Commit Graph

526 Commits

Author SHA1 Message Date
Linus Torvalds 7d2b6ef19c ARM: SoC driver updates for v4.1
Driver updates for v4.1. Some of these are for drivers/soc, where we find more
 and more SoC-specific drivers these days. Some are for other driver subsystems
 where we have received acks from the appropriate maintainers.
 
 The larger parts of this branch are:
 
 - MediaTek support for their PMIC wrapper interface, a high-level interface
   for talking to the system PMIC over a dedicated I2C interface.
 - Qualcomm SCM driver has been moved to drivers/firmware. It's used for CPU
   up/down and needs to be in a shared location for arm/arm64 common code.
 - Cleanup of ARM-CCI PMU code.
 - Anoter set of cleanusp to the OMAP GPMC code.
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Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC driver updates from Olof Johansson:
 "Driver updates for v4.1.  Some of these are for drivers/soc, where we
  find more and more SoC-specific drivers these days.  Some are for
  other driver subsystems where we have received acks from the
  appropriate maintainers.

  The larger parts of this branch are:

   - MediaTek support for their PMIC wrapper interface, a high-level
     interface for talking to the system PMIC over a dedicated I2C
     interface.

   - Qualcomm SCM driver has been moved to drivers/firmware.  It's used
     for CPU up/down and needs to be in a shared location for arm/arm64
     common code.

   - cleanup of ARM-CCI PMU code.

   - another set of cleanusp to the OMAP GPMC code"

* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (43 commits)
  soc/mediatek: Remove unused variables
  clocksource: atmel-st: select MFD_SYSCON
  soc: mediatek: Add PMIC wrapper for MT8135 and MT8173 SoCs
  arm-cci: Fix CCI PMU event validation
  arm-cci: Split the code for PMU vs driver support
  arm-cci: Get rid of secure transactions for PMU driver
  arm-cci: Abstract the CCI400 PMU specific definitions
  arm-cci: Rearrange code for splitting PMU vs driver code
  drivers: cci: reject groups spanning multiple HW PMUs
  ARM: at91: remove useless include
  clocksource: atmel-st: remove mach/hardware dependency
  clocksource: atmel-st: use syscon/regmap
  ARM: at91: time: move the system timer driver to drivers/clocksource
  ARM: at91: properly initialize timer
  ARM: at91: at91rm9200: remove deprecated arm_pm_restart
  watchdog: at91rm9200: implement restart handler
  watchdog: at91rm9200: use the system timer syscon
  mfd: syscon: Add atmel system timer registers definition
  ARM: at91/dt: declare atmel,at91rm9200-st as a syscon
  soc: qcom: gsbi: Add support for ADM CRCI muxing
  ...
2015-04-22 09:18:17 -07:00
Linus Torvalds 41d5e08ea8 TTY/Serial patches for 4.1-rc1
Here's the big tty/serial driver update for 4.1-rc1.
 
 It was delayed for a bit due to some questions surrounding some of the
 console command line parsing changes that are in here.  There's still
 one tiny regression for people who were previously putting multiple
 console command lines and expecting them all to be ignored for some odd
 reason, but Peter is working on fixing that.  If not, I'll send a revert
 for the offending patch, but I have faith that Peter can address it.
 
 Other than the console work here, there's the usual serial driver
 updates and changes, and a buch of 8250 reworks to try to make that
 driver easier to maintain over time, and have it support more devices in
 the future.
 
 All of these have been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here's the big tty/serial driver update for 4.1-rc1.

  It was delayed for a bit due to some questions surrounding some of the
  console command line parsing changes that are in here.  There's still
  one tiny regression for people who were previously putting multiple
  console command lines and expecting them all to be ignored for some
  odd reason, but Peter is working on fixing that.  If not, I'll send a
  revert for the offending patch, but I have faith that Peter can
  address it.

  Other than the console work here, there's the usual serial driver
  updates and changes, and a buch of 8250 reworks to try to make that
  driver easier to maintain over time, and have it support more devices
  in the future.

  All of these have been in linux-next for a while"

* tag 'tty-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (119 commits)
  n_gsm: Drop unneeded cast on netdev_priv
  sc16is7xx: expose RTS inversion in RS-485 mode
  serial: 8250_pci: port failed after wakeup from S3
  earlycon: 8250: Document kernel command line options
  earlycon: 8250: Fix command line regression
  earlycon: Fix __earlycon_table stride
  tty: clean up the tty time logic a bit
  serial: 8250_dw: only get the clock rate in one place
  serial: 8250_dw: remove useless ACPI ID check
  dmaengine: hsu: move memory allocation to GFP_NOWAIT
  dmaengine: hsu: remove redundant pieces of code
  serial: 8250_pci: add Intel Tangier support
  dmaengine: hsu: add Intel Tangier PCI ID
  serial: 8250_pci: replace switch-case by formula for Intel MID
  serial: 8250_pci: replace switch-case by formula
  tty: cpm_uart: replace CONFIG_8xx by CONFIG_CPM1
  serial: jsm: some off by one bugs
  serial: xuartps: Fix check in console_setup().
  serial: xuartps: Get rid of register access macros.
  serial: xuartps: Fix iobase use.
  ...
2015-04-21 09:33:10 -07:00
Linus Torvalds 9c65e12a55 Merge branch 'core-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI update from Ingo Molnar:
 "This tree includes various fixes, cleanups, a new efi=debug boot
  option and EFI boot stub memory allocation optimizations"

* 'core-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/libstub: Retrieve FDT size when loaded from UEFI config table
  efi: Clean up the efi_call_phys_[prolog|epilog]() save/restore interaction
  efi: Disable interrupts around EFI calls, not in the epilog/prolog calls
  x86/efi: Add a "debug" option to the efi= cmdline
  firmware: dmi_scan: Use direct access to static vars
  firmware: dmi_scan: Use full dmi version for SMBIOS3
2015-04-13 10:22:30 -07:00
Greg Kroah-Hartman b3e3bf2ef2 Merge 4.0-rc7 into tty-next
We want the fixes in here as well, also to help out with merge issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-07 11:07:20 +02:00
Olof Johansson 47f36e4921 CCI-400 PMU updates
This series reworks some of the CCI-400 PMU code so that it can be used
 on both ARM and ARM64-based systems, without the need to boot in secure
 mode on the latter. This paves the way for CCI-500 support in future.
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Merge tag 'arm-perf-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into next/drivers

Merge "arm-cci PMU updates for 4.1" from Will Deacon:

CCI-400 PMU updates

This series reworks some of the CCI-400 PMU code so that it can be used
on both ARM and ARM64-based systems, without the need to boot in secure
mode on the latter. This paves the way for CCI-500 support in future.

* tag 'arm-perf-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux:
  arm-cci: Fix CCI PMU event validation
  arm-cci: Split the code for PMU vs driver support
  arm-cci: Get rid of secure transactions for PMU driver
  arm-cci: Abstract the CCI400 PMU specific definitions
  arm-cci: Rearrange code for splitting PMU vs driver code
  drivers: cci: reject groups spanning multiple HW PMUs
  + Linux 4.0-rc4

Signed-off-by: Olof Johansson <olof@lixom.net>
2015-04-03 13:38:43 -07:00
Ard Biesheuvel a643375f4b efi/libstub: Retrieve FDT size when loaded from UEFI config table
When allocating memory for the copy of the FDT that the stub
modifies and passes to the kernel, it uses the current size as
an estimate of how much memory to allocate, and increases it page
by page if it turns out to be too small. However, when loading
the FDT from a UEFI configuration table, the estimated size is
left at its default value of zero, and the allocation loop runs
starting from zero all the way up to the allocation size that
finally fits the updated FDT.

Instead, retrieve the size of the FDT from the FDT header when
loading it from the UEFI config table.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Roy Franz <roy.franz@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-04-01 12:46:23 +01:00
Ingo Molnar 36cbf25dc7 * Fix integer overflow issue in the DMI SMBIOS 3.0 code when
calculating the number of DMI table entries - Jean Delvare
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Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent

Pull EFI fix from Matt Fleming:

  - Fix integer overflow issue in the DMI SMBIOS 3.0 code when
    calculating the number of DMI table entries. (Jean Delvare)

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-31 10:45:47 +02:00
Jean Delvare bfbaafae85 firmware: dmi_scan: Prevent dmi_num integer overflow
dmi_num is a u16, dmi_len is a u32, so this construct:

	dmi_num = dmi_len / 4;

would result in an integer overflow for a DMI table larger than
256 kB. I've never see such a large table so far, but SMBIOS 3.0
makes it possible so maybe we'll see such tables in the future.

So instead of faking a structure count when the entry point does
not provide it, adjust the loop condition in dmi_table() to properly
deal with the case where dmi_num is not set.

This bug was introduced with the initial SMBIOS 3.0 support in commit
fc43026278 ("dmi: add support for SMBIOS 3.0 64-bit entry point").

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Cc: <stable@vger.kernel.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-03-27 10:53:46 +00:00
Peter Hurley df519e7bd3 serial: 8250_early: Remove setup_early_serial8250_console()
setup_earlycon() will now match and register the desired earlycon
from the param string (as if 'earlycon=...' had been set on the
command line). Use setup_earlycon() from existing arch call sites
which start an earlycon directly.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26 17:25:27 +01:00
Ivan Khoronzhuk 552e19d876 firmware: dmi_scan: Use direct access to static vars
There is no reason to pass static vars to function that can use
only them.

The dmi_table() can use only dmi_len and dmi_num static vars, so use
them directly. In this case we can freely change their type in one
place and slightly decrease redundancy.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-03-26 14:00:15 +00:00
Ivan Khoronzhuk 95be58df74 firmware: dmi_scan: Use full dmi version for SMBIOS3
New SMBIOS3 spec adds additional field for versioning - docrev.
The docrev identifies the revision of a specification implemented in
the table structures, so display SMBIOSv3 versions in format,
like "3.22.1".

In case of only 32 bit entry point for versions > 3 display
dmi version like "3.22.x" as we don't know the docrev.

In other cases display version like it was.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-03-26 13:48:15 +00:00
Lina Iyer 767b0235dd firmware: qcom: scm: Support cpu power down through SCM
Support powering down the calling cpu, by trapping into SCM. This
termination function triggers the ARM cpu to execute WFI instruction,
causing the power controller to safely power the cpu down.

Caches may be flushed before powering down the cpu. If cache controller
is set to turn off when the cpu is powered down, then the flags argument
indicates to the secure mode to flush its cache lines before executing
WFI.The warm boot reset address for the cpu should be set before the
calling into this function for the cpu to resume.

The original code for the qcom_scm_call_atomic1() comes from a patch by
Stephen Boyd [1]. The function scm_call_atomic1() has been cherry picked
and renamed to match the convention used in this file. Since there are
no users of scm_call_atomic2(), the function is not included.

[1]. https://lkml.org/lkml/2014/8/4/765

Signed-off-by: Stephen Boyd <sboyd@codeauraro.org>
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Kumar Gala <galak@codeaurora.org>
2015-03-11 15:15:11 -05:00
Lina Iyer 2ce76a6ad3 firmware: qcom: scm: Add qcom_scm_set_warm_boot_addr function
A core can be powered down for cpuidle or when it is hotplugged off. In
either case, the warmboot return address would be different. Allow
setting the warmboot address for a specific cpu, optimize and write to
the firmware, if the address is different than the previously set
address.

Export qcom_scm_set_warm_boot_addr function move the warm boot flags to
implementation.

Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Kumar Gala <galak@codeaurora.org>
2015-03-11 15:15:07 -05:00
Lina Iyer a353e4a06f firmware: qcom: scm: Clean cold boot entry to export only the API
We dont need to export the SCM specific cold boot flags to the platform
code. Export only a function to set the cold boot address.

Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Kumar Gala <galak@codeaurora.org>
2015-03-11 15:15:05 -05:00
Kumar Gala 916f743da3 firmware: qcom: scm: Move the scm driver to drivers/firmware
Architectural changes in the ARM Linux kernel tree mandate the eventual
removal of the mach-* directories. Move the scm driver to
drivers/firmware and the scm header to include/linux to support that
removal.

Signed-off-by: Kumar Gala <galak@codeaurora.org>
2015-03-11 15:06:38 -05:00
Ingo Molnar be482d624c * Fix regression in DMI sysfs code for handling "End of Table" entry
and a type bug that could lead to integer overflow - Ivan Khoronzhuk
 
  * Fix boundary checking in efi_high_alloc() which can lead to memory
    corruption in the EFI boot stubs - Yinghai Lu
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Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent

Pull EFI fixes from Matt Fleming:

" - Fix regression in DMI sysfs code for handling "End of Table" entry
    and a type bug that could lead to integer overflow. (Ivan Khoronzhuk)

  - Fix boundary checking in efi_high_alloc() which can lead to memory
    corruption in the EFI boot stubs. (Yinghai Lu)"

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-02 14:18:57 +01:00
Ivan Khoronzhuk 6d9ff47331 firmware: dmi_scan: Fix dmi_len type
According to SMBIOSv3 specification the length of DMI table can be
up to 32bits wide. So use appropriate type to avoid overflow.

It's obvious that dmi_num theoretically can be more than u16 also,
so it's can be changed to u32 or at least it's better to use int
instead of u16, but on that moment I cannot imagine dmi structure
count more than 65535 and it can require changing type of vars that
work with it. So I didn't correct it.

Acked-by: Ard Biesheuvel <ard@linaro.org>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-02-24 18:54:17 +00:00
Yinghai Lu 7ed620bb34 efi/libstub: Fix boundary checking in efi_high_alloc()
While adding support loading kernel and initrd above 4G to grub2 in legacy
mode, I was referring to efi_high_alloc().
That will allocate buffer for kernel and then initrd, and initrd will
use kernel buffer start as limit.

During testing found two buffers will be overlapped when initrd size is
very big like 400M.

It turns out efi_high_alloc() boundary checking is not right.
end - size will be the new start, and should not compare new
start with max, we need to make sure end is smaller than max.

[ Basically, with the current efi_high_alloc() code it's possible to
  allocate memory above 'max', because efi_high_alloc() doesn't check
  that the tail of the allocation is below 'max'.

  If you have an EFI memory map with a single entry that looks like so,

   [0xc0000000-0xc0004000]

  And want to allocate 0x3000 bytes below 0xc0003000 the current code
  will allocate [0xc0001000-0xc0004000], not [0xc0000000-0xc0003000]
  like you would expect. - Matt ]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-02-24 18:46:03 +00:00
Linus Torvalds 5fbe4c224c Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc x86 fixes from Ingo Molnar:
 "This contains:

   - EFI fixes
   - a boot printout fix
   - ASLR/kASLR fixes
   - intel microcode driver fixes
   - other misc fixes

  Most of the linecount comes from an EFI revert"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/ASLR: Avoid PAGE_SIZE redefinition for UML subarch
  x86/microcode/intel: Handle truncated microcode images more robustly
  x86/microcode/intel: Guard against stack overflow in the loader
  x86, mm/ASLR: Fix stack randomization on 64-bit systems
  x86/mm/init: Fix incorrect page size in init_memory_mapping() printks
  x86/mm/ASLR: Propagate base load address calculation
  Documentation/x86: Fix path in zero-page.txt
  x86/apic: Fix the devicetree build in certain configs
  Revert "efi/libstub: Call get_memory_map() to obtain map and desc sizes"
  x86/efi: Avoid triple faults during EFI mixed mode calls
2015-02-21 10:41:29 -08:00
Ivan Khoronzhuk ce204e9a4b firmware: dmi_scan: Fix dmi scan to handle "End of Table" structure
The dmi-sysfs should create "End of Table" entry, that is type 127. But
after adding initial SMBIOS v3 support fc43026278 ("dmi: add support
for SMBIOS 3.0 64-bit entry point") the 127-0 entry is not handled any
more, as result it's not created in dmi sysfs for instance. This is
important because the size of whole DMI table must correspond to sum of
all DMI entry sizes.

So move the end-of-table check after it's handled by dmi_table.

Reviewed-by: Ard Biesheuvel <ard@linaro.org>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Cc: <stable@vger.kernel.org> # v3.19
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-02-18 14:47:30 +00:00
Matt Fleming 43a9f69692 Revert "efi/libstub: Call get_memory_map() to obtain map and desc sizes"
This reverts commit d1a8d66b91.

Ard reported a boot failure when running UEFI under Qemu and Xen and
experimenting with various Tianocore build options,

 "As it turns out, when allocating room for the UEFI memory map using
  UEFI's AllocatePool (), it may result in two new memory map entries
  being created, for instance, when using Tianocore's preallocated region
  feature. For example, the following region

  0x00005ead5000-0x00005ebfffff [Conventional Memory|   |  |  |  |  |WB|WT|WC|UC]

  may be split like this

  0x00005ead5000-0x00005eae2fff [Conventional Memory|   |  |  |  |  |WB|WT|WC|UC]
  0x00005eae3000-0x00005eae4fff [Loader Data        |   |  |  |  |  |WB|WT|WC|UC]
  0x00005eae5000-0x00005ebfffff [Conventional Memory|   |  |  |  |  |WB|WT|WC|UC]

  if the preallocated Loader Data region was chosen to be right in the
  middle of the original free space.

  After patch d1a8d66b91 ("efi/libstub: Call get_memory_map() to
  obtain map and desc sizes"), this is not being dealt with correctly
  anymore, as the existing logic to allocate room for a single additional
  entry has become insufficient."

Mark requested to reinstate the old loop we had before commit
d1a8d66b91, which grows the memory map buffer until it's big enough to
hold the EFI memory map.

Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-02-18 11:38:13 +00:00
Andrey Ryabinin 393f203f5f x86_64: kasan: add interceptors for memset/memmove/memcpy functions
Recently instrumentation of builtin functions calls was removed from GCC
5.0.  To check the memory accessed by such functions, userspace asan
always uses interceptors for them.

So now we should do this as well.  This patch declares
memset/memmove/memcpy as weak symbols.  In mm/kasan/kasan.c we have our
own implementation of those functions which checks memory before accessing
it.

Default memset/memmove/memcpy now now always have aliases with '__'
prefix.  For files that built without kasan instrumentation (e.g.
mm/slub.c) original mem* replaced (via #define) with prefixed variants,
cause we don't want to check memory accesses there.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:41 -08:00
Andrey Ryabinin 0b24becc81 kasan: add kernel address sanitizer infrastructure
Kernel Address sanitizer (KASan) is a dynamic memory error detector.  It
provides fast and comprehensive solution for finding use-after-free and
out-of-bounds bugs.

KASAN uses compile-time instrumentation for checking every memory access,
therefore GCC > v4.9.2 required.  v4.9.2 almost works, but has issues with
putting symbol aliases into the wrong section, which breaks kasan
instrumentation of globals.

This patch only adds infrastructure for kernel address sanitizer.  It's
not available for use yet.  The idea and some code was borrowed from [1].

Basic idea:

The main idea of KASAN is to use shadow memory to record whether each byte
of memory is safe to access or not, and use compiler's instrumentation to
check the shadow memory on each memory access.

Address sanitizer uses 1/8 of the memory addressable in kernel for shadow
memory and uses direct mapping with a scale and offset to translate a
memory address to its corresponding shadow address.

Here is function to translate address to corresponding shadow address:

     unsigned long kasan_mem_to_shadow(unsigned long addr)
     {
                return (addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET;
     }

where KASAN_SHADOW_SCALE_SHIFT = 3.

So for every 8 bytes there is one corresponding byte of shadow memory.
The following encoding used for each shadow byte: 0 means that all 8 bytes
of the corresponding memory region are valid for access; k (1 <= k <= 7)
means that the first k bytes are valid for access, and other (8 - k) bytes
are not; Any negative value indicates that the entire 8-bytes are
inaccessible.  Different negative values used to distinguish between
different kinds of inaccessible memory (redzones, freed memory) (see
mm/kasan/kasan.h).

To be able to detect accesses to bad memory we need a special compiler.
Such compiler inserts a specific function calls (__asan_load*(addr),
__asan_store*(addr)) before each memory access of size 1, 2, 4, 8 or 16.

These functions check whether memory region is valid to access or not by
checking corresponding shadow memory.  If access is not valid an error
printed.

Historical background of the address sanitizer from Dmitry Vyukov:

	"We've developed the set of tools, AddressSanitizer (Asan),
	ThreadSanitizer and MemorySanitizer, for user space. We actively use
	them for testing inside of Google (continuous testing, fuzzing,
	running prod services). To date the tools have found more than 10'000
	scary bugs in Chromium, Google internal codebase and various
	open-source projects (Firefox, OpenSSL, gcc, clang, ffmpeg, MySQL and
	lots of others): [2] [3] [4].
	The tools are part of both gcc and clang compilers.

	We have not yet done massive testing under the Kernel AddressSanitizer
	(it's kind of chicken and egg problem, you need it to be upstream to
	start applying it extensively). To date it has found about 50 bugs.
	Bugs that we've found in upstream kernel are listed in [5].
	We've also found ~20 bugs in out internal version of the kernel. Also
	people from Samsung and Oracle have found some.

	[...]

	As others noted, the main feature of AddressSanitizer is its
	performance due to inline compiler instrumentation and simple linear
	shadow memory. User-space Asan has ~2x slowdown on computational
	programs and ~2x memory consumption increase. Taking into account that
	kernel usually consumes only small fraction of CPU and memory when
	running real user-space programs, I would expect that kernel Asan will
	have ~10-30% slowdown and similar memory consumption increase (when we
	finish all tuning).

	I agree that Asan can well replace kmemcheck. We have plans to start
	working on Kernel MemorySanitizer that finds uses of unitialized
	memory. Asan+Msan will provide feature-parity with kmemcheck. As
	others noted, Asan will unlikely replace debug slab and pagealloc that
	can be enabled at runtime. Asan uses compiler instrumentation, so even
	if it is disabled, it still incurs visible overheads.

	Asan technology is easily portable to other architectures. Compiler
	instrumentation is fully portable. Runtime has some arch-dependent
	parts like shadow mapping and atomic operation interception. They are
	relatively easy to port."

Comparison with other debugging features:
========================================

KMEMCHECK:

  - KASan can do almost everything that kmemcheck can.  KASan uses
    compile-time instrumentation, which makes it significantly faster than
    kmemcheck.  The only advantage of kmemcheck over KASan is detection of
    uninitialized memory reads.

    Some brief performance testing showed that kasan could be
    x500-x600 times faster than kmemcheck:

$ netperf -l 30
		MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to localhost (127.0.0.1) port 0 AF_INET
		Recv   Send    Send
		Socket Socket  Message  Elapsed
		Size   Size    Size     Time     Throughput
		bytes  bytes   bytes    secs.    10^6bits/sec

no debug:	87380  16384  16384    30.00    41624.72

kasan inline:	87380  16384  16384    30.00    12870.54

kasan outline:	87380  16384  16384    30.00    10586.39

kmemcheck: 	87380  16384  16384    30.03      20.23

  - Also kmemcheck couldn't work on several CPUs.  It always sets
    number of CPUs to 1.  KASan doesn't have such limitation.

DEBUG_PAGEALLOC:
	- KASan is slower than DEBUG_PAGEALLOC, but KASan works on sub-page
	  granularity level, so it able to find more bugs.

SLUB_DEBUG (poisoning, redzones):
	- SLUB_DEBUG has lower overhead than KASan.

	- SLUB_DEBUG in most cases are not able to detect bad reads,
	  KASan able to detect both reads and writes.

	- In some cases (e.g. redzone overwritten) SLUB_DEBUG detect
	  bugs only on allocation/freeing of object. KASan catch
	  bugs right before it will happen, so we always know exact
	  place of first bad read/write.

[1] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel
[2] https://code.google.com/p/address-sanitizer/wiki/FoundBugs
[3] https://code.google.com/p/thread-sanitizer/wiki/FoundBugs
[4] https://code.google.com/p/memory-sanitizer/wiki/FoundBugs
[5] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel#Trophies

Based on work by Andrey Konovalov.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Acked-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:40 -08:00
Linus Torvalds 6b00f7efb5 arm64 updates for 3.20:
- reimplementation of the virtual remapping of UEFI Runtime Services in
   a way that is stable across kexec
 - emulation of the "setend" instruction for 32-bit tasks (user
   endianness switching trapped in the kernel, SCTLR_EL1.E0E bit set
   accordingly)
 - compat_sys_call_table implemented in C (from asm) and made it a
   constant array together with sys_call_table
 - export CPU cache information via /sys (like other architectures)
 - DMA API implementation clean-up in preparation for IOMMU support
 - macros clean-up for KVM
 - dropped some unnecessary cache+tlb maintenance
 - CONFIG_ARM64_CPU_SUSPEND clean-up
 - defconfig update (CPU_IDLE)
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:
 "arm64 updates for 3.20:

   - reimplementation of the virtual remapping of UEFI Runtime Services
     in a way that is stable across kexec
   - emulation of the "setend" instruction for 32-bit tasks (user
     endianness switching trapped in the kernel, SCTLR_EL1.E0E bit set
     accordingly)
   - compat_sys_call_table implemented in C (from asm) and made it a
     constant array together with sys_call_table
   - export CPU cache information via /sys (like other architectures)
   - DMA API implementation clean-up in preparation for IOMMU support
   - macros clean-up for KVM
   - dropped some unnecessary cache+tlb maintenance
   - CONFIG_ARM64_CPU_SUSPEND clean-up
   - defconfig update (CPU_IDLE)

  The EFI changes going via the arm64 tree have been acked by Matt
  Fleming.  There is also a patch adding sys_*stat64 prototypes to
  include/linux/syscalls.h, acked by Andrew Morton"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (47 commits)
  arm64: compat: Remove incorrect comment in compat_siginfo
  arm64: Fix section mismatch on alloc_init_p[mu]d()
  arm64: Avoid breakage caused by .altmacro in fpsimd save/restore macros
  arm64: mm: use *_sect to check for section maps
  arm64: drop unnecessary cache+tlb maintenance
  arm64:mm: free the useless initial page table
  arm64: Enable CPU_IDLE in defconfig
  arm64: kernel: remove ARM64_CPU_SUSPEND config option
  arm64: make sys_call_table const
  arm64: Remove asm/syscalls.h
  arm64: Implement the compat_sys_call_table in C
  syscalls: Declare sys_*stat64 prototypes if __ARCH_WANT_(COMPAT_)STAT64
  compat: Declare compat_sys_sigpending and compat_sys_sigprocmask prototypes
  arm64: uapi: expose our struct ucontext to the uapi headers
  smp, ARM64: Kill SMP single function call interrupt
  arm64: Emulate SETEND for AArch32 tasks
  arm64: Consolidate hotplug notifier for instruction emulation
  arm64: Track system support for mixed endian EL0
  arm64: implement generic IOMMU configuration
  arm64: Combine coherent and non-coherent swiotlb dma_ops
  ...
2015-02-11 18:03:54 -08:00
Ingo Molnar 3c01b74e81 * Move efivarfs from the misc filesystem section to pseudo filesystem,
since that's a more logical and accurate place - Leif Lindholm
 
  * Update efibootmgr URL in Kconfig help - Peter Jones
 
  * Improve accuracy of EFI guid function names - Borislav Petkov
 
  * Expose firmware platform size in sysfs for the benefit of EFI boot
    loader installers and other utilities - Steve McIntyre
 
  * Cleanup __init annotations for arm64/efi code - Ard Biesheuvel
 
  * Mark the UIE as unsupported for rtc-efi - Ard Biesheuvel
 
  * Fix memory leak in error code path of runtime map code - Dan Carpenter
 
  * Improve robustness of get_memory_map() by removing assumptions on the
    size of efi_memory_desc_t (which could change in future spec
    versions) and querying the firmware instead of guessing about the
    memmap size - Ard Biesheuvel
 
  * Remove superfluous guid unparse calls - Ivan Khoronzhuk
 
  * Delete unnecessary chosen@0 DT node FDT code since was duplicated
    from code in drivers/of and is entirely unnecessary - Leif Lindholm
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Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/efi

Pull EFI updates from Matt Fleming:

" - Move efivarfs from the misc filesystem section to pseudo filesystem,
    since that's a more logical and accurate place - Leif Lindholm

  - Update efibootmgr URL in Kconfig help - Peter Jones

  - Improve accuracy of EFI guid function names - Borislav Petkov

  - Expose firmware platform size in sysfs for the benefit of EFI boot
    loader installers and other utilities - Steve McIntyre

  - Cleanup __init annotations for arm64/efi code - Ard Biesheuvel

  - Mark the UIE as unsupported for rtc-efi - Ard Biesheuvel

  - Fix memory leak in error code path of runtime map code - Dan Carpenter

  - Improve robustness of get_memory_map() by removing assumptions on the
    size of efi_memory_desc_t (which could change in future spec
    versions) and querying the firmware instead of guessing about the
    memmap size - Ard Biesheuvel

  - Remove superfluous guid unparse calls - Ivan Khoronzhuk

  - Delete unnecessary chosen@0 DT node FDT code since was duplicated
    from code in drivers/of and is entirely unnecessary - Leif Lindholm

   There's nothing super scary, mainly cleanups, and a merge from Ricardo who
   kindly picked up some patches from the linux-efi mailing list while I
   was out on annual leave in December.

   Perhaps the biggest risk is the get_memory_map() change from Ard, which
   changes the way that both the arm64 and x86 EFI boot stub build the
   early memory map. It would be good to have it bake in linux-next for a
   while.
"

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-29 19:16:40 +01:00
Leif Lindholm 1162930504 efi: Don't look for chosen@0 node on DT platforms
Due to some scary special case handling noticed in drivers/of, various
bits of the ARM* EFI support patches did duplicate looking for @0
variants of various nodes. Unless on an ancient PPC system, these are
not in fact required. Most instances have become refactored out along
the way, this removes the last one.

Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-01-20 22:41:56 +00:00
Ivan Khoronzhuk 613782b087 firmware: efi: Remove unneeded guid unparse
There is no reason to translate guid number to string here.
So remove it in order to not do unneeded work.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-01-20 22:29:31 +00:00
Ard Biesheuvel d1a8d66b91 efi/libstub: Call get_memory_map() to obtain map and desc sizes
This fixes two minor issues in the implementation of get_memory_map():
- Currently, it assumes that sizeof(efi_memory_desc_t) == desc_size,
  which is usually true, but not mandated by the spec. (This was added
  intentionally to allow future additions to the definition of
  efi_memory_desc_t). The way the loop is implemented currently, the
  added slack space may be insufficient if desc_size is larger, which in
  some corner cases could result in the loop never terminating.
- It allocates 32 efi_memory_desc_t entries first (again, using the size
  of the struct instead of desc_size), and frees and reallocates if it
  turns out to be insufficient. Few implementations of UEFI have such small
  memory maps, which results in a unnecessary allocate/free pair on each
  invocation.

Fix this by calling the get_memory_map() boot service first with a '0'
input value for map size to retrieve the map size and desc size from the
firmware and only then perform the allocation, using desc_size rather
than sizeof(efi_memory_desc_t).

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-01-20 22:13:33 +00:00
Dan Carpenter 86d68a58d0 efi: Small leak on error in runtime map code
The "> 0" here should ">= 0" so we free map_entries[0].

Fixes: 926172d460 ('efi: Export EFI runtime memory mapping to sysfs')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-01-20 15:50:25 +00:00
Ard Biesheuvel ddeeefe2df arm64/efi: efistub: Apply __init annotation
This ensures all stub component are freed when the kernel proper is
done booting, by prefixing the names of all ELF sections that have
the SHF_ALLOC attribute with ".init". This approach ensures that even
implicitly emitted allocated data (like initializer values and string
literals) are covered.

At the same time, remove some __init annotations in the stub that have
now become redundant, and add the __init annotation to handle_kernel_image
which will now trigger a section mismatch warning without it.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-01-15 21:28:35 +00:00
Ard Biesheuvel f3cdfd239d arm64/efi: move SetVirtualAddressMap() to UEFI stub
In order to support kexec, the kernel needs to be able to deal with the
state of the UEFI firmware after SetVirtualAddressMap() has been called.
To avoid having separate code paths for non-kexec and kexec, let's move
the call to SetVirtualAddressMap() to the stub: this will guarantee us
that it will only be called once (since the stub is not executed during
kexec), and ensures that the UEFI state is identical between kexec and
normal boot.

This implies that the layout of the virtual mapping needs to be created
by the stub as well. All regions are rounded up to a naturally aligned
multiple of 64 KB (for compatibility with 64k pages kernels) and recorded
in the UEFI memory map. The kernel proper reads those values and installs
the mappings in a dedicated set of page tables that are swapped in during
UEFI Runtime Services calls.

Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Matt Fleming <matt.fleming@intel.com>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2015-01-12 16:29:12 +00:00
Steve McIntyre 2859dff97e efi: Expose underlying UEFI firmware platform size to userland
In some cases (e.g. Intel Bay Trail machines), the kernel will happily
run in 64-bit even if the underlying UEFI firmware platform is
32-bit. That's great, but it's difficult for userland utilities like
grub-install to do the right thing in such a situation.

The kernel already knows about the size of the firmware via
efi_enabled(EFI_64BIT). Add an extra sysfs interface
/sys/firmware/efi/fw_platform_size to expose that information to
userland for low-level utilities to use.

Signed-off-by: Steve McIntyre <steve@einval.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-01-12 11:51:32 +00:00
Ard Biesheuvel cf2b0f102c efi: efistub: allow allocation alignment larger than EFI_PAGE_SIZE
On systems with 64 KB pages, it is preferable for UEFI memory map
entries to be 64 KB aligned multiples of 64 KB, because it relieves
us of having to deal with the residues.
So, if EFI_ALLOC_ALIGN is #define'd by the platform, use it to round
up all memory allocations made.

Acked-by: Matt Fleming <matt.fleming@intel.com>
Acked-by: Borislav Petkov <bp@suse.de>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2015-01-12 08:17:00 +00:00
Ard Biesheuvel 7bb68410ef efi: split off remapping code from efi_config_init()
Split of the remapping code from efi_config_init() so that the caller
can perform its own remapping. This is necessary to correctly handle
virtually remapped UEFI memory regions under kexec, as efi.systab will
have been updated to a virtual address.

Acked-by: Matt Fleming <matt.fleming@intel.com>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2015-01-12 08:16:55 +00:00
Borislav Petkov 26e022727f efi: Rename efi_guid_unparse to efi_guid_to_str
Call it what it does - "unparse" is plain-misleading.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
2015-01-07 19:07:44 -08:00
Peter Jones 0e4ca02b3f efi: Update the URLs for efibootmgr
Matt Domsch changed the dell page to point to the new upstream quite
some time ago; kernel should reflect that here as well.

Cc: Matt Domsch <Matt_Domsch@dell.com>
Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
2015-01-07 19:06:28 -08:00
Linus Torvalds e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00
Linus Torvalds 1dd7dcb6ea There was a lot of clean ups and minor fixes. One of those clean ups was
to the trace_seq code. It also removed the return values to the
 trace_seq_*() functions and use trace_seq_has_overflowed() to see if
 the buffer filled up or not. This is similar to work being done to the
 seq_file code as well in another tree.
 
 Some of the other goodies include:
 
  o Added some "!" (NOT) logic to the tracing filter.
 
  o Fixed the frame pointer logic to the x86_64 mcount trampolines
 
  o Added the logic for dynamic trampolines on !CONFIG_PREEMPT systems.
    That is, the ftrace trampoline can be dynamically allocated
    and be called directly by functions that only have a single hook
    to them.
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Merge tag 'trace-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "There was a lot of clean ups and minor fixes.  One of those clean ups
  was to the trace_seq code.  It also removed the return values to the
  trace_seq_*() functions and use trace_seq_has_overflowed() to see if
  the buffer filled up or not.  This is similar to work being done to
  the seq_file code as well in another tree.

  Some of the other goodies include:

   - Added some "!" (NOT) logic to the tracing filter.

   - Fixed the frame pointer logic to the x86_64 mcount trampolines

   - Added the logic for dynamic trampolines on !CONFIG_PREEMPT systems.
     That is, the ftrace trampoline can be dynamically allocated and be
     called directly by functions that only have a single hook to them"

* tag 'trace-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (55 commits)
  tracing: Truncated output is better than nothing
  tracing: Add additional marks to signal very large time deltas
  Documentation: describe trace_buf_size parameter more accurately
  tracing: Allow NOT to filter AND and OR clauses
  tracing: Add NOT to filtering logic
  ftrace/fgraph/x86: Have prepare_ftrace_return() take ip as first parameter
  ftrace/x86: Get rid of ftrace_caller_setup
  ftrace/x86: Have save_mcount_regs macro also save stack frames if needed
  ftrace/x86: Add macro MCOUNT_REG_SIZE for amount of stack used to save mcount regs
  ftrace/x86: Simplify save_mcount_regs on getting RIP
  ftrace/x86: Have save_mcount_regs store RIP in %rdi for first parameter
  ftrace/x86: Rename MCOUNT_SAVE_FRAME and add more detailed comments
  ftrace/x86: Move MCOUNT_SAVE_FRAME out of header file
  ftrace/x86: Have static tracing also use ftrace_caller_setup
  ftrace/x86: Have static function tracing always test for function graph
  kprobes: Add IPMODIFY flag to kprobe_ftrace_ops
  ftrace, kprobes: Support IPMODIFY flag to find IP modify conflict
  kprobes/ftrace: Recover original IP if pre_handler doesn't change it
  tracing/trivial: Fix typos and make an int into a bool
  tracing: Deletion of an unnecessary check before iput()
  ...
2014-12-10 19:58:13 -08:00
Linus Torvalds 8139548136 Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "Changes in this cycle are:

   - support module unload for efivarfs (Mathias Krause)

   - another attempt at moving x86 to libstub taking advantage of the
     __pure attribute (Ard Biesheuvel)

   - add EFI runtime services section to ptdump (Mathias Krause)"

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, ptdump: Add section for EFI runtime services
  efi/x86: Move x86 back to libstub
  efivarfs: Allow unloading when build as module
2014-12-10 12:42:16 -08:00
Steven Rostedt (Red Hat) dbcf3e06ca RAS/tracing: Use trace_seq_buffer_ptr() helper instead of open coded
Use the helper function trace_seq_buffer_ptr() to get the current location
of the next buffer write of a trace_seq object, instead of open coding
it.

This facilitates the conversion of trace_seq to use seq_buf.

Tested-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Cc: Chen Gong <gong.chen@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19 15:25:37 -05:00
Ard Biesheuvel 243b6754cd efi/x86: Move x86 back to libstub
This reverts commit 84be880560, which itself reverted my original
attempt to move x86 from #include'ing .c files from across the tree
to using the EFI stub built as a static library.

The issue that affected the original approach was that splitting
the implementation into several .o files resulted in the variable
'efi_early' becoming a global with external linkage, which under
-fPIC implies that references to it must go through the GOT. However,
dealing with this additional GOT entry turned out to be troublesome
on some EFI implementations. (GCC's visibility=hidden attribute is
supposed to lift this requirement, but it turned out not to work on
the 32-bit build.)

Instead, use a pure getter function to get a reference to efi_early.
This approach results in no additional GOT entries being generated,
so there is no need for any changes in the early GOT handling.

Tested-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-11-11 22:23:11 +00:00
Mark Rutland 0bcaa9040d efi: efi-stub: notify on DTB absence
In the absence of a DTB configuration table, the EFI stub will happily
continue attempting to boot a kernel, despite the fact that this kernel
may not function without a description of the hardware. In this case, as
with a typo'd "dtb=" option (e.g. "dbt=") or many other possible
failures, the only output seen by the user will be the rather terse
output from the EFI stub:

EFI stub: Booting Linux Kernel...

To aid those attempting to debug such failures, this patch adds a notice
when no DTB is found, making the output more helpful:

EFI stub: Booting Linux Kernel...
EFI stub: Generating empty DTB

Additionally, a positive acknowledgement is added when a user-specified
DTB is in use:

EFI stub: Booting Linux Kernel...
EFI stub: Using DTB from command line

Similarly, a positive acknowledgement is added when a DTB from a
configuration table is in use:

EFI stub: Booting Linux Kernel...
EFI stub: Using DTB from configuration table

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Roy Franz <roy.franz@linaro.org>
Acked-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2014-11-05 09:03:34 +01:00
Ard Biesheuvel fc43026278 dmi: add support for SMBIOS 3.0 64-bit entry point
The DMTF SMBIOS reference spec v3.0.0 defines a new 64-bit entry point,
which enables support for SMBIOS structure tables residing at a physical
offset over 4 GB. This is especially important for upcoming arm64
platforms whose system RAM resides entirely above the 4 GB boundary.

For the UEFI case, this code attempts to detect the new SMBIOS 3.0
header magic at the offset passed in the SMBIOS3_TABLE_GUID UEFI
configuration table. If this configuration table is not provided, or
if we fail to parse the header, we fall back to using the legacy
SMBIOS_TABLE_GUID configuration table. This is in line with the spec,
that allows both configuration tables to be provided, but mandates that
they must point to the same structure table, unless the version pointed
to by the 64-bit entry point is a superset of the 32-bit one.

For the non-UEFI case, the detection logic is modified to look for the
SMBIOS 3.0 header magic before it looks for the legacy header magic.

Note that this patch is based on version 3.0.0d [draft] of the
specification, which is expected not to deviate from the final version
in ways that would affect the correctness of this implementation.

Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tony Luck <tony.luck@intel.com>
Acked-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2014-11-05 09:03:19 +01:00
Ard Biesheuvel e1ccbbc9d5 efi: dmi: add support for SMBIOS 3.0 UEFI configuration table
This adds support to the UEFI side for detecting the presence of
a SMBIOS 3.0 64-bit entry point. This allows the actual SMBIOS
structure table to reside at a physical offset over 4 GB, which
cannot be supported by the legacy SMBIOS 32-bit entry point.

Since the firmware can legally provide both entry points, store
the SMBIOS 3.0 entry point in a separate variable, and let the
DMI decoding layer decide which one will be used.

Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2014-11-05 09:03:16 +01:00
Greg Kroah-Hartman a8a93c6f99 Merge branch 'platform/remove_owner' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux into driver-core-next
Remove all .owner fields from platform drivers
2014-11-03 19:53:56 -08:00
Linus Torvalds 8c81f48e16 Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 EFI updates from Peter Anvin:
 "This patchset falls under the "maintainers that grovel" clause in the
  v3.18-rc1 announcement.  We had intended to push it late in the merge
  window since we got it into the -tip tree relatively late.

  Many of these are relatively simple things, but there are a couple of
  key bits, especially Ard's and Matt's patches"

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  rtc: Disable EFI rtc for x86
  efi: rtc-efi: Export platform:rtc-efi as module alias
  efi: Delete the in_nmi() conditional runtime locking
  efi: Provide a non-blocking SetVariable() operation
  x86/efi: Adding efi_printks on memory allocationa and pci.reads
  x86/efi: Mark initialization code as such
  x86/efi: Update comment regarding required phys mapped EFI services
  x86/efi: Unexport add_efi_memmap variable
  x86/efi: Remove unused efi_call* macros
  efi: Resolve some shadow warnings
  arm64: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
  ia64: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
  x86: efi: Format EFI memory type & attrs with efi_md_typeattr_format()
  efi: Introduce efi_md_typeattr_format()
  efi: Add macro for EFI_MEMORY_UCE memory attribute
  x86/efi: Clear EFI_RUNTIME_SERVICES if failing to enter virtual mode
  arm64/efi: Do not enter virtual mode if booting with efi=noruntime or noefi
  arm64/efi: uefi_init error handling fix
  efi: Add kernel param efi=noruntime
  lib: Add a generic cmdline parse function parse_option_str
  ...
2014-10-23 14:45:09 -07:00
Wolfram Sang e94d68450e firmware: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:20:31 +02:00
Yasuaki Ishimatsu 22880ebe76 drivers/firmware/memmap.c: don't create memmap sysfs of same firmware_map_entry
By the following commits, we prevented from allocating firmware_map_entry
of same memory range:
  f0093ede: drivers/firmware/memmap.c: don't allocate firmware_map_entry
            of same memory range
  49c8b24d: drivers/firmware/memmap.c: pass the correct argument to
            firmware_map_find_entry_bootmem()

But it's not enough. When PNP0C80 device is added by acpi_scan_init(),
memmap sysfses of same firmware_map_entry are created twice as follows:

  # cat /sys/firmware/memmap/*/start
  0x40000000000
  0x60000000000
  0x4a837000
  0x4a83a000
  0x4a8b5000
  ...
  0x40000000000
  0x60000000000
  ...

The flows of the issues are as follows:

  1. e820_reserve_resources() allocates firmware_map_entrys of all
     memory ranges defined in e820. And, these firmware_map_entrys
     are linked with map_entries list.

     map_entries -> entry 1 -> ... -> entry N

  2. When PNP0C80 device is limited by mem= boot option, acpi_scan_init()
     added the memory device. In this case, firmware_map_add_hotplug()
     allocates firmware_map_entry and creates memmap sysfs.

     map_entries -> entry 1 -> ... -> entry N -> entry N+1
                                                 |
                                                 memmap 1

  3. firmware_memmap_init() creates memmap sysfses of firmware_map_entrys
     linked with map_entries.

     map_entries -> entry 1 -> ... -> entry N -> entry N+1
                     |                 |             |
                     memmap 2          memmap N+1    memmap 1
                                                     memmap N+2

So while hot removing the PNP0C80 device, kernel panic occurs as follows:

     BUG: unable to handle kernel paging request at 00000001003e000b
      IP: sysfs_open_file+0x46/0x2b0
      PGD 203a89fe067 PUD 0
      Oops: 0000 [#1] SMP
      ...
      Call Trace:
        do_dentry_open+0x1ef/0x2a0
        finish_open+0x31/0x40
        do_last+0x57c/0x1220
        path_openat+0xc2/0x4c0
        do_filp_open+0x4b/0xb0
        do_sys_open+0xf3/0x1f0
        SyS_open+0x1e/0x20
        system_call_fastpath+0x16/0x1b

The patch adds a check of confirming whether memmap sysfs of
firmware_map_entry has been created, and does not create memmap
sysfs of same firmware_map_entry.

Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09 22:26:00 -04:00
Matt Fleming 75b128573b Merge branch 'next' into efi-next-merge
Conflicts:
	arch/x86/boot/compressed/eboot.c
2014-10-03 22:15:56 +01:00
Matt Fleming 60b4dc7720 efi: Delete the in_nmi() conditional runtime locking
commit 5dc3826d9f08 ("efi: Implement mandatory locking for UEFI Runtime
Services") implemented some conditional locking when accessing variable
runtime services that Ingo described as "pretty disgusting".

The intention with the !efi_in_nmi() checks was to avoid live-locks when
trying to write pstore crash data into an EFI variable. Such lockless
accesses are allowed according to the UEFI specification when we're in a
"non-recoverable" state, but whether or not things are implemented
correctly in actual firmware implementations remains an unanswered
question, and so it would seem sensible to avoid doing any kind of
unsynchronized variable accesses.

Furthermore, the efi_in_nmi() tests are inadequate because they don't
account for the case where we call EFI variable services from panic or
oops callbacks and aren't executing in NMI context. In other words,
live-locking is still possible.

Let's just remove the conditional locking altogether. Now we've got the
->set_variable_nonblocking() EFI variable operation we can abort if the
runtime lock is already held. Aborting is by far the safest option.

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-10-03 18:41:03 +01:00