Commit Graph

91 Commits

Author SHA1 Message Date
Ard Biesheuvel 582a32e708 efi/arm: Revert "Defer persistent reservations until after paging_init()"
This reverts commit eff8962888, which
deferred the processing of persistent memory reservations to a point
where the memory may have already been allocated and overwritten,
defeating the purpose.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190215123333.21209-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-16 15:02:03 +01:00
Ard Biesheuvel 80424b02d4 efi: Reduce the amount of memblock reservations for persistent allocations
The current implementation of efi_mem_reserve_persistent() is rather
naive, in the sense that for each invocation, it creates a separate
linked list entry to describe the reservation. Since the linked list
entries themselves need to persist across subsequent kexec reboots,
every reservation created this way results in two memblock_reserve()
calls at the next boot.

On arm64 systems with 100s of CPUs, this may result in a excessive
number of memblock reservations, and needless fragmentation.

So instead, make use of the newly updated struct linux_efi_memreserve
layout to put multiple reservations into a single linked list entry.
This should get rid of the numerous tiny memblock reservations, and
effectively cut the total number of reservations in half on arm64
systems with many CPUs.

 [ mingo: build warning fix. ]

Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arend van Spriel <arend.vanspriel@broadcom.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Eric Snowberg <eric.snowberg@oracle.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Jon Hunter <jonathanh@nvidia.com>
Cc: Julien Thierry <julien.thierry@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: YiFei Zhu <zhuyifei1999@gmail.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20181129171230.18699-11-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-11-30 09:37:57 +01:00
Ard Biesheuvel 5f0b0ecf04 efi: Permit multiple entries in persistent memreserve data structure
In preparation of updating efi_mem_reserve_persistent() to cause less
fragmentation when dealing with many persistent reservations, update
the struct definition and the code that handles it currently so it
can describe an arbitrary number of reservations using a single linked
list entry. The actual optimization will be implemented in a subsequent
patch.

Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arend van Spriel <arend.vanspriel@broadcom.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Eric Snowberg <eric.snowberg@oracle.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Jon Hunter <jonathanh@nvidia.com>
Cc: Julien Thierry <julien.thierry@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: YiFei Zhu <zhuyifei1999@gmail.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20181129171230.18699-10-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-11-30 09:10:31 +01:00
Ard Biesheuvel 976b489120 efi: Prevent GICv3 WARN() by mapping the memreserve table before first use
Mapping the MEMRESERVE EFI configuration table from an early initcall
is too late: the GICv3 ITS code that creates persistent reservations
for the boot CPU's LPI tables is invoked from init_IRQ(), which runs
much earlier than the handling of the initcalls. This results in a
WARN() splat because the LPI tables cannot be reserved persistently,
which will result in silent memory corruption after a kexec reboot.

So instead, invoke the initialization performed by the initcall from
efi_mem_reserve_persistent() itself as well, but keep the initcall so
that the init is guaranteed to have been called before SMP boot.

Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Jan Glauber <jglauber@cavium.com>
Tested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 63eb322d89 ("efi: Permit calling efi_mem_reserve_persistent() ...")
Link: http://lkml.kernel.org/r/20181123215132.7951-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-11-27 13:50:20 +01:00
Ard Biesheuvel 63eb322d89 efi: Permit calling efi_mem_reserve_persistent() from atomic context
Currently, efi_mem_reserve_persistent() may not be called from atomic
context, since both the kmalloc() call and the memremap() call may
sleep.

The kmalloc() call is easy enough to fix, but the memremap() call
needs to be moved into an init hook since we cannot control the
memory allocation behavior of memremap() at the call site.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20181114175544.12860-6-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-11-15 10:04:47 +01:00
Ard Biesheuvel eff8962888 efi/arm: Defer persistent reservations until after paging_init()
The new memory EFI reservation feature we introduced to allow memory
reservations to persist across kexec may trigger an unbounded number
of calls to memblock_reserve(). The memblock subsystem can deal with
this fine, but not before memblock resizing is enabled, which we can
only do after paging_init(), when the memory we reallocate the array
into is actually mapped.

So break out the memreserve table processing into a separate routine
and call it after paging_init() on arm64. On ARM, because of limited
reviewing bandwidth of the maintainer, we cannot currently fix this,
so instead, disable the EFI persistent memreserve entirely on ARM so
we can fix it later.

Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20181114175544.12860-5-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-11-15 10:04:46 +01:00
Ard Biesheuvel a23d3bb05c efi: add API to reserve memory persistently across kexec reboot
Add kernel plumbing to reserve memory regions persistently on a EFI
system by adding entries to the MEMRESERVE linked list.

Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2018-09-26 12:03:57 +02:00
Ard Biesheuvel 71e0940d52 efi: honour memory reservations passed via a linux specific config table
In order to allow the OS to reserve memory persistently across a
kexec, introduce a Linux-specific UEFI configuration table that
points to the head of a linked list in memory, allowing each kernel
to add list items describing memory regions that the next kernel
should treat as reserved.

This is useful, e.g., for GICv3 based ARM systems that cannot disable
DMA access to the LPI tables, forcing them to reuse the same memory
region again after a kexec reboot.

Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2018-09-26 12:03:49 +02:00
Linus Torvalds 203b4fc903 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Thomas Gleixner:

 - Make lazy TLB mode even lazier to avoid pointless switch_mm()
   operations, which reduces CPU load by 1-2% for memcache workloads

 - Small cleanups and improvements all over the place

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Remove redundant check for kmem_cache_create()
  arm/asm/tlb.h: Fix build error implicit func declaration
  x86/mm/tlb: Make clear_asid_other() static
  x86/mm/tlb: Skip atomic operations for 'init_mm' in switch_mm_irqs_off()
  x86/mm/tlb: Always use lazy TLB mode
  x86/mm/tlb: Only send page table free TLB flush to lazy TLB CPUs
  x86/mm/tlb: Make lazy TLB mode lazier
  x86/mm/tlb: Restructure switch_mm_irqs_off()
  x86/mm/tlb: Leave lazy TLB mode at page table free time
  mm: Allocate the mm_cpumask (mm->cpu_bitmap[]) dynamically based on nr_cpu_ids
  x86/mm: Add TLB purge to free pmd/pte page interfaces
  ioremap: Update pgtable free interfaces with addr
  x86/mm: Disable ioremap free page handling on x86-PAE
2018-08-13 16:29:35 -07:00
Rik van Riel c1a2f7f0c0 mm: Allocate the mm_cpumask (mm->cpu_bitmap[]) dynamically based on nr_cpu_ids
The mm_struct always contains a cpumask bitmap, regardless of
CONFIG_CPUMASK_OFFSTACK. That means the first step can be to
simplify things, and simply have one bitmask at the end of the
mm_struct for the mm_cpumask.

This does necessitate moving everything else in mm_struct into
an anonymous sub-structure, which can be randomized when struct
randomization is enabled.

The second step is to determine the correct size for the
mm_struct slab object from the size of the mm_struct
(excluding the CPU bitmap) and the size the cpumask.

For init_mm we can simply allocate the maximum size this
kernel is compiled for, since we only have one init_mm
in the system, anyway.

Pointer magic by Mike Galbraith, to evade -Wstringop-overflow
getting confused by the dynamically sized array.

Tested-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Rik van Riel <riel@surriel.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-team@fb.com
Cc: luto@kernel.org
Link: http://lkml.kernel.org/r/20180716190337.26133-2-riel@surriel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-17 09:35:30 +02:00
Ard Biesheuvel 7e1550b8f2 efi: Drop type and attribute checks in efi_mem_desc_lookup()
The current implementation of efi_mem_desc_lookup() includes the
following check on the memory descriptor it returns:

    if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
        md->type != EFI_BOOT_SERVICES_DATA &&
        md->type != EFI_RUNTIME_SERVICES_DATA) {
            continue;
    }

This means that only EfiBootServicesData or EfiRuntimeServicesData
regions are considered, or any other region type provided that it
has the EFI_MEMORY_RUNTIME attribute set.

Given what the name of the function implies, and the fact that any
physical address can be described in the UEFI memory map only a single
time, it does not make sense to impose this condition in the body of the
loop, but instead, should be imposed by the caller depending on the value
that is returned to it.

Two such callers exist at the moment:

- The BGRT code when running on x86, via efi_mem_reserve() and
  efi_arch_mem_reserve(). In this case, the region is already known to
  be EfiBootServicesData, and so the check is redundant.

- The ESRT handling code which introduced this function, which calls it
  both directly from efi_esrt_init() and again via efi_mem_reserve() and
  efi_arch_mem_reserve() [on x86].

So let's move this check into the callers instead. This preserves the
current behavior both for BGRT and ESRT handling, and allows the lookup
routine to be reused by other [upcoming] users that don't have this
limitation.

In the ESRT case, keep the entire condition, so that platforms that
deviate from the UEFI spec and use something other than
EfiBootServicesData for the ESRT table will keep working as before.

For x86's efi_arch_mem_reserve() implementation, limit the type to
EfiBootServicesData, since it is the only type the reservation code
expects to operate on in the first place.

While we're at it, drop the __init annotation so that drivers can use it
as well.

Tested-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180711094040.12506-8-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-16 00:43:12 +02:00
Sai Praneeth 3eb420e70d efi: Use a work queue to invoke EFI Runtime Services
Presently, when a user process requests the kernel to execute any
UEFI runtime service, the kernel temporarily switches to a separate
set of page tables that describe the virtual mapping of the UEFI
runtime services regions in memory. Since UEFI runtime services are
typically invoked with interrupts enabled, any code that may be called
during this time, will have an incorrect view of the process's address
space. Although it is unusual for code running in interrupt context to
make assumptions about the process context it runs in, there are cases
(such as the perf subsystem taking samples) where this causes problems.

So let's set up a work queue for calling UEFI runtime services, so that
the actual calls are made when the work queue items are dispatched by a
work queue worker running in a separate kernel thread. Such threads are
not expected to have userland mappings in the first place, and so the
additional mappings created for the UEFI runtime services can never
clash with any.

The ResetSystem() runtime service is not covered by the work queue
handling, since it is not expected to return, and may be called at a
time when the kernel is torn down to the point where we cannot expect
work queues to still be operational.

The non-blocking variants of SetVariable() and QueryVariableInfo()
are also excluded: these are intended to be used from atomic context,
which obviously rules out waiting for a completion to be signalled by
another thread. Note that these variants are currently only used for
UEFI runtime services calls that occur very early in the boot, and
for ones that occur in critical conditions, e.g., to flush kernel logs
to UEFI variables via efi-pstore.

Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
[ardb: exclude ResetSystem() from the workqueue treatment
       merge from 2 separate patches and rewrite commit log]
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180711094040.12506-4-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-16 00:43:12 +02:00
Sai Praneeth 7e904a91bf efi: Use efi_mm in x86 as well as ARM
Presently, only ARM uses mm_struct to manage EFI page tables and EFI
runtime region mappings. As this is the preferred approach, let's make
this data structure common across architectures. Specially, for x86,
using this data structure improves code maintainability and readability.

Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
[ardb: don't #include the world to get a declaration of struct mm_struct]
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Lee, Chun-Yi <jlee@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180312084500.10764-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 10:05:01 +01:00
Ard Biesheuvel 5b4e4c3aa2 efi: Reorder pr_notice() with add_device_randomness() call
Currently, when we receive a random seed from the EFI stub, we call
add_device_randomness() to incorporate it into the entropy pool, and
issue a pr_notice() saying we are about to do that, e.g.,

  [    0.000000] efi:  RNG=0x87ff92cf18
  [    0.000000] random: fast init done
  [    0.000000] efi: seeding entropy pool

Let's reorder those calls to make the output look less confusing:

  [    0.000000] efi: seeding entropy pool
  [    0.000000] efi:  RNG=0x87ff92cf18
  [    0.000000] random: fast init done

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180308080020.22828-11-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-09 08:58:23 +01:00
Linus Torvalds ae0cb7be35 Merge branch 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull tpm updates from James Morris:

 - reduce polling delays in tpm_tis

 - support retrieving TPM 2.0 Event Log through EFI before
   ExitBootServices

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

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

 - CLKRUN fixes:

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

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

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

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

Signed-off-by: Thiebaud Weksteen <tweek@google.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
2018-01-08 12:58:35 +02:00
Vasyl Gomonovych 50342b2e49 efi: Use PTR_ERR_OR_ZERO()
Fix ptr_ret.cocci warnings:

  drivers/firmware/efi/efi.c:610:8-14: WARNING: PTR_ERR_OR_ZERO can be used

Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR

Generated by: scripts/coccinelle/api/ptr_ret.cocci

Signed-off-by: Vasyl Gomonovych <gomonovych@gmail.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arvind Yadav <arvind.yadav.cs@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tyler Baicar <tbaicar@codeaurora.org>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180102181042.19074-4-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-03 14:03:48 +01:00
Dave Young 0b02e448a2 efi: Add comment to avoid future expanding of sysfs systab
/sys/firmware/efi/systab shows several different values, it breaks sysfs
one file one value design.  But since there are already userspace tools
depend on it eg. kexec-tools so add code comment to alert future expanding
of this file.

Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20171206095010.24170-4-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-06 19:32:23 +01:00
Greg Kroah-Hartman af97a77bc0 efi: Move some sysfs files to be read-only by root
Thanks to the scripts/leaking_addresses.pl script, it was found that
some EFI values should not be readable by non-root users.

So make them root-only, and to do that, add a __ATTR_RO_MODE() macro to
make this easier, and use it in other places at the same time.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Cc: stable <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20171206095010.24170-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-06 19:31:39 +01:00
Jan Beulich 23f0571c9f efi: Move efi_mem_type() to common code
This follows efi_mem_attributes(), as it's similarly generic. Drop
__weak from that one though (and don't introduce it for efi_mem_type()
in the first place) to make clear that other overrides to these
functions are really not intended.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825155019.6740-5-ard.biesheuvel@linaro.org
[ Resolved conflict with: f99afd08a45f: (efi: Update efi_mem_type() to return an error rather than 0) ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-26 09:20:33 +02:00
Ard Biesheuvel c2ceb5fd4e efi/random: Increase size of firmware supplied randomness
The crng code requires at least 64 bytes (2 * CHACHA20_BLOCK_SIZE)
to complete the fast boot-time init, so provide that many bytes
when invoking UEFI protocols to seed the entropy pool. Also, add
a notice so we can tell from the boot log when the seeding actually
took place.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825155019.6740-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-26 09:20:33 +02:00
Ingo Molnar 3cb9bc8502 Merge branch 'x86/mm' into efi/core, to pick up dependencies
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-26 09:20:01 +02:00
Arvind Yadav 3ad6bd7c0a firmware/efi: Constify attribute_group structures
attribute_group are not supposed to change at runtime. All functions
working with attribute_group provided by <linux/sysfs.h> work with
const attribute_group. So mark the non-const structs as const.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170818194947.19347-14-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-21 09:43:51 +02:00
Tom Lendacky a19d66c56a efi: Add an EFI table address match function
Add a function that will determine if a supplied physical address matches
the address of an EFI table.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Toshimitsu Kani <toshi.kani@hpe.com>
Cc: kasan-dev@googlegroups.com
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/e1e06441d80f44776df391e0e4cb485b345b7518.1500319216.git.thomas.lendacky@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:38:01 +02:00
Daniel Kiper 457ea3f7e9 efi: Process the MEMATTR table only if EFI_MEMMAP is enabled
Otherwise e.g. Xen dom0 on x86_64 EFI platforms crashes.

In theory we can check EFI_PARAVIRT too, however,
EFI_MEMMAP looks more targeted and covers more cases.

Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andrew.cooper3@citrix.com
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: linux-efi@vger.kernel.org
Cc: matt@codeblueprint.co.uk
Cc: stable@vger.kernel.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1498128697-12943-2-git-send-email-daniel.kiper@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-23 11:11:02 +02:00
Daniel Drake 822f5845f7 efi/esrt: Cleanup bad memory map log messages
The Intel Compute Stick STCK1A8LFC and Weibu F3C platforms both
log 2 error messages during boot:

   efi: requested map not found.
   esrt: ESRT header is not in the memory map.

Searching the web, this seems to affect many other platforms too.
Since these messages are logged as errors, they appear on-screen during
the boot process even when using the "quiet" boot parameter used by
distros.

Demote the ESRT error to a warning so that it does not appear on-screen,
and delete the error logging from efi_mem_desc_lookup; both callsites
of that function log more specific messages upon failure.

Out of curiosity I looked closer at the Weibu F3C. There is no entry in
the UEFI-provided memory map which corresponds to the ESRT pointer, but
hacking the code to map it anyway, the ESRT does appear to be valid with
2 entries.

Signed-off-by: Daniel Drake <drake@endlessm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Acked-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2017-03-17 18:53:12 +00:00
Sai Praneeth 3a6b6c6fb2 efi: Make EFI_MEMORY_ATTRIBUTES_TABLE initialization common across all architectures
Since EFI_PROPERTIES_TABLE and EFI_MEMORY_ATTRIBUTES_TABLE deal with
updating memory region attributes, it makes sense to call
EFI_MEMORY_ATTRIBUTES_TABLE initialization function from the same place
as EFI_PROPERTIES_TABLE. This also moves the EFI_MEMORY_ATTRIBUTES_TABLE
initialization code to a more generic efi initialization path rather
than ARM specific efi initialization. This is important because
EFI_MEMORY_ATTRIBUTES_TABLE will be supported by x86 as well.

Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Lee, Chun-Yi <jlee@suse.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1485868902-20401-4-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-01 08:45:43 +01:00
Ard Biesheuvel 636259880a efi: Add support for seeding the RNG from a UEFI config table
Specify a Linux specific UEFI configuration table that carries some
random bits, and use the contents during early boot to seed the kernel's
random number generator. This allows much strong random numbers to be
generated early on.

The entropy is fed to the kernel using add_device_randomness(), which is
documented as being appropriate for being called very early.

Since UEFI configuration tables may also be consumed by kexec'd kernels,
register a reboot notifier that updates the seed in the table.

Note that the config table could be generated by the EFI stub or by any
other UEFI driver or application (e.g., GRUB), but the random seed table
GUID and the associated functionality should be considered an internal
kernel interface (unless it is promoted to ABI later on)

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20161112213237.8804-4-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-13 08:23:14 +01:00
Dan Carpenter a75dcb5848 efi/efivar_ssdt_load: Don't return success on allocation failure
We should return -ENOMEM here, instead of success.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 475fb4e8b2 ("efi / ACPI: load SSTDs from EFI variables")
Link: http://lkml.kernel.org/r/20161018143318.15673-9-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-18 17:11:20 +02:00
Ingo Molnar 5465fe0fc3 * 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
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Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into efi/core

Pull EFI updates from Matt Fleming:

"* 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"

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-13 20:21:55 +02:00
Ard Biesheuvel dce48e351c efi: Replace runtime services spinlock with semaphore
The purpose of the efi_runtime_lock is to prevent concurrent calls into
the firmware. There is no need to use spinlocks here, as long as we ensure
that runtime service invocations from an atomic context (i.e., EFI pstore)
cannot block.

So use a semaphore instead, and use down_trylock() in the nonblocking case.
We don't use a mutex here because the mutex_trylock() function must not
be called from interrupt context, whereas the down_trylock() can.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Sylvain Chouleur <sylvain.chouleur@gmail.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:08:43 +01:00
Matt Fleming 816e76129e efi: Allow drivers to reserve boot services forever
Today, it is not possible for drivers to reserve EFI boot services for
access after efi_free_boot_services() has been called on x86. For
ARM/arm64 it can be done simply by calling memblock_reserve().

Having this ability for all three architectures is desirable for a
couple of reasons,

  1) It saves drivers copying data out of those regions
  2) kexec reboot can now make use of things like ESRT

Instead of using the standard memblock_reserve() which is insufficient
to reserve the region on x86 (see efi_reserve_boot_services()), a new
API is introduced in this patch; efi_mem_reserve().

efi.memmap now always represents which EFI memory regions are
available. On x86 the EFI boot services regions that have not been
reserved via efi_mem_reserve() will be removed from efi.memmap during
efi_free_boot_services().

This has implications for kexec, since it is not possible for a newly
kexec'd kernel to access the same boot services regions that the
initial boot kernel had access to unless they are reserved by every
kexec kernel in the chain.

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: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Peter Jones <pjones@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:08:34 +01:00
Matt Fleming 60863c0d1a efi: Split out EFI memory map functions into new file
Also move the functions from the EFI fake mem driver since future
patches will require access to the memmap insertion code even if
CONFIG_EFI_FAKE_MEM isn't enabled.

This will be useful when we need to build custom EFI memory maps to
allow drivers to mark regions as reserved.

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: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Peter Jones <pjones@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:07:46 +01:00
Matt Fleming dca0f971ea efi: Add efi_memmap_init_late() for permanent EFI memmap
Drivers need a way to access the EFI memory map at runtime. ARM and
arm64 currently provide this by remapping the EFI memory map into the
vmalloc space before setting up the EFI virtual mappings.

x86 does not provide this functionality which has resulted in the code
in efi_mem_desc_lookup() where it will manually map individual EFI
memmap entries if the memmap has already been torn down on x86,

  /*
   * If a driver calls this after efi_free_boot_services,
   * ->map will be NULL, and the target may also not be mapped.
   * So just always get our own virtual map on the CPU.
   *
   */
  md = early_memremap(p, sizeof (*md));

There isn't a good reason for not providing a permanent EFI memory map
for runtime queries, especially since the EFI regions are not mapped
into the standard kernel page tables.

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: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Peter Jones <pjones@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:07:43 +01:00
Matt Fleming 9479c7cebf efi: Refactor efi_memmap_init_early() into arch-neutral code
Every EFI architecture apart from ia64 needs to setup the EFI memory
map at efi.memmap, and the code for doing that is essentially the same
across all implementations. Therefore, it makes sense to factor this
out into the common code under drivers/firmware/efi/.

The only slight variation is the data structure out of which we pull
the initial memory map information, such as physical address, memory
descriptor size and version, etc. We can address this by passing a
generic data structure (struct efi_memory_map_data) as the argument to
efi_memmap_init_early() which contains the minimum info required for
initialising the memory map.

In the process, this patch also fixes a few undesirable implementation
differences:

 - ARM and arm64 were failing to clear the EFI_MEMMAP bit when
   unmapping the early EFI memory map. EFI_MEMMAP indicates whether
   the EFI memory map is mapped (not the regions contained within) and
   can be traversed.  It's more correct to set the bit as soon as we
   memremap() the passed in EFI memmap.

 - Rename efi_unmmap_memmap() to efi_memmap_unmap() to adhere to the
   regular naming scheme.

This patch also uses a read-write mapping for the memory map instead
of the read-only mapping currently used on ARM and arm64. x86 needs
the ability to update the memory map in-place when assigning virtual
addresses to regions (efi_map_region()) and tagging regions when
reserving boot services (efi_reserve_boot_services()).

There's no way for the generic fake_mem code to know which mapping to
use without introducing some arch-specific constant/hook, so just use
read-write since read-only is of dubious value for the EFI memory map.

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: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Peter Jones <pjones@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:06:38 +01:00
Andrzej Hajda 4af9ed578a efi: Fix handling error value in fdt_find_uefi_params
of_get_flat_dt_subnode_by_name can return negative value in case of error.
Assigning the result to unsigned variable and checking if the variable
is lesser than zero is incorrect and always false.
The patch fixes it by using signed variable to check the result.

The problem has been detected using semantic patch
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Shawn Lin <shawn.lin@rock-chips.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-05 11:26:42 +01:00
Linus Torvalds 08fd8c1768 xen: features and fixes for 4.8-rc0
- ACPI support for guests on ARM platforms.
 - Generic steal time support for arm and x86.
 - Support cases where kernel cpu is not Xen VCPU number (e.g., if
   in-guest kexec is used).
 - Use the system workqueue instead of a custom workqueue in various
   places.
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Merge tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from David Vrabel:
 "Features and fixes for 4.8-rc0:

   - ACPI support for guests on ARM platforms.
   - Generic steal time support for arm and x86.
   - Support cases where kernel cpu is not Xen VCPU number (e.g., if
     in-guest kexec is used).
   - Use the system workqueue instead of a custom workqueue in various
     places"

* tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (47 commits)
  xen: add static initialization of steal_clock op to xen_time_ops
  xen/pvhvm: run xen_vcpu_setup() for the boot CPU
  xen/evtchn: use xen_vcpu_id mapping
  xen/events: fifo: use xen_vcpu_id mapping
  xen/events: use xen_vcpu_id mapping in events_base
  x86/xen: use xen_vcpu_id mapping when pointing vcpu_info to shared_info
  x86/xen: use xen_vcpu_id mapping for HYPERVISOR_vcpu_op
  xen: introduce xen_vcpu_id mapping
  x86/acpi: store ACPI ids from MADT for future usage
  x86/xen: update cpuid.h from Xen-4.7
  xen/evtchn: add IOCTL_EVTCHN_RESTRICT
  xen-blkback: really don't leak mode property
  xen-blkback: constify instance of "struct attribute_group"
  xen-blkfront: prefer xenbus_scanf() over xenbus_gather()
  xen-blkback: prefer xenbus_scanf() over xenbus_gather()
  xen: support runqueue steal time on xen
  arm/xen: add support for vm_assist hypercall
  xen: update xen headers
  xen-pciback: drop superfluous variables
  xen-pciback: short-circuit read path used for merging write values
  ...
2016-07-27 11:35:37 -07:00
Octavian Purdila 475fb4e8b2 efi / ACPI: load SSTDs from EFI variables
This patch allows SSDTs to be loaded from EFI variables. It works by
specifying the EFI variable name containing the SSDT to be loaded. All
variables with the same name (regardless of the vendor GUID) will be
loaded.

Note that we can't use acpi_install_table and we must rely on the
dynamic ACPI table loading and bus re-scanning mechanisms. That is
because I2C/SPI controllers are initialized earlier then the EFI
subsystems and all I2C/SPI ACPI devices are enumerated when the
I2C/SPI controllers are initialized.

Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-08 21:52:35 +02:00
Shannon Zhao 0cac5c3018 Xen: EFI: Parse DT parameters for Xen specific UEFI
The EFI DT parameters for bare metal are located under /chosen node,
while for Xen Dom0 they are located under /hyperviosr/uefi node. These
parameters under /chosen and /hyperviosr/uefi are not expected to appear
at the same time.

Parse these EFI parameters and initialize EFI like the way for bare
metal except the runtime services because the runtime services for Xen
Dom0 are available through hypercalls and they are always enabled. So it
sets the EFI_RUNTIME_SERVICES flag if it finds /hyperviosr/uefi node and
bails out in arm_enable_runtime_services() when EFI_RUNTIME_SERVICES
flag is set already.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-07-06 10:34:47 +01:00
Matt Fleming 806b0351c9 efi: Move efi_status_to_err() to drivers/firmware/efi/
Move efi_status_to_err() to the architecture independent code as it's
generally useful in all bits of EFI code where there is a need to
convert an efi_status_t to a kernel error value.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Kweh Hock Leong <hock.leong.kweh@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: joeyli <jlee@suse.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-27-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28 11:34:03 +02:00
Ard Biesheuvel 801820bee9 efi/arm/libstub: Make screen_info accessible to the UEFI stub
In order to hand over the framebuffer described by the GOP protocol and
discovered by the UEFI stub, make struct screen_info accessible by the
stub. This involves allocating a loader data buffer and passing it to the
kernel proper via a UEFI Configuration Table, since the UEFI stub executes
in the context of the decompressor, and cannot access the kernel's copy of
struct screen_info directly.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-22-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28 11:33:59 +02:00
Ard Biesheuvel a604af075a efi: Add support for the EFI_MEMORY_ATTRIBUTES_TABLE config table
This declares the GUID and struct typedef for the new memory attributes
table which contains the permissions that can be used to apply stricter
permissions to UEFI Runtime Services memory regions.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-13-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28 11:33:54 +02:00
Matt Fleming 884f4f66ff efi: Remove global 'memmap' EFI memory map
Abolish the poorly named EFI memory map, 'memmap'. It is shadowed by a
bunch of local definitions in various files and having two ways to
access the EFI memory map ('efi.memmap' vs. 'memmap') is rather
confusing.

Furthermore, IA64 doesn't even provide this global object, which has
caused issues when trying to write generic EFI memmap code.

Replace all occurrences with efi.memmap, and convert the remaining
iterator code to use for_each_efi_mem_desc().

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Luck, Tony <tony.luck@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-8-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28 11:33:51 +02:00
Matt Fleming 78ce248faa efi: Iterate over efi.memmap in for_each_efi_memory_desc()
Most of the users of for_each_efi_memory_desc() are equally happy
iterating over the EFI memory map in efi.memmap instead of 'memmap',
since the former is usually a pointer to the latter.

For those users that want to specify an EFI memory map other than
efi.memmap, that can be done using for_each_efi_memory_desc_in_map().
One such example is in the libstub code where the firmware is queried
directly for the memory map, it gets iterated over, and then freed.

This change goes part of the way toward deleting the global 'memmap'
variable, which is not universally available on all architectures
(notably IA64) and is rather poorly named.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-7-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28 11:33:50 +02:00
Robert Elliott 35575e0e8b efi: Add Persistent Memory type name
Add the "Persistent Memory" string for type 14 introduced in
UEFI 2.5.  This is used when printing the UEFI memory map.

old:
  efi: mem61: [type=14            |   |  |  |  |  |  | |WB|WT|WC|UC] range=[0x0000000880000000-0x0000000c7fffffff) (16384MB)

new:
  efi: mem61: [Persistent Memory  |   |  |  |  |  |  | |WB|WT|WC|UC] range=[0x0000000880000000-0x0000000c7fffffff) (16384MB)

Signed-off-by: Robert Elliott <elliott@hpe.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1454364428-494-14-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 11:41:20 +01:00
Robert Elliott c016ca08f8 efi: Add NV memory attribute
Add the NV memory attribute introduced in UEFI 2.5 and add a
column for it in the types and attributes string used when
printing the UEFI memory map.

old:
  efi: mem61: [type=14            |   |  |  |  |  |  | |WB|WT|WC|UC] range=[0x0000000880000000-0x0000000c7fffffff) (16384MB)

new:
  efi: mem61: [type=14            |   |  |NV|  |  |  |  | |WB|WT|WC|UC] range=[0x0000000880000000-0x0000000c7fffffff) (16384MB)

Signed-off-by: Robert Elliott <elliott@hpe.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1454364428-494-13-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 11:41:20 +01:00
Ard Biesheuvel 9c6672ac9c efi: Expose non-blocking set_variable() wrapper to efivars
Commit 6d80dba1c9 ("efi: Provide a non-blocking SetVariable()
operation") implemented a non-blocking alternative for the UEFI
SetVariable() invocation performed by efivars, since it may
occur in atomic context. However, this version of the function
was never exposed via the efivars struct, so the non-blocking
versions was not actually callable. Fix that.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 6d80dba1c9 ("efi: Provide a non-blocking SetVariable() operation")
Link: http://lkml.kernel.org/r/1454364428-494-2-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 11:31:01 +01:00
Ingo Molnar 03e075b38e Merge branch 'linus' into efi/core, to refresh the branch and to pick up recent fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 11:30:36 +01:00
Ard Biesheuvel 0f7f2f0c0f efi: include asm/early_ioremap.h not asm/efi.h to get early_memremap
The code in efi.c uses early_memremap(), but relies on a transitive
include rather than including asm/early_ioremap.h directly, since
this header did not exist on ia64.

Commit f7d9248942 ("arm64/efi: refactor EFI init and runtime code
for reuse by 32-bit ARM") attempted to work around this by including
asm/efi.h, which transitively includes asm/early_ioremap.h on most
architectures. However, since asm/efi.h does not exist on ia64 either,
this is not much of an improvement.

Now that we have created an asm/early_ioremap.h for ia64, we can just
include it directly.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2016-01-13 10:35:14 -08:00
Sai Praneeth 50a0cb5652 x86/efi-bgrt: Fix kernel panic when mapping BGRT data
Starting with this commit 35eb8b81edd4 ("x86/efi: Build our own page
table structures") efi regions have a separate page directory called
"efi_pgd". In order to access any efi region we have to first shift %cr3
to this page table. In the bgrt code we are trying to copy bgrt_header
and image, but these regions fall under "EFI_BOOT_SERVICES_DATA"
and to access these regions we have to shift %cr3 to efi_pgd and not
doing so will cause page fault as shown below.

[    0.251599] Last level dTLB entries: 4KB 64, 2MB 0, 4MB 0, 1GB 4
[    0.259126] Freeing SMP alternatives memory: 32K (ffffffff8230e000 - ffffffff82316000)
[    0.271803] BUG: unable to handle kernel paging request at fffffffefce35002
[    0.279740] IP: [<ffffffff821bca49>] efi_bgrt_init+0x144/0x1fd
[    0.286383] PGD 300f067 PUD 0
[    0.289879] Oops: 0000 [#1] SMP
[    0.293566] Modules linked in:
[    0.297039] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.0-rc1-eywa-eywa-built-in-47041+ #2
[    0.306619] Hardware name: Intel Corporation Skylake Client platform/Skylake Y LPDDR3 RVP3, BIOS SKLSE2R1.R00.B104.B01.1511110114 11/11/2015
[    0.320925] task: ffffffff820134c0 ti: ffffffff82000000 task.ti: ffffffff82000000
[    0.329420] RIP: 0010:[<ffffffff821bca49>]  [<ffffffff821bca49>] efi_bgrt_init+0x144/0x1fd
[    0.338821] RSP: 0000:ffffffff82003f18  EFLAGS: 00010246
[    0.344852] RAX: fffffffefce35000 RBX: fffffffefce35000 RCX: fffffffefce2b000
[    0.352952] RDX: 000000008a82b000 RSI: ffffffff8235bb80 RDI: 000000008a835000
[    0.361050] RBP: ffffffff82003f30 R08: 000000008a865000 R09: ffffffffff202850
[    0.369149] R10: ffffffff811ad62f R11: 0000000000000000 R12: 0000000000000000
[    0.377248] R13: ffff88016dbaea40 R14: ffffffff822622c0 R15: ffffffff82003fb0
[    0.385348] FS:  0000000000000000(0000) GS:ffff88016d800000(0000) knlGS:0000000000000000
[    0.394533] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.401054] CR2: fffffffefce35002 CR3: 000000000300c000 CR4: 00000000003406f0
[    0.409153] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    0.417252] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[    0.425350] Stack:
[    0.427638]  ffffffffffffffff ffffffff82256900 ffff88016dbaea40 ffffffff82003f40
[    0.436086]  ffffffff821bbce0 ffffffff82003f88 ffffffff8219c0c2 0000000000000000
[    0.444533]  ffffffff8219ba4a ffffffff822622c0 0000000000083000 00000000ffffffff
[    0.452978] Call Trace:
[    0.455763]  [<ffffffff821bbce0>] efi_late_init+0x9/0xb
[    0.461697]  [<ffffffff8219c0c2>] start_kernel+0x463/0x47f
[    0.467928]  [<ffffffff8219ba4a>] ? set_init_arg+0x55/0x55
[    0.474159]  [<ffffffff8219b120>] ? early_idt_handler_array+0x120/0x120
[    0.481669]  [<ffffffff8219b5ee>] x86_64_start_reservations+0x2a/0x2c
[    0.488982]  [<ffffffff8219b72d>] x86_64_start_kernel+0x13d/0x14c
[    0.495897] Code: 00 41 b4 01 48 8b 78 28 e8 09 36 01 00 48 85 c0 48 89 c3 75 13 48 c7 c7 f8 ac d3 81 31 c0 e8 d7 3b fb fe e9 b5 00 00 00 45 84 e4 <44> 8b 6b 02 74 0d be 06 00 00 00 48 89 df e8 ae 34 0$
[    0.518151] RIP  [<ffffffff821bca49>] efi_bgrt_init+0x144/0x1fd
[    0.524888]  RSP <ffffffff82003f18>
[    0.528851] CR2: fffffffefce35002
[    0.532615] ---[ end trace 7b06521e6ebf2aea ]---
[    0.537852] Kernel panic - not syncing: Attempted to kill the idle task!

As said above one way to fix this bug is to shift %cr3 to efi_pgd but we
are not doing that way because it leaks inner details of how we switch
to EFI page tables into a new call site and it also adds duplicate code.
Instead, we remove the call to efi_lookup_mapped_addr() and always
perform early_mem*() instead of early_io*() because we want to remap RAM
regions and not I/O regions. We also delete efi_lookup_mapped_addr()
because we are no longer using it.

Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Reported-by: Wendy Wang <wendy.wang@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2015-12-14 15:24:24 +00:00