Commit 9f159ae0 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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

Pull x86 fixes from Thomas Gleixner:
 "A set of fixes for x86:

   - Fix the bogus detection of 32bit user mode for uretprobes which
     caused corruption of the user return address resulting in
     application crashes. In the uprobes handler in_ia32_syscall() is
     obviously always returning false on a 64bit kernel. Use
     user_64bit_mode() instead which works correctly.

   - Prevent large page splitting when ftrace flips RW/RO on the kernel
     text which caused iTLB performance issues. Ftrace wants to be
     converted to text_poke() which avoids the problem, but for now
     allow large page preservation in the static protections check when
     the change request spawns a full large page.

   - Prevent arch_dynirq_lower_bound() from returning 0 when the IOAPIC
     is configured via device tree. In the device tree case the GSI 1:1
     mapping is meaningless therefore the lower bound which protects the
     GSI range on ACPI machines is irrelevant. Return the lower bound
     which the core hands to the function instead of blindly returning 0
     which causes the core to allocate the invalid virtual interupt
     number 0 which in turn prevents all drivers from allocating and
     requesting an interrupt.

   - Remove the bogus initialization of LDR and DFR in the 32bit bigsmp
     APIC driver. That uses physical destination mode where LDR/DFR are
     ignored, but the initialization and the missing clear of LDR caused
     the APIC to be left in a inconsistent state on kexec/reboot.

   - Clear LDR when clearing the APIC registers so the APIC is in a well
     defined state.

   - Initialize variables proper in the find_trampoline_placement()
     code.

   - Silence GCC( build warning for the real mode part of the build"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/cpa: Prevent large page split when ftrace flips RW on kernel text
  x86/build: Add -Wnoaddress-of-packed-member to REALMODE_CFLAGS, to silence GCC9 build warning
  x86/boot/compressed/64: Fix missing initialization in find_trampoline_placement()
  x86/apic: Include the LDR when clearing out APIC registers
  x86/apic: Do not initialize LDR and DFR for bigsmp
  uprobes/x86: Fix detection of 32-bit user mode
  x86/apic: Fix arch_dynirq_lower_bound() bug for DT enabled machines
parents 5fb181cb 7af01450

arch/x86/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -38,6 +38,7 @@ REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -DDISABLE_BRANCH_PROFILING \ 


REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding)

REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -fno-stack-protector)

REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -Wno-address-of-packed-member)

REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align4))

export REALMODE_CFLAGS

arch/x86/boot/compressed/pgtable_64.c

+1 −1
Original line number Diff line number Diff line
@@ -72,7 +72,7 @@ static unsigned long find_trampoline_placement(void) 


	/* Find the first usable memory region under bios_start. */

	for (i = boot_params->e820_entries - 1; i >= 0; i--) {

		unsigned long new;

		unsigned long new = bios_start;



		entry = &boot_params->e820_table[i];

arch/x86/kernel/apic/apic.c

+4 −0
Original line number Diff line number Diff line
@@ -1179,6 +1179,10 @@ void clear_local_APIC(void) 
	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);

	v = apic_read(APIC_LVT1);

	apic_write(APIC_LVT1, v | APIC_LVT_MASKED);

	if (!x2apic_enabled()) {

		v = apic_read(APIC_LDR) & ~APIC_LDR_MASK;

		apic_write(APIC_LDR, v);

	}

	if (maxlvt >= 4) {

		v = apic_read(APIC_LVTPC);

		apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);

arch/x86/kernel/apic/bigsmp_32.c

+2 −22
Original line number Diff line number Diff line
@@ -38,32 +38,12 @@ static int bigsmp_early_logical_apicid(int cpu) 
	return early_per_cpu(x86_cpu_to_apicid, cpu);

}



static inline unsigned long calculate_ldr(int cpu)

{

	unsigned long val, id;



	val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;

	id = per_cpu(x86_bios_cpu_apicid, cpu);

	val |= SET_APIC_LOGICAL_ID(id);



	return val;

}



/*

 * Set up the logical destination ID.

 *

 * Intel recommends to set DFR, LDR and TPR before enabling

 * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel

 * document number 292116).  So here it goes...

 * bigsmp enables physical destination mode

 * and doesn't use LDR and DFR

 */

static void bigsmp_init_apic_ldr(void)

{

	unsigned long val;

	int cpu = smp_processor_id();



	apic_write(APIC_DFR, APIC_DFR_FLAT);

	val = calculate_ldr(cpu);

	apic_write(APIC_LDR, val);

}



static void bigsmp_setup_apic_routing(void)

arch/x86/kernel/apic/io_apic.c

+7 −1
Original line number Diff line number Diff line
@@ -2438,7 +2438,13 @@ unsigned int arch_dynirq_lower_bound(unsigned int from) 
	 * dmar_alloc_hwirq() may be called before setup_IO_APIC(), so use

	 * gsi_top if ioapic_dynirq_base hasn't been initialized yet.

	 */

	return ioapic_initialized ? ioapic_dynirq_base : gsi_top;

	if (!ioapic_initialized)

		return gsi_top;

	/*

	 * For DT enabled machines ioapic_dynirq_base is irrelevant and not

	 * updated. So simply return @from if ioapic_dynirq_base == 0.

	 */

	return ioapic_dynirq_base ? : from;

}



#ifdef CONFIG_X86_32

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