History log of /arch/arm/kernel/machine_kexec.c
Revision Date Author Comments
229aabdcbd25c542f1cb940faa10a7ebfc3064ed 03-Apr-2014 Kees Cook <keescook@chromium.org> UPSTREAM: ARM: mm: allow text and rodata sections to be read-only

This introduces CONFIG_DEBUG_RODATA, making kernel text and rodata
read-only. Additionally, this splits rodata from text so that rodata can
also be NX, which may lead to wasted memory when aligning to SECTION_SIZE.
The read-only areas are made writable during ftrace updates and kexec.

Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Nicolas Pitre <nico@linaro.org>

(cherry picked from commit 80d6b0c2eed2a504f6740cd1f5ea76dc50abfc4d)
Signed-off-by: Kees Cook <keescook@google.com>
Change-Id: I3ff491ba194e5750b6ee84716e4eeed3dbcf1d7d
378691a798e9511030f0e18d88154bedef8f3e77 12-May-2014 Nikolay Borisov <Nikolay.Borisov@arm.com> UPSTREAM: ARM: kexec: Make .text R/W in machine_kexec

With the introduction of Kees Cook's patch to make the kernel .text
read-only the existing method by which kexec works got broken since it
directly pokes some values in the template code, which resides in the
.text section.

The current patch changes the way those values are inserted so that poking
.text section occurs only in machine_kexec (e.g when we are about to nuke
the old kernel and are beyond the point of return). This allows to use
set_kernel_text_rw() to directly patch the values in the .text section.

I had already sent a patch which achieved this but it was significantly
more complicated, so this is a cleaner/straight-forward approach.

Signed-off-by: Nikolay Borisov <Nikolay.Borisov@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
[kees: collapsed kexec_boot_atags (will.daecon)]
[kees: for bisectability, moved set_kernel_text_rw() to RODATA patch]
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Nicolas Pitre <nico@linaro.org>

(cherry picked from commit 42d720d1731a9d7035c2812437c35e271ec4dd78)
Signed-off-by: Kees Cook <keescook@google.com>
Change-Id: I176b498d5a2a439ecad93ddb8a06f3332c216749
56b700fd6f1e49149880fb1b6ffee0dca5be45fb 18-Apr-2014 Liu Hua <sdu.liu@huawei.com> ARM: 8030/1: ARM : kdump : add arch_crash_save_vmcoreinfo

For vmcore generated by LPAE enabled kernel, user space
utility such as crash needs additional infomation to
parse.

So this patch add arch_crash_save_vmcoreinfo as what PAE enabled
i386 linux does.

Cc: <stable@vger.kernel.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Liu Hua <sdu.liu@huawei.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
e2ccba49085ab5d71b092de2a5176eb9b19cc876 25-Nov-2013 Dave Martin <dave.martin@linaro.org> ARM: 7897/1: kexec: Use the right ISA for relocate_new_kernel

Copying a function with memcpy() and then trying to execute the
result isn't trivially portable to Thumb.

This patch modifies the kexec soft restart code to copy its
assembler trampoline relocate_new_kernel() using fncpy() instead,
so that relocate_new_kernel can be in the same ISA as the rest of
the kernel without problems.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Reported-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Tested-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
4f9b4fb7a2091eec339413a460b1665758401828 14-Aug-2013 Vijaya Kumar K <vijay.kilari@gmail.com> ARM: 7815/1: kexec: offline non panic CPUs on Kdump panic

In case of normal kexec kernel load, all cpu's are offlined
before calling machine_kexec().But in case crash panic cpus
are relaxed in machine_crash_nonpanic_core() SMP function
but not offlined.

When crash kernel is loaded with kexec and on panic trigger
machine_kexec() checks for number of cpus online.
If more than one cpu is online machine_kexec() fails to load
with below error

kexec: error: multiple CPUs still online

In machine_crash_nonpanic_core() SMP function, offline CPU
before cpu_relax

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2103f6cba61a8b8bea3fc1b63661d830a2125e76 02-Aug-2013 Stephen Warren <swarren@nvidia.com> ARM: 7807/1: kexec: validate CPU hotplug support

Architectures should fully validate whether kexec is possible as part of
machine_kexec_prepare(), so that user-space's kexec_load() operation can
report any problems. Performing validation in machine_kexec() itself is
too late, since it is not allowed to return.

Prior to this patch, ARM's machine_kexec() was testing after-the-fact
whether machine_kexec_prepare() was able to disable all but one CPU.
Instead, modify machine_kexec_prepare() to validate all conditions
necessary for machine_kexec_prepare()'s to succeed. BUG if the validation
succeeded, yet disabling the CPUs didn't actually work.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
19ab428f4b7988ef3ac727c680efc193ef53ce14 14-Jun-2013 Stephen Warren <swarren@nvidia.com> ARM: 7759/1: decouple CPU offlining from reboot/shutdown

Add comments to machine_shutdown()/halt()/power_off()/restart() that
describe their purpose and/or requirements re: CPUs being active/not.

In machine_shutdown(), replace the call to smp_send_stop() with a call to
disable_nonboot_cpus(). This completely disables all but one CPU, thus
satisfying the requirement that only a single CPU be active for kexec.
Adjust Kconfig dependencies for this change.

In machine_halt()/power_off()/restart(), call smp_send_stop() directly,
rather than via machine_shutdown(); these functions don't need to
completely de-activate all CPUs using hotplug, but rather just quiesce
them.

Remove smp_kill_cpus(), and its call from smp_send_stop().
smp_kill_cpus() was indirectly calling smp_ops.cpu_kill() without calling
smp_ops.cpu_die() on the target CPUs first. At least some implementations
of smp_ops had issues with this; it caused cpu_kill() to hang on Tegra,
for example. Since smp_send_stop() is only used for shutdown, halt, and
power-off, there is no need to attempt any kind of CPU hotplug here.

Adjust Kconfig to reflect that machine_shutdown() (and hence kexec)
relies upon disable_nonboot_cpus(). However, this alone doesn't guarantee
that hotplug will work, or even that hotplug is implemented for a
particular piece of HW that a multi-platform zImage runs on. Hence, add
error-checking to machine_kexec() to determine whether it did work.

Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Zhangfei Gao <zhangfei.gao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2456f44dd7a9aaffc2cd21a13f78198b3d94da08 16-Oct-2012 Aaro Koskinen <aaro.koskinen@iki.fi> ARM: 7555/1: kexec: fix segment memory addresses check

Commit c564df4db85aac8d1d65a56176a0a25f46138064 (ARM: 7540/1: kexec:
Check segment memory addresses) added a safety check with accidentally
reversed condition, and broke kexec functionality on ARM. Fix this.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
c564df4db85aac8d1d65a56176a0a25f46138064 21-Sep-2012 Matthew Leach <matthew.leach@arm.com> ARM: 7540/1: kexec: Check segment memory addresses

Ensure that the memory regions that are set within the segments
correspond to physical contiguous memory regions.

Reviewed-by: Simon Horman <horms@verge.net.au>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
4cabd1d9625c7d88acd143f4021fbef75394f154 21-Sep-2012 Matthew Leach <matthew.leach@arm.com> ARM: 7539/1: kexec: scan for dtb magic in segments

This patch allows a dtb to be passed to a new kernel using the kexec
mechinism.

When loading segments from userspace, scan each segment's first four
bytes for the dtb magic. If this is found set the kexec_boot_atags
parameter to the relocate_kernel code to the phyical address of this
segment.

Reviewed-by: Simon Horman <horms@verge.net.au>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
9f97da78bf018206fb623cd351d454af2f105fe0 28-Mar-2012 David Howells <dhowells@redhat.com> Disintegrate asm/system.h for ARM

Disintegrate asm/system.h for ARM.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Russell King <linux@arm.linux.org.uk>
cc: linux-arm-kernel@lists.infradead.org
9141a003a491c7230d17b9c29677ce2be437b95c 03-Feb-2012 Will Deacon <will.deacon@arm.com> ARM: 7316/1: kexec: EOI active and mask all interrupts in kexec crash path

The kexec machine crash code can be called in interrupt context via a
sysrq trigger made using the magic key combination. If the irq chip
dealing with the serial interrupt is using the fasteoi flow handler,
then we will never EOI the interrupt because the interrupt handler will
be fatal. In the case of a GIC, this results in the crash kernel not
receiving interrupts on that CPU interface.

This patch adds code (based on the PowerPC implementation) to EOI any
pending interrupts on the crash CPU before masking and disabling all
interrupts. Secondary cores are not a problem since they are placed into
a cpu_relax() loop via an IPI.

Reported-by: Lei Wen <leiwen@marvell.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
3bdc3484e8f2b1b219ad0397d81ce4601fbaf76d 06-Jun-2011 Will Deacon <will.deacon@arm.com> ARM: kexec: use soft_restart for branching to the reboot buffer

Now that there is a common way to reset the machine, let's use it
instead of reinventing the wheel in the kexec backend.

Signed-off-by: Will Deacon <will.deacon@arm.com>
5aafec15bdc54cf0722696c95091d7bd674bfcad 01-Nov-2011 Russell King <rmk+kernel@arm.linux.org.uk> ARM: restart: remove argument to setup_mm_for_reboot()

setup_mm_for_reboot() doesn't make use of its argument, so remove it.

Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
abf015f04614a3a7da43d35b55edc90189af4e6a 07-Nov-2011 Russell King <rmk+kernel@arm.linux.org.uk> Revert "ARM: 7098/1: kdump: copy kernel relocation code at the kexec prepare stage"

This reverts commit 2b034922af2caa19df86f0c502e76cb6f6e910f9.

Will Deacon reports:

This is causing kexec to fail.

The symptoms are that the .init.text section is not loaded as part of the
new kernel image, so when we try to do the SMP/UP fixups we hit a whole sea
of poison left there by the previous kernel.

So my guess is that machine_kexec_prepare *is* too early for preparing the
reboot_code_buffer and, unless anybody has a good reason not to, I'd like to
revert the patch causing these problems.

Reported-by: Will Deacon <will.deacon@arm.com>
2b034922af2caa19df86f0c502e76cb6f6e910f9 23-Sep-2011 Lei Wen <adrian.wenl@gmail.com> ARM: 7098/1: kdump: copy kernel relocation code at the kexec prepare stage

This copy really don't need to do at the very second before the kernel
would crash.

Signed-off-by: Lei Wen <leiwen@marvell.com>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
868d172b8ac23070418ec6265195e88e8d5dbe92 02-Feb-2011 Eric Cooper <ecc@cmu.edu> [ARM] add machine-specific hook to machine_kexec

Provide the option to call a machine-specific function
before kexec'ing a new kernel.

Signed-off-by: Eric Cooper <ecc@cmu.edu>
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
b23065313297e750edd57ab6edfd36224826724e 03-Dec-2010 Per Fransson <per.xx.fransson@stericsson.com> ARM: 6522/1: kexec: Add call to non-crashing cores through IPI

When kexec is used to start a crash kernel the other cores
are notified. These non-crashing cores will save their state
in the crash notes and then do nothing.

Signed-off-by: Per Fransson <per.xx.fransson@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ae360a78f41164e7f9c4cf846696b5b6d8dae5c8 31-Jul-2010 Thomas Gleixner <[tglx@linutronix.de]> arm: Disable outer (L2) cache in kexec

kexec does not disable the outer cache before disabling the inner
caches in cpu_proc_fin(). So L2 is enabled across the kexec jump. When
the new kernel enables chaches again, it randomly crashes.

Disabling L2 before calling cpu_proc_fin() cures the problem.

Disabling L2 requires the following new functions: flush_all(),
inv_all() and disable(). Add them to outer_cache_fns and call them
from the kexec code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
3d3f78d752bfada5b6041f2f7bd0833d8bdf7a4a 26-Jul-2010 Russell King <rmk+kernel@arm.linux.org.uk> ARM: call machine_shutdown() from machine_halt(), etc

x86 calls machine_shutdown() from the various machine_*() calls which
take the machine down ready for halting, restarting, etc, and uses
this to bring the system safely to a point where those actions can be
performed. Such actions are stopping the secondary CPUs.

So, change the ARM implementation of these to reflect what x86 does.

This solves kexec problems on ARM SMP platforms, where the secondary
CPUs were left running across the kexec call.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
9ca03a21e320a6bf44559323527aba704bcc8772 26-Jul-2010 Russell King <rmk+kernel@arm.linux.org.uk> ARM: Factor out common code from cpu_proc_fin()

All implementations of cpu_proc_fin() start by disabling interrupts
and then flush caches. Rather than have every processors proc_fin()
implementation do this, move it out into generic code - and move the
cache flush past setup_mm_for_reboot() (so it can benefit from having
caches still enabled.)

This allows cpu_proc_fin() to become independent of the L1/L2 cache
types, and eventually move the L2 cache flushing into the L2 support
code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
c63836204b27faec5a22d4b53692690cb967aaac 10-May-2010 Mika Westerberg <mika.westerberg@iki.fi> ARM: 6118/1: kdump: implement machine_crash_shutdown()

Implement function machine_crash_shutdown() which disables IRQs and
saves machine state to ELF notes structure.

Signed-off-by: Mika Westerberg <ext-mika.1.westerberg@nokia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
e0fc4f97ab6b11594d0b0658ef6cf02bd68f3b4e 09-Feb-2009 Tobias Klauser <tklauser@distanz.ch> [ARM] Storage class should be before const qualifier

The C99 specification states in section 6.11.5:

The placement of a storage-class specifier other than at the beginning of the
declaration specifiers in a declaration is an obsolescent feature.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
fced80c735941fa518ac67c0b61bbe153fb8c050 06-Sep-2008 Russell King <rmk@dyn-67.arm.linux.org.uk> [ARM] Convert asm/io.h to linux/io.h

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
163f6876f5c3ff8215e900b93779e960a56b3694 15-Aug-2008 Huang Ying <ying.huang@intel.com> kexec jump: rename KEXEC_CONTROL_CODE_SIZE to KEXEC_CONTROL_PAGE_SIZE

Rename KEXEC_CONTROL_CODE_SIZE to KEXEC_CONTROL_PAGE_SIZE, because control
page is used for not only code on some platform. For example in kexec
jump, it is used for data and stack too.

[akpm@linux-foundation.org: unbreak powerpc and arm, finish conversion]
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4cd9d6f774c7e0578bbc4409d4490d8f2097d40a 02-Jan-2008 Richard Purdie <rpurdie@rpsys.net> [ARM] 4736/1: Export atags to userspace and allow kexec to use customised atags

Currently, the atags used by kexec are fixed to the ones originally used
to boot the kernel. This is less than ideal as changing the commandline,
initrd and other options would be a useful feature.

This patch exports the atags used for the current kernel to userspace
through an "atags" file in procfs. The presence of the file is
controlled by its own Kconfig option and cleans up several ifdef blocks
into a separate file. The tags for the new kernel are assumed to be at
a fixed location before the kernel image itself. The location of the
tags used to boot the original kernel is unimportant and no longer
saved.

Based on a patch from Uli Luckas <u.luckas@road.de>

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Uli Luckas <u.luckas@road.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
c587e4a6a4d808fd2a1c4e7fb2d5a3a31e300d23 06-Feb-2007 Richard Purdie <rpurdie@rpsys.net> [ARM] 4137/1: Add kexec support

Add kexec support to ARM.

Improvements like commandline handling could be made but this patch gives
basic functional support. It uses the next available syscall number, 347.

Once the syscall number is known, userspace support will be
finalised/submitted to kexec-tools, various patches already exist.

Originally based on a patch by Maxim Syrchin but updated and forward
ported by various people.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>