Commit Graph

466 Commits

Author SHA1 Message Date
Thomas Gleixner 1e90a13d0c x86/smpboot: Init apic mapping before usage
The recent changes, which forced the registration of the boot cpu on UP
systems, which do not have ACPI tables, have been fixed for systems w/o
local APIC, but left a wreckage for systems which have neither ACPI nor
mptables, but the CPU has an APIC, e.g. virtualbox.

The boot process crashes in prefill_possible_map() as it wants to register
the boot cpu, which needs to access the local apic, but the local APIC is
not yet mapped.

There is no reason why init_apic_mapping() can't be invoked before
prefill_possible_map(). So instead of playing another silly early mapping
game, as the ACPI/mptables code does, we just move init_apic_mapping()
before the call to prefill_possible_map().

In hindsight, I should have noticed that combination earlier.

Sorry for the churn (also in stable)!

Fixes: ff8560512b ("x86/boot/smp: Don't try to poke disabled/non-existent APIC")
Reported-and-debugged-by: Michal Necasek <michal.necasek@oracle.com>
Reported-and-tested-by: Wolfgang Bauer <wbauer@tmo.at>
Cc: prarit@redhat.com
Cc: ville.syrjala@linux.intel.com
Cc: michael.thayer@oracle.com
Cc: knut.osmundsen@oracle.com
Cc: frank.mehnert@oracle.com
Cc: Borislav Petkov <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1610282114380.5053@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-10-29 14:00:46 +02:00
Linus Torvalds 3ef0a61a46 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 changes in this cycle were:

   - Save e820 table RAM footprint on larger kernel configurations.
     (Denys Vlasenko)

   - pmem related fixes (Dan Williams)

   - theoretical e820 boundary condition fix (Wei Yang)"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Fix kdump, cleanup aborted E820_PRAM max_pfn manipulation
  x86/e820: Use much less memory for e820/e820_saved, save up to 120k
  x86/e820: Prepare e280 code for switch to dynamic storage
  x86/e820: Mark some static functions __init
  x86/e820: Fix very large 'size' handling boundary condition
2016-10-03 16:46:53 -07:00
Linus Torvalds 1a4a2bc460 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull low-level x86 updates from Ingo Molnar:
 "In this cycle this topic tree has become one of those 'super topics'
  that accumulated a lot of changes:

   - Add CONFIG_VMAP_STACK=y support to the core kernel and enable it on
     x86 - preceded by an array of changes. v4.8 saw preparatory changes
     in this area already - this is the rest of the work. Includes the
     thread stack caching performance optimization. (Andy Lutomirski)

   - switch_to() cleanups and all around enhancements. (Brian Gerst)

   - A large number of dumpstack infrastructure enhancements and an
     unwinder abstraction. The secret long term plan is safe(r) live
     patching plus maybe another attempt at debuginfo based unwinding -
     but all these current bits are standalone enhancements in a frame
     pointer based debug environment as well. (Josh Poimboeuf)

   - More __ro_after_init and const annotations. (Kees Cook)

   - Enable KASLR for the vmemmap memory region. (Thomas Garnier)"

[ The virtually mapped stack changes are pretty fundamental, and not
  x86-specific per se, even if they are only used on x86 right now. ]

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits)
  x86/asm: Get rid of __read_cr4_safe()
  thread_info: Use unsigned long for flags
  x86/alternatives: Add stack frame dependency to alternative_call_2()
  x86/dumpstack: Fix show_stack() task pointer regression
  x86/dumpstack: Remove dump_trace() and related callbacks
  x86/dumpstack: Convert show_trace_log_lvl() to use the new unwinder
  oprofile/x86: Convert x86_backtrace() to use the new unwinder
  x86/stacktrace: Convert save_stack_trace_*() to use the new unwinder
  perf/x86: Convert perf_callchain_kernel() to use the new unwinder
  x86/unwind: Add new unwind interface and implementations
  x86/dumpstack: Remove NULL task pointer convention
  fork: Optimize task creation by caching two thread stacks per CPU if CONFIG_VMAP_STACK=y
  sched/core: Free the stack early if CONFIG_THREAD_INFO_IN_TASK
  lib/syscall: Pin the task stack in collect_syscall()
  x86/process: Pin the target stack in get_wchan()
  x86/dumpstack: Pin the target stack when dumping it
  kthread: Pin the stack via try_get_task_stack()/put_task_stack() in to_live_kthread() function
  sched/core: Add try_get_task_stack() and put_task_stack()
  x86/entry/64: Fix a minor comment rebase error
  iommu/amd: Don't put completion-wait semaphore on stack
  ...
2016-10-03 16:13:28 -07:00
Linus Torvalds 110a9e42b6 Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 apic updates from Ingo Molnar:
 "The main changes are:

   - Persistent CPU/node numbering across CPU hotplug/unplug events.
     This is a pretty involved series of changes that first fetches all
     the information during bootup and then uses it for the various
     hotplug/unplug methods. (Gu Zheng, Dou Liyang)

   - IO-APIC hot-add/remove fixes and enhancements. (Rui Wang)

   - ... various fixes, cleanups and enhancements"

* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  x86/apic: Fix silent & fatal merge conflict in __generic_processor_info()
  acpi: Fix broken error check in map_processor()
  acpi: Validate processor id when mapping the processor
  acpi: Provide mechanism to validate processors in the ACPI tables
  x86/acpi: Set persistent cpuid <-> nodeid mapping when booting
  x86/acpi: Enable MADT APIs to return disabled apicids
  x86/acpi: Introduce persistent storage for cpuid <-> apicid mapping
  x86/acpi: Enable acpi to register all possible cpus at boot time
  x86/numa: Online memory-less nodes at boot time
  x86/apic: Get rid of apic_version[] array
  x86/apic: Order irq_enter/exit() calls correctly vs. ack_APIC_irq()
  x86/ioapic: Ignore root bridges without a companion ACPI device
  x86/apic: Update comment about disabling processor focus
  x86/smpboot: Check APIC ID before setting up default routing
  x86/ioapic: Fix IOAPIC failing to request resource
  x86/ioapic: Fix lost IOAPIC resource after hot-removal and hotadd
  x86/ioapic: Fix setup_res() failing to get resource
  x86/ioapic: Support hot-removal of IOAPICs present during boot
  x86/ioapic: Change prototype of acpi_ioapic_add()
  x86/apic, ACPI: Fix incorrect assignment when handling apic/x2apic entries
  ...
2016-10-03 15:36:06 -07:00
Linus Torvalds de956b8f45 Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "Main changes in this cycle were:

   - Refactor the EFI memory map code into architecture neutral files
     and allow drivers to permanently reserve EFI boot services regions
     on x86, as well as ARM/arm64. (Matt Fleming)

   - Add ARM support for the EFI ESRT driver. (Ard Biesheuvel)

   - Make the EFI runtime services and efivar API interruptible by
     swapping spinlocks for semaphores. (Sylvain Chouleur)

   - Provide the EFI identity mapping for kexec which allows kexec to
     work on SGI/UV platforms with requiring the "noefi" kernel command
     line parameter. (Alex Thorlton)

   - Add debugfs node to dump EFI page tables on arm64. (Ard Biesheuvel)

   - Merge the EFI test driver being carried out of tree until now in
     the FWTS project. (Ivan Hu)

   - Expand the list of flags for classifying EFI regions as "RAM" on
     arm64 so we align with the UEFI spec. (Ard Biesheuvel)

   - Optimise out the EFI mixed mode if it's unsupported (CONFIG_X86_32)
     or disabled (CONFIG_EFI_MIXED=n) and switch the early EFI boot
     services function table for direct calls, alleviating us from
     having to maintain the custom function table. (Lukas Wunner)

   - Miscellaneous cleanups and fixes"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  x86/efi: Round EFI memmap reservations to EFI_PAGE_SIZE
  x86/efi: Allow invocation of arbitrary boot services
  x86/efi: Optimize away setup_gop32/64 if unused
  x86/efi: Use kmalloc_array() in efi_call_phys_prolog()
  efi/arm64: Treat regions with WT/WC set but WB cleared as memory
  efi: Add efi_test driver for exporting UEFI runtime service interfaces
  x86/efi: Defer efi_esrt_init until after memblock_x86_fill
  efi/arm64: Add debugfs node to dump UEFI runtime page tables
  x86/efi: Remove unused find_bits() function
  fs/efivarfs: Fix double kfree() in error path
  x86/efi: Map in physical addresses in efi_map_region_fixed
  lib/ucs2_string: Speed up ucs2_utf8size()
  firmware-gsmi: Delete an unnecessary check before the function call "dma_pool_destroy"
  x86/efi: Initialize status to ensure garbage is not returned on small size
  efi: Replace runtime services spinlock with semaphore
  efi: Don't use spinlocks for efi vars
  efi: Use a file local lock for efivars
  efi/arm*: esrt: Add missing call to efi_esrt_init()
  efi/esrt: Use memremap not ioremap to access ESRT table in memory
  x86/efi-bgrt: Use efi_mem_reserve() to avoid copying image data
  ...
2016-10-03 11:33:18 -07:00
Andy Lutomirski 1ef55be16e x86/asm: Get rid of __read_cr4_safe()
We use __read_cr4() vs __read_cr4_safe() inconsistently.  On
CR4-less CPUs, all CR4 bits are effectively clear, so we can make
the code simpler and more robust by making __read_cr4() always fix
up faults on 32-bit kernels.

This may fix some bugs on old 486-like CPUs, but I don't have any
easy way to test that.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: david@saggiorato.net
Link: http://lkml.kernel.org/r/ea647033d357d9ce2ad2bbde5a631045f5052fb6.1475178370.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-30 12:40:12 +02:00
Thomas Gleixner d7e25c66c9 Merge branch 'x86/urgent' into x86/asm
Get the cr4 fixes so we can apply the final cleanup
2016-09-30 12:38:28 +02:00
Andy Lutomirski 192d1dccbf x86/boot: Fix another __read_cr4() case on 486
The condition for reading CR4 was wrong: there are some CPUs with
CPUID but not CR4.  Rather than trying to make the condition exact,
use __read_cr4_safe().

Fixes: 18bc7bd523 ("x86/boot: Synchronize trampoline_cr4_features and mmu_cr4_features directly")
Reported-by: david@saggiorato.net
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Link: http://lkml.kernel.org/r/8c453a61c4f44ab6ff43c29780ba04835234d2e5.1475178369.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-30 12:37:40 +02:00
Denys Vlasenko 475339684e x86/e820: Prepare e280 code for switch to dynamic storage
This patch turns e820 and e820_saved into pointers to e820 tables,
of the same size as before.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
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: 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: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20160917213927.1787-2-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-21 15:02:12 +02:00
Ricardo Neri 3dad6f7f69 x86/efi: Defer efi_esrt_init until after memblock_x86_fill
Commit 7b02d53e7852 ("efi: Allow drivers to reserve boot services forever")
introduced a new efi_mem_reserve to reserve the boot services memory
regions forever. This reservation involves allocating a new EFI memory
range descriptor. However, allocation can only succeed if there is memory
available for the allocation. Otherwise, error such as the following may
occur:

esrt: Reserving ESRT space from 0x000000003dd6a000 to 0x000000003dd6a010.
Kernel panic - not syncing: ERROR: Failed to allocate 0x9f0 bytes below \
 0x0.
CPU: 0 PID: 0 Comm: swapper Not tainted 4.7.0-rc5+ #503
 0000000000000000 ffffffff81e03ce0 ffffffff8131dae8 ffffffff81bb6c50
 ffffffff81e03d70 ffffffff81e03d60 ffffffff8111f4df 0000000000000018
 ffffffff81e03d70 ffffffff81e03d08 00000000000009f0 00000000000009f0
Call Trace:
 [<ffffffff8131dae8>] dump_stack+0x4d/0x65
 [<ffffffff8111f4df>] panic+0xc5/0x206
 [<ffffffff81f7c6d3>] memblock_alloc_base+0x29/0x2e
 [<ffffffff81f7c6e3>] memblock_alloc+0xb/0xd
 [<ffffffff81f6c86d>] efi_arch_mem_reserve+0xbc/0x134
 [<ffffffff81fa3280>] efi_mem_reserve+0x2c/0x31
 [<ffffffff81fa3280>] ? efi_mem_reserve+0x2c/0x31
 [<ffffffff81fa40d3>] efi_esrt_init+0x19e/0x1b4
 [<ffffffff81f6d2dd>] efi_init+0x398/0x44a
 [<ffffffff81f5c782>] setup_arch+0x415/0xc30
 [<ffffffff81f55af1>] start_kernel+0x5b/0x3ef
 [<ffffffff81f55434>] x86_64_start_reservations+0x2f/0x31
 [<ffffffff81f55520>] x86_64_start_kernel+0xea/0xed
---[ end Kernel panic - not syncing: ERROR: Failed to allocate 0x9f0
     bytes below 0x0.

An inspection of the memblock configuration reveals that there is no memory
available for the allocation:

MEMBLOCK configuration:
 memory size = 0x0 reserved size = 0x4f339c0
 memory.cnt  = 0x1
 memory[0x0]    [0x00000000000000-0xffffffffffffffff], 0x0 bytes on node 0\
                 flags: 0x0
 reserved.cnt  = 0x4
 reserved[0x0]  [0x0000000008c000-0x0000000008c9bf], 0x9c0 bytes flags: 0x0
 reserved[0x1]  [0x0000000009f000-0x000000000fffff], 0x61000 bytes\
                 flags: 0x0
 reserved[0x2]  [0x00000002800000-0x0000000394bfff], 0x114c000 bytes\
                 flags: 0x0
 reserved[0x3]  [0x000000304e4000-0x00000034269fff], 0x3d86000 bytes\
                 flags: 0x0

This situation can be avoided if we call efi_esrt_init after memblock has
memory regions for the allocation.

Also, the EFI ESRT driver makes use of early_memremap'pings. Therfore, we
do not want to defer efi_esrt_init for too long. We must call such function
while calls to early_memremap are still valid.

A good place to meet the two aforementioned conditions is right after
memblock_x86_fill, grouped with other EFI-related functions.

Reported-by: Scott Lawson <scott.lawson@intel.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Peter Jones <pjones@redhat.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:08:52 +01:00
Matt Fleming 4971531af3 x86/efi: Test for EFI_MEMMAP functionality when iterating EFI memmap
Both efi_find_mirror() and efi_fake_memmap() really want to know
whether the EFI memory map is available, not just whether the machine
was booted using EFI. efi_fake_memmap() even has a check for
EFI_MEMMAP at the start of the function.

Since we've already got other code that has this dependency, merge
everything under one if() conditional, and remove the now superfluous
check from efi_fake_memmap().

Tested-by: Dave Young <dyoung@redhat.com> [kexec/kdump]
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [arm]
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:06:34 +01:00
Ingo Molnar 2b3061c77c Merge branch 'x86/mm' into x86/asm, to unify the two branches for simplicity
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-08 08:41:52 +02:00
Baoquan He a91bf718db x86/mm/numa: Open code function early_get_boot_cpu_id()
Previously early_acpi_boot_init() was called in early_get_boot_cpu_id()
to get the value for boot_cpu_physical_apicid. Now early_acpi_boot_init()
has been taken out and moved to setup_arch(), the name of
early_get_boot_cpu_id() doesn't match its implementation anymore, and
only the getting boot-time SMP configuration code was left.

So in this patch we open code it.

Also move the smp_found_config check into default_get_smp_config to
simplify code, because both early_get_smp_config() and get_smp_config()
call x86_init.mpparse.get_smp_config().

Also remove the redundent CONFIG_X86_MPPARSE #ifdef check when we call
early_get_smp_config().

Signed-off-by: Baoquan He <bhe@redhat.com>
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: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-acpi@vger.kernel.org
Cc: rjw@rjwysocki.net
Link: http://lkml.kernel.org/r/1470985033-22493-1-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-15 08:51:54 +02:00
Andy Lutomirski d0de0f685d x86/boot: Defer setup_real_mode() to early_initcall time
There's no need to run setup_real_mode() as early as we run it.
Defer it to the same early_initcall that sets up the page
permissions for the real mode code.

This should be a code size reduction.  More importantly, it give us
a longer window in which we can allocate the real mode trampoline.

Signed-off-by: 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: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/fd62f0da4f79357695e9bf3e365623736b05f119.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 11:15:00 +02:00
Andy Lutomirski 18bc7bd523 x86/boot: Synchronize trampoline_cr4_features and mmu_cr4_features directly
The initialization process for trampoline_cr4_features and
mmu_cr4_features was confusing.  The intent is for mmu_cr4_features
and *trampoline_cr4_features to stay in sync, but
trampoline_cr4_features is NULL until setup_real_mode() runs.  The
old code synchronized *trampoline_cr4_features *twice*, once in
setup_real_mode() and once in setup_arch().  It also initialized
mmu_cr4_features in setup_real_mode(), which causes the actual value
of mmu_cr4_features to potentially depend on when setup_real_mode()
is called.

With this patch, mmu_cr4_features is initialized directly in
setup_arch(), and *trampoline_cr4_features is synchronized to
mmu_cr4_features when the trampoline is set up.

After this patch, it should be safe to defer setup_real_mode().

Signed-off-by: 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: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/d48a263f9912389b957dd495a7127b009259ffe0.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 11:15:00 +02:00
Andy Lutomirski 007b756053 x86/boot: Run reserve_bios_regions() after we initialize the memory map
reserve_bios_regions() is a quirk that reserves memory that we might
otherwise think is available.  There's no need to run it so early,
and running it before we have the memory map initialized with its
non-quirky inputs makes it hard to make reserve_bios_regions() more
intelligent.

Move it right after we populate the memblock state.

Signed-off-by: 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: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/59f58618911005c799c6c9979ce6ae4881d907c2.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-11 11:14:59 +02:00
Kees Cook 404f6aac9b x86: Apply more __ro_after_init and const
Guided by grsecurity's analogous __read_only markings in arch/x86,
this applies several uses of __ro_after_init to structures that are
only updated during __init, and const for some structures that are
never updated.  Additionally extends __init markings to some functions
that are only used during __init, and cleans up some missing C99 style
static initializers.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Brown <david.brown@linaro.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20160808232906.GA29731@www.outflux.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 14:55:05 +02:00
Thomas Garnier c7d2361f75 x86/mm/KASLR: Fix physical memory calculation on KASLR memory randomization
Initialize KASLR memory randomization after max_pfn is initialized. Also
ensure the size is rounded up. It could create problems on machines
with more than 1Tb of memory on certain random addresses.

Signed-off-by: Thomas Garnier <thgarnie@google.com>
Cc: Aleksey Makarov <aleksey.makarov@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: kernel-hardening@lists.openwall.com
Fixes: 021182e52f ("Enable KASLR for physical mapping memory regions")
Link: http://lkml.kernel.org/r/1470762665-88032-1-git-send-email-thgarnie@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 14:45:19 +02:00
Linus Torvalds aeb35d6b74 Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 header cleanups from Ingo Molnar:
 "This tree is a cleanup of the x86 tree reducing spurious uses of
  module.h - which should improve build performance a bit"

* 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, crypto: Restore MODULE_LICENSE() to glue_helper.c so it loads
  x86/apic: Remove duplicated include from probe_64.c
  x86/ce4100: Remove duplicated include from ce4100.c
  x86/headers: Include spinlock_types.h in x8664_ksyms_64.c for missing spinlock_t
  x86/platform: Delete extraneous MODULE_* tags fromm ts5500
  x86: Audit and remove any remaining unnecessary uses of module.h
  x86/kvm: Audit and remove any unnecessary uses of module.h
  x86/xen: Audit and remove any unnecessary uses of module.h
  x86/platform: Audit and remove any unnecessary uses of module.h
  x86/lib: Audit and remove any unnecessary uses of module.h
  x86/kernel: Audit and remove any unnecessary uses of module.h
  x86/mm: Audit and remove any unnecessary uses of module.h
  x86: Don't use module.h just for AUTHOR / LICENSE tags
2016-08-01 14:23:42 -04:00
Linus Torvalds e663107fa1 ACPI material for v4.8-rc1
- Support for ACPI SSDT overlays allowing Secondary System
    Description Tables (SSDTs) to be loaded at any time from EFI
    variables or via configfs (Octavian Purdila, Mika Westerberg).
 
  - Support for the ACPI LPI (Low-Power Idle) feature introduced in
    ACPI 6.0 and allowing processor idle states to be represented in
    ACPI tables in a hierarchical way (with the help of Processor
    Container objects) and support for ACPI idle states management
    on ARM64, based on LPI (Sudeep Holla).
 
  - General improvements of ACPI support for NUMA and ARM64 support
    for ACPI-based NUMA (Hanjun Guo, David Daney, Robert Richter).
 
  - General improvements of the ACPI table upgrade mechanism and
    ARM64 support for that feature (Aleksey Makarov, Jon Masters).
 
  - Support for the Boot Error Record Table (BERT) in APEI and
    improvements of kernel messages printed by the error injection
    code (Huang Ying, Borislav Petkov).
 
  - New driver for the Intel Broxton WhiskeyCove PMIC operation
    region and support for the REGS operation region on Broxton,
    PMIC code cleanups (Bin Gao, Felipe Balbi, Paul Gortmaker).
 
  - New driver for the power participant device which is part of the
    Dynamic Power and Thermal Framework (DPTF) and DPTF-related code
    reorganization (Srinivas Pandruvada).
 
  - Support for the platform-initiated graceful shutdown feature
    introduced in ACPI 6.1 (Prashanth Prakash).
 
  - ACPI button driver update related to lid input events generated
    automatically on initialization and system resume that have been
    problematic for some time (Lv Zheng).
 
  - ACPI EC driver cleanups (Lv Zheng).
 
  - Documentation of the ACPICA release automation process and the
    in-kernel ACPI AML debugger (Lv Zheng).
 
  - New blacklist entry and two fixes for the ACPI backlight driver
    (Alex Hung, Arvind Yadav, Ralf Gerbig).
 
  - Cleanups of the ACPI pci_slot driver (Joe Perches, Paul Gortmaker).
 
  - ACPI CPPC code changes to make it more robust against possible
    defects in ACPI tables and new symbol definitions for PCC (Hoan
    Tran).
 
  - System reboot code modification to execute the ACPI _PTS (Prepare
    To Sleep) method in addition to _TTS (Ocean He).
 
  - ACPICA-related change to carry out lock ordering checks in ACPICA
    if ACPICA debug is enabled in the kernel (Lv Zheng).
 
  - Assorted minor fixes and cleanups (Andy Shevchenko, Baoquan He,
    Bhaktipriya Shridhar, Paul Gortmaker, Rafael Wysocki).
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Merge tag 'acpi-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:
 "The new feaures here are the support for ACPI overlays (allowing ACPI
  tables to be loaded at any time from EFI variables or via configfs)
  and the LPI (Low-Power Idle) support.  Also notable is the ACPI-based
  NUMA support for ARM64.

  Apart from that we have two new drivers, for the DPTF (Dynamic Power
  and Thermal Framework) power participant device and for the Intel
  Broxton WhiskeyCove PMIC, some more PMIC-related changes, support for
  the Boot Error Record Table (BERT) in APEI and support for
  platform-initiated graceful shutdown.

  Plus two new pieces of documentation and usual assorted fixes and
  cleanups in quite a few places.

  Specifics:

   - Support for ACPI SSDT overlays allowing Secondary System
     Description Tables (SSDTs) to be loaded at any time from EFI
     variables or via configfs (Octavian Purdila, Mika Westerberg).

   - Support for the ACPI LPI (Low-Power Idle) feature introduced in
     ACPI 6.0 and allowing processor idle states to be represented in
     ACPI tables in a hierarchical way (with the help of Processor
     Container objects) and support for ACPI idle states management on
     ARM64, based on LPI (Sudeep Holla).

   - General improvements of ACPI support for NUMA and ARM64 support for
     ACPI-based NUMA (Hanjun Guo, David Daney, Robert Richter).

   - General improvements of the ACPI table upgrade mechanism and ARM64
     support for that feature (Aleksey Makarov, Jon Masters).

   - Support for the Boot Error Record Table (BERT) in APEI and
     improvements of kernel messages printed by the error injection code
     (Huang Ying, Borislav Petkov).

   - New driver for the Intel Broxton WhiskeyCove PMIC operation region
     and support for the REGS operation region on Broxton, PMIC code
     cleanups (Bin Gao, Felipe Balbi, Paul Gortmaker).

   - New driver for the power participant device which is part of the
     Dynamic Power and Thermal Framework (DPTF) and DPTF-related code
     reorganization (Srinivas Pandruvada).

   - Support for the platform-initiated graceful shutdown feature
     introduced in ACPI 6.1 (Prashanth Prakash).

   - ACPI button driver update related to lid input events generated
     automatically on initialization and system resume that have been
     problematic for some time (Lv Zheng).

   - ACPI EC driver cleanups (Lv Zheng).

   - Documentation of the ACPICA release automation process and the
     in-kernel ACPI AML debugger (Lv Zheng).

   - New blacklist entry and two fixes for the ACPI backlight driver
     (Alex Hung, Arvind Yadav, Ralf Gerbig).

   - Cleanups of the ACPI pci_slot driver (Joe Perches, Paul Gortmaker).

   - ACPI CPPC code changes to make it more robust against possible
     defects in ACPI tables and new symbol definitions for PCC (Hoan
     Tran).

   - System reboot code modification to execute the ACPI _PTS (Prepare
     To Sleep) method in addition to _TTS (Ocean He).

   - ACPICA-related change to carry out lock ordering checks in ACPICA
     if ACPICA debug is enabled in the kernel (Lv Zheng).

   - Assorted minor fixes and cleanups (Andy Shevchenko, Baoquan He,
     Bhaktipriya Shridhar, Paul Gortmaker, Rafael Wysocki)"

* tag 'acpi-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (71 commits)
  ACPI: enable ACPI_PROCESSOR_IDLE on ARM64
  arm64: add support for ACPI Low Power Idle(LPI)
  drivers: firmware: psci: initialise idle states using ACPI LPI
  cpuidle: introduce CPU_PM_CPU_IDLE_ENTER macro for ARM{32, 64}
  arm64: cpuidle: drop __init section marker to arm_cpuidle_init
  ACPI / processor_idle: Add support for Low Power Idle(LPI) states
  ACPI / processor_idle: introduce ACPI_PROCESSOR_CSTATE
  ACPI / DPTF: move int340x_thermal.c to the DPTF folder
  ACPI / DPTF: Add DPTF power participant driver
  ACPI / lpat: make it explicitly non-modular
  ACPI / dock: make dock explicitly non-modular
  ACPI / PCI: make pci_slot explicitly non-modular
  ACPI / PMIC: remove modular references from non-modular code
  ACPICA: Linux: Enable ACPI_MUTEX_DEBUG for Linux kernel
  ACPI: Rename configfs.c to acpi_configfs.c to prevent link error
  ACPI / debugger: Add AML debugger documentation
  ACPI: Add documentation describing ACPICA release automation
  ACPI: add support for loading SSDTs via configfs
  ACPI: add support for configfs
  efi / ACPI: load SSTDs from EFI variables
  ...
2016-07-26 17:56:45 -07:00
Paul Gortmaker 186f43608a x86/kernel: Audit and remove any unnecessary uses of module.h
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.  Build testing
revealed some implicit header usage that was fixed up accordingly.

Note that some bool/obj-y instances remain since module.h is
the header for some exception table entry stuff, and for things
like __init_or_module (code that is tossed when MODULES=n).

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.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/20160714001901.31603-4-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 15:06:41 +02:00
Thomas Garnier 0483e1fa6e x86/mm: Implement ASLR for kernel memory regions
Randomizes the virtual address space of kernel memory regions for
x86_64. This first patch adds the infrastructure and does not randomize
any region. The following patches will randomize the physical memory
mapping, vmalloc and vmemmap regions.

This security feature mitigates exploits relying on predictable kernel
addresses. These addresses can be used to disclose the kernel modules
base addresses or corrupt specific structures to elevate privileges
bypassing the current implementation of KASLR. This feature can be
enabled with the CONFIG_RANDOMIZE_MEMORY option.

The order of each memory region is not changed. The feature looks at the
available space for the regions based on different configuration options
and randomizes the base and space between each. The size of the physical
memory mapping is the available physical memory. No performance impact
was detected while testing the feature.

Entropy is generated using the KASLR early boot functions now shared in
the lib directory (originally written by Kees Cook). Randomization is
done on PGD & PUD page table levels to increase possible addresses. The
physical memory mapping code was adapted to support PUD level virtual
addresses. This implementation on the best configuration provides 30,000
possible virtual addresses in average for each memory region.  An
additional low memory page is used to ensure each CPU can start with a
PGD aligned virtual address (for realmode).

x86/dump_pagetable was updated to correctly display each region.

Updated documentation on x86_64 memory layout accordingly.

Performance data, after all patches in the series:

Kernbench shows almost no difference (-+ less than 1%):

Before:

Average Optimal load -j 12 Run (std deviation): Elapsed Time 102.63 (1.2695)
User Time 1034.89 (1.18115) System Time 87.056 (0.456416) Percent CPU 1092.9
(13.892) Context Switches 199805 (3455.33) Sleeps 97907.8 (900.636)

After:

Average Optimal load -j 12 Run (std deviation): Elapsed Time 102.489 (1.10636)
User Time 1034.86 (1.36053) System Time 87.764 (0.49345) Percent CPU 1095
(12.7715) Context Switches 199036 (4298.1) Sleeps 97681.6 (1031.11)

Hackbench shows 0% difference on average (hackbench 90 repeated 10 times):

attemp,before,after 1,0.076,0.069 2,0.072,0.069 3,0.066,0.066 4,0.066,0.068
5,0.066,0.067 6,0.066,0.069 7,0.067,0.066 8,0.063,0.067 9,0.067,0.065
10,0.068,0.071 average,0.0677,0.0677

Signed-off-by: Thomas Garnier <thgarnie@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/1466556426-32664-6-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-08 17:33:46 +02:00
Aleksey Makarov da3d3f98d2 ACPI / tables: table upgrade: refactor function definitions
Refer initrd_start, initrd_end directly from drivers/acpi/tables.c.
This allows to use the table upgrade feature in architectures
other than x86.  Also this simplifies header files.

The patch renames acpi_table_initrd_init() to acpi_table_upgrade()
(what reflects the purpose of the function) and removes the unneeded
wraps early_acpi_table_init() and early_initrd_acpi_init().

Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Acked-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-22 01:16:14 +02:00
Lv Zheng af06f8b7a1 ACPI / x86: Cleanup initrd related code
In arch/x86/kernel/setup.c, the #ifdef kept for CONFIG_ACPI actually is
related to the accessibility of initrd_start/initrd_end, so the stub should
be provided from this source file and should only be dependent on
CONFIG_BLK_DEV_INITRD.

Note that when ACPI=n and BLK_DEV_INITRD=y, early_initrd_acpi_init() is
still a stub because of the stub prepared for early_acpi_table_init().

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-18 23:59:09 +02:00
Lv Zheng 5ae74f2cc2 ACPI / tables: Move table override mechanisms to tables.c
This patch moves acpi_os_table_override() and
acpi_os_physical_table_override() to tables.c.

Along with the mechanisms, acpi_initrd_initialize_tables() is also moved to
tables.c to form a static function. The following functions are renamed
according to this change:
 1. acpi_initrd_override() -> renamed to early_acpi_table_init(), which
    invokes acpi_table_initrd_init()
 2. acpi_os_physical_table_override() -> which invokes
    acpi_table_initrd_override()
 3. acpi_initialize_initrd_tables() -> renamed to acpi_table_initrd_scan()

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-18 23:59:08 +02:00
Linus Torvalds 4046d6e81f Revert "x86: remove the kernel code/data/bss resources from /proc/iomem"
This reverts commit c4004b02f8.

Sadly, my hope that nobody would actually use the special kernel entries
in /proc/iomem were dashed by kexec.  Which reads /proc/iomem explicitly
to find the kernel base address.  Nasty.

Anyway, that means we can't do the sane and simple thing and just remove
the entries, and we'll instead have to mask them out based on permissions.

Reported-by: Zhengyu Zhang <zhezhang@redhat.com>
Reported-by: Dave Young <dyoung@redhat.com>
Reported-by: Freeman Zhang <freeman.zhang1992@gmail.com>
Reported-by: Emrah Demir <ed@abdsec.com>
Reported-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-14 12:55:32 -07:00
Linus Torvalds c4004b02f8 x86: remove the kernel code/data/bss resources from /proc/iomem
Let's see if anybody even notices.  I doubt anybody uses this, and it
does expose addresses that should be randomized, so let's just remove
the code.  It's old and traditional, and it used to be cute, but we
should have removed this long ago.

If it turns out anybody notices and this breaks something, we'll have to
revert this, and maybe we'll end up using other approaches instead
(using %pK or similar).  But removing unnecessary code is always the
preferred option.

Noted-by: Emrah Demir <ed@abdsec.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-06 13:45:07 -07:00
Linus Torvalds 643ad15d47 Merge branch 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 protection key support from Ingo Molnar:
 "This tree adds support for a new memory protection hardware feature
  that is available in upcoming Intel CPUs: 'protection keys' (pkeys).

  There's a background article at LWN.net:

      https://lwn.net/Articles/643797/

  The gist is that protection keys allow the encoding of
  user-controllable permission masks in the pte.  So instead of having a
  fixed protection mask in the pte (which needs a system call to change
  and works on a per page basis), the user can map a (handful of)
  protection mask variants and can change the masks runtime relatively
  cheaply, without having to change every single page in the affected
  virtual memory range.

  This allows the dynamic switching of the protection bits of large
  amounts of virtual memory, via user-space instructions.  It also
  allows more precise control of MMU permission bits: for example the
  executable bit is separate from the read bit (see more about that
  below).

  This tree adds the MM infrastructure and low level x86 glue needed for
  that, plus it adds a high level API to make use of protection keys -
  if a user-space application calls:

        mmap(..., PROT_EXEC);

  or

        mprotect(ptr, sz, PROT_EXEC);

  (note PROT_EXEC-only, without PROT_READ/WRITE), the kernel will notice
  this special case, and will set a special protection key on this
  memory range.  It also sets the appropriate bits in the Protection
  Keys User Rights (PKRU) register so that the memory becomes unreadable
  and unwritable.

  So using protection keys the kernel is able to implement 'true'
  PROT_EXEC on x86 CPUs: without protection keys PROT_EXEC implies
  PROT_READ as well.  Unreadable executable mappings have security
  advantages: they cannot be read via information leaks to figure out
  ASLR details, nor can they be scanned for ROP gadgets - and they
  cannot be used by exploits for data purposes either.

  We know about no user-space code that relies on pure PROT_EXEC
  mappings today, but binary loaders could start making use of this new
  feature to map binaries and libraries in a more secure fashion.

  There is other pending pkeys work that offers more high level system
  call APIs to manage protection keys - but those are not part of this
  pull request.

  Right now there's a Kconfig that controls this feature
  (CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS) that is default enabled
  (like most x86 CPU feature enablement code that has no runtime
  overhead), but it's not user-configurable at the moment.  If there's
  any serious problem with this then we can make it configurable and/or
  flip the default"

* 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  x86/mm/pkeys: Fix mismerge of protection keys CPUID bits
  mm/pkeys: Fix siginfo ABI breakage caused by new u64 field
  x86/mm/pkeys: Fix access_error() denial of writes to write-only VMA
  mm/core, x86/mm/pkeys: Add execute-only protection keys support
  x86/mm/pkeys: Create an x86 arch_calc_vm_prot_bits() for VMA flags
  x86/mm/pkeys: Allow kernel to modify user pkey rights register
  x86/fpu: Allow setting of XSAVE state
  x86/mm: Factor out LDT init from context init
  mm/core, x86/mm/pkeys: Add arch_validate_pkey()
  mm/core, arch, powerpc: Pass a protection key in to calc_vm_flag_bits()
  x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU
  x86/mm/pkeys: Add Kconfig prompt to existing config option
  x86/mm/pkeys: Dump pkey from VMA in /proc/pid/smaps
  x86/mm/pkeys: Dump PKRU with other kernel registers
  mm/core, x86/mm/pkeys: Differentiate instruction fetches
  x86/mm/pkeys: Optimize fault handling in access_error()
  mm/core: Do not enforce PKEY permissions on remote mm access
  um, pkeys: Add UML arch_*_access_permitted() methods
  mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys
  x86/mm/gup: Simplify get_user_pages() PTE bit handling
  ...
2016-03-20 19:08:56 -07:00
Dave Hansen c1192f8428 x86/mm/pkeys: Dump pkey from VMA in /proc/pid/smaps
The protection key can now be just as important as read/write
permissions on a VMA.  We need some debug mechanism to help
figure out if it is in play.  smaps seems like a logical
place to expose it.

arch/x86/kernel/setup.c is a bit of a weirdo place to put
this code, but it already had seq_file.h and there was not
a much better existing place to put it.

We also use no #ifdef.  If protection keys is .config'd out we
will effectively get the same function as if we used the weak
generic function.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Mark Williamson <mwilliamson@undo-software.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20160212210227.4F8EB3F8@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-18 19:46:29 +01:00
Toshi Kani f33b14a4b9 x86/e820: Set System RAM type and descriptor
Change e820_reserve_resources() to set 'flags' and 'desc' from
e820 types.

Set E820_RESERVED_KERN and E820_RAM's (System RAM) io resource
type to IORESOURCE_SYSTEM_RAM.

Do the same for "Kernel data", "Kernel code", and "Kernel bss",
which are child nodes of System RAM.

I/O resource descriptor is set to 'desc' for entries that are
(and will be) target ranges of walk_iomem_res() and
region_intersects().

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm <linux-mm@kvack.org>
Link: http://lkml.kernel.org/r/1453841853-11383-5-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-30 09:49:57 +01:00
Linus Torvalds 0ffedcda63 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:

   - make the debugfs 'kernel_page_tables' file read-only, as it only
     has read ops.  (Borislav Petkov)

   - micro-optimize clflush_cache_range() (Chris Wilson)

   - swiotlb enhancements, which fixes certain KVM emulated devices
     (Igor Mammedov)

   - fix an LDT related debug message (Jan Beulich)

   - modularize CONFIG_X86_PTDUMP (Kees Cook)

   - tone down an overly alarming warning (Laura Abbott)

   - Mark variable __initdata (Rasmus Villemoes)

   - PAT additions (Toshi Kani)"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Micro-optimise clflush_cache_range()
  x86/mm/pat: Change free_memtype() to support shrinking case
  x86/mm/pat: Add untrack_pfn_moved for mremap
  x86/mm: Drop WARN from multi-BAR check
  x86/LDT: Print the real LDT base address
  x86/mm/64: Enable SWIOTLB if system has SRAT memory regions above MAX_DMA32_PFN
  x86/mm: Introduce max_possible_pfn
  x86/mm/ptdump: Make (debugfs)/kernel_page_tables read-only
  x86/mm/mtrr: Mark the 'range_new' static variable in mtrr_calc_range_state() as __initdata
  x86/mm: Turn CONFIG_X86_PTDUMP into a module
2016-01-11 17:16:01 -08:00
Igor Mammedov 8dd3303001 x86/mm: Introduce max_possible_pfn
max_possible_pfn will be used for tracking max possible
PFN for memory that isn't present in E820 table and
could be hotplugged later.

By default max_possible_pfn is initialized with max_pfn,
but later it could be updated with highest PFN of
hotpluggable memory ranges declared in ACPI SRAT table
if any present.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akataria@vmware.com
Cc: fujita.tomonori@lab.ntt.co.jp
Cc: konrad.wilk@oracle.com
Cc: pbonzini@redhat.com
Cc: revers@redhat.com
Cc: riel@redhat.com
Link: http://lkml.kernel.org/r/1449234426-273049-2-git-send-email-imammedo@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-12-06 12:46:31 +01:00
Borislav Petkov 2d5be37d68 x86/microcode: Initialize the driver late when facilities are up
Running microcode_init() from setup_arch() is a bad idea because
not even kmalloc() is ready at that point and the loader does
all kinds of allocations and init/registration with various
subsystems.

Make it a late initcall when required facilities are initialized
so that the microcode driver initialization can succeed too.

Reported-and-tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20151120112400.GC4028@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-23 10:39:49 +01:00
Krzysztof Mazur 68accac392 x86/setup: Fix low identity map for >= 2GB kernel range
The commit f5f3497cad extended the low identity mapping. However, if
the kernel uses more than 2 GB (VMSPLIT_2G_OPT or VMSPLIT_1G memory
split), the normal memory mapping is overwritten by the low identity
mapping causing a crash. To avoid overwritting, limit the low identity
map to cover only memory before kernel range (PAGE_OFFSET).

Fixes: f5f3497cad "x86/setup: Extend low identity map to cover whole kernel range
Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1446815916-22105-1-git-send-email-krzysiek@podlesie.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-11-07 10:39:40 +01:00
Linus Torvalds b831ef2cad Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RAS changes from Ingo Molnar:
 "The main system reliability related changes were from x86, but also
  some generic RAS changes:

   - AMD MCE error injection subsystem enhancements.  (Aravind
     Gopalakrishnan)

   - Fix MCE and CPU hotplug interaction bug.  (Ashok Raj)

   - kcrash bootup robustness fix.  (Baoquan He)

   - kcrash cleanups.  (Borislav Petkov)

   - x86 microcode driver rework: simplify it by unmodularizing it and
     other cleanups.  (Borislav Petkov)"

* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/mce: Add a default case to the switch in __mcheck_cpu_ancient_init()
  x86/mce: Add a Scalable MCA vendor flags bit
  MAINTAINERS: Unify the microcode driver section
  x86/microcode/intel: Move #ifdef DEBUG inside the function
  x86/microcode/amd: Remove maintainers from comments
  x86/microcode: Remove modularization leftovers
  x86/microcode: Merge the early microcode loader
  x86/microcode: Unmodularize the microcode driver
  x86/mce: Fix thermal throttling reporting after kexec
  kexec/crash: Say which char is the unrecognized
  x86/setup/crash: Check memblock_reserve() retval
  x86/setup/crash: Cleanup some more
  x86/setup/crash: Remove alignment variable
  x86/setup: Cleanup crashkernel reservation functions
  x86/amd_nb, EDAC: Rename amd_get_node_id()
  x86/setup: Do not reserve crashkernel high memory if low reservation failed
  x86/microcode/amd: Do not overwrite final patch levels
  x86/microcode/amd: Extract current patch level read to a function
  x86/ras/mce_amd_inj: Inject bank 4 errors on the NBC
  x86/ras/mce_amd_inj: Trigger deferred and thresholding errors interrupts
  ...
2015-11-03 17:51:33 -08:00
Linus Torvalds f5a8160c1e Merge branch 'core-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI changes from Ingo Molnar:
 "The main changes in this cycle were:

   - further EFI code generalization to make it more workable for ARM64
   - various extensions, such as 64-bit framebuffer address support,
     UEFI v2.5 EFI_PROPERTIES_TABLE support
   - code modularization simplifications and cleanups
   - new debugging parameters
   - various fixes and smaller additions"

* 'core-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  efi: Fix warning of int-to-pointer-cast on x86 32-bit builds
  efi: Use correct type for struct efi_memory_map::phys_map
  x86/efi: Fix kernel panic when CONFIG_DEBUG_VIRTUAL is enabled
  efi: Add "efi_fake_mem" boot option
  x86/efi: Rename print_efi_memmap() to efi_print_memmap()
  efi: Auto-load the efi-pstore module
  efi: Introduce EFI_NX_PE_DATA bit and set it from properties table
  efi: Add support for UEFIv2.5 Properties table
  efi: Add EFI_MEMORY_MORE_RELIABLE support to efi_md_typeattr_format()
  efifb: Add support for 64-bit frame buffer addresses
  efi/arm64: Clean up efi_get_fdt_params() interface
  arm64: Use core efi=debug instead of uefi_debug command line parameter
  efi/x86: Move efi=debug option parsing to core
  drivers/firmware: Make efi/esrt.c driver explicitly non-modular
  efi: Use the generic efi.memmap instead of 'memmap'
  acpi/apei: Use appropriate pgprot_t to map GHES memory
  arm64, acpi/apei: Implement arch_apei_get_mem_attributes()
  arm64/mm: Add PROT_DEVICE_nGnRnE and PROT_NORMAL_WT
  acpi, x86: Implement arch_apei_get_mem_attributes()
  efi, x86: Rearrange efi_mem_attributes()
  ...
2015-11-03 15:05:52 -08:00
Borislav Petkov 9a2bc335f1 x86/microcode: Unmodularize the microcode driver
Make CONFIG_MICROCODE a bool. It was practically a bool already anyway,
since early loader was forcing it to =y.

Regardless, there's no real reason to have something be a module which
gets built-in on the majority of installations out there. And its not
like there's noticeable change in functionality - we still can load late
microcode - just the module glue disappears.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/1445334889-300-2-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-21 11:22:11 +02:00
Borislav Petkov 6f3760570e x86/setup/crash: Check memblock_reserve() retval
memblock_reserve() can fail but the crashkernel reservation code
doesn't check that and this can lead the user into believing
that the crashkernel region was actually reserved. Make sure we
check that return value and we exit early with a failure message
in the error case.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Young <dyoung@redhat.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: WANG Chao <chaowang@redhat.com>
Cc: jerry_hoemann@hp.com
Link: http://lkml.kernel.org/r/1445246268-26285-7-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-21 11:10:56 +02:00
Borislav Petkov f56d55781c x86/setup/crash: Cleanup some more
* Remove unused auto_set variable
* Cleanup local function variable declarations
* Reformat printk string and use pr_info()

No functionality change.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Young <dyoung@redhat.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: WANG Chao <chaowang@redhat.com>
Cc: jerry_hoemann@hp.com
Link: http://lkml.kernel.org/r/1445246268-26285-6-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-21 11:10:56 +02:00
Borislav Petkov 606134f77c x86/setup/crash: Remove alignment variable
Use a macro instead. No functionality change.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Young <dyoung@redhat.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: WANG Chao <chaowang@redhat.com>
Cc: jerry_hoemann@hp.com
Link: http://lkml.kernel.org/r/1445246268-26285-5-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-21 11:10:56 +02:00
Borislav Petkov 97eac21bab x86/setup: Cleanup crashkernel reservation functions
* Shorten variable names
* Realign code, space out for better readability

No code changed:

  # arch/x86/kernel/setup.o:

   text    data     bss     dec     hex filename
   4543    3096   69904   77543   12ee7 setup.o.before
   4543    3096   69904   77543   12ee7 setup.o.after

md5:
   8a1b7c6738a553ca207b56bd84a8f359  setup.o.before.asm
   8a1b7c6738a553ca207b56bd84a8f359  setup.o.after.asm

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Young <dyoung@redhat.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: WANG Chao <chaowang@redhat.com>
Cc: jerry_hoemann@hp.com
Link: http://lkml.kernel.org/r/1445246268-26285-4-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-21 11:10:56 +02:00
Baoquan He eb6db83d10 x86/setup: Do not reserve crashkernel high memory if low reservation failed
People reported that when allocating crashkernel memory using
the ",high" and ",low" syntax, there were cases where the
reservation of the high portion succeeds but the reservation of
the low portion fails.

Then kexec can load the kdump kernel successfully, but booting
the kdump kernel fails as there's no low memory.

The low memory allocation for the kdump kernel can fail on large
systems for a couple of reasons. For example, the manually
specified crashkernel low memory can be too large and thus no
adequate memblock region would be found.

Therefore, we try to reserve low memory for the crash kernel
*after* the high memory portion has been allocated. If that
fails, we free crashkernel high memory too and return. The user
can then take measures accordingly.

Tested-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Baoquan He <bhe@redhat.com>
[ Massage text. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Young <dyoung@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: WANG Chao <chaowang@redhat.com>
Cc: jerry_hoemann@hp.com
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/1445246268-26285-2-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-21 11:10:55 +02:00
Paolo Bonzini f5f3497cad x86/setup: Extend low identity map to cover whole kernel range
On 32-bit systems, the initial_page_table is reused by
efi_call_phys_prolog as an identity map to call
SetVirtualAddressMap.  efi_call_phys_prolog takes care of
converting the current CPU's GDT to a physical address too.

For PAE kernels the identity mapping is achieved by aliasing the
first PDPE for the kernel memory mapping into the first PDPE
of initial_page_table.  This makes the EFI stub's trick "just work".

However, for non-PAE kernels there is no guarantee that the identity
mapping in the initial_page_table extends as far as the GDT; in this
case, accesses to the GDT will cause a page fault (which quickly becomes
a triple fault).  Fix this by copying the kernel mappings from
swapper_pg_dir to initial_page_table twice, both at PAGE_OFFSET and at
identity mapping.

For some reason, this is only reproducible with QEMU's dynamic translation
mode, and not for example with KVM.  However, even under KVM one can clearly
see that the page table is bogus:

    $ qemu-system-i386 -pflash OVMF.fd -M q35 vmlinuz0 -s -S -daemonize
    $ gdb
    (gdb) target remote localhost:1234
    (gdb) hb *0x02858f6f
    Hardware assisted breakpoint 1 at 0x2858f6f
    (gdb) c
    Continuing.

    Breakpoint 1, 0x02858f6f in ?? ()
    (gdb) monitor info registers
    ...
    GDT=     0724e000 000000ff
    IDT=     fffbb000 000007ff
    CR0=0005003b CR2=ff896000 CR3=032b7000 CR4=00000690
    ...

The page directory is sane:

    (gdb) x/4wx 0x32b7000
    0x32b7000:	0x03398063	0x03399063	0x0339a063	0x0339b063
    (gdb) x/4wx 0x3398000
    0x3398000:	0x00000163	0x00001163	0x00002163	0x00003163
    (gdb) x/4wx 0x3399000
    0x3399000:	0x00400003	0x00401003	0x00402003	0x00403003

but our particular page directory entry is empty:

    (gdb) x/1wx 0x32b7000 + (0x724e000 >> 22) * 4
    0x32b7070:	0x00000000

[ It appears that you can skate past this issue if you don't receive
  any interrupts while the bogus GDT pointer is loaded, or if you avoid
  reloading the segment registers in general.

  Andy Lutomirski provides some additional insight:

   "AFAICT it's entirely permissible for the GDTR and/or LDT
    descriptor to point to unmapped memory.  Any attempt to use them
    (segment loads, interrupts, IRET, etc) will try to access that memory
    as if the access came from CPL 0 and, if the access fails, will
    generate a valid page fault with CR2 pointing into the GDT or
    LDT."

  Up until commit 23a0d4e8fa ("efi: Disable interrupts around EFI
  calls, not in the epilog/prolog calls") interrupts were disabled
  around the prolog and epilog calls, and the functional GDT was
  re-installed before interrupts were re-enabled.

  Which explains why no one has hit this issue until now. ]

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reported-by: Laszlo Ersek <lersek@redhat.com>
Cc: <stable@vger.kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
[ Updated changelog. ]
2015-10-16 10:52:29 +01:00
Ingo Molnar 790a2ee242 * Make the EFI System Resource Table (ESRT) driver explicitly
non-modular by ripping out the module_* code since Kconfig doesn't
    allow it to be built as a module anyway - Paul Gortmaker
 
  * Make the x86 efi=debug kernel parameter, which enables EFI debug
    code and output, generic and usable by arm64 - Leif Lindholm
 
  * Add support to the x86 EFI boot stub for 64-bit Graphics Output
    Protocol frame buffer addresses - Matt Fleming
 
  * Detect when the UEFI v2.5 EFI_PROPERTIES_TABLE feature is enabled
    in the firmware and set an efi.flags bit so the kernel knows when
    it can apply more strict runtime mapping attributes - Ard Biesheuvel
 
  * Auto-load the efi-pstore module on EFI systems, just like we
    currently do for the efivars module - Ben Hutchings
 
  * Add "efi_fake_mem" kernel parameter which allows the system's EFI
    memory map to be updated with additional attributes for specific
    memory ranges. This is useful for testing the kernel code that handles
    the EFI_MEMORY_MORE_RELIABLE memmap bit even if your firmware
    doesn't include support - Taku Izumi
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Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into core/efi

Pull v4.4 EFI updates from Matt Fleming:

  - Make the EFI System Resource Table (ESRT) driver explicitly
    non-modular by ripping out the module_* code since Kconfig doesn't
    allow it to be built as a module anyway. (Paul Gortmaker)

  - Make the x86 efi=debug kernel parameter, which enables EFI debug
    code and output, generic and usable by arm64. (Leif Lindholm)

  - Add support to the x86 EFI boot stub for 64-bit Graphics Output
    Protocol frame buffer addresses. (Matt Fleming)

  - Detect when the UEFI v2.5 EFI_PROPERTIES_TABLE feature is enabled
    in the firmware and set an efi.flags bit so the kernel knows when
    it can apply more strict runtime mapping attributes - Ard Biesheuvel

  - Auto-load the efi-pstore module on EFI systems, just like we
    currently do for the efivars module. (Ben Hutchings)

  - Add "efi_fake_mem" kernel parameter which allows the system's EFI
    memory map to be updated with additional attributes for specific
    memory ranges. This is useful for testing the kernel code that handles
    the EFI_MEMORY_MORE_RELIABLE memmap bit even if your firmware
    doesn't include support. (Taku Izumi)

Note: there is a semantic conflict between the following two commits:

  8a53554e12 ("x86/efi: Fix multiple GOP device support")
  ae2ee627dc ("efifb: Add support for 64-bit frame buffer addresses")

I fixed up the interaction in the merge commit, changing the type of
current_fb_base from u32 to u64.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-14 16:51:34 +02:00
Taku Izumi 0f96a99dab efi: Add "efi_fake_mem" boot option
This patch introduces new boot option named "efi_fake_mem".
By specifying this parameter, you can add arbitrary attribute
to specific memory range.
This is useful for debugging of Address Range Mirroring feature.

For example, if "efi_fake_mem=2G@4G:0x10000,2G@0x10a0000000:0x10000"
is specified, the original (firmware provided) EFI memmap will be
updated so that the specified memory regions have
EFI_MEMORY_MORE_RELIABLE attribute (0x10000):

 <original>
   efi: mem36: [Conventional Memory|  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000100000000-0x00000020a0000000) (129536MB)

 <updated>
   efi: mem36: [Conventional Memory|  |MR|  |  |  |   |WB|WT|WC|UC] range=[0x0000000100000000-0x0000000180000000) (2048MB)
   efi: mem37: [Conventional Memory|  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000180000000-0x00000010a0000000) (61952MB)
   efi: mem38: [Conventional Memory|  |MR|  |  |  |   |WB|WT|WC|UC] range=[0x00000010a0000000-0x0000001120000000) (2048MB)
   efi: mem39: [Conventional Memory|  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000001120000000-0x00000020a0000000) (63488MB)

And you will find that the following message is output:

   efi: Memory: 4096M/131455M mirrored memory

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-10-12 14:20:09 +01:00
Dave Young 2965faa5e0 kexec: split kexec_load syscall from kexec core code
There are two kexec load syscalls, kexec_load another and kexec_file_load.
 kexec_file_load has been splited as kernel/kexec_file.c.  In this patch I
split kexec_load syscall code to kernel/kexec.c.

And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and
use kexec_file_load only, or vice verse.

The original requirement is from Ted Ts'o, he want kexec kernel signature
being checked with CONFIG_KEXEC_VERIFY_SIG enabled.  But kexec-tools use
kexec_load syscall can bypass the checking.

Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel.  KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.

Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig.  Also updated general kernel code with to
kexec_load syscall.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Petr Tesarik <ptesarik@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10 13:29:01 -07:00
Mark Salter 5dd2c4bded x86: use generic early mem copy
The early_ioremap library now has a generic copy_from_early_mem()
function.  Use the generic copy function for x86 relocate_initrd().

[akpm@linux-foundation.org: remove MAX_MAP_CHUNK define, per Yinghai Lu]
Signed-off-by: Mark Salter <msalter@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08 15:35:28 -07:00
Paolo Pisati 949163015c x86/boot: Obsolete the MCA sys_desc_table
The kernel does not support the MCA bus anymroe, so mark sys_desc_table
as obsolete: remove any reference from the code together with the remaining
of MCA logic.

bloat-o-meter output:

  add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-55 (-55)
  function                                     old     new   delta
  i386_start_kernel                            128     119      -9
  setup_arch                                  1421    1375     -46

Signed-off-by: Paolo Pisati <p.pisati@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.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/1437409430-8491-1-git-send-email-p.pisati@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-21 10:55:11 +02:00
Linus Torvalds b1be9ead13 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Two FPU rewrite related fixes.  This addresses all known x86
  regressions at this stage.  Also some other misc fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu: Fix boot crash in the early FPU code
  x86/asm/entry/64: Update path names
  x86/fpu: Fix FPU related boot regression when CPUID masking BIOS feature is enabled
  x86/boot/setup: Clean up the e820_reserve_setup_data() code
  x86/kaslr: Fix typo in the KASLR_FLAG documentation
2015-07-04 08:58:50 -07:00
Ingo Molnar dc5fb575df Merge branch 'x86/boot' into x86/urgent
Merge branch that got ready.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-30 07:57:04 +02:00