linux/arch
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
..
alpha alpha: Remove custom dec_and_lock() implementation 2018-06-12 23:33:24 +02:00
arc mm: introduce ARCH_HAS_PTE_SPECIAL 2018-06-07 17:34:35 -07:00
arm ARM: SoC fixes for 4.18-rc 2018-07-15 09:49:21 -07:00
arm64 arm64: neon: Fix function may_use_simd() return error status 2018-07-11 17:02:02 +01:00
c6x Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-04 20:27:54 -07:00
h8300 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-04 20:27:54 -07:00
hexagon hexagon: drop the unused variable zero_page_mask 2018-06-15 07:55:25 +09:00
ia64 - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
m68k m68k: fix "bad page state" oops on ColdFire boot 2018-07-02 10:05:13 +10:00
microblaze Microblaze patches for 4.18-rc3 2018-06-27 09:49:30 -07:00
mips MIPS: Fix ioremap() RAM check 2018-07-05 14:43:21 -07:00
nds32 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-04 20:27:54 -07:00
nios2 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-04 20:27:54 -07:00
openrisc openrisc: entry: Fix delay slot exception detection 2018-07-01 16:48:24 +09:00
parisc parisc: Build kernel without -ffunction-sections 2018-06-29 17:27:20 +02:00
powerpc Kbuild fixes for v4.18 2018-06-30 13:05:30 -07:00
riscv RISC-V: Fix the rv32i kernel build 2018-07-04 14:12:53 -07:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2018-07-06 09:14:34 -07:00
sh arch/*: Kconfig: fix documentation for NMI watchdog 2018-06-15 12:48:59 -03:00
sparc arch/*: Kconfig: fix documentation for NMI watchdog 2018-06-15 12:48:59 -03:00
um Solve a series of broken links for files under Documentation: 2018-06-17 05:25:18 +09:00
unicore32 docs: Fix some broken references 2018-06-15 18:10:01 -03:00
x86 efi: Drop type and attribute checks in efi_mem_desc_lookup() 2018-07-16 00:43:12 +02:00
xtensa docs: Fix some broken references 2018-06-15 18:10:01 -03:00
.gitignore
Kconfig docs: Fix some broken references 2018-06-15 18:10:01 -03:00