Commit Graph

513 Commits

Author SHA1 Message Date
Ard Biesheuvel
2e6eb40ca5 efi/x86: Fix incorrect invocation of PciIo->Attributes()
The following commit:

  2c3625cb9f ("efi/x86: Fold __setup_efi_pci32() and __setup_efi_pci64() into one function")

... merged the two versions of __setup_efi_pciXX(), without taking into
account that the 32-bit version used a rather dodgy trick to pass an
immediate 0 constant as argument for a uint64_t parameter.

The issue is caused by the fact that on x86, UEFI protocol method calls
are redirected via struct efi_config::call(), which is a variadic function,
and so the compiler has to infer the types of the parameters from the
arguments rather than from the prototype.

As the 32-bit x86 calling convention passes arguments via the stack,
passing the unqualified constant 0 twice is the same as passing 0ULL,
which is why the 32-bit code in __setup_efi_pci32() contained the
following call:

  status = efi_early->call(pci->attributes, pci,
                           EfiPciIoAttributeOperationGet, 0, 0,
                           &attributes);

to invoke this UEFI protocol method:

  typedef
  EFI_STATUS
  (EFIAPI *EFI_PCI_IO_PROTOCOL_ATTRIBUTES) (
    IN  EFI_PCI_IO_PROTOCOL                     *This,
    IN  EFI_PCI_IO_PROTOCOL_ATTRIBUTE_OPERATION Operation,
    IN  UINT64                                  Attributes,
    OUT UINT64                                  *Result OPTIONAL
    );

After the merge, we inadvertently ended up with this version for both
32-bit and 64-bit builds, breaking the latter.

So replace the two zeroes with the explicitly typed constant 0ULL,
which works as expected on both 32-bit and 64-bit builds.

Wilfried tested the 64-bit build, and I checked the generated assembly
of a 32-bit build with and without this patch, and they are identical.

Reported-by: Wilfried Klaebe <linux-kernel@lebenslange-mailadresse.de>
Tested-by: Wilfried Klaebe <linux-kernel@lebenslange-mailadresse.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdegoede@redhat.com
Cc: linux-efi@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-24 09:05:58 +02:00
Linus Torvalds
f4e5b30d80 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 updates and fixes from Thomas Gleixner:

 - Fix the (late) fallout from the vector management rework causing
   hlist corruption and irq descriptor reference leaks caused by a
   missing sanity check.

   The straight forward fix triggered another long standing issue to
   surface. The pre rework code hid the issue due to being way slower,
   but now the chance that user space sees an EBUSY error return when
   updating irq affinities is way higher, though quite a bunch of
   userspace tools do not handle it properly despite the fact that EBUSY
   could be returned for at least 10 years.

   It turned out that the EBUSY return can be avoided completely by
   utilizing the existing delayed affinity update mechanism for irq
   remapped scenarios as well. That's a bit more error handling in the
   kernel, but avoids fruitless fingerpointing discussions with tool
   developers.

 - Decouple PHYSICAL_MASK from AMD SME as its going to be required for
   the upcoming Intel memory encryption support as well.

 - Handle legacy device ACPI detection properly for newer platforms

 - Fix the wrong argument ordering in the vector allocation tracepoint

 - Simplify the IDT setup code for the APIC=n case

 - Use the proper string helpers in the MTRR code

 - Remove a stale unused VDSO source file

 - Convert the microcode update lock to a raw spinlock as its used in
   atomic context.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/intel_rdt: Enable CMT and MBM on new Skylake stepping
  x86/apic/vector: Print APIC control bits in debugfs
  genirq/affinity: Defer affinity setting if irq chip is busy
  x86/platform/uv: Use apic_ack_irq()
  x86/ioapic: Use apic_ack_irq()
  irq_remapping: Use apic_ack_irq()
  x86/apic: Provide apic_ack_irq()
  genirq/migration: Avoid out of line call if pending is not set
  genirq/generic_pending: Do not lose pending affinity update
  x86/apic/vector: Prevent hlist corruption and leaks
  x86/vector: Fix the args of vector_alloc tracepoint
  x86/idt: Simplify the idt_setup_apic_and_irq_gates()
  x86/platform/uv: Remove extra parentheses
  x86/mm: Decouple dynamic __PHYSICAL_MASK from AMD SME
  x86: Mark native_set_p4d() as __always_inline
  x86/microcode: Make the late update update_lock a raw lock for RT
  x86/mtrr: Convert to use strncpy_from_user() helper
  x86/mtrr: Convert to use match_string() helper
  x86/vdso: Remove unused file
  x86/i8237: Register device based on FADT legacy boot flag
2018-06-10 09:44:53 -07:00
Kirill A. Shutemov
94d49eb30e x86/mm: Decouple dynamic __PHYSICAL_MASK from AMD SME
AMD SME claims one bit from physical address to indicate whether the
page is encrypted or not. To achieve that we clear out the bit from
__PHYSICAL_MASK.

The capability to adjust __PHYSICAL_MASK is required beyond AMD SME.
For instance for upcoming Intel Multi-Key Total Memory Encryption.

Factor it out into a separate feature with own Kconfig handle.

It also helps with overhead of AMD SME. It saves more than 3k in .text
on defconfig + AMD_MEM_ENCRYPT:

	add/remove: 3/2 grow/shrink: 5/110 up/down: 189/-3753 (-3564)

We would need to return to this once we have infrastructure to patch
constants in code. That's good candidate for it.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-mm@kvack.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20180518113028.79825-1-kirill.shutemov@linux.intel.com
2018-06-06 13:38:01 +02:00
Linus Torvalds
5cef8c2a22 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:

 - Centaur CPU updates (David Wang)

 - AMD and other CPU topology enumeration improvements and fixes
   (Borislav Petkov, Thomas Gleixner, Suravee Suthikulpanit)

 - Continued 5-level paging work (Kirill A. Shutemov)

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Mark __pgtable_l5_enabled __initdata
  x86/mm: Mark p4d_offset() __always_inline
  x86/mm: Introduce the 'no5lvl' kernel parameter
  x86/mm: Stop pretending pgtable_l5_enabled is a variable
  x86/mm: Unify pgtable_l5_enabled usage in early boot code
  x86/boot/compressed/64: Fix trampoline page table address calculation
  x86/CPU: Move x86_cpuinfo::x86_max_cores assignment to detect_num_cpu_cores()
  x86/Centaur: Report correct CPU/cache topology
  x86/CPU: Move cpu_detect_cache_sizes() into init_intel_cacheinfo()
  x86/CPU: Make intel_num_cpu_cores() generic
  x86/CPU: Move cpu local function declarations to local header
  x86/CPU/AMD: Derive CPU topology from CPUID function 0xB when available
  x86/CPU: Modify detect_extended_topology() to return result
  x86/CPU/AMD: Calculate last level cache ID from number of sharing threads
  x86/CPU: Rename intel_cacheinfo.c to cacheinfo.c
  perf/events/amd/uncore: Fix amd_uncore_llc ID to use pre-defined cpu_llc_id
  x86/CPU/AMD: Have smp_num_siblings and cpu_llc_id always be present
  x86/Centaur: Initialize supported CPU features properly
2018-06-04 18:19:18 -07:00
Linus Torvalds
31a85cb35c Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:

 - decode x86 CPER data (Yazen Ghannam)

 - ignore unrealistically large option ROMs (Hans de Goede)

 - initialize UEFI secure boot state during Xen dom0 boot (Daniel Kiper)

 - additional minor tweaks and fixes.

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/capsule-loader: Don't output reset log when reset flags are not set
  efi/x86: Ignore unrealistically large option ROMs
  efi/x86: Fold __setup_efi_pci32() and __setup_efi_pci64() into one function
  efi: Align efi_pci_io_protocol typedefs to type naming convention
  efi/libstub/tpm: Make function efi_retrieve_tpm2_eventlog_1_2() static
  efi: Decode IA32/X64 Context Info structure
  efi: Decode IA32/X64 MS Check structure
  efi: Decode additional IA32/X64 Bus Check fields
  efi: Decode IA32/X64 Cache, TLB, and Bus Check structures
  efi: Decode UEFI-defined IA32/X64 Error Structure GUIDs
  efi: Decode IA32/X64 Processor Error Info Structure
  efi: Decode IA32/X64 Processor Error Section
  efi: Fix IA32/X64 Processor Error Record definition
  efi/cper: Remove the INDENT_SP silliness
  x86/xen/efi: Initialize UEFI secure boot state during dom0 boot
2018-06-04 16:31:06 -07:00
Linus Torvalds
8a6bd2f40e Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "An unfortunately larger set of fixes, but a large portion is
  selftests:

   - Fix the missing clusterid initializaiton for x2apic cluster
     management which caused boot failures due to IPIs being sent to the
     wrong cluster

   - Drop TX_COMPAT when a 64bit executable is exec()'ed from a compat
     task

   - Wrap access to __supported_pte_mask in __startup_64() where clang
     compile fails due to a non PC relative access being generated.

   - Two fixes for 5 level paging fallout in the decompressor:

      - Handle GOT correctly for paging_prepare() and
        cleanup_trampoline()

      - Fix the page table handling in cleanup_trampoline() to avoid
        page table corruption.

   - Stop special casing protection key 0 as this is inconsistent with
     the manpage and also inconsistent with the allocation map handling.

   - Override the protection key wen moving away from PROT_EXEC to
     prevent inaccessible memory.

   - Fix and update the protection key selftests to address breakage and
     to cover the above issue

   - Add a MOV SS self test"

[ Part of the x86 fixes were in the earlier core pull due to dependencies ]

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  x86/mm: Drop TS_COMPAT on 64-bit exec() syscall
  x86/apic/x2apic: Initialize cluster ID properly
  x86/boot/compressed/64: Fix moving page table out of trampoline memory
  x86/boot/compressed/64: Set up GOT for paging_prepare() and cleanup_trampoline()
  x86/pkeys: Do not special case protection key 0
  x86/pkeys/selftests: Add a test for pkey 0
  x86/pkeys/selftests: Save off 'prot' for allocations
  x86/pkeys/selftests: Fix pointer math
  x86/pkeys: Override pkey when moving away from PROT_EXEC
  x86/pkeys/selftests: Fix pkey exhaustion test off-by-one
  x86/pkeys/selftests: Add PROT_EXEC test
  x86/pkeys/selftests: Factor out "instruction page"
  x86/pkeys/selftests: Allow faults on unknown keys
  x86/pkeys/selftests: Avoid printf-in-signal deadlocks
  x86/pkeys/selftests: Remove dead debugging code, fix dprint_in_signal
  x86/pkeys/selftests: Stop using assert()
  x86/pkeys/selftests: Give better unexpected fault error messages
  x86/selftests: Add mov_to_ss test
  x86/mpx/selftests: Adjust the self-test to fresh distros that export the MPX ABI
  x86/pkeys/selftests: Adjust the self-test to fresh distros that export the pkeys ABI
  ...
2018-05-20 11:28:32 -07:00
Kirill A. Shutemov
372fddf709 x86/mm: Introduce the 'no5lvl' kernel parameter
This kernel parameter allows to force kernel to use 4-level paging even
if hardware and kernel support 5-level paging.

The option may be useful to work around regressions related to 5-level
paging.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180518103528.59260-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-19 11:56:57 +02:00
Kirill A. Shutemov
ad3fe525b9 x86/mm: Unify pgtable_l5_enabled usage in early boot code
Usually pgtable_l5_enabled is defined using cpu_feature_enabled().
cpu_feature_enabled() is not available in early boot code. We use
several different preprocessor tricks to get around it. It's messy.

Unify them all.

If cpu_feature_enabled() is not yet available, USE_EARLY_PGTABLE_L5 can
be defined before all includes. It makes pgtable_l5_enabled rely on
__pgtable_l5_enabled variable instead. This approach fits all early
users.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180518103528.59260-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-19 11:56:57 +02:00
Kirill A. Shutemov
30bbf728ba x86/boot/compressed/64: Fix trampoline page table address calculation
Hugh noticied that we calculate the address of the trampoline page table
incorrectly in cleanup_trampoline().

TRAMPOLINE_32BIT_PGTABLE_OFFSET has to be divided by sizeof(unsigned long),
since trampoline_32bit is an 'unsigned long' pointer.

TRAMPOLINE_32BIT_PGTABLE_OFFSET is zero so the bug doesn't have a
visible effect.

Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: e9d0e6330e ("x86/boot/compressed/64: Prepare new top-level page table for trampoline")
Link: http://lkml.kernel.org/r/20180518103528.59260-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-19 11:56:57 +02:00
Kirill A. Shutemov
589bb62be3 x86/boot/compressed/64: Fix moving page table out of trampoline memory
cleanup_trampoline() relocates the top-level page table out of
trampoline memory. We use 'top_pgtable' as our new top-level page table.

But if the 'top_pgtable' would be referenced from C in a usual way,
the address of the table will be calculated relative to RIP.
After kernel gets relocated, the address will be in the middle of
decompression buffer and the page table may get overwritten.
This leads to a crash.

We calculate the address of other page tables relative to the relocation
address. It makes them safe. We should do the same for 'top_pgtable'.

Calculate the address of 'top_pgtable' in assembly and pass down to
cleanup_trampoline().

Move the page table to .pgtable section where the rest of page tables
are. The section is @nobits so we save 4k in kernel image.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: e9d0e6330e ("x86/boot/compressed/64: Prepare new top-level page table for trampoline")
Link: http://lkml.kernel.org/r/20180516080131.27913-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-16 12:15:13 +02:00
Kirill A. Shutemov
5c9b0b1c49 x86/boot/compressed/64: Set up GOT for paging_prepare() and cleanup_trampoline()
Eric and Hugh have reported instant reboot due to my recent changes in
decompression code.

The root cause is that I didn't realize that we need to adjust GOT to be
able to run C code that early.

The problem is only visible with an older toolchain. Binutils >= 2.24 is
able to eliminate GOT references by replacing them with RIP-relative
address loads:

  https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commitdiff;h=80d873266dec

We need to adjust GOT two times:

 - before calling paging_prepare() using the initial load address
 - before calling C code from the relocated kernel

Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 194a9749c7 ("x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G")
Link: http://lkml.kernel.org/r/20180516080131.27913-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-16 12:15:13 +02:00
Hans de Goede
1de3a1be8a efi/x86: Ignore unrealistically large option ROMs
setup_efi_pci() tries to save a copy of each PCI option ROM as this may
be necessary for the device driver for the PCI device to have access too.

On some systems the efi_pci_io_protocol's romimage and romsize fields
contain invalid data, which looks a bit like pointers pointing back into
other EFI code or data. Interpreting these pointers as romsize leads to
a very large value and if we then try to alloc this amount of memory to
save a copy the alloc call fails.

This leads to a "Failed to alloc mem for rom" error being printed on the
EFI console for each PCI device.

This commit avoids the printing of these errors, by checking romsize before
doing the alloc and if it is larger then the EFI spec limit of 16 MiB
silently ignore the ROM fields instead of trying to alloc mem and fail.

Tested-by: Hans de Goede <hdegoede@redhat.com>
[ardb: deduplicate 32/64 bit changes, use SZ_16M symbolic constant]
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180504060003.19618-16-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14 08:57:49 +02:00
Ard Biesheuvel
2c3625cb9f efi/x86: Fold __setup_efi_pci32() and __setup_efi_pci64() into one function
As suggested by Lukas, use his efi_call_proto() and efi_table_attr()
macros to merge __setup_efi_pci32() and __setup_efi_pci64() into a
single function, removing the need to duplicate changes made in
subsequent patches across both.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180504060003.19618-15-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14 08:57:49 +02:00
Ard Biesheuvel
cb0ba79352 efi: Align efi_pci_io_protocol typedefs to type naming convention
In order to use the helper macros that perform type mangling with the
EFI PCI I/O protocol struct typedefs, align their Linux typenames with
the convention we use for definitionns that originate in the UEFI spec,
and add the trailing _t to each.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180504060003.19618-14-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14 08:57:48 +02:00
Ard Biesheuvel
0b3225ab94 efi: Avoid potential crashes, fix the 'struct efi_pci_io_protocol_32' definition for mixed mode
Mixed mode allows a kernel built for x86_64 to interact with 32-bit
EFI firmware, but requires us to define all struct definitions carefully
when it comes to pointer sizes.

'struct efi_pci_io_protocol_32' currently uses a 'void *' for the
'romimage' field, which will be interpreted as a 64-bit field
on such kernels, potentially resulting in bogus memory references
and subsequent crashes.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180504060003.19618-13-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14 08:56:29 +02:00
Dave Hansen
fb43d6cb91 x86/mm: Do not auto-massage page protections
A PTE is constructed from a physical address and a pgprotval_t.
__PAGE_KERNEL, for instance, is a pgprot_t and must be converted
into a pgprotval_t before it can be used to create a PTE.  This is
done implicitly within functions like pfn_pte() by massage_pgprot().

However, this makes it very challenging to set bits (and keep them
set) if your bit is being filtered out by massage_pgprot().

This moves the bit filtering out of pfn_pte() and friends.  For
users of PAGE_KERNEL*, filtering will be done automatically inside
those macros but for users of __PAGE_KERNEL*, they need to do their
own filtering now.

Note that we also just move pfn_pte/pmd/pud() over to check_pgprot()
instead of massage_pgprot().  This way, we still *look* for
unsupported bits and properly warn about them if we find them.  This
might happen if an unfiltered __PAGE_KERNEL* value was passed in,
for instance.

- printk format warning fix from: Arnd Bergmann <arnd@arndb.de>
- boot crash fix from:            Tom Lendacky <thomas.lendacky@amd.com>
- crash bisected by:              Mike Galbraith <efault@gmx.de>

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reported-and-fixed-by: Arnd Bergmann <arnd@arndb.de>
Fixed-by: Tom Lendacky <thomas.lendacky@amd.com>
Bisected-by: Mike Galbraith <efault@gmx.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180406205509.77E1D7F6@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-12 09:04:22 +02:00
Linus Torvalds
bc16d4052f Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The main EFI changes in this cycle were:

   - Fix the apple-properties code (Andy Shevchenko)

   - Add WARN() on arm64 if UEFI Runtime Services corrupt the reserved
     x18 register (Ard Biesheuvel)

   - Use efi_switch_mm() on x86 instead of manipulating %cr3 directly
     (Sai Praneeth)

   - Fix early memremap leak in ESRT code (Ard Biesheuvel)

   - Switch to L"xxx" notation for wide string literals (Ard Biesheuvel)

   - ... plus misc other cleanups and bugfixes"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/efi: Use efi_switch_mm() rather than manually twiddling with %cr3
  x86/efi: Replace efi_pgd with efi_mm.pgd
  efi: Use string literals for efi_char16_t variable initializers
  efi/esrt: Fix handling of early ESRT table mapping
  efi: Use efi_mm in x86 as well as ARM
  efi: Make const array 'apple' static
  efi/apple-properties: Use memremap() instead of ioremap()
  efi: Reorder pr_notice() with add_device_randomness() call
  x86/efi: Replace GFP_ATOMIC with GFP_KERNEL in efi_query_variable_store()
  efi/arm64: Check whether x18 is preserved by runtime services calls
  efi/arm*: Stop printing addresses of virtual mappings
  efi/apple-properties: Remove redundant attribute initialization from unmarshal_key_value_pairs()
  efi/arm*: Only register page tables when they exist
2018-04-02 17:46:37 -07:00
Linus Torvalds
d22fff8141 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar:

 - Extend the memmap= boot parameter syntax to allow the redeclaration
   and dropping of existing ranges, and to support all e820 range types
   (Jan H. Schönherr)

 - Improve the W+X boot time security checks to remove false positive
   warnings on Xen (Jan Beulich)

 - Support booting as Xen PVH guest (Juergen Gross)

 - Improved 5-level paging (LA57) support, in particular it's possible
   now to have a single kernel image for both 4-level and 5-level
   hardware (Kirill A. Shutemov)

 - AMD hardware RAM encryption support (SME/SEV) fixes (Tom Lendacky)

 - Preparatory commits for hardware-encrypted RAM support on Intel CPUs.
   (Kirill A. Shutemov)

 - Improved Intel-MID support (Andy Shevchenko)

 - Show EFI page tables in page_tables debug files (Andy Lutomirski)

 - ... plus misc fixes and smaller cleanups

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits)
  x86/cpu/tme: Fix spelling: "configuation" -> "configuration"
  x86/boot: Fix SEV boot failure from change to __PHYSICAL_MASK_SHIFT
  x86/mm: Update comment in detect_tme() regarding x86_phys_bits
  x86/mm/32: Remove unused node_memmap_size_bytes() & CONFIG_NEED_NODE_MEMMAP_SIZE logic
  x86/mm: Remove pointless checks in vmalloc_fault
  x86/platform/intel-mid: Add special handling for ACPI HW reduced platforms
  ACPI, x86/boot: Introduce the ->reduced_hw_early_init() ACPI callback
  ACPI, x86/boot: Split out acpi_generic_reduce_hw_init() and export
  x86/pconfig: Provide defines and helper to run MKTME_KEY_PROG leaf
  x86/pconfig: Detect PCONFIG targets
  x86/tme: Detect if TME and MKTME is activated by BIOS
  x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G
  x86/boot/compressed/64: Use page table in trampoline memory
  x86/boot/compressed/64: Use stack from trampoline memory
  x86/boot/compressed/64: Make sure we have a 32-bit code segment
  x86/mm: Do not use paravirtualized calls in native_set_p4d()
  kdump, vmcoreinfo: Export pgtable_l5_enabled value
  x86/boot/compressed/64: Prepare new top-level page table for trampoline
  x86/boot/compressed/64: Set up trampoline memory
  x86/boot/compressed/64: Save and restore trampoline memory
  ...
2018-04-02 15:45:30 -07:00
Linus Torvalds
e68b4bad71 Merge branch 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 build updates from Ingo Molnar:
 "The biggest change is the forcing of asm-goto support on x86, which
  effectively increases the GCC minimum supported version to gcc-4.5 (on
  x86)"

* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/build: Don't pass in -D__KERNEL__ multiple times
  x86: Remove FAST_FEATURE_TESTS
  x86: Force asm-goto
  x86/build: Drop superfluous ALIGN from the linker script
2018-04-02 14:37:03 -07:00
Cao jin
d6289f36aa x86/build: Don't pass in -D__KERNEL__ multiple times
Some .<target>.cmd files under arch/x86 are showing two instances of
-D__KERNEL__, like arch/x86/boot/ and arch/x86/realmode/rm/.

__KERNEL__ is already defined in KBUILD_CPPFLAGS in the top Makefile,
so it can be dropped safely.

Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kbuild@vger.kernel.org
Link: http://lkml.kernel.org/r/20180316084944.3997-1-caoj.fnst@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-31 08:02:07 +02:00
Tom Lendacky
07344b15a9 x86/boot: Fix SEV boot failure from change to __PHYSICAL_MASK_SHIFT
In arch/x86/boot/compressed/kaslr_64.c, CONFIG_AMD_MEM_ENCRYPT support was
initially #undef'd to support SME with minimal effort.  When support for
SEV was added, the #undef remained and some minimal support for setting the
encryption bit was added for building identity mapped pagetable entries.

Commit b83ce5ee91 ("x86/mm/64: Make __PHYSICAL_MASK_SHIFT always 52")
changed __PHYSICAL_MASK_SHIFT from 46 to 52 in support of 5-level paging.
This change resulted in SEV guests failing to boot because the encryption
bit was no longer being automatically masked out.  The compressed boot
path now requires sme_me_mask to be defined in order for the pagetable
functions, such as pud_present(), to properly mask out the encryption bit
(currently bit 47) when evaluating pagetable entries.

Add an sme_me_mask variable in arch/x86/boot/compressed/mem_encrypt.S,
which is set when SEV is active, delete the #undef CONFIG_AMD_MEM_ENCRYPT
from arch/x86/boot/compressed/kaslr_64.c and use sme_me_mask when building
the identify mapped pagetable entries.

Fixes: b83ce5ee91 ("x86/mm/64: Make __PHYSICAL_MASK_SHIFT always 52")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20180327220711.8702.55842.stgit@tlendack-t1.amdoffice.net
2018-03-28 10:42:57 +02:00
Ingo Molnar
0bc91d4ba7 Linux 4.16-rc7
-----BEGIN PGP SIGNATURE-----
 
 iQEcBAABAgAGBQJauCZfAAoJEHm+PkMAQRiGWGUH/2rhdQDkoJpYWnjaQkolECG8
 MxpGE7nmIIHxQcbSDdHTGJ8IhVm6Z5wZ7ym/PwCDTT043Y1y341sJrIwL2/nTG6d
 HVidk8hFvgN6QzlzVAHT3ZZMII/V9Zt+VV5SUYLGnPAVuJNHo/6uzWlTU5g+NTFo
 IquFDdQUaGBlkKqby+NoAFnkV1UAIkW0g22cfvPnlO5GMer0gusGyVNvVp7TNj3C
 sqj4Hvt3RMDLMNe9RZ2pFTiOD096n8FWpYftZneUTxFImhRV3Jg5MaaYZm9SI3HW
 tXrv/LChT/F1mi5Pkx6tkT5Hr8WvcrwDMJ4It1kom10RqWAgjxIR3CMm448ileY=
 =YKUG
 -----END PGP SIGNATURE-----

Merge tag 'v4.16-rc7' into x86/mm, to fix up conflict

 Conflicts:
	arch/x86/mm/init_64.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-27 08:43:39 +02:00
Linus Torvalds
d2862360bf Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 and PTI fixes from Ingo Molnar:
 "Misc fixes:

   - fix EFI pagetables freeing

   - fix vsyscall pagetable setting on Xen PV guests

   - remove ancient CONFIG_X86_PPRO_FENCE=y - x86 is TSO again

   - fix two binutils (ld) development version related incompatibilities

   - clean up breakpoint handling

   - fix an x86 self-test"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/entry/64: Don't use IST entry for #BP stack
  x86/efi: Free efi_pgd with free_pages()
  x86/vsyscall/64: Use proper accessor to update P4D entry
  x86/cpu: Remove the CONFIG_X86_PPRO_FENCE=y quirk
  x86/boot/64: Verify alignment of the LOAD segment
  x86/build/64: Force the linker to use 2MB page size
  selftests/x86/ptrace_syscall: Fix for yet more glibc interference
2018-03-25 07:36:02 -10:00
H.J. Lu
c55b8550fa x86/boot/64: Verify alignment of the LOAD segment
Since the x86-64 kernel must be aligned to 2MB, refuse to boot the
kernel if the alignment of the LOAD segment isn't a multiple of 2MB.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/CAMe9rOrR7xSJgUfiCoZLuqWUwymRxXPoGBW38%2BpN%3D9g%2ByKNhZw@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-20 08:03:03 +01:00
Kirill A. Shutemov
194a9749c7 x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G
This patch addresses a shortcoming in current boot process on machines
that supports 5-level paging.

If a bootloader enables 64-bit mode with 4-level paging, we might need to
switch over to 5-level paging. The switching requires the disabling
paging. It works fine if kernel itself is loaded below 4G.

But if the bootloader put the kernel above 4G (not sure if anybody does
this), we would lose control as soon as paging is disabled, because the
code becomes unreachable to the CPU.

This patch implements a trampoline in lower memory to handle this
situation.

We only need the memory for a very short time, until the main kernel
image sets up own page tables.

We go through the trampoline even if we don't have to: if we're already
in 5-level paging mode or if we don't need to switch to it. This way the
trampoline gets tested on every boot.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 11:49:25 +01:00
Kirill A. Shutemov
0a1756bd28 x86/boot/compressed/64: Use page table in trampoline memory
If a bootloader enables 64-bit mode with 4-level paging, we might need to
switch over to 5-level paging. The switching requires the disabling
paging. It works fine if kernel itself is loaded below 4G.

But if the bootloader put the kernel above 4G (i.e. in kexec() case),
we would lose control as soon as paging is disabled, because the code
becomes unreachable to the CPU.

To handle the situation, we need a trampoline in lower memory that would
take care of switching on 5-level paging.

Apart from the trampoline code itself we also need a place to store
top-level page table in lower memory as we don't have a way to load
64-bit values into CR3 in 32-bit mode. We only really need 8 bytes there
as we only use the very first entry of the page table. But we allocate a
whole page anyway.

This patch switches 32-bit code to use page table in trampoline memory.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 11:49:25 +01:00
Kirill A. Shutemov
f7ff53e470 x86/boot/compressed/64: Use stack from trampoline memory
As the first step on using trampoline memory, let's make 32-bit code use
stack there.

Separate stack is required to return back from trampoline and we cannot
user stack from 64-bit mode as it may be above 4G.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 11:49:24 +01:00
Kirill A. Shutemov
7beebaccd5 x86/boot/compressed/64: Make sure we have a 32-bit code segment
When kernel starts in 64-bit mode we inherit the GDT from the bootloader.
It may cause a problem if the GDT doesn't have a 32-bit code segment
where we expect it to be.

Load our own GDT with known segments.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 11:49:24 +01:00
Ard Biesheuvel
36b649760e efi: Use string literals for efi_char16_t variable initializers
Now that we unambiguously build the entire kernel with -fshort-wchar,
it is no longer necessary to open code efi_char16_t[] initializers as
arrays of characters, and we can move to the L"xxx" notation instead.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180312084500.10764-6-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 10:05:02 +01:00
Kirill A. Shutemov
e9d0e6330e x86/boot/compressed/64: Prepare new top-level page table for trampoline
If trampoline code would need to switch between 4- and 5-level paging
modes, we have to use a page table in trampoline memory.

Having it in trampoline memory guarantees that it's below 4G and we can
point CR3 to it from 32-bit trampoline code.

We only use the page table if the desired paging mode doesn't match the
mode we are in. Otherwise the page table is unused and trampoline code
wouldn't touch CR3.

For 4- to 5-level paging transition, we set up current (4-level paging)
CR3 as the first and the only entry in a new top-level page table.

For 5- to 4-level paging transition, copy page table pointed by first
entry in the current top-level page table as our new top-level page
table.

If the page table is used by trampoline we would need to copy it to new
page table outside trampoline and update CR3 before restoring trampoline
memory.

Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-6-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 09:37:26 +01:00
Kirill A. Shutemov
32fcefa2bf x86/boot/compressed/64: Set up trampoline memory
This patch clears up trampoline memory and copies trampoline code in
place. It's not yet used though.

Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 09:37:25 +01:00
Kirill A. Shutemov
fb5268354d x86/boot/compressed/64: Save and restore trampoline memory
The memory area we found for trampoline shouldn't contain anything
useful. But let's preserve the data anyway. Just to be on safe side.

paging_prepare() would save the data into a buffer.

cleanup_trampoline() would restore it back once we are done with the
trampoline.

Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 09:37:25 +01:00
Kirill A. Shutemov
3548e131ec x86/boot/compressed/64: Find a place for 32-bit trampoline
If a bootloader enables 64-bit mode with 4-level paging, we might need to
switch over to 5-level paging. The switching requires the disabling of
paging, which works fine if kernel itself is loaded below 4G.

But if the bootloader puts the kernel above 4G (not sure if anybody does
this), we would lose control as soon as paging is disabled, because the
code becomes unreachable to the CPU.

To handle the situation, we need a trampoline in lower memory that would
take care of switching on 5-level paging.

This patch finds a spot in low memory for a trampoline.

The heuristic is based on code in reserve_bios_regions().

We find the end of low memory based on BIOS and EBDA start addresses.
The trampoline is put just before end of low memory. It's mimic approach
taken to allocate memory for realtime trampoline.

Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 09:37:23 +01:00
Kirill A. Shutemov
a403d79818 x86/boot/compressed/64: Describe the logic behind the LA57 check
The patch explains the LA57 check in more details.

Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 09:29:24 +01:00
Colin Ian King
f779ca740f efi: Make const array 'apple' static
Don't populate the const read-only array 'buf' on the stack but instead
make it static. Makes the object code smaller by 64 bytes:

Before:
   text	   data	    bss	    dec	    hex	filename
   9264	      1	     16	   9281	   2441	arch/x86/boot/compressed/eboot.o

After:
   text	   data	    bss	    dec	    hex	filename
   9200	      1	     16	   9217	   2401	arch/x86/boot/compressed/eboot.o

(GCC version 7.2.0 x86_64)

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180308080020.22828-13-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-09 09:30:35 +01:00
Ingo Molnar
1ea4fe8497 Merge branch 'x86/boot' into x86/mm, to unify branches
Both x86/mm and x86/boot contain 5-level paging related patches,
unify them to have a single tree to work against.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-26 08:48:08 +01:00
Ingo Molnar
3f7df3efeb Linux 4.16-rc3
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAlqTdg8eHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiG10wH/iSt+OKmBdUZSAYv
 ADvfifLynLgugFYNzuijj8/gVt6b0ZIB2/wSYfdPjDErLFogis6wjnxl0lf3sEMB
 g7Oy8SE+pPPQ7587lFkg6Pj53405b6BwCbSkg8PLlwepSGiu0JmGvUYmz753tIeP
 kRIIQk/KrLlxNFixhGWNfQ9k8PqJ0NCgcbj+mTxmFkfIw2FKnBtYz72LR7Eut3Mt
 PJFh4pLKsHKlcjvX8+SehDdLwlEBv/ohDP7S7gRyR+QX1aNZhZAXyHQ0C8/tw8h6
 DnRvlTWp9EGTFxp8bYie5xcWusIcfy1eAA8yiG2kH+Mx7kLa8cmU234bHhUiu9yT
 YJSLoI4=
 =XBoV
 -----END PGP SIGNATURE-----

Merge tag 'v4.16-rc3' into x86/mm, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-26 08:41:15 +01:00
Ingo Molnar
ed7158bae4 treewide/trivial: Remove ';;$' typo noise
On lkml suggestions were made to split up such trivial typo fixes into per subsystem
patches:

  --- a/arch/x86/boot/compressed/eboot.c
  +++ b/arch/x86/boot/compressed/eboot.c
  @@ -439,7 +439,7 @@ setup_uga32(void **uga_handle, unsigned long size, u32 *width, u32 *height)
          struct efi_uga_draw_protocol *uga = NULL, *first_uga;
          efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID;
          unsigned long nr_ugas;
  -       u32 *handles = (u32 *)uga_handle;;
  +       u32 *handles = (u32 *)uga_handle;
          efi_status_t status = EFI_INVALID_PARAMETER;
          int i;

This patch is the result of the following script:

  $ sed -i 's/;;$/;/g' $(git grep -E ';;$'  | grep "\.[ch]:"  | grep -vwE 'for|ia64' | cut -d: -f1 | sort | uniq)

... followed by manual review to make sure it's all good.

Splitting this up is just crazy talk, let's get over with this and just do it.

Reported-by: Pavel Machek <pavel@ucw.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-22 10:59:33 +01:00
Kirill A. Shutemov
39b9552281 x86/mm: Optimize boot-time paging mode switching cost
By this point we have functioning boot-time switching between 4- and
5-level paging mode. But naive approach comes with cost.

Numbers below are for kernel build, allmodconfig, 5 times.

CONFIG_X86_5LEVEL=n:

 Performance counter stats for 'sh -c make -j100 -B -k >/dev/null' (5 runs):

   17308719.892691      task-clock:u (msec)       #   26.772 CPUs utilized            ( +-  0.11% )
                 0      context-switches:u        #    0.000 K/sec
                 0      cpu-migrations:u          #    0.000 K/sec
       331,993,164      page-faults:u             #    0.019 M/sec                    ( +-  0.01% )
43,614,978,867,455      cycles:u                  #    2.520 GHz                      ( +-  0.01% )
39,371,534,575,126      stalled-cycles-frontend:u #   90.27% frontend cycles idle     ( +-  0.09% )
28,363,350,152,428      instructions:u            #    0.65  insn per cycle
                                                  #    1.39  stalled cycles per insn  ( +-  0.00% )
 6,316,784,066,413      branches:u                #  364.948 M/sec                    ( +-  0.00% )
   250,808,144,781      branch-misses:u           #    3.97% of all branches          ( +-  0.01% )

     646.531974142 seconds time elapsed                                          ( +-  1.15% )

CONFIG_X86_5LEVEL=y:

 Performance counter stats for 'sh -c make -j100 -B -k >/dev/null' (5 runs):

   17411536.780625      task-clock:u (msec)       #   26.426 CPUs utilized            ( +-  0.10% )
                 0      context-switches:u        #    0.000 K/sec
                 0      cpu-migrations:u          #    0.000 K/sec
       331,868,663      page-faults:u             #    0.019 M/sec                    ( +-  0.01% )
43,865,909,056,301      cycles:u                  #    2.519 GHz                      ( +-  0.01% )
39,740,130,365,581      stalled-cycles-frontend:u #   90.59% frontend cycles idle     ( +-  0.05% )
28,363,358,997,959      instructions:u            #    0.65  insn per cycle
                                                  #    1.40  stalled cycles per insn  ( +-  0.00% )
 6,316,784,937,460      branches:u                #  362.793 M/sec                    ( +-  0.00% )
   251,531,919,485      branch-misses:u           #    3.98% of all branches          ( +-  0.00% )

     658.886307752 seconds time elapsed                                          ( +-  0.92% )

The patch tries to fix the performance regression by using
cpu_feature_enabled(X86_FEATURE_LA57) instead of pgtable_l5_enabled in
all hot code paths. These will statically patch the target code for
additional performance.

CONFIG_X86_5LEVEL=y + the patch:

 Performance counter stats for 'sh -c make -j100 -B -k >/dev/null' (5 runs):

   17381990.268506      task-clock:u (msec)       #   26.907 CPUs utilized            ( +-  0.19% )
                 0      context-switches:u        #    0.000 K/sec
                 0      cpu-migrations:u          #    0.000 K/sec
       331,862,625      page-faults:u             #    0.019 M/sec                    ( +-  0.01% )
43,697,726,320,051      cycles:u                  #    2.514 GHz                      ( +-  0.03% )
39,480,408,690,401      stalled-cycles-frontend:u #   90.35% frontend cycles idle     ( +-  0.05% )
28,363,394,221,388      instructions:u            #    0.65  insn per cycle
                                                  #    1.39  stalled cycles per insn  ( +-  0.00% )
 6,316,794,985,573      branches:u                #  363.410 M/sec                    ( +-  0.00% )
   251,013,232,547      branch-misses:u           #    3.97% of all branches          ( +-  0.01% )

     645.991174661 seconds time elapsed                                          ( +-  1.19% )

Unfortunately, this approach doesn't help with text size:

  vmlinux.before .text size:	8190319
  vmlinux.after .text size:	8200623

The .text section is increased by about 4k. Not sure if we can do anything
about this.

Signed-off-by: Kirill A. Shuemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180216114948.68868-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-21 10:19:18 +01:00
Kirill A. Shutemov
6657fca06e x86/mm: Allow to boot without LA57 if CONFIG_X86_5LEVEL=y
All pieces of the puzzle are in place and we can now allow to boot with
CONFIG_X86_5LEVEL=y on a machine without LA57 support.

Kernel will detect that LA57 is missing and fold p4d at runtime.

Update the documentation and the Kconfig option description to reflect the
change.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214182542.69302-10-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-16 10:48:49 +01:00
Kirill A. Shutemov
b16e770bfa x86/mm: Initialize 'pgdir_shift' and 'ptrs_per_p4d' at boot-time
Switching between paging modes requires the folding of the p4d page table level
when we only have 4 paging levels, which means we need to adjust 'pgdir_shift'
and 'ptrs_per_p4d' during early boot according to paging mode.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214182542.69302-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-16 10:48:47 +01:00
Kirill A. Shutemov
4c2b4058ab x86/mm: Initialize 'pgtable_l5_enabled' at boot-time
'pgtable_l5_enabled' indicates which paging mode we are using. We need to
initialize it at boot-time according to machine capability.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214182542.69302-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-16 10:48:46 +01:00
Kirill A. Shutemov
c65e774fb3 x86/mm: Make PGDIR_SHIFT and PTRS_PER_P4D variable
For boot-time switching between 4- and 5-level paging we need to be able
to fold p4d page table level at runtime. It requires variable
PGDIR_SHIFT and PTRS_PER_P4D.

The change doesn't affect the kernel image size much:

   text	   data	    bss	    dec	    hex	filename
8628091	4734304	1368064	14730459	 e0c4db	vmlinux.before
8628393	4734340	1368064	14730797	 e0c62d	vmlinux.after

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214111656.88514-7-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-14 13:11:14 +01:00
Kirill A. Shutemov
e626e6bb0d x86/mm: Introduce 'pgtable_l5_enabled'
The new flag would indicate what paging mode we are in.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214111656.88514-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-14 13:11:14 +01:00
Kirill A. Shutemov
4440977be1 x86/boot/compressed/64: Introduce paging_prepare()
Rename l5_paging_required() to paging_prepare() and change the
interface of the function.

This is a preparation for the next patch, which would make the function
also allocate memory for the 32-bit trampoline.

The function now returns a 128-bit structure. RAX would return
trampoline memory address (zero for now) and RDX would indicate if we
need to enable 5-level paging.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
[ Typo fixes and general clarification. ]
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180209142228.21231-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-11 12:36:18 +01:00
Kirill A. Shutemov
7cc4eb1bdd x86/boot/compressed/64: Rename pagetable.c to kaslr_64.c
The name of the file -- pagetable.c -- is misleading: it only contains
helpers used for KASLR in 64-bit mode.

Let's rename the file to reflect its content.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180209142228.21231-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-11 12:36:18 +01:00
Linus Torvalds
ae0cb7be35 Merge branch 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull tpm updates from James Morris:

 - reduce polling delays in tpm_tis

 - support retrieving TPM 2.0 Event Log through EFI before
   ExitBootServices

 - replace tpm-rng.c with a hwrng device managed by the driver for each
   TPM device

 - TPM resource manager synthesizes TPM_RC_COMMAND_CODE response instead
   of returning -EINVAL for unknown TPM commands. This makes user space
   more sound.

 - CLKRUN fixes:

    * Keep #CLKRUN disable through the entier TPM command/response flow

    * Check whether #CLKRUN is enabled before disabling and enabling it
      again because enabling it breaks PS/2 devices on a system where it
      is disabled

* 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  tpm: remove unused variables
  tpm: remove unused data fields from I2C and OF device ID tables
  tpm: only attempt to disable the LPC CLKRUN if is already enabled
  tpm: follow coding style for variable declaration in tpm_tis_core_init()
  tpm: delete the TPM_TIS_CLK_ENABLE flag
  tpm: Update MAINTAINERS for Jason Gunthorpe
  tpm: Keep CLKRUN enabled throughout the duration of transmit_cmd()
  tpm_tis: Move ilb_base_addr to tpm_tis_data
  tpm2-cmd: allow more attempts for selftest execution
  tpm: return a TPM_RC_COMMAND_CODE response if command is not implemented
  tpm: Move Linux RNG connection to hwrng
  tpm: use struct tpm_chip for tpm_chip_find_get()
  tpm: parse TPM event logs based on EFI table
  efi: call get_event_log before ExitBootServices
  tpm: add event log format version
  tpm: rename event log provider files
  tpm: move tpm_eventlog.h outside of drivers folder
  tpm: use tpm_msleep() value as max delay
  tpm: reduce tpm polling delay in tpm_tis_core
  tpm: move wait_for_tpm_stat() to respective driver files
2018-01-31 13:12:31 -08:00
Thiebaud Weksteen
33b6d03469 efi: call get_event_log before ExitBootServices
With TPM 2.0 specification, the event logs may only be accessible by
calling an EFI Boot Service. Modify the EFI stub to copy the log area to
a new Linux-specific EFI configuration table so it remains accessible
once booted.

When calling this service, it is possible to specify the expected format
of the logs: TPM 1.2 (SHA1) or TPM 2.0 ("Crypto Agile"). For now, only the
first format is retrieved.

Signed-off-by: Thiebaud Weksteen <tweek@google.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
2018-01-08 12:58:35 +02:00
Linus Torvalds
5aa90a8458 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 page table isolation updates from Thomas Gleixner:
 "This is the final set of enabling page table isolation on x86:

   - Infrastructure patches for handling the extra page tables.

   - Patches which map the various bits and pieces which are required to
     get in and out of user space into the user space visible page
     tables.

   - The required changes to have CR3 switching in the entry/exit code.

   - Optimizations for the CR3 switching along with documentation how
     the ASID/PCID mechanism works.

   - Updates to dump pagetables to cover the user space page tables for
     W+X scans and extra debugfs files to analyze both the kernel and
     the user space visible page tables

  The whole functionality is compile time controlled via a config switch
  and can be turned on/off on the command line as well"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
  x86/ldt: Make the LDT mapping RO
  x86/mm/dump_pagetables: Allow dumping current pagetables
  x86/mm/dump_pagetables: Check user space page table for WX pages
  x86/mm/dump_pagetables: Add page table directory to the debugfs VFS hierarchy
  x86/mm/pti: Add Kconfig
  x86/dumpstack: Indicate in Oops whether PTI is configured and enabled
  x86/mm: Clarify the whole ASID/kernel PCID/user PCID naming
  x86/mm: Use INVPCID for __native_flush_tlb_single()
  x86/mm: Optimize RESTORE_CR3
  x86/mm: Use/Fix PCID to optimize user/kernel switches
  x86/mm: Abstract switching CR3
  x86/mm: Allow flushing for future ASID switches
  x86/pti: Map the vsyscall page if needed
  x86/pti: Put the LDT in its own PGD if PTI is on
  x86/mm/64: Make a full PGD-entry size hole in the memory map
  x86/events/intel/ds: Map debug buffers in cpu_entry_area
  x86/cpu_entry_area: Add debugstore entries to cpu_entry_area
  x86/mm/pti: Map ESPFIX into user space
  x86/mm/pti: Share entry text PMD
  x86/entry: Align entry text section to PMD boundary
  ...
2017-12-29 17:02:49 -08:00
Thomas Gleixner
aa8c6248f8 x86/mm/pti: Add infrastructure for page table isolation
Add the initial files for kernel page table isolation, with a minimal init
function and the boot time detection for this misfeature.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-23 21:12:59 +01:00
Kirill A. Shutemov
6d7e0ba2d2 x86/boot/compressed/64: Print error if 5-level paging is not supported
If the machine does not support the paging mode for which the kernel was
compiled, the boot process cannot continue.

It's not possible to let the kernel detect the mismatch as it does not even
reach the point where cpu features can be evaluted due to a triple fault in
the KASLR setup.

Instead of instantaneous silent reboot, emit an error message which gives
the user the information why the boot fails.

Fixes: 77ef56e4f0 ("x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y")
Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: linux-mm@kvack.org
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20171204124059.63515-3-kirill.shutemov@linux.intel.com
2017-12-07 10:36:26 +01:00
Kirill A. Shutemov
08529078d8 x86/boot/compressed/64: Detect and handle 5-level paging at boot-time
Prerequisite for fixing the current problem of instantaneous reboots when a
5-level paging kernel is booted on 4-level paging hardware.

At the same time this change prepares the decompression code to boot-time
switching between 4- and 5-level paging.

[ tglx: Folded the GCC < 5 fix. ]

Fixes: 77ef56e4f0 ("x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: linux-mm@kvack.org
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20171204124059.63515-2-kirill.shutemov@linux.intel.com
2017-12-07 10:34:39 +01:00
Chao Fan
69550d41ff x86/boot/KASLR: Remove unused variable
There are two variables "rc" in mem_avoid_memmap. One at the top of the
function and another one inside the while() loop. Drop the outer one as it
is unused. Cleanup some whitespace damage while at it.

Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gregkh@linuxfoundation.org
Cc: n-horiguchi@ah.jp.nec.com
Cc: keescook@chromium.org
Link: https://lkml.kernel.org/r/20171123090847.15293-1-fanc.fnst@cn.fujitsu.com
2017-11-23 20:17:59 +01:00
Linus Torvalds
6a9f70b0a5 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "Three smaller changes:

   - clang fix

   - boot message beautification

   - unnecessary header inclusion removal"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Disable Clang warnings about GNU extensions
  x86/boot: Remove unnecessary #include <generated/utsrelease.h>
  x86/boot: Spell out "boot CPU" for BP
2017-11-13 16:32:30 -08:00
Tom Lendacky
1958b5fc40 x86/boot: Add early boot support when running with SEV active
Early in the boot process, add checks to determine if the kernel is
running with Secure Encrypted Virtualization (SEV) active.

Checking for SEV requires checking that the kernel is running under a
hypervisor (CPUID 0x00000001, bit 31), that the SEV feature is available
(CPUID 0x8000001f, bit 1) and then checking a non-interceptable SEV MSR
(0xc0010131, bit 0).

This check is required so that during early compressed kernel booting the
pagetables (both the boot pagetables and KASLR pagetables (if enabled) are
updated to include the encryption mask so that when the kernel is
decompressed into encrypted memory, it can boot properly.

After the kernel is decompressed and continues booting the same logic is
used to check if SEV is active and set a flag indicating so.  This allows
to distinguish between SME and SEV, each of which have unique differences
in how certain things are handled: e.g. DMA (always bounce buffered with
SEV) or EFI tables (always access decrypted with SME).

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: kvm@vger.kernel.org
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Link: https://lkml.kernel.org/r/20171020143059.3291-13-brijesh.singh@amd.com
2017-11-07 15:35:58 +01:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Matthias Kaehlcke
6c3b56b197 x86/boot: Disable Clang warnings about GNU extensions
The kernel makes use of several GCC extensions, disable Clang warnings
about that in the boot code, as we already do for the rest of the kernel.

This suppresses the following warning when building with clang:

  ./include/linux/cgroup-defs.h:391:16: warning: field 'cgrp' with variable sized type 'struct cgroup' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end]
        struct cgroup cgrp;

Reported-by: Nick Desaulniers <nick.desaulniers@gmail.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171030194351.122090-1-mka@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-31 10:54:30 +01:00
Linus Torvalds
f92e3da18b Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Transparently fall back to other poweroff method(s) if EFI poweroff
     fails (and returns)

   - Use separate PE/COFF section headers for the RX and RW parts of the
     ARM stub loader so that the firmware can use strict mapping
     permissions

   - Add support for requesting the firmware to wipe RAM at warm reboot

   - Increase the size of the random seed obtained from UEFI so CRNG
     fast init can complete earlier

   - Update the EFI framebuffer address if it points to a BAR that gets
     moved by the PCI resource allocation code

   - Enable "reset attack mitigation" of TPM environments: this is
     enabled if the kernel is configured with
     CONFIG_RESET_ATTACK_MITIGATION=y.

   - Clang related fixes

   - Misc cleanups, constification, refactoring, etc"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/bgrt: Use efi_mem_type()
  efi: Move efi_mem_type() to common code
  efi/reboot: Make function pointer orig_pm_power_off static
  efi/random: Increase size of firmware supplied randomness
  efi/libstub: Enable reset attack mitigation
  firmware/efi/esrt: Constify attribute_group structures
  firmware/efi: Constify attribute_group structures
  firmware/dcdbas: Constify attribute_group structures
  arm/efi: Split zImage code and data into separate PE/COFF sections
  arm/efi: Replace open coded constants with symbolic ones
  arm/efi: Remove pointless dummy .reloc section
  arm/efi: Remove forbidden values from the PE/COFF header
  drivers/fbdev/efifb: Allow BAR to be moved instead of claiming it
  efi/reboot: Fall back to original power-off method if EFI_RESET_SHUTDOWN returns
  efi/arm/arm64: Add missing assignment of efi.config_table
  efi/libstub/arm64: Set -fpie when building the EFI stub
  efi/libstub/arm64: Force 'hidden' visibility for section markers
  efi/libstub/arm64: Use hidden attribute for struct screen_info reference
  efi/arm: Don't mark ACPI reclaim memory as MEMBLOCK_NOMAP
2017-09-07 09:42:35 -07:00
Linus Torvalds
24e700e291 Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 apic updates from Thomas Gleixner:
 "This update provides:

   - Cleanup of the IDT management including the removal of the extra
     tracing IDT. A first step to cleanup the vector management code.

   - The removal of the paravirt op adjust_exception_frame. This is a
     XEN specific issue, but merged through this branch to avoid nasty
     merge collisions

   - Prevent dmesg spam about the TSC DEADLINE bug, when the CPU has
     disabled the TSC DEADLINE timer in CPUID.

   - Adjust a debug message in the ioapic code to print out the
     information correctly"

* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  x86/idt: Fix the X86_TRAP_BP gate
  x86/xen: Get rid of paravirt op adjust_exception_frame
  x86/eisa: Add missing include
  x86/idt: Remove superfluous ALIGNment
  x86/apic: Silence "FW_BUG TSC_DEADLINE disabled due to Errata" on CPUs without the feature
  x86/idt: Remove the tracing IDT leftovers
  x86/idt: Hide set_intr_gate()
  x86/idt: Simplify alloc_intr_gate()
  x86/idt: Deinline setup functions
  x86/idt: Remove unused functions/inlines
  x86/idt: Move interrupt gate initialization to IDT code
  x86/idt: Move APIC gate initialization to tables
  x86/idt: Move regular trap init to tables
  x86/idt: Move IST stack based traps to table init
  x86/idt: Move debug stack init to table based
  x86/idt: Switch early trap init to IDT tables
  x86/idt: Prepare for table based init
  x86/idt: Move early IDT setup out of 32-bit asm
  x86/idt: Move early IDT handler setup to IDT code
  x86/idt: Consolidate IDT invalidation
  ...
2017-09-04 17:43:56 -07:00
Linus Torvalds
b1b6f83ac9 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm changes from Ingo Molnar:
 "PCID support, 5-level paging support, Secure Memory Encryption support

  The main changes in this cycle are support for three new, complex
  hardware features of x86 CPUs:

   - Add 5-level paging support, which is a new hardware feature on
     upcoming Intel CPUs allowing up to 128 PB of virtual address space
     and 4 PB of physical RAM space - a 512-fold increase over the old
     limits. (Supercomputers of the future forecasting hurricanes on an
     ever warming planet can certainly make good use of more RAM.)

     Many of the necessary changes went upstream in previous cycles,
     v4.14 is the first kernel that can enable 5-level paging.

     This feature is activated via CONFIG_X86_5LEVEL=y - disabled by
     default.

     (By Kirill A. Shutemov)

   - Add 'encrypted memory' support, which is a new hardware feature on
     upcoming AMD CPUs ('Secure Memory Encryption', SME) allowing system
     RAM to be encrypted and decrypted (mostly) transparently by the
     CPU, with a little help from the kernel to transition to/from
     encrypted RAM. Such RAM should be more secure against various
     attacks like RAM access via the memory bus and should make the
     radio signature of memory bus traffic harder to intercept (and
     decrypt) as well.

     This feature is activated via CONFIG_AMD_MEM_ENCRYPT=y - disabled
     by default.

     (By Tom Lendacky)

   - Enable PCID optimized TLB flushing on newer Intel CPUs: PCID is a
     hardware feature that attaches an address space tag to TLB entries
     and thus allows to skip TLB flushing in many cases, even if we
     switch mm's.

     (By Andy Lutomirski)

  All three of these features were in the works for a long time, and
  it's coincidence of the three independent development paths that they
  are all enabled in v4.14 at once"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (65 commits)
  x86/mm: Enable RCU based page table freeing (CONFIG_HAVE_RCU_TABLE_FREE=y)
  x86/mm: Use pr_cont() in dump_pagetable()
  x86/mm: Fix SME encryption stack ptr handling
  kvm/x86: Avoid clearing the C-bit in rsvd_bits()
  x86/CPU: Align CR3 defines
  x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages
  acpi, x86/mm: Remove encryption mask from ACPI page protection type
  x86/mm, kexec: Fix memory corruption with SME on successive kexecs
  x86/mm/pkeys: Fix typo in Documentation/x86/protection-keys.txt
  x86/mm/dump_pagetables: Speed up page tables dump for CONFIG_KASAN=y
  x86/mm: Implement PCID based optimization: try to preserve old TLB entries using PCID
  x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y
  x86/mm: Allow userspace have mappings above 47-bit
  x86/mm: Prepare to expose larger address space to userspace
  x86/mpx: Do not allow MPX if we have mappings above 47-bit
  x86/mm: Rename tasksize_32bit/64bit to task_size_32bit/64bit()
  x86/xen: Redefine XEN_ELFNOTE_INIT_P2M using PUD_SIZE * PTRS_PER_PUD
  x86/mm/dump_pagetables: Fix printout of p4d level
  x86/mm/dump_pagetables: Generalize address normalization
  x86/boot: Fix memremap() related build failure
  ...
2017-09-04 12:21:28 -07:00
Linus Torvalds
45153920c7 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "The main changes are KASL related fixes and cleanups: in particular we
  now exclude certain physical memory ranges as KASLR randomization
  targets that have proven to be unreliable (early-)RAM on some firmware
  versions"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/KASLR: Work around firmware bugs by excluding EFI_BOOT_SERVICES_* and EFI_LOADER_* from KASLR's choice
  x86/boot/KASLR: Prefer mirrored memory regions for the kernel physical address
  efi: Introduce efi_early_memdesc_ptr to get pointer to memmap descriptor
  x86/boot/KASLR: Rename process_e820_entry() into process_mem_region()
  x86/boot/KASLR: Switch to pass struct mem_vector to process_e820_entry()
  x86/boot/KASLR: Wrap e820 entries walking code into new function process_e820_entries()
2017-09-04 10:51:02 -07:00
Linus Torvalds
b0c79f49c3 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:

 - Introduce the ORC unwinder, which can be enabled via
   CONFIG_ORC_UNWINDER=y.

   The ORC unwinder is a lightweight, Linux kernel specific debuginfo
   implementation, which aims to be DWARF done right for unwinding.
   Objtool is used to generate the ORC unwinder tables during build, so
   the data format is flexible and kernel internal: there's no
   dependency on debuginfo created by an external toolchain.

   The ORC unwinder is almost two orders of magnitude faster than the
   (out of tree) DWARF unwinder - which is important for perf call graph
   profiling. It is also significantly simpler and is coded defensively:
   there has not been a single ORC related kernel crash so far, even
   with early versions. (knock on wood!)

   But the main advantage is that enabling the ORC unwinder allows
   CONFIG_FRAME_POINTERS to be turned off - which speeds up the kernel
   measurably:

   With frame pointers disabled, GCC does not have to add frame pointer
   instrumentation code to every function in the kernel. The kernel's
   .text size decreases by about 3.2%, resulting in better cache
   utilization and fewer instructions executed, resulting in a broad
   kernel-wide speedup. Average speedup of system calls should be
   roughly in the 1-3% range - measurements by Mel Gorman [1] have shown
   a speedup of 5-10% for some function execution intense workloads.

   The main cost of the unwinder is that the unwinder data has to be
   stored in RAM: the memory cost is 2-4MB of RAM, depending on kernel
   config - which is a modest cost on modern x86 systems.

   Given how young the ORC unwinder code is it's not enabled by default
   - but given the performance advantages the plan is to eventually make
   it the default unwinder on x86.

   See Documentation/x86/orc-unwinder.txt for more details.

 - Remove lguest support: its intended role was that of a temporary
   proof of concept for virtualization, plus its removal will enable the
   reduction (removal) of the paravirt API as well, so Rusty agreed to
   its removal. (Juergen Gross)

 - Clean up and fix FSGS related functionality (Andy Lutomirski)

 - Clean up IO access APIs (Andy Shevchenko)

 - Enhance the symbol namespace (Jiri Slaby)

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits)
  objtool: Handle GCC stack pointer adjustment bug
  x86/entry/64: Use ENTRY() instead of ALIGN+GLOBAL for stub32_clone()
  x86/fpu/math-emu: Add ENDPROC to functions
  x86/boot/64: Extract efi_pe_entry() from startup_64()
  x86/boot/32: Extract efi_pe_entry() from startup_32()
  x86/lguest: Remove lguest support
  x86/paravirt/xen: Remove xen_patch()
  objtool: Fix objtool fallthrough detection with function padding
  x86/xen/64: Fix the reported SS and CS in SYSCALL
  objtool: Track DRAP separately from callee-saved registers
  objtool: Fix validate_branch() return codes
  x86: Clarify/fix no-op barriers for text_poke_bp()
  x86/switch_to/64: Rewrite FS/GS switching yet again to fix AMD CPUs
  selftests/x86/fsgsbase: Test selectors 1, 2, and 3
  x86/fsgsbase/64: Report FSBASE and GSBASE correctly in core dumps
  x86/fsgsbase/64: Fully initialize FS and GS state in start_thread_common
  x86/asm: Fix UNWIND_HINT_REGS macro for older binutils
  x86/asm/32: Fix regs_get_register() on segment registers
  x86/xen/64: Rearrange the SYSCALL entries
  x86/asm/32: Remove a bunch of '& 0xffff' from pt_regs segment reads
  ...
2017-09-04 09:52:57 -07:00
Naoya Horiguchi
0982adc746 x86/boot/KASLR: Work around firmware bugs by excluding EFI_BOOT_SERVICES_* and EFI_LOADER_* from KASLR's choice
There's a potential bug in how we select the KASLR kernel address n
the early boot code.

The KASLR boot code currently chooses the kernel image's physical memory
location from E820_TYPE_RAM regions by walking over all e820 entries.

E820_TYPE_RAM includes EFI_BOOT_SERVICES_CODE and EFI_BOOT_SERVICES_DATA
as well, so those regions can end up hosting the kernel image. According to
the UEFI spec, all memory regions marked as EfiBootServicesCode and
EfiBootServicesData are available as free memory after the first call
to ExitBootServices(). I.e. so such regions should be usable for the
kernel, per spec.

In real life however, we have workarounds for broken x86 firmware,
where we keep such regions reserved until SetVirtualAddressMap() is done.

See the following code in should_map_region():

	static bool should_map_region(efi_memory_desc_t *md)
	{
		...
		/*
		 * Map boot services regions as a workaround for buggy
		 * firmware that accesses them even when they shouldn't.
		 *
		 * See efi_{reserve,free}_boot_services().
		 */
		if (md->type =3D=3D EFI_BOOT_SERVICES_CODE ||
			md->type =3D=3D EFI_BOOT_SERVICES_DATA)
				return false;

This workaround suppressed a boot crash, but potential issues still
remain because no one prevents the regions from overlapping with kernel
image by KASLR.

So let's make sure that EFI_BOOT_SERVICES_{CODE|DATA} regions are never
chosen as kernel memory for the workaround to work fine.

Furthermore, EFI_LOADER_{CODE|DATA} regions are also excluded because
they can be used after ExitBootServices() as defined in EFI spec.

As a result, we choose kernel address only from EFI_CONVENTIONAL_MEMORY
which is the only memory type we know to be safely free.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Junichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Link: http://lkml.kernel.org/r/20170828074444.GC23181@hori1.linux.bs1.fc.nec.co.jp
[ Rewrote/fixed/clarified the changelog and the in code comments. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-31 12:00:35 +02:00
Jan H. Schönherr
fb1cc2f916 x86/boot: Prevent faulty bootparams.screeninfo from causing harm
If a zero for the number of lines manages to slip through, scroll()
may underflow some offset calculations, causing accesses outside the
video memory.

Make the check in __putstr() more pessimistic to prevent that.

Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1503858223-14983-1-git-send-email-jschoenh@amazon.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 13:32:50 +02:00
Jiri Slaby
9e085cefc6 x86/boot/64: Extract efi_pe_entry() from startup_64()
Similarly to the 32-bit code, efi_pe_entry body() is somehow squashed into
startup_64().

In the old days, we forced startup_64() to start at offset 0x200 and efi_pe_entry()
to start at 0x210. But this requirement was removed long time ago, in:

  99f857db88 ("x86, build: Dynamically find entry points in compressed startup code")

The way it is now makes the code less readable and illogical. Given
we can now safely extract the inlined efi_pe_entry() body from
startup_64() into a separate function, we do so.

We also annotate the function appropriatelly by ENTRY+ENDPROC.

ABI offsets are preserved:

  0000000000000000 T startup_32
  0000000000000200 T startup_64
  0000000000000390 T efi64_stub_entry

On the top-level, it looked like:

	.org 0x200
	ENTRY(startup_64)
	#ifdef CONFIG_EFI_STUB		; start of inlined
		jmp     preferred_addr
	GLOBAL(efi_pe_entry)
		... ; a lot of assembly (efi_pe_entry)
		leaq    preferred_addr(%rax), %rax
		jmp     *%rax
	preferred_addr:
	#endif				; end of inlined
		... ; a lot of assembly (startup_64)
	ENDPROC(startup_64)

And it is now converted into:

	.org 0x200
	ENTRY(startup_64)
		... ; a lot of assembly (startup_64)
	ENDPROC(startup_64)

	#ifdef CONFIG_EFI_STUB
	ENTRY(efi_pe_entry)
		... ; a lot of assembly (efi_pe_entry)
		leaq    startup_64(%rax), %rax
		jmp     *%rax
	ENDPROC(efi_pe_entry)
	#endif

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: ard.biesheuvel@linaro.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170824073327.4129-2-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 13:23:29 +02:00
Jiri Slaby
f4dee0bb65 x86/boot/32: Extract efi_pe_entry() from startup_32()
The efi_pe_entry() body is somehow squashed into startup_32(). In the old days,
we forced startup_32() to start at offset 0x00 and efi_pe_entry() to start
at 0x10.

But this requirement was removed long time ago, in:

  99f857db88 ("x86, build: Dynamically find entry points in compressed startup code")

The way it is now makes the code less readable and illogical. Given
we can now safely extract the inlined efi_pe_entry() body from
startup_32() into a separate function, we do so and we separate it to two
functions as they are marked already: efi_pe_entry() + efi32_stub_entry().

We also annotate the functions appropriatelly by ENTRY+ENDPROC.

ABI offset is preserved:

  0000   128 FUNC    GLOBAL DEFAULT    6 startup_32
  0080    60 FUNC    GLOBAL DEFAULT    6 efi_pe_entry
  00bc    68 FUNC    GLOBAL DEFAULT    6 efi32_stub_entry

On the top-level, it looked like this:

	ENTRY(startup_32)
	#ifdef CONFIG_EFI_STUB		; start of inlined
		jmp     preferred_addr
	ENTRY(efi_pe_entry)
		... ; a lot of assembly (efi_pe_entry)
	ENTRY(efi32_stub_entry)
		... ; a lot of assembly (efi32_stub_entry)
		leal    preferred_addr(%eax), %eax
		jmp     *%eax
	preferred_addr:
	#endif				; end of inlined
		... ; a lot of assembly (startup_32)
	ENDPROC(startup_32)

And it is now converted into:

	ENTRY(startup_32)
		... ; a lot of assembly (startup_32)
	ENDPROC(startup_32)

	#ifdef CONFIG_EFI_STUB
	ENTRY(efi_pe_entry)
		... ; a lot of assembly (efi_pe_entry)
	ENDPROC(efi_pe_entry)

	ENTRY(efi32_stub_entry)
		... ; a lot of assembly (efi32_stub_entry)
		leal    startup_32(%eax), %eax
		jmp     *%eax
	ENDPROC(efi32_stub_entry)
	#endif

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: ard.biesheuvel@linaro.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170824073327.4129-1-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 13:23:29 +02:00
Thomas Gleixner
64b163fab6 x86/idt: Unify gate_struct handling for 32/64-bit kernels
The first 32 bits of gate struct are the same for 32 and 64 bit kernels.

The 32-bit version uses desc_struct and no designated data structure,
so we need different accessors for 32 and 64 bit kernels.

Aside of that the macros which are necessary to build the 32-bit
gate descriptor are horrible to read.

Unify the gate structs and switch all code fiddling with it over.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.861974317@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:24 +02:00
Matthew Garrett
ccc829ba36 efi/libstub: Enable reset attack mitigation
If a machine is reset while secrets are present in RAM, it may be
possible for code executed after the reboot to extract those secrets
from untouched memory. The Trusted Computing Group specified a mechanism
for requesting that the firmware clear all RAM on reset before booting
another OS. This is done by setting the MemoryOverwriteRequestControl
variable at startup. If userspace can ensure that all secrets are
removed as part of a controlled shutdown, it can reset this variable to
0 before triggering a hardware reboot.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825155019.6740-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-26 09:20:33 +02:00
Ingo Molnar
413d63d71b Merge branch 'linus' into x86/mm to pick up fixes and to fix conflicts
Conflicts:
	arch/x86/kernel/head64.c
	arch/x86/mm/mmap.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-26 09:19:13 +02:00
Baoquan He
c05cd79750 x86/boot/KASLR: Prefer mirrored memory regions for the kernel physical address
Currently KASLR will parse all e820 entries of RAM type and add all
candidate positions into the slots array. After that we choose one slot
randomly as the new position which the kernel will be decompressed into
and run at.

On systems with EFI enabled, e820 memory regions are coming from EFI
memory regions by combining adjacent regions.

These EFI memory regions have various attributes, and the "mirrored"
attribute is one of them. The physical memory region whose descriptors
in EFI memory map has EFI_MEMORY_MORE_RELIABLE attribute (bit: 16) are
mirrored. The address range mirroring feature of the kernel arranges such
mirrored regions into normal zones and other regions into movable zones.

With the mirroring feature enabled, the code and data of the kernel can only
be located in the more reliable mirrored regions. However, the current KASLR
code doesn't check EFI memory entries, and could choose a new kernel position
in non-mirrored regions. This will break the intended functionality of the
address range mirroring feature.

To fix this, if EFI is detected, iterate EFI memory map and pick the mirrored
region to process for adding candidate of randomization slot. If EFI is disabled
or no mirrored region found, still process the e820 memory map.

Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: ard.biesheuvel@linaro.org
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: keescook@chromium.org
Cc: linux-efi@vger.kernel.org
Cc: matt@codeblueprint.co.uk
Cc: n-horiguchi@ah.jp.nec.com
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/1502722464-20614-3-git-send-email-bhe@redhat.com
[ Rewrote most of the text. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-17 10:51:35 +02:00
Baoquan He
02e43c2dcd efi: Introduce efi_early_memdesc_ptr to get pointer to memmap descriptor
The existing map iteration helper for_each_efi_memory_desc_in_map can
only be used after the kernel initializes the EFI subsystem to set up
struct efi_memory_map.

Before that we also need iterate map descriptors which are stored in several
intermediate structures, like struct efi_boot_memmap for arch independent
usage and struct efi_info for x86 arch only.

Introduce efi_early_memdesc_ptr() to get pointer to a map descriptor, and
replace several places where that primitive is open coded.

Signed-off-by: Baoquan He <bhe@redhat.com>
[ Various improvements to the text. ]
Acked-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: ard.biesheuvel@linaro.org
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: keescook@chromium.org
Cc: linux-efi@vger.kernel.org
Cc: n-horiguchi@ah.jp.nec.com
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/20170816134651.GF21273@x1
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-17 10:50:57 +02:00
Ingo Molnar
2257e268b1 Merge branch 'linus' into x86/boot, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-17 10:50:48 +02:00
Matthias Kaehlcke
20c6c18904 x86/boot: Disable the address-of-packed-member compiler warning
The clang warning 'address-of-packed-member' is disabled for the general
kernel code, also disable it for the x86 boot code.

This suppresses a bunch of warnings like this when building with clang:

./arch/x86/include/asm/processor.h:535:30: warning: taking address of
  packed member 'sp0' of class or structure 'x86_hw_tss' may result in an
  unaligned pointer value [-Waddress-of-packed-member]
    return this_cpu_read_stable(cpu_tss.x86_tss.sp0);
                                ^~~~~~~~~~~~~~~~~~~
./arch/x86/include/asm/percpu.h:391:59: note: expanded from macro
  'this_cpu_read_stable'
    #define this_cpu_read_stable(var)       percpu_stable_op("mov", var)
                                                                    ^~~
./arch/x86/include/asm/percpu.h:228:16: note: expanded from macro
  'percpu_stable_op'
    : "p" (&(var)));
             ^~~

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Cc: Doug Anderson <dianders@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170725215053.135586-1-mka@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-28 08:39:08 +02:00
Tom Lendacky
21729f81ce x86/mm: Provide general kernel support for memory encryption
Changes to the existing page table macros will allow the SME support to
be enabled in a simple fashion with minimal changes to files that use these
macros.  Since the memory encryption mask will now be part of the regular
pagetable macros, we introduce two new macros (_PAGE_TABLE_NOENC and
_KERNPG_TABLE_NOENC) to allow for early pagetable creation/initialization
without the encryption mask before SME becomes active.  Two new pgprot()
macros are defined to allow setting or clearing the page encryption mask.

The FIXMAP_PAGE_NOCACHE define is introduced for use with MMIO.  SME does
not support encryption for MMIO areas so this define removes the encryption
mask from the page attribute.

Two new macros are introduced (__sme_pa() / __sme_pa_nodebug()) to allow
creating a physical address with the encryption mask.  These are used when
working with the cr3 register so that the PGD can be encrypted. The current
__va() macro is updated so that the virtual address is generated based off
of the physical address without the encryption mask thus allowing the same
virtual address to be generated regardless of whether encryption is enabled
for that physical location or not.

Also, an early initialization function is added for SME.  If SME is active,
this function:

 - Updates the early_pmd_flags so that early page faults create mappings
   with the encryption mask.

 - Updates the __supported_pte_mask to include the encryption mask.

 - Updates the protection_map entries to include the encryption mask so
   that user-space allocations will automatically have the encryption mask
   applied.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Toshimitsu Kani <toshi.kani@hpe.com>
Cc: kasan-dev@googlegroups.com
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/b36e952c4c39767ae7f0a41cf5345adf27438480.1500319216.git.thomas.lendacky@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:38:00 +02:00
Baoquan He
27aac20574 x86/boot/KASLR: Rename process_e820_entry() into process_mem_region()
Now process_e820_entry() is not limited to e820 entry processing, rename
it to process_mem_region(). And adjust the code comment accordingly.

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: matt@codeblueprint.co.uk
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/1499603862-11516-4-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:11:12 +02:00
Baoquan He
87891b01b5 x86/boot/KASLR: Switch to pass struct mem_vector to process_e820_entry()
This makes process_e820_entry() be able to process any kind of memory
region.

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: matt@codeblueprint.co.uk
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/1499603862-11516-3-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:11:11 +02:00
Baoquan He
f62995c92a x86/boot/KASLR: Wrap e820 entries walking code into new function process_e820_entries()
The original function process_e820_entry() only takes care of each
e820 entry passed.

And move the E820_TYPE_RAM checking logic into process_e820_entries().

And remove the redundent local variable 'addr' definition in
find_random_phys_addr().

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: matt@codeblueprint.co.uk
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/1499603862-11516-2-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:11:11 +02:00
Daniel Micay
6974f0c455 include/linux/string.h: add the option of fortified string.h functions
This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time.  Unlike glibc,
it covers buffer reads in addition to writes.

GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation.  They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks.  Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.

This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code.  There will likely be issues caught in
regular use at runtime too.

Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:

* Some of the fortified string functions (strncpy, strcat), don't yet
  place a limit on reads from the source based on __builtin_object_size of
  the source buffer.

* Extending coverage to more string functions like strlcat.

* It should be possible to optionally use __builtin_object_size(x, 1) for
  some functions (C strings) to detect intra-object overflows (like
  glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
  approach to avoid likely compatibility issues.

* The compile-time checks should be made available via a separate config
  option which can be enabled by default (or always enabled) once enough
  time has passed to get the issues it catches fixed.

Kees said:
 "This is great to have. While it was out-of-tree code, it would have
  blocked at least CVE-2016-3858 from being exploitable (improper size
  argument to strlcpy()). I've sent a number of fixes for
  out-of-bounds-reads that this detected upstream already"

[arnd@arndb.de: x86: fix fortified memcpy]
  Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
  Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:26:03 -07:00
Linus Torvalds
7a69f9c60b Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Continued work to add support for 5-level paging provided by future
     Intel CPUs. In particular we switch the x86 GUP code to the generic
     implementation. (Kirill A. Shutemov)

   - Continued work to add PCID CPU support to native kernels as well.
     In this round most of the focus is on reworking/refreshing the TLB
     flush infrastructure for the upcoming PCID changes. (Andy
     Lutomirski)"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
  x86/mm: Delete a big outdated comment about TLB flushing
  x86/mm: Don't reenter flush_tlb_func_common()
  x86/KASLR: Fix detection 32/64 bit bootloaders for 5-level paging
  x86/ftrace: Exclude functions in head64.c from function-tracing
  x86/mmap, ASLR: Do not treat unlimited-stack tasks as legacy mmap
  x86/mm: Remove reset_lazy_tlbstate()
  x86/ldt: Simplify the LDT switching logic
  x86/boot/64: Put __startup_64() into .head.text
  x86/mm: Add support for 5-level paging for KASLR
  x86/mm: Make kernel_physical_mapping_init() support 5-level paging
  x86/mm: Add sync_global_pgds() for configuration with 5-level paging
  x86/boot/64: Add support of additional page table level during early boot
  x86/boot/64: Rename init_level4_pgt and early_level4_pgt
  x86/boot/64: Rewrite startup_64() in C
  x86/boot/compressed: Enable 5-level paging during decompression stage
  x86/boot/efi: Define __KERNEL32_CS GDT on 64-bit configurations
  x86/boot/efi: Fix __KERNEL_CS definition of GDT entry on 64-bit configurations
  x86/boot/efi: Cleanup initialization of GDT entries
  x86/asm: Fix comment in return_from_SYSCALL_64()
  x86/mm/gup: Switch GUP to the generic get_user_page_fast() implementation
  ...
2017-07-03 14:45:09 -07:00
Linus Torvalds
25e09ca524 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "The main changes in this cycle were KASLR improvements for rare
  environments with special boot options, by Baoquan He. Also misc
  smaller changes/cleanups"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/debug: Extend the lower bound of crash kernel low reservations
  x86/boot: Remove unused copy_*_gs() functions
  x86/KASLR: Use the right memcpy() implementation
  Documentation/kernel-parameters.txt: Update 'memmap=' boot option description
  x86/KASLR: Handle the memory limit specified by the 'memmap=' and 'mem=' boot options
  x86/KASLR: Parse all 'memmap=' boot option entries
2017-07-03 13:40:38 -07:00
Kirill A. Shutemov
a24261d70e x86/KASLR: Fix detection 32/64 bit bootloaders for 5-level paging
KASLR uses hack to detect whether we booted via startup_32() or
startup_64(): it checks what is loaded into cr3 and compares it to
_pgtables. _pgtables is the array of page tables where early code
allocates page table from.

KASLR expects cr3 to point to _pgtables if we booted via startup_32(), but
that's not true if we booted with 5-level paging enabled. In this case top
level page table is allocated separately and only the first p4d page table
is allocated from the array.

Let's modify the check to cover both 4- and 5-level paging cases.

The patch also renames 'level4p' to 'top_level_pgt' as it now can hold
page table for 4th or 5th level, depending on configuration.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170628121730.43079-1-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-30 08:56:53 +02:00
Baoquan He
8eabf42ae5 x86/boot/KASLR: Fix kexec crash due to 'virt_addr' calculation bug
Kernel text KASLR is separated into physical address and virtual
address randomization. And for virtual address randomization, we
only randomiza to get an offset between 16M and KERNEL_IMAGE_SIZE.
So the initial value of 'virt_addr' should be LOAD_PHYSICAL_ADDR,
but not the original kernel loading address 'output'.

The bug will cause kernel boot failure if kernel is loaded at a different
position than the address, 16M, which is decided at compiled time.
Kexec/kdump is such practical case.

To fix it, just assign LOAD_PHYSICAL_ADDR to virt_addr as initial
value.

Tested-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 8391c73 ("x86/KASLR: Randomize virtual address separately")
Link: http://lkml.kernel.org/r/1498567146-11990-3-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-30 08:53:14 +02:00
Baoquan He
b892cb873c x86/boot/KASLR: Add checking for the offset of kernel virtual address randomization
For kernel text KASLR, the virtual address is confined to area of 1G,
[0xffffffff80000000, 0xffffffffc0000000). For the implemenataion of
virtual address randomization, we only randomize to get an offset
between 16M and 1G, then add this offset to the starting address,
0xffffffff80000000. Here 16M is the offset which is decided at linking
stage. So the amount of the local variable 'virt_addr' which respresents
the offset plus the kernel output size can not exceed KERNEL_IMAGE_SIZE.

Add a debug check for the offset. If out of bounds, print error
message and hang there.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1498567146-11990-2-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-30 08:53:14 +02:00
Kirill A. Shutemov
34bbb0009f x86/boot/compressed: Enable 5-level paging during decompression stage
We need to cover two basic cases: when bootloader left us in 32-bit mode
and when bootloader enabled long mode.

The patch implements unified codepath to enabled 5-level paging for both
cases. It means case when we start in 32-bit mode, we first enable long
mode with 4-level and then switch over to 5-level paging.

Switching from 4-level to 5-level paging is not trivial. We cannot do it
directly. Setting LA57 in long mode would trigger #GP. So we need to
switch off long mode first and the then re-enable with 5-level paging.

NOTE: The need of switching off long mode means we are in trouble if
bootloader put us above 4G boundary. If bootloader wants to boot 5-level
paging kernel, it has to put kernel below 4G or enable 5-level paging on
it's own, so we could avoid the step.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-7-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-13 08:56:53 +02:00
Kirill A. Shutemov
919a02d128 x86/boot/efi: Define __KERNEL32_CS GDT on 64-bit configurations
We would need to switch temporarily to compatibility mode during booting
with 5-level paging enabled. It would require 32-bit code segment
descriptor.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-6-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-13 08:56:53 +02:00
Kirill A. Shutemov
4c94117c7f x86/boot/efi: Fix __KERNEL_CS definition of GDT entry on 64-bit configurations
Define __KERNEL_CS GDT entry as long mode (.L=1, .D=0) on 64-bit
configurations.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-13 08:56:52 +02:00
Kirill A. Shutemov
f8fceacbd1 x86/boot/efi: Cleanup initialization of GDT entries
This is preparation for following patches without changing semantics of the
code.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-13 08:56:51 +02:00
Andy Lutomirski
6c690ee103 x86/mm: Split read_cr3() into read_cr3_pa() and __read_cr3()
The kernel has several code paths that read CR3.  Most of them assume that
CR3 contains the PGD's physical address, whereas some of them awkwardly
use PHYSICAL_PAGE_MASK to mask off low bits.

Add explicit mask macros for CR3 and convert all of the CR3 readers.
This will keep them from breaking when PCID is enabled.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: xen-devel <xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/883f8fb121f4616c1c1427ad87350bb2f5ffeca1.1497288170.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-13 08:48:09 +02:00
Arnd Bergmann
5b8b9cf76a x86/KASLR: Use the right memcpy() implementation
The decompressor has its own implementation of the string functions,
but has to include the right header to get those, while implicitly
including linux/string.h may result in a link error:

  arch/x86/boot/compressed/kaslr.o: In function `choose_random_location':
  kaslr.c:(.text+0xf51): undefined reference to `_mmx_memcpy'

This has appeared now as KASLR started using memcpy(), via:

	d52e7d5a95 ("x86/KASLR: Parse all 'memmap=' boot option entries")

Other files in the decompressor already do the same thing.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170530091446.1000183-1-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-31 07:59:45 +02:00
Baoquan He
4cdba14f84 x86/KASLR: Handle the memory limit specified by the 'memmap=' and 'mem=' boot options
The 'mem=' boot option limits the max address a system can use - any memory
region above the limit will be removed.

Furthermore, the 'memmap=nn[KMG]' variant (with no offset specified) has the same
behaviour as 'mem='.

KASLR needs to consider this when choosing the random position for
decompressing the kernel. Do it.

Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dan.j.williams@intel.com
Cc: douly.fnst@cn.fujitsu.com
Cc: dyoung@redhat.com
Link: http://lkml.kernel.org/r/1494654390-23861-3-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-24 09:50:27 +02:00
Baoquan He
d52e7d5a95 x86/KASLR: Parse all 'memmap=' boot option entries
In commit:

  f28442497b ("x86/boot: Fix KASLR and memmap= collision")

... the memmap= option is parsed so that KASLR can avoid those reserved
regions. It uses cmdline_find_option() to get the value if memmap=
is specified, however the problem is that cmdline_find_option() can only
find the last entry if multiple memmap entries are provided. This
is not correct.

Address this by checking each command line token for a "memmap=" match
and parse each instance instead of using cmdline_find_option().

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dan.j.williams@intel.com
Cc: douly.fnst@cn.fujitsu.com
Cc: dyoung@redhat.com
Cc: m.mizuma@jp.fujitsu.com
Link: http://lkml.kernel.org/r/1494654390-23861-2-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-24 09:50:27 +02:00
Rob Landley
3780578761 x86/boot: Use CROSS_COMPILE prefix for readelf
The boot code Makefile contains a straight 'readelf' invocation. This
causes build warnings in cross compile environments, when there is no
unprefixed readelf accessible via $PATH.

Add the missing $(CROSS_COMPILE) prefix.

[ tglx: Rewrote changelog ]

Fixes: 98f7852537 ("x86/boot: Refuse to build with data relocations")
Signed-off-by: Rob Landley <rob@landley.net>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: "H.J. Lu" <hjl.tools@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/ced18878-693a-9576-a024-113ef39a22c0@landley.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-05-21 13:04:27 +02:00
Xunlei Pang
66aad4fdf2 x86/mm: Add support for gbpages to kernel_ident_mapping_init()
Kernel identity mappings on x86-64 kernels are created in two
ways: by the early x86 boot code, or by kernel_ident_mapping_init().

Native kernels (which is the dominant usecase) use the former,
but the kexec and the hibernation code uses kernel_ident_mapping_init().

There's a subtle difference between these two ways of how identity
mappings are created, the current kernel_ident_mapping_init() code
creates identity mappings always using 2MB page(PMD level) - while
the native kernel boot path also utilizes gbpages where available.

This difference is suboptimal both for performance and for memory
usage: kernel_ident_mapping_init() needs to allocate pages for the
page tables when creating the new identity mappings.

This patch adds 1GB page(PUD level) support to kernel_ident_mapping_init()
to address these concerns.

The primary advantage would be better TLB coverage/performance,
because we'd utilize 1GB TLBs instead of 2MB ones.

It is also useful for machines with large number of memory to
save paging structure allocations(around 4MB/TB using 2MB page)
when setting identity mappings for all the memory, after using
1GB page it will consume only 8KB/TB.

( Note that this change alone does not activate gbpages in kexec,
  we are doing that in a separate patch. )

Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: akpm@linux-foundation.org
Cc: kexec@lists.infradead.org
Link: http://lkml.kernel.org/r/1493862171-8799-1-git-send-email-xlpang@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-08 08:28:40 +02:00
Kees Cook
60854a12d2 x86/boot: Declare error() as noreturn
The compressed boot function error() is used to halt execution, but it
wasn't marked with "noreturn". This fixes that in preparation for
supporting kernel FORTIFY_SOURCE, which uses the noreturn annotation
on panic, and calls error(). GCC would warn about a noreturn function
calling a non-noreturn function:

  arch/x86/boot/compressed/misc.c: In function ‘fortify_panic’:
  arch/x86/boot/compressed/misc.c:416:1: warning: ‘noreturn’ function does return
   }
 ^

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/20170506045116.GA2879@beast
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-07 10:59:05 +02:00
Baoquan He
da63b6b200 x86/KASLR: Fix kexec kernel boot crash when KASLR randomization fails
Dave found that a kdump kernel with KASLR enabled will reset to the BIOS
immediately if physical randomization failed to find a new position for
the kernel. A kernel with the 'nokaslr' option works in this case.

The reason is that KASLR will install a new page table for the identity
mapping, while it missed building it for the original kernel location
if KASLR physical randomization fails.

This only happens in the kexec/kdump kernel, because the identity mapping
has been built for kexec/kdump in the 1st kernel for the whole memory by
calling init_pgtable(). Here if physical randomizaiton fails, it won't build
the identity mapping for the original area of the kernel but change to a
new page table '_pgtable'. Then the kernel will triple fault immediately
caused by no identity mappings.

The normal kernel won't see this bug, because it comes here via startup_32()
and CR3 will be set to _pgtable already. In startup_32() the identity
mapping is built for the 0~4G area. In KASLR we just append to the existing
area instead of entirely overwriting it for on-demand identity mapping
building. So the identity mapping for the original area of kernel is still
there.

To fix it we just switch to the new identity mapping page table when physical
KASLR succeeds. Otherwise we keep the old page table unchanged just like
"nokaslr" does.

Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Dave Young <dyoung@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1493278940-5885-1-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-28 08:31:15 +02:00
Ingo Molnar
4729277156 Merge branch 'WIP.x86/boot' into x86/boot, to pick up ready branch
The E820 rework in WIP.x86/boot has gone through a couple of weeks
of exposure in -tip, merge it in a wider fashion.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11 08:49:31 +02:00
Zhengyi Shen
5af218439f x86/boot: Fix Sparse warning by including required header file
Include declarations for various symbols defined in the error.h header file
to fix the following Sparse warnings:

  arch/x86/boot/compressed/error.c:8:6:
	warning: symbol 'warn' was not declared. Should it be static?
  arch/x86/boot/compressed/error.c:15:6:
	warning: symbol 'error' was not declared. Should it be static?

Signed-off-by: Zhengyi Shen <shenzhengyi@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1490770820-24472-1-git-send-email-shenzhengyi@gmail.com
[ Fixed/enhanced the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-31 08:13:54 +02:00
Ingo Molnar
0871d5a66d Merge branch 'linus' into WIP.x86/boot, to fix up conflicts and to pick up updates
Conflicts:
	arch/x86/xen/setup.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-01 09:02:26 +01:00
Linus Torvalds
292d386743 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "Misc updates:

   - fix e820 error handling

   - convert page table setup code from assembly to C

   - fix kexec environment bug

   - ... plus small cleanups"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/kconfig: Remove misleading note regarding hibernation and KASLR
  x86/boot: Fix KASLR and memmap= collision
  x86/e820/32: Fix e820_search_gap() error handling on x86-32
  x86/boot/32: Convert the 32-bit pgtable setup code from assembly to C
  x86/e820: Make e820_search_gap() static and remove unused variables
2017-02-20 14:04:37 -08:00
David Howells
de8cb45862 efi: Get and store the secure boot status
Get the firmware's secure-boot status in the kernel boot wrapper and stash
it somewhere that the main kernel image can find.

The efi_get_secureboot() function is extracted from the ARM stub and (a)
generalised so that it can be called from x86 and (b) made to use
efi_call_runtime() so that it can be run in mixed-mode.

For x86, it is stored in boot_params and can be overridden by the boot
loader or kexec.  This allows secure-boot mode to be passed on to a new
kernel.

Suggested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1486380166-31868-5-git-send-email-ard.biesheuvel@linaro.org
[ Small readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-07 10:42:10 +01:00