linux-toradex.git/arch/arm64/kernel/setup.c, branch v4.12

arm64: Print DT machine model in setup_machine_fdt()

2017-04-28T16:09:41+00:00

On arm32, the machine model specified in the device tree is printed
during boot-up, courtesy of of_flat_dt_match_machine().

On arm64, of_flat_dt_match_machine() is not called, and the machine
model information is not available from the kernel log.

Print the machine model to make it easier to derive the machine model
from an arbitrary kernel boot log.

Acked-by: Will Deacon 
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Catalin Marinas

arm64: kdump: reserve memory for crash dump kernel

2017-04-05T17:26:57+00:00

"crashkernel=" kernel parameter specifies the size (and optionally
the start address) of the system ram to be used by crash dump kernel.
reserve_crashkernel() will allocate and reserve that memory at boot time
of primary kernel.

The memory range will be exposed to userspace as a resource named
"Crash kernel" in /proc/iomem.

Signed-off-by: AKASHI Takahiro 
Signed-off-by: Mark Salter 
Signed-off-by: Pratyush Anand 
Reviewed-by: James Morse 
Acked-by: Catalin Marinas 
Reviewed-by: Ard Biesheuvel 
Signed-off-by: Catalin Marinas

sched/headers: Prepare to move 'init_task' and 'init_thread_union' from to

2017-03-02T07:42:38+00:00

Update all usage sites first.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

arm64: kernel: do not mark reserved memory regions as IORESOURCE_BUSY

2017-01-26T12:15:13+00:00

Memory regions marked as NOMAP should not be used for general allocation
by the kernel, and should not even be covered by the linear mapping
(hence the name). However, drivers or other subsystems (such as ACPI)
that access the firmware directly may legally access them, which means
it is also reasonable for such drivers to claim them by invoking
request_resource(). Currently, this is prevented by the fact that arm64's
request_standard_resources() marks reserved regions as IORESOURCE_BUSY.

So drop the IORESOURCE_BUSY flag from these requests.

Reported-by: Hanjun Guo 
Signed-off-by: Ard Biesheuvel 
Signed-off-by: Will Deacon

arm64: Use __pa_symbol for empty_zero_page

2017-01-26T12:14:50+00:00

If CONFIG_DEBUG_VIRTUAL=y and CONFIG_ARM64_SW_TTBR0_PAN=y:

    virt_to_phys used for non-linear address: ffffff8008cc0000 (empty_zero_page+0x0/0x1000)
    WARNING: CPU: 0 PID: 0 at arch/arm64/mm/physaddr.c:14 __virt_to_phys+0x28/0x60
    ...
    [] __virt_to_phys+0x28/0x60
    [] setup_arch+0x46c/0x4d4

Fixes: 2077be6783b5936c ("arm64: Use __pa_symbol for kernel symbols")
Acked-by: Mark Rutland 
Acked-by: Laura Abbott 
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Will Deacon

arm64: Use __pa_symbol for kernel symbols

2017-01-12T15:05:39+00:00

__pa_symbol is technically the marcro that should be used for kernel
symbols. Switch to this as a pre-requisite for DEBUG_VIRTUAL which
will do bounds checking.

Reviewed-by: Mark Rutland 
Tested-by: Mark Rutland 
Signed-off-by: Laura Abbott 
Signed-off-by: Will Deacon

arm64: setup: introduce kaslr_offset()

2016-12-20T17:48:46+00:00

Introduce kaslr_offset() similar to x86_64 to fix kcov.

[ Updated by Will Deacon ]

Link: http://lkml.kernel.org/r/1481417456-28826-2-git-send-email-alex.popov@linux.com
Signed-off-by: Alexander Popov 
Cc: Catalin Marinas 
Cc: Ard Biesheuvel 
Cc: Mark Rutland 
Cc: Rob Herring 
Cc: Kefeng Wang 
Cc: AKASHI Takahiro 
Cc: Jon Masters 
Cc: David Daney 
Cc: Ganapatrao Kulkarni 
Cc: Dmitry Vyukov 
Cc: Nicolai Stange 
Cc: James Morse 
Cc: Andrey Ryabinin 
Cc: Andrey Konovalov 
Cc: Alexander Popov 
Cc: syzkaller 
Signed-off-by: Andrew Morton 
Signed-off-by: Will Deacon 
Signed-off-by: Linus Torvalds

arm64: Disable TTBR0_EL1 during normal kernel execution

2016-11-21T18:48:54+00:00

When the TTBR0 PAN feature is enabled, the kernel entry points need to
disable access to TTBR0_EL1. The PAN status of the interrupted context
is stored as part of the saved pstate, reusing the PSR_PAN_BIT (22).
Restoring access to TTBR0_EL1 is done on exception return if returning
to user or returning to a context where PAN was disabled.

Context switching via switch_mm() must defer the update of TTBR0_EL1
until a return to user or an explicit uaccess_enable() call.

Special care needs to be taken for two cases where TTBR0_EL1 is set
outside the normal kernel context switch operation: EFI run-time
services (via efi_set_pgd) and CPU suspend (via cpu_(un)install_idmap).
Code has been added to avoid deferred TTBR0_EL1 switching as in
switch_mm() and restore the reserved TTBR0_EL1 when uninstalling the
special TTBR0_EL1.

User cache maintenance (user_cache_maint_handler and
__flush_cache_user_range) needs the TTBR0_EL1 re-instated since the
operations are performed by user virtual address.

This patch also removes a stale comment on the switch_mm() function.

Cc: Will Deacon 
Cc: James Morse 
Cc: Kees Cook 
Cc: Mark Rutland 
Signed-off-by: Catalin Marinas

arm64: Set UTS_MACHINE in the Makefile

2016-08-31T11:31:38+00:00

The make rpm target depends on proper UTS_MACHINE definition.  Also, use
the variable in arch/arm64/kernel/setup.c, so that it's not accidentally
removed in the future.

Reported-and-tested-by: Fabian Vogt 
Signed-off-by: Michal Marek 
Signed-off-by: Will Deacon

arm64: mark reserved memblock regions explicitly in iomem

2016-08-25T17:00:31+00:00

Kdump(kexec-tools) parses /proc/iomem to identify all the memory regions
on the system. Since the current kernel names "nomap" regions, like UEFI
runtime services code/data, as "System RAM," kexec-tools sets up elf core
header to include them in a crash dump file (/proc/vmcore).

Then crash dump kernel parses UEFI memory map again, re-marks those regions
as "nomap" and does not create a memory mapping for them unlike the other
areas of System RAM. In this case, copying /proc/vmcore through
copy_oldmem_page() on crash dump kernel will end up with a kernel abort,
as reported in [1].

This patch names all the "nomap" regions explicitly as "reserved" so that
we can exclude them from a crash dump file. acpi_os_ioremap() must also
be modified because those regions have WB attributes [2].

Apart from kdump, this change also matches x86's use of acpi (and
/proc/iomem).

[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2016-August/448186.html
[2] http://lists.infradead.org/pipermail/linux-arm-kernel/2016-August/450089.html

Reviewed-by: Catalin Marinas 
Tested-by: James Morse 
Reviewed-by: James Morse 
Signed-off-by: AKASHI Takahiro 
Signed-off-by: Will Deacon