linux-stable/arch/x86
Tony Luck ce0fa3e56a x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages
Speculative processor accesses may reference any memory that has a
valid page table entry.  While a speculative access won't generate
a machine check, it will log the error in a machine check bank. That
could cause escalation of a subsequent error since the overflow bit
will be then set in the machine check bank status register.

Code has to be double-plus-tricky to avoid mentioning the 1:1 virtual
address of the page we want to map out otherwise we may trigger the
very problem we are trying to avoid.  We use a non-canonical address
that passes through the usual Linux table walking code to get to the
same "pte".

Thanks to Dave Hansen for reviewing several iterations of this.

Also see:

  http://marc.info/?l=linux-mm&m=149860136413338&w=2

Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Elliott, Robert (Persistent Memory) <elliott@hpe.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170816171803.28342-1-tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-17 10:30:49 +02:00
..
boot x86/mm: Provide general kernel support for memory encryption 2017-07-18 11:38:00 +02:00
configs Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-05-01 20:51:12 -07:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-07-14 22:49:50 -07:00
entry Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm 2017-07-08 12:17:25 -07:00
events Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 18:08:06 -07:00
hyperv char/misc patches for 4.12-rc1 2017-05-04 19:15:35 -07:00
ia32 sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h> 2017-03-02 08:42:36 +01:00
include x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages 2017-08-17 10:30:49 +02:00
kernel x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages 2017-08-17 10:30:49 +02:00
kvm kvm/x86/svm: Support Secure Memory Encryption within KVM 2017-07-18 11:38:04 +02:00
lguest Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-05-01 20:51:12 -07:00
lib x86/boot: Add early cmdline parsing for options with arguments 2017-07-18 11:38:06 +02:00
math-emu x86/ldt: Rename ldt_struct::size to ::nr_entries 2017-06-08 09:28:21 +02:00
mm x86/mm/dump_pagetables: Speed up page tables dump for CONFIG_KASAN=y 2017-07-25 11:22:09 +02:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-07-05 12:31:59 -07:00
oprofile
pci x86, mpparse, x86/acpi, x86/PCI, x86/dmi, SFI: Use memremap() for RAM mappings 2017-07-18 11:37:58 +02:00
platform x86/efi: Update EFI pagetable creation to work with SME 2017-07-18 11:38:02 +02:00
power x86/boot/e820: Introduce the bootloader provided e820_table_firmware[] table 2017-07-05 10:09:02 +02:00
purgatory kasan: do not sanitize kexec purgatory 2017-03-31 17:13:30 -07:00
ras x86/mce: Merge mce_amd_inj into mce-inject 2017-06-14 07:32:07 +02:00
realmode x86/boot/realmode: Check for memory encryption on the APs 2017-07-18 11:38:04 +02:00
tools
um Merge branch 'for-linus-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2017-07-15 10:49:33 -07:00
video
xen x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y 2017-07-21 10:05:19 +02:00
.gitignore
Kbuild
Kconfig x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y 2017-07-21 10:05:19 +02:00
Kconfig.cpu
Kconfig.debug usb/early: Add driver for xhci debug capability 2017-03-21 12:30:05 +01:00
Makefile Kbuild updates for v4.13 2017-07-07 14:09:24 -07:00
Makefile.um
Makefile_32.cpu kbuild: remove cc-option-align 2017-06-25 12:43:00 +09:00