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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
arch efi: Drop type and attribute checks in efi_mem_desc_lookup() 2018-07-16 00:43:12 +02:00
block for-linus-20180713 2018-07-14 12:28:00 -07:00
certs certs/blacklist: fix const confusion 2018-06-26 09:43:03 -07:00
crypto Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
Documentation Kbuild fixes for v4.18 (2nd) 2018-07-13 12:15:12 -07:00
drivers efi: Drop type and attribute checks in efi_mem_desc_lookup() 2018-07-16 00:43:12 +02:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs reiserfs: fix buffer overflow with long warning messages 2018-07-14 11:11:10 -07:00
include efi: Remove the declaration of efi_late_init() as the function is unused 2018-07-16 00:43:12 +02:00
init Kbuild fixes for v4.18 2018-06-30 13:05:30 -07:00
ipc ipc: use new return type vm_fault_t 2018-06-15 07:55:25 +09:00
kernel Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-07-13 13:36:36 -07:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-02 11:18:28 -07:00
LICENSES LICENSES: Add Linux-OpenIB license text 2018-04-27 16:41:53 -06:00
mm Merge branch 'akpm' (patches from Andrew) 2018-07-14 11:14:33 -07:00
net net/9p/client.c: put refcount of trans_mod in error case in parse_opts() 2018-07-14 11:11:09 -07:00
samples sample: vfio-mdev: avoid deadlock in mdev_access() 2018-07-11 13:22:41 -06:00
scripts checkpatch: fix duplicate invalid vsprintf pointer extension '%p<foo>' messages 2018-07-14 11:11:10 -07:00
security selinux/stable-4.18 PR 20180629 2018-06-30 11:15:12 -07:00
sound ALSA: hda/ca0132: Update a pci quirk device name 2018-07-12 09:18:31 +02:00
tools Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-07-13 13:33:09 -07:00
usr kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
virt KVM: arm64: Prevent KVM_COMPAT from being selected 2018-06-21 17:17:50 +01:00
.clang-format clang-format: add configuration file 2018-04-11 10:28:35 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap Merge branch 'asoc-4.17' into asoc-4.18 for compress dependencies 2018-04-26 12:24:28 +01:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS/CREDITS: Drop METAG ARCHITECTURE 2018-03-05 16:34:24 +00:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: add basic helper macros to scripts/Kconfig.include 2018-05-29 03:31:19 +09:00
MAINTAINERS Char/Misc fixes for 4.18-rc5 2018-07-11 10:10:50 -07:00
Makefile Linux 4.18-rc5 2018-07-15 12:49:31 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.