Commit 50f6c7db authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'x86-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull x86 fixes from Ingo Molnar:
 "Misc fixes and small updates all around the place:

   - Fix mitigation state sysfs output

   - Fix an FPU xstate/sxave code assumption bug triggered by
     Architectural LBR support

   - Fix Lightning Mountain SoC TSC frequency enumeration bug

   - Fix kexec debug output

   - Fix kexec memory range assumption bug

   - Fix a boundary condition in the crash kernel code

   - Optimize porgatory.ro generation a bit

   - Enable ACRN guests to use X2APIC mode

   - Reduce a __text_poke() IRQs-off critical section for the benefit of
     PREEMPT_RT"

* tag 'x86-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/alternatives: Acquire pte lock with interrupts enabled
  x86/bugs/multihit: Fix mitigation reporting when VMX is not in use
  x86/fpu/xstate: Fix an xstate size check warning with architectural LBRs
  x86/purgatory: Don't generate debug info for purgatory.ro
  x86/tsr: Fix tsc frequency enumeration bug on Lightning Mountain SoC
  kexec_file: Correctly output debugging information for the PT_LOAD ELF header
  kexec: Improve & fix crash_exclude_mem_range() to handle overlapping ranges
  x86/crash: Correct the address boundary of function parameters
  x86/acrn: Remove redundant chars from ACRN signature
  x86/acrn: Allow ACRN guest to use X2APIC mode
parents 1195d58f a6d996cb

Documentation/admin-guide/hw-vuln/multihit.rst

+4 −0
Original line number Diff line number Diff line
@@ -80,6 +80,10 @@ The possible values in this file are: 
       - The processor is not vulnerable.

     * - KVM: Mitigation: Split huge pages

       - Software changes mitigate this issue.

     * - KVM: Mitigation: VMX unsupported

       - KVM is not vulnerable because Virtual Machine Extensions (VMX) is not supported.

     * - KVM: Mitigation: VMX disabled

       - KVM is not vulnerable because Virtual Machine Extensions (VMX) is disabled.

     * - KVM: Vulnerable

       - The processor is vulnerable, but no mitigation enabled

arch/x86/kernel/alternative.c

+3 −3
Original line number Diff line number Diff line
@@ -875,8 +875,6 @@ static void *__text_poke(void *addr, const void *opcode, size_t len) 
	 */

	BUG_ON(!pages[0] || (cross_page_boundary && !pages[1]));



	local_irq_save(flags);



	/*

	 * Map the page without the global bit, as TLB flushing is done with

	 * flush_tlb_mm_range(), which is intended for non-global PTEs.
@@ -893,6 +891,8 @@ static void *__text_poke(void *addr, const void *opcode, size_t len) 
	 */

	VM_BUG_ON(!ptep);



	local_irq_save(flags);



	pte = mk_pte(pages[0], pgprot);

	set_pte_at(poking_mm, poking_addr, ptep, pte);
@@ -942,8 +942,8 @@ static void *__text_poke(void *addr, const void *opcode, size_t len) 
	 */

	BUG_ON(memcmp(addr, opcode, len));



	pte_unmap_unlock(ptep, ptl);

	local_irq_restore(flags);

	pte_unmap_unlock(ptep, ptl);

	return addr;

}

arch/x86/kernel/cpu/acrn.c

+4 −8
Original line number Diff line number Diff line
@@ -11,14 +11,15 @@ 


#include <linux/interrupt.h>

#include <asm/apic.h>

#include <asm/cpufeatures.h>

#include <asm/desc.h>

#include <asm/hypervisor.h>

#include <asm/idtentry.h>

#include <asm/irq_regs.h>



static uint32_t __init acrn_detect(void)

static u32 __init acrn_detect(void)

{

	return hypervisor_cpuid_base("ACRNACRNACRN\0\0", 0);

	return hypervisor_cpuid_base("ACRNACRNACRN", 0);

}



static void __init acrn_init_platform(void)
@@ -29,12 +30,7 @@ static void __init acrn_init_platform(void) 


static bool acrn_x2apic_available(void)

{

	/*

	 * x2apic is not supported for now. Future enablement will have to check

	 * X86_FEATURE_X2APIC to determine whether x2apic is supported in the

	 * guest.

	 */

	return false;

	return boot_cpu_has(X86_FEATURE_X2APIC);

}



static void (*acrn_intr_handler)(void);

arch/x86/kernel/cpu/bugs.c

+7 −1
Original line number Diff line number Diff line
@@ -31,6 +31,7 @@ 
#include <asm/intel-family.h>

#include <asm/e820/api.h>

#include <asm/hypervisor.h>

#include <asm/tlbflush.h>



#include "cpu.h"
@@ -1549,7 +1550,12 @@ static ssize_t l1tf_show_state(char *buf) 


static ssize_t itlb_multihit_show_state(char *buf)

{

	if (itlb_multihit_kvm_mitigation)

	if (!boot_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||

	    !boot_cpu_has(X86_FEATURE_VMX))

		return sprintf(buf, "KVM: Mitigation: VMX unsupported\n");

	else if (!(cr4_read_shadow() & X86_CR4_VMXE))

		return sprintf(buf, "KVM: Mitigation: VMX disabled\n");

	else if (itlb_multihit_kvm_mitigation)

		return sprintf(buf, "KVM: Mitigation: Split huge pages\n");

	else

		return sprintf(buf, "KVM: Vulnerable\n");

arch/x86/kernel/crash.c

+1 −1
Original line number Diff line number Diff line
@@ -230,7 +230,7 @@ static int elf_header_exclude_ranges(struct crash_mem *cmem) 
	int ret = 0;



	/* Exclude the low 1M because it is always reserved */

	ret = crash_exclude_mem_range(cmem, 0, 1<<20);

	ret = crash_exclude_mem_range(cmem, 0, (1<<20)-1);

	if (ret)

		return ret;

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