These fixes missed the v5.9 merge window, pick them up for early v5.10 merge.
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Nathan reports that building the new mokvar table code for 32-bit
ARM fails with errors such as

  error: implicit declaration of function 'early_memunmap'
  error: implicit declaration of function 'early_memremap'

This is caused by the lack of an explicit #include of the appropriate
header, and ARM apparently does not inherit that inclusion via another
header file. So add the #include.
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

CONFIG_EFI_VARS controls the code that exposes EFI variables via
sysfs entries, which was deprecated before support for non-Intel
architectures was added to EFI. So let's limit its availability
to Intel architectures for the time being, and hopefully remove
it entirely in the not too distant future.

While at it, let's remove the module alias so that the module is
no longer loaded automatically.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Remove some false dependencies on CONFIG_EFI_VARS, which only controls
the creation of the sysfs entries, whereas the underlying functionality
that these modules rely on is enabled unconditionally when CONFIG_EFI
is set.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

The gsmi code does not actually rely on CONFIG_EFI_VARS, since it only
uses the efivars abstraction that is included unconditionally when
CONFIG_EFI is defined. CONFIG_EFI_VARS controls the inclusion of the
code that exposes the sysfs entries, and which has been deprecated for
some time.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efivars_sysfs_init() is only used locally in the source file that
defines it, so make it static and unexport it.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

The worker thread that gets kicked off to sync the state of the
EFI variable list is only used by the EFI pstore implementation,
and is defined in its source file. So let's move its scheduling
there as well. Since our efivar_init() scan will bail on duplicate
entries, there is no need to disable the workqueue like we did
before, so we can run it unconditionally.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

The EFI pstore implementation relies on the 'efivars' abstraction,
which encapsulates the EFI variable store in a way that can be
overridden by other backing stores, like the Google SMI one.

On top of that, the EFI pstore implementation also relies on the
efivars.ko module, which is a separate layer built on top of the
'efivars' abstraction that exposes the [deprecated] sysfs entries
for each variable that exists in the backing store.

Since the efivars.ko module is deprecated, and all users appear to
have moved to the efivarfs file system instead, let's prepare for
its removal, by removing EFI pstore's dependency on it.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Fix a couple of issues in the new mokvar-table handling code, as
pointed out by Arvind and Boris:
- don't bother checking the end of the physical region against the start
  address of the mokvar table,
- ensure that we enter the loop with err = -EINVAL,
- replace size_t with unsigned long to appease pedantic type equality
  checks.
Reviewed-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Lenny Szubowicz <lszubowi@redhat.com>
Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Currently, on arm64, we abort on any failure from efi_get_random_bytes()
other than EFI_NOT_FOUND when it comes to setting the physical seed for
KASLR, but ignore such failures when obtaining the seed for virtual
KASLR or for early seeding of the kernel's entropy pool via the config
table. This is inconsistent, and may lead to unexpected boot failures.

So let's permit any failure for the physical seed, and simply report
the error code if it does not equal EFI_NOT_FOUND.

Cc: <stable@vger.kernel.org> # v5.8+
Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Without this patch efivarfs_alloc_dentry creates dentries with slashes in
their name if the respective EFI variable has slashes in its name. This in
turn causes EIO on getdents64, which prevents a complete directory listing
of /sys/firmware/efi/efivars/.

This patch replaces the invalid shlashes with exclamation marks like
kobject_set_name_vargs does for /sys/firmware/efi/vars/ to have consistently
named dentries under /sys/firmware/efi/vars/ and /sys/firmware/efi/efivars/.
Signed-off-by: Michael Schaller <misch@google.com>
Link: https://lore.kernel.org/r/20200925074502.150448-1-misch@google.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Delete deprecated parameter comments to  fix warnings reported by make
W=1.
drivers/firmware/efi/vars.c:428: warning: Excess function parameter
'atomic' description in 'efivar_init'
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/1600914018-12697-1-git-send-email-tiantao6@hisilicon.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Fix the following warnings.
drivers/firmware/efi/libstub/string.c:83:20: warning: no previous
prototype for ‘simple_strtoull’ [-Wmissing-prototypes]
drivers/firmware/efi/libstub/string.c:108:6: warning: no previous
prototype for ‘simple_strtol’ [-Wmissing-prototypes]
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/1600653203-57909-1-git-send-email-tiantao6@hisilicon.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Incorporate the definition of EFI_MEMORY_CPU_CRYPTO from the UEFI
specification v2.8, and wire it into our memory map dumping routine
as well.

To make a bit of space in the output buffer, which is provided by
the various callers, shorten the descriptive names of the memory
types.
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Updates to the UEFI 2.8 Memory Error Record allow splitting the bank field
into bank address and bank group, and using the last 3 bits of the extended
field as a chip identifier.

When needed, print correct version of bank field, bank group, and chip
identification.

Based on UEFI 2.8 Table 299. Memory Error Record.
Signed-off-by: Alex Kluver <alex.kluver@hpe.com>
Reviewed-by: Russ Anderson <russ.anderson@hpe.com>
Reviewed-by: Kyle Meyer <kyle.meyer@hpe.com>
Reviewed-by: Steve Wahl <steve.wahl@hpe.com>
Acked-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20200819143544.155096-3-alex.kluver@hpe.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Memory errors could be printed with incorrect row values since the DIMM
size has outgrown the 16 bit row field in the CPER structure. UEFI
Specification Version 2.8 has increased the size of row by allowing it to
use the first 2 bits from a previously reserved space within the structure.

When needed, add the extension bits to the row value printed.

Based on UEFI 2.8 Table 299. Memory Error Record
Signed-off-by: Alex Kluver <alex.kluver@hpe.com>
Tested-by: Russ Anderson <russ.anderson@hpe.com>
Reviewed-by: Steve Wahl <steve.wahl@hpe.com>
Reviewed-by: Kyle Meyer <kyle.meyer@hpe.com>
Acked-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20200819143544.155096-2-alex.kluver@hpe.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

At least some versions of Dell EFI firmware pass the entire
EFI_LOAD_OPTION descriptor, rather than just the OptionalData part, to
the loaded image. This was verified with firmware revision 2.15.0 on a
Dell Precision T3620 by Jacobo Pantoja.

To handle this, add a quirk to check if the options look like a valid
EFI_LOAD_OPTION descriptor, and if so, use the OptionalData part as the
command line.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reported-by: Jacobo Pantoja <jacobopantoja@gmail.com>
Link: https://lore.kernel.org/linux-efi/20200907170021.GA2284449@rani.riverdale.lan/
Link: https://lore.kernel.org/r/20200914213535.933454-2-nivedita@alum.mit.eduSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Add an efi_warn logging helper for warnings, and implement an analog of
printk_once for once-only logging.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200914213535.933454-1-nivedita@alum.mit.eduSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Because of system-specific EFI firmware limitations, EFI volatile
variables may not be capable of holding the required contents of
the Machine Owner Key (MOK) certificate store when the certificate
list grows above some size. Therefore, an EFI boot loader may pass
the MOK certs via a EFI configuration table created specifically for
this purpose to avoid this firmware limitation.

An EFI configuration table is a much more primitive mechanism
compared to EFI variables and is well suited for one-way passage
of static information from a pre-OS environment to the kernel.

This patch adds the support to load certs from the MokListRT
entry in the MOK variable configuration table, if it's present.
The pre-existing support to load certs from the MokListRT EFI
variable remains and is used if the EFI MOK configuration table
isn't present or can't be successfully used.
Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com>
Link: https://lore.kernel.org/r/20200905013107.10457-4-lszubowi@redhat.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Move the loading of certs from the UEFI MokListRT into a separate
routine to facilitate additional MokList functionality.

There is no visible functional change as a result of this patch.
Although the UEFI dbx certs are now loaded before the MokList certs,
they are loaded onto different key rings. So the order of the keys
on their respective key rings is the same.
Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Link: https://lore.kernel.org/r/20200905013107.10457-3-lszubowi@redhat.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Because of system-specific EFI firmware limitations, EFI volatile
variables may not be capable of holding the required contents of
the Machine Owner Key (MOK) certificate store when the certificate
list grows above some size. Therefore, an EFI boot loader may pass
the MOK certs via a EFI configuration table created specifically for
this purpose to avoid this firmware limitation.

An EFI configuration table is a much more primitive mechanism
compared to EFI variables and is well suited for one-way passage
of static information from a pre-OS environment to the kernel.

This patch adds initial kernel support to recognize, parse,
and validate the EFI MOK configuration table, where named
entries contain the same data that would otherwise be provided
in similarly named EFI variables.

Additionally, this patch creates a sysfs binary file for each
EFI MOK configuration table entry found. These files are read-only
to root and are provided for use by user space utilities such as
mokutil.

A subsequent patch will load MOK certs into the trusted platform
key ring using this infrastructure.
Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com>
Link: https://lore.kernel.org/r/20200905013107.10457-2-lszubowi@redhat.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Fix the warning below.
efi/libstub/vsprintf.c:135:2-3: Unneeded semicolon
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Acked-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/1599633872-36784-1-git-send-email-tiantao6@hisilicon.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Before commit

  d0f9ca9b ("ARM: decompressor: run decompressor in place if loaded via UEFI")

we were rather limited in the choice of base address for the uncompressed
kernel, as we were relying on the logic in the decompressor that blindly
rounds down the decompressor execution address to the next multiple of 128
MiB, and decompresses the kernel there. For this reason, we have a lot of
complicated memory region handling code, to ensure that this memory window
is available, even though it could be occupied by reserved regions or
other allocations that may or may not collide with the uncompressed image.

Today, we simply pass the target address for the decompressed image to the
decompressor directly, and so we can choose a suitable window just by
finding a 16 MiB aligned region, while taking TEXT_OFFSET and the region
for the swapper page tables into account.

So let's get rid of the complicated logic, and instead, use the existing
bottom up allocation routine to allocate a suitable window as low as
possible, and carve out a memory region that has the right properties.

Note that this removes any dependencies on the 'dram_base' argument to
handle_kernel_image(), and so this is removed as well. Given that this
was the only remaining use of dram_base, the code that produces it is
removed entirely as well.
Reviewed-by: Maxim Uvarov <maxim.uvarov@linaro.org>
Tested-by: Maxim Uvarov <maxim.uvarov@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Permit arm32-stub.c to access efi_low_alloc_above() in a subsequent
patch by giving it external linkage and declaring it in efistub.h.
Reviewed-by: Maxim Uvarov <maxim.uvarov@linaro.org>
Tested-by: Maxim Uvarov <maxim.uvarov@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

The way we use the base of DRAM in the EFI stub is problematic as it
is ill defined what the base of DRAM actually means. There are some
restrictions on the placement of FDT and initrd which are defined in
terms of dram_base, but given that the placement of the kernel in
memory is what defines these boundaries (as on ARM, this is where the
linear region starts), it is better to use the image address in these
cases, and disregard dram_base altogether.
Reviewed-by: Maxim Uvarov <maxim.uvarov@linaro.org>
Tested-by: Maxim Uvarov <maxim.uvarov@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Branden reports that commit

  f88814cc ("efi/efivars: Expose RT service availability via efivars abstraction")

regresses UEFI platforms that implement GetVariable but not SetVariable
when booting kernels that have EFIBC (bootloader control) enabled.

The reason is that EFIBC is a user of the efivars abstraction, which was
updated to permit users that rely only on the read capability, but not on
the write capability. EFIBC is in the latter category, so it has to check
explicitly whether efivars supports writes.

Fixes: f88814cc ("efi/efivars: Expose RT service availability via efivars abstraction")
Tested-by: Branden Sherrell <sherrellbc@gmail.com>
Link: https://lore.kernel.org/linux-efi/AE217103-C96F-4AFC-8417-83EC11962004@gmail.com/Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

arm-init is responsible for setting up efi runtime and doesn't actually
do any ARM specific stuff. RISC-V can use the same source code as it is.

Rename it to efi-init so that RISC-V can use it.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Link: https://lore.kernel.org/r/20200819222425.30721-8-atish.patra@wdc.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Define RISC-V related machine types.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Link: https://lore.kernel.org/r/20200415195422.19866-3-atish.patra@wdc.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

The old EFI runtime region mapping logic that was kept around for some
time has finally been removed entirely, along with the SGI UV1 support
code that was its last remaining user. So remove any mention of the
efi=old_map command line parameter from the docs.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Now that the old memmap code has been removed, some code that was left
behind in arch/x86/platform/efi/efi.c is only used for 32-bit builds,
which means it can live in efi_32.c as well. So move it over.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Make the command line parsing more robust, by handling the case it is
not NUL-terminated.

Use strnlen instead of strlen, and make sure that the temporary copy is
NUL-terminated before parsing.

Cc: <stable@vger.kernel.org>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200813185811.554051-4-nivedita@alum.mit.eduSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Treat a NULL cmdline the same as empty. Although this is unlikely to
happen in practice, the x86 kernel entry does check for NULL cmdline and
handles it, so do it here as well.

Cc: <stable@vger.kernel.org>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200729193300.598448-1-nivedita@alum.mit.eduSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Arguments after "--" are arguments for init, not for the kernel.

Cc: <stable@vger.kernel.org>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200725155916.1376773-1-nivedita@alum.mit.eduSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

destroy_workqueue() should be called to destroy efi_rts_wq
when efisubsys_init() init resources fails.

Cc: <stable@vger.kernel.org>
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Li Heng <liheng40@huawei.com>
Link: https://lore.kernel.org/r/1595229738-10087-1-git-send-email-liheng40@huawei.comSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

When remapping the kernel rodata section RO in the EFI pagetables, the
protection flags that were used for the text section are being reused,
but the rodata section should not be marked executable.

Cc: <stable@vger.kernel.org>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200717194526.3452089-1-nivedita@alum.mit.eduSigned-off-by: Ard Biesheuvel <ardb@kernel.org>

Pull io_uring fixes from Jens Axboe:
 "A few differerent things in here.

  Seems like syzbot got some more io_uring bits wired up, and we got a
  handful of reports and the associated fixes are in here.

  General fixes too, and a lot of them marked for stable.

  Lastly, a bit of fallout from the async buffered reads, where we now
  more easily trigger short reads. Some applications don't really like
  that, so the io_read() code now handles short reads internally, and
  got a cleanup along the way so that it's now easier to read (and
  documented). We're now passing tests that failed before"

* tag 'io_uring-5.9-2020-08-15' of git://git.kernel.dk/linux-block:
  io_uring: short circuit -EAGAIN for blocking read attempt
  io_uring: sanitize double poll handling
  io_uring: internally retry short reads
  io_uring: retain iov_iter state over io_read/io_write calls
  task_work: only grab task signal lock when needed
  io_uring: enable lookup of links holding inflight files
  io_uring: fail poll arm on queue proc failure
  io_uring: hold 'ctx' reference around task_work queue + execute
  fs: RWF_NOWAIT should imply IOCB_NOIO
  io_uring: defer file table grabbing request cleanup for locked requests
  io_uring: add missing REQ_F_COMP_LOCKED for nested requests
  io_uring: fix recursive completion locking on oveflow flush
  io_uring: use TWA_SIGNAL for task_work uncondtionally
  io_uring: account locked memory before potential error case
  io_uring: set ctx sq/cq entry count earlier
  io_uring: Fix NULL pointer dereference in loop_rw_iter()
  io_uring: add comments on how the async buffered read retry works
  io_uring: io_async_buf_func() need not test page bit

Commit 1355c31e ("asm-generic: pgalloc: provide generic pmd_alloc_one()
and pmd_free_one()") converted parisc to use generic version of
pmd_alloc_one() but it missed the fact that parisc uses order-1 pages for
PMD.

Restore the original version of pmd_alloc_one() for parisc, just use
GFP_PGTABLE_KERNEL that implies __GFP_ZERO instead of GFP_KERNEL and
memset.

Fixes: 1355c31e ("asm-generic: pgalloc: provide generic pmd_alloc_one() and pmd_free_one()")
Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Tested-by: Meelis Roos <mroos@linux.ee>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lkml.kernel.org/r/9f2b5ebd-e4a4-0fa1-6cd3-4b9f6892d1ad@linux.eeSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull block fixes from Jens Axboe:
 "A few fixes on the block side of things:

   - Discard granularity fix (Coly)

   - rnbd cleanups (Guoqing)

   - md error handling fix (Dan)

   - md sysfs fix (Junxiao)

   - Fix flush request accounting, which caused an IO slowdown for some
     configurations (Ming)

   - Properly propagate loop flag for partition scanning (Lennart)"

* tag 'block-5.9-2020-08-14' of git://git.kernel.dk/linux-block:
  block: fix double account of flush request's driver tag
  loop: unset GENHD_FL_NO_PART_SCAN on LOOP_CONFIGURE
  rnbd: no need to set bi_end_io in rnbd_bio_map_kern
  rnbd: remove rnbd_dev_submit_io
  md-cluster: Fix potential error pointer dereference in resize_bitmaps()
  block: check queue's limits.discard_granularity in __blkdev_issue_discard()
  md: get sysfs entry after redundancy attr group create

Pull RISC-V fix from Palmer Dabbelt:
 "I collected a single fix during the merge window: we managed to break
  the early trap setup on !MMU, this fixes it"

* tag 'riscv-for-linus-5.9-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: Setup exception vector for nommu platform