdt & idt are now invalid.
 	 * If you want to load them you must set up your own idt & gdt.
 	 */
-	set_gdt(phys_to_virt(0), 0);
 	idt_invalidate(phys_to_virt(0));
+	set_gdt(phys_to_virt(0), 0);
 
 	/* now call it */
 	image->start = relocate_kernel_ptr((unsigned long)image->head,

arch/x86/kernel/stacktrace.c

@@ -164,8 +164,12 @@ int save_stack_trace_tsk_reliable(struct task_struct *tsk,
 {
 	int ret;
 
+	/*
+	 * If the task doesn't have a stack (e.g., a zombie), the stack is
+	 * "reliably" empty.
+	 */
 	if (!try_get_task_stack(tsk))
-		return -EINVAL;
+		return 0;
 
 	ret = __save_stack_trace_reliable(trace, tsk);
 

arch/x86/kernel/traps.c

@@ -361,7 +361,7 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
 	 *
 	 * No need for ist_enter here because we don't use RCU.
 	 */
-	if (((long)regs->sp >> PGDIR_SHIFT) == ESPFIX_PGD_ENTRY &&
+	if (((long)regs->sp >> P4D_SHIFT) == ESPFIX_PGD_ENTRY &&
 		regs->cs == __KERNEL_CS &&
 		regs->ip == (unsigned long)native_irq_return_iret)
 	{

arch/x86/mm/mem_encrypt.c

@@ -405,13 +405,13 @@ bool sme_active(void)
 {
 	return sme_me_mask && !sev_enabled;
 }
-EXPORT_SYMBOL_GPL(sme_active);
+EXPORT_SYMBOL(sme_active);
 
 bool sev_active(void)
 {
 	return sme_me_mask && sev_enabled;
 }
-EXPORT_SYMBOL_GPL(sev_active);
+EXPORT_SYMBOL(sev_active);
 
 static const struct dma_map_ops sev_dma_ops = {
 	.alloc                  = sev_alloc,

drivers/pci/host/pci-hyperv.c

@@ -985,9 +985,7 @@ static u32 hv_compose_msi_req_v1(
 	int_pkt->wslot.slot = slot;
 	int_pkt->int_desc.vector = vector;
 	int_pkt->int_desc.vector_count = 1;
-	int_pkt->int_desc.delivery_mode =
-		(apic->irq_delivery_mode == dest_LowestPrio) ?
-			dest_LowestPrio : dest_Fixed;
+	int_pkt->int_desc.delivery_mode = dest_Fixed;
 
 	/*
 	 * Create MSI w/ dummy vCPU set, overwritten by subsequent retarget in
@@ -1008,9 +1006,7 @@ static u32 hv_compose_msi_req_v2(
 	int_pkt->wslot.slot = slot;
 	int_pkt->int_desc.vector = vector;
 	int_pkt->int_desc.vector_count = 1;
-	int_pkt->int_desc.delivery_mode =
-		(apic->irq_delivery_mode == dest_LowestPrio) ?
-			dest_LowestPrio : dest_Fixed;
+	int_pkt->int_desc.delivery_mode = dest_Fixed;
 
 	/*
 	 * Create MSI w/ dummy vCPU set targeting just one vCPU, overwritten