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
......@@ -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
......
......@@ -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;
}
......
......@@ -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);
......
......@@ -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");
......
......@@ -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;
......
......@@ -611,6 +611,10 @@ static void check_xstate_against_struct(int nr)
* This essentially double-checks what the cpu told us about
* how large the XSAVE buffer needs to be. We are recalculating
* it to be safe.
*
* Dynamic XSAVE features allocate their own buffers and are not
* covered by these checks. Only the size of the buffer for task->fpu
* is checked here.
*/
static void do_extra_xstate_size_checks(void)
{
......@@ -673,6 +677,33 @@ static unsigned int __init get_xsaves_size(void)
return ebx;
}
/*
* Get the total size of the enabled xstates without the dynamic supervisor
* features.
*/
static unsigned int __init get_xsaves_size_no_dynamic(void)
{
u64 mask = xfeatures_mask_dynamic();
unsigned int size;
if (!mask)
return get_xsaves_size();
/* Disable dynamic features. */
wrmsrl(MSR_IA32_XSS, xfeatures_mask_supervisor());
/*
* Ask the hardware what size is required of the buffer.
* This is the size required for the task->fpu buffer.
*/
size = get_xsaves_size();
/* Re-enable dynamic features so XSAVES will work on them again. */
wrmsrl(MSR_IA32_XSS, xfeatures_mask_supervisor() | mask);
return size;
}
static unsigned int __init get_xsave_size(void)
{
unsigned int eax, ebx, ecx, edx;
......@@ -710,7 +741,7 @@ static int __init init_xstate_size(void)
xsave_size = get_xsave_size();
if (boot_cpu_has(X86_FEATURE_XSAVES))
possible_xstate_size = get_xsaves_size();
possible_xstate_size = get_xsaves_size_no_dynamic();
else
possible_xstate_size = xsave_size;
......
......@@ -134,10 +134,15 @@ static const struct freq_desc freq_desc_ann = {
.mask = 0x0f,
};
/* 24 MHz crystal? : 24 * 13 / 4 = 78 MHz */
/*
* 24 MHz crystal? : 24 * 13 / 4 = 78 MHz
* Frequency step for Lightning Mountain SoC is fixed to 78 MHz,
* so all the frequency entries are 78000.
*/
static const struct freq_desc freq_desc_lgm = {
.use_msr_plat = true,
.freqs = { 78000, 78000, 78000, 78000, 78000, 78000, 78000, 78000 },
.freqs = { 78000, 78000, 78000, 78000, 78000, 78000, 78000, 78000,
78000, 78000, 78000, 78000, 78000, 78000, 78000, 78000 },
.mask = 0x0f,
};
......
......@@ -32,7 +32,7 @@ KCOV_INSTRUMENT := n
# make up the standalone purgatory.ro
PURGATORY_CFLAGS_REMOVE := -mcmodel=kernel
PURGATORY_CFLAGS := -mcmodel=large -ffreestanding -fno-zero-initialized-in-bss
PURGATORY_CFLAGS := -mcmodel=large -ffreestanding -fno-zero-initialized-in-bss -g0
PURGATORY_CFLAGS += $(DISABLE_STACKLEAK_PLUGIN) -DDISABLE_BRANCH_PROFILING
PURGATORY_CFLAGS += -fno-stack-protector
......@@ -64,6 +64,9 @@ CFLAGS_sha256.o += $(PURGATORY_CFLAGS)
CFLAGS_REMOVE_string.o += $(PURGATORY_CFLAGS_REMOVE)
CFLAGS_string.o += $(PURGATORY_CFLAGS)
AFLAGS_REMOVE_setup-x86_$(BITS).o += -Wa,-gdwarf-2
AFLAGS_REMOVE_entry64.o += -Wa,-gdwarf-2
$(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE
$(call if_changed,ld)
......
......@@ -1169,24 +1169,26 @@ int crash_exclude_mem_range(struct crash_mem *mem,
unsigned long long mstart, unsigned long long mend)
{
int i, j;
unsigned long long start, end;
unsigned long long start, end, p_start, p_end;
struct crash_mem_range temp_range = {0, 0};
for (i = 0; i < mem->nr_ranges; i++) {
start = mem->ranges[i].start;
end = mem->ranges[i].end;
p_start = mstart;
p_end = mend;
if (mstart > end || mend < start)
continue;
/* Truncate any area outside of range */
if (mstart < start)
mstart = start;
p_start = start;
if (mend > end)
mend = end;
p_end = end;
/* Found completely overlapping range */
if (mstart == start && mend == end) {
if (p_start == start && p_end == end) {
mem->ranges[i].start = 0;
mem->ranges[i].end = 0;
if (i < mem->nr_ranges - 1) {
......@@ -1197,20 +1199,29 @@ int crash_exclude_mem_range(struct crash_mem *mem,
mem->ranges[j].end =
mem->ranges[j+1].end;
}
/*
* Continue to check if there are another overlapping ranges
* from the current position because of shifting the above
* mem ranges.
*/
i--;
mem->nr_ranges--;
continue;
}
mem->nr_ranges--;
return 0;
}
if (mstart > start && mend < end) {
if (p_start > start && p_end < end) {
/* Split original range */
mem->ranges[i].end = mstart - 1;
temp_range.start = mend + 1;
mem->ranges[i].end = p_start - 1;
temp_range.start = p_end + 1;
temp_range.end = end;
} else if (mstart != start)
mem->ranges[i].end = mstart - 1;
} else if (p_start != start)
mem->ranges[i].end = p_start - 1;
else
mem->ranges[i].start = mend + 1;
mem->ranges[i].start = p_end + 1;
break;
}
......@@ -1247,7 +1258,7 @@ int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
unsigned long long notes_addr;
unsigned long mstart, mend;
/* extra phdr for vmcoreinfo elf note */
/* extra phdr for vmcoreinfo ELF note */
nr_phdr = nr_cpus + 1;
nr_phdr += mem->nr_ranges;
......@@ -1255,7 +1266,7 @@ int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
* kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
* area (for example, ffffffff80000000 - ffffffffa0000000 on x86_64).
* I think this is required by tools like gdb. So same physical
* memory will be mapped in two elf headers. One will contain kernel
* memory will be mapped in two ELF headers. One will contain kernel
* text virtual addresses and other will have __va(physical) addresses.
*/
......@@ -1282,7 +1293,7 @@ int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
ehdr->e_ehsize = sizeof(Elf64_Ehdr);
ehdr->e_phentsize = sizeof(Elf64_Phdr);
/* Prepare one phdr of type PT_NOTE for each present cpu */
/* Prepare one phdr of type PT_NOTE for each present CPU */
for_each_present_cpu(cpu) {
phdr->p_type = PT_NOTE;
notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu));
......@@ -1324,10 +1335,10 @@ int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
phdr->p_align = 0;
ehdr->e_phnum++;
phdr++;
pr_debug("Crash PT_LOAD elf header. phdr=%p vaddr=0x%llx, paddr=0x%llx, sz=0x%llx e_phnum=%d p_offset=0x%llx\n",
pr_debug("Crash PT_LOAD ELF header. phdr=%p vaddr=0x%llx, paddr=0x%llx, sz=0x%llx e_phnum=%d p_offset=0x%llx\n",
phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz,
ehdr->e_phnum, phdr->p_offset);
phdr++;
}
*addr = buf;
......
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