linux/arch/x86/kernel
Tony Luck 17fae1294a x86/{mce,mm}: Unmap the entire page if the whole page is affected and poisoned
An interesting thing happened when a guest Linux instance took a machine
check. The VMM unmapped the bad page from guest physical space and
passed the machine check to the guest.

Linux took all the normal actions to offline the page from the process
that was using it. But then guest Linux crashed because it said there
was a second machine check inside the kernel with this stack trace:

do_memory_failure
    set_mce_nospec
         set_memory_uc
              _set_memory_uc
                   change_page_attr_set_clr
                        cpa_flush
                             clflush_cache_range_opt

This was odd, because a CLFLUSH instruction shouldn't raise a machine
check (it isn't consuming the data). Further investigation showed that
the VMM had passed in another machine check because is appeared that the
guest was accessing the bad page.

Fix is to check the scope of the poison by checking the MCi_MISC register.
If the entire page is affected, then unmap the page. If only part of the
page is affected, then mark the page as uncacheable.

This assumes that VMMs will do the logical thing and pass in the "whole
page scope" via the MCi_MISC register (since they unmapped the entire
page).

  [ bp: Adjust to x86/entry changes. ]

Fixes: 284ce4011b ("x86/memory_failure: Introduce {set, clear}_mce_nospec()")
Reported-by: Jue Wang <juew@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jue Wang <juew@google.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200520163546.GA7977@agluck-desk2.amr.corp.intel.com
2020-06-11 15:19:17 +02:00
..
acpi mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
apic x86/entry: Convert SMP system vectors to IDTENTRY_SYSVEC 2020-06-11 15:15:14 +02:00
cpu x86/{mce,mm}: Unmap the entire page if the whole page is affected and poisoned 2020-06-11 15:19:17 +02:00
fpu Most of the changes here related to 'XSAVES supervisor state' support, 2020-06-01 14:09:26 -07:00
kprobes x86/entry: Unbreak __irqentry_text_start/end magic 2020-06-11 15:15:29 +02:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
alternative.c x86/int3: Inline bsearch() 2020-06-11 15:14:54 +02:00
amd_gart_64.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
amd_nb.c x86/amd_nb: Add AMD family 17h model 60h PCI IDs 2020-05-22 18:24:40 +02:00
apb_timer.c x86/apb_timer: Drop unused TSC calibration 2020-05-27 13:05:59 +02:00
aperture_64.c
apm_32.c
asm-offsets.c efi/x86: Avoid using code32_start 2020-03-08 09:58:17 +01:00
asm-offsets_32.c x86 entry code updates: 2020-03-30 19:14:28 -07:00
asm-offsets_64.c x86/entry: Remove DBn stacks 2020-06-11 15:15:23 +02:00
audit_64.c x86/audit: Fix a -Wmissing-prototypes warning for ia32_classify_syscall() 2020-05-19 18:03:07 +02:00
bootflag.c
check.c
cpuid.c
crash.c x86/crash: Use resource_size() 2020-01-09 14:40:03 +01:00
crash_core_32.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
crash_core_64.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
crash_dump_32.c
crash_dump_64.c fs/core/vmcore: Move sev_active() reference to x86 arch code 2019-08-09 22:52:10 +10:00
devicetree.c
doublefault_32.c x86/entry: Convert double fault exception to IDTENTRY_DF 2020-06-11 15:15:03 +02:00
dumpstack.c kernel: rename show_stack_loglvl() => show_stack() 2020-06-09 09:39:13 -07:00
dumpstack_32.c x86/32: Remove CONFIG_DOUBLEFAULT 2020-04-14 14:24:05 +02:00
dumpstack_64.c x86/entry: Remove DBn stacks 2020-06-11 15:15:23 +02:00
e820.c crash_dump: Remove no longer used saved_max_pfn 2020-04-15 11:21:54 +02:00
early-quirks.c x86/intel: Disable HPET on Intel Ice Lake platforms 2019-11-29 12:17:58 +01:00
early_printk.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
ebda.c
eisa.c
espfix_64.c mm: introduce include/linux/pgtable.h 2020-06-09 09:39:13 -07:00
ftrace.c Linux 5.7-rc6 2020-05-18 13:09:37 +03:00
ftrace_32.S x86: Change {JMP,CALL}_NOSPEC argument 2020-04-30 20:14:34 +02:00
ftrace_64.S x86/entry/64: Move non entry code into .text section 2020-06-11 15:14:37 +02:00
head32.c
head64.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
head_32.S x86/boot: Remove KEEP_SEGMENTS support 2020-02-22 23:37:37 +01:00
head_64.S x86/entry: Remove the apic/BUILD interrupt leftovers 2020-06-11 15:15:16 +02:00
hpet.c remove ioremap_nocache and devm_ioremap_nocache 2020-01-06 09:45:59 +01:00
hw_breakpoint.c x86/entry: Optimize local_db_save() for virt 2020-06-11 15:15:22 +02:00
i8237.c
i8253.c x86/timer: Skip PIT initialization on modern chipsets 2019-06-29 11:35:35 +02:00
i8259.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
idt.c x86/idt: Consolidate idt functionality 2020-06-11 15:15:26 +02:00
ima_arch.c EFI updates for v5.7: 2020-02-26 15:21:22 +01:00
io_delay.c
ioport.c x86/ioperm: Prevent a memory leak when fork fails 2020-05-28 21:36:20 +02:00
irq.c x86/entry: Convert KVM vectors to IDTENTRY_SYSVEC* 2020-06-11 15:15:15 +02:00
irq_32.c x86/irq: Rework handle_irq() for 64-bit 2020-06-11 15:15:12 +02:00
irq_64.c x86/entry/64: Move do_softirq_own_stack() to C 2020-06-11 15:15:07 +02:00
irq_work.c x86/entry: Convert various system vectors 2020-06-11 15:15:14 +02:00
irqflags.S x86/asm: Change all ENTRY+ENDPROC to SYM_FUNC_* 2019-10-18 11:58:33 +02:00
irqinit.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
itmt.c sysctl: pass kernel pointers to ->proc_handler 2020-04-27 02:07:40 -04:00
jailhouse.c x86/jailhouse: Only enable platform UARTs if available 2019-10-10 15:43:59 +02:00
jump_label.c x86/jump_label: Move 'inline' keyword placement 2020-03-27 11:05:41 +01:00
kdebugfs.c x86/boot: Introduce setup_indirect 2019-11-12 16:21:15 +01:00
kexec-bzimage64.c efi/x86: Make fw_vendor, config_table and runtime sysfs nodes x86 specific 2020-02-23 21:59:42 +01:00
kgdb.c x86/apic: Provide and use helper for send_IPI_allbutself() 2019-07-25 16:12:00 +02:00
ksysfs.c x86/boot: Introduce setup_indirect 2019-11-12 16:21:15 +01:00
kvm.c x86/entry: Switch page fault exception to IDTENTRY_RAW 2020-06-11 15:15:09 +02:00
kvmclock.c x86/vdso: Use generic VDSO clock mode storage 2020-02-17 14:40:23 +01:00
ldt.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
machine_kexec_32.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
machine_kexec_64.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
Makefile Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching 2020-06-04 11:13:03 -07:00
mmconf-fam10h_64.c
module.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
mpparse.c x86/boot: Fix memory leak in default_get_smp_config() 2019-07-16 23:13:48 +02:00
msr.c x86/msr: Restrict MSR access when the kernel is locked down 2019-08-19 21:54:16 -07:00
nmi.c x86/entry: Rename trace_hardirqs_off_prepare() 2020-06-11 15:15:24 +02:00
nmi_selftest.c
paravirt-spinlocks.c
paravirt.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
paravirt_patch.c
pci-dma.c dma-mapping updates for 5.5-rc1 2019-11-28 11:16:43 -08:00
pci-iommu_table.c
pci-swiotlb.c dma-mapping: fix filename references 2019-09-03 08:36:30 +02:00
pcspeaker.c
perf_regs.c
platform-quirks.c
pmem.c
probe_roms.c
process.c Misc changes: 2020-06-05 11:18:53 -07:00
process.h x86: Use the correct SPDX License Identifier in headers 2019-10-01 20:31:35 +02:00
process_32.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
process_64.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
ptrace.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
pvclock.c x86/vdso: Use generic VDSO clock mode storage 2020-02-17 14:40:23 +01:00
quirks.c remove ioremap_nocache and devm_ioremap_nocache 2020-01-06 09:45:59 +01:00
reboot.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
reboot_fixups_32.c
relocate_kernel_32.S x86/asm: Annotate relocate_kernel_{32,64}.c 2019-10-18 09:53:19 +02:00
relocate_kernel_64.S x86/kexec: Make relocate_kernel_64.S objtool clean 2020-03-25 18:28:28 +01:00
resource.c
rtc.c
setup.c x86/setup: Add an initrdmem= option to specify initrd physical address 2020-04-27 09:28:16 +02:00
setup_percpu.c x86/mm: remove vmalloc faulting 2020-06-02 10:59:12 -07:00
signal.c Merge branch 'work.set_fs-exec' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-06-01 16:21:46 -07:00
signal_compat.c
smp.c x86/entry: Convert reschedule interrupt to IDTENTRY_SYSVEC_SIMPLE 2020-06-11 15:15:16 +02:00
smpboot.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
stacktrace.c x86 user stack frame reads: switch to explicit __get_user() 2020-02-15 17:26:26 -05:00
step.c
sys_ia32.c x86: switch cp_stat64() to unsafe_put_user() 2020-06-03 16:59:21 -04:00
sys_x86_64.c x86: Remove unneeded includes 2020-03-21 16:03:25 +01:00
sysfb.c
sysfb_efi.c x86/sysfb_efi: Add quirks for some devices with swapped width and height 2019-07-22 10:47:11 +02:00
sysfb_simplefb.c x86/sysfb: Fix check for bad VRAM size 2020-01-20 10:57:53 +01:00
tboot.c mmap locking API: add MMAP_LOCK_INITIALIZER 2020-06-09 09:39:14 -07:00
time.c x86/delay: Introduce TPAUSE delay 2020-05-07 16:06:20 +02:00
tls.c
tls.h
topology.c x86/smp: Replace cpu_up/down() with add/remove_cpu() 2020-03-25 12:59:35 +01:00
trace_clock.c
tracepoint.c x86/entry: Convert reschedule interrupt to IDTENTRY_SYSVEC_SIMPLE 2020-06-11 15:15:16 +02:00
traps.c x86/entry: Re-order #DB handler to avoid *SAN instrumentation 2020-06-11 15:15:28 +02:00
tsc.c x86/tsc: Add tsc_early_khz command line parameter 2020-05-21 23:07:00 +02:00
tsc_msr.c x86 timer updates: 2020-03-30 19:55:39 -07:00
tsc_sync.c x86: Fix a handful of typos 2020-02-16 20:58:06 +01:00
umip.c x86/umip: Make umip_insns static 2020-04-15 11:13:12 +02:00
unwind_frame.c x86/entry: Unbreak __irqentry_text_start/end magic 2020-06-11 15:15:29 +02:00
unwind_guess.c
unwind_orc.c x86/unwind/orc: Fix unwind_get_return_address_ptr() for inactive tasks 2020-05-22 19:55:17 +02:00
uprobes.c x86/apic, x86/uprobes: Correct parameter names in kernel-doc comments 2019-10-27 09:00:28 +01:00
verify_cpu.S x86/asm: Annotate local pseudo-functions 2019-10-18 10:04:04 +02:00
vm86_32.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
vmlinux.lds.S x86/entry: Unbreak __irqentry_text_start/end magic 2020-06-11 15:15:29 +02:00
vsmp_64.c
x86_init.c x86/kvm: Handle async page faults directly through do_page_fault() 2020-05-19 15:53:57 +02:00