#ifndef _LIBFDT_ENV_H
#define _LIBFDT_ENV_H
/*
 * libfdt - Flat Device Tree manipulation
 * Copyright (C) 2006 David Gibson, IBM Corporation.
 * Copyright 2012 Kim Phillips, Freescale Semiconductor.
 *
 * libfdt is dual licensed: you can use it either under the terms of
 * the GPL, or the BSD license, at your option.
 *
 *  a) This library is free software; you can redistribute it and/or
 *     modify it under the terms of the GNU General Public License as
 *     published by the Free Software Foundation; either version 2 of the
 *     License, or (at your option) any later version.
 *
 *     This library is distributed in the hope that it will be useful,
 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *     GNU General Public License for more details.
 *
 *     You should have received a copy of the GNU General Public
 *     License along with this library; if not, write to the Free
 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
 *     MA 02110-1301 USA
 *
 * Alternatively,
 *
 *  b) Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *     1. Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *     2. Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stddef.h>
#include <stdint.h>
#include <string.h>

#ifdef __CHECKER__
#define __force __attribute__((force))
#define __bitwise __attribute__((bitwise))
#else
#define __force
#define __bitwise
#endif

typedef uint16_t __bitwise fdt16_t;
typedef uint32_t __bitwise fdt32_t;
typedef uint64_t __bitwise fdt64_t;

#define EXTRACT_BYTE(x, n)	((unsigned long long)((uint8_t *)&x)[n])
#define CPU_TO_FDT16(x) ((EXTRACT_BYTE(x, 0) << 8) | EXTRACT_BYTE(x, 1))
#define CPU_TO_FDT32(x) ((EXTRACT_BYTE(x, 0) << 24) | (EXTRACT_BYTE(x, 1) << 16) | \
			 (EXTRACT_BYTE(x, 2) << 8) | EXTRACT_BYTE(x, 3))
#define CPU_TO_FDT64(x) ((EXTRACT_BYTE(x, 0) << 56) | (EXTRACT_BYTE(x, 1) << 48) | \
			 (EXTRACT_BYTE(x, 2) << 40) | (EXTRACT_BYTE(x, 3) << 32) | \
			 (EXTRACT_BYTE(x, 4) << 24) | (EXTRACT_BYTE(x, 5) << 16) | \
			 (EXTRACT_BYTE(x, 6) << 8) | EXTRACT_BYTE(x, 7))

static inline uint16_t fdt16_to_cpu(fdt16_t x)
{
	return (__force uint16_t)CPU_TO_FDT16(x);
}
static inline fdt16_t cpu_to_fdt16(uint16_t x)
{
	return (__force fdt16_t)CPU_TO_FDT16(x);
}

static inline uint32_t fdt32_to_cpu(fdt32_t x)
{
	return (__force uint32_t)CPU_TO_FDT32(x);
}
static inline fdt32_t cpu_to_fdt32(uint32_t x)
{
	return (__force fdt32_t)CPU_TO_FDT32(x);
}

static inline uint64_t fdt64_to_cpu(fdt64_t x)
{
	return (__force uint64_t)CPU_TO_FDT64(x);
}
static inline fdt64_t cpu_to_fdt64(uint64_t x)
{
	return (__force fdt64_t)CPU_TO_FDT64(x);
}
#undef CPU_TO_FDT64
#undef CPU_TO_FDT32
#undef CPU_TO_FDT16
#undef EXTRACT_BYTE

#endif /* _LIBFDT_ENV_H */
n value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;</td><td class='right'>2017-02-01 17:45:02 +0000</td></tr>
<tr><th>committer</th><td>Ingo Molnar &lt;mingo@kernel.org&gt;</td><td class='right'>2017-02-01 21:17:49 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/kernel/cpu.c?h=nds-private-remove&amp;id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>c8f325a59cfc718d13a50fbc746ed9b415c25e92</a> (<a href='/cgit.cgi/linux/net-next.git/patch/kernel/cpu.c?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>d53fbdac9d0781e39a13b2ac6b2bd258cf3b4140</a> /<a href='/cgit.cgi/linux/net-next.git/tree/kernel/cpu.c?h=nds-private-remove&amp;id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>kernel/cpu.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/kernel/cpu.c?h=nds-private-remove&amp;id=bf29bddf0417a4783da3b24e8c9e017ac649326f'>bf29bddf0417a4783da3b24e8c9e017ac649326f</a> (<a href='/cgit.cgi/linux/net-next.git/diff/kernel/cpu.c?h=nds-private-remove&amp;id=c8f325a59cfc718d13a50fbc746ed9b415c25e92&amp;id2=bf29bddf0417a4783da3b24e8c9e017ac649326f'>diff</a>)</td></tr></table>
<div class='commit-subject'>efi/fdt: Avoid FDT manipulation after ExitBootServices()</div><div class='commit-msg'>Some AArch64 UEFI implementations disable the MMU in ExitBootServices(),
after which unaligned accesses to RAM are no longer supported.

Commit:

  abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel")

fixed an issue in the memory map handling of the stub FDT code, but
inadvertently created an issue with such firmware, by moving some
of the FDT manipulation to after the invocation of ExitBootServices().

Given that the stub's libfdt implementation uses the ordinary, accelerated
string functions, which rely on hardware handling of unaligned accesses,
manipulating the FDT with the MMU off may result in alignment faults.

So fix the situation by moving the update_fdt_memmap() call into the
callback function invoked by efi_exit_boot_services() right before it
calls the ExitBootServices() UEFI service (which is arguably a better
place for it anyway)

Note that disabling the MMU in ExitBootServices() is not compliant with
the UEFI spec, and carries great risk due to the fact that switching from
cached to uncached memory accesses halfway through compiler generated code
(i.e., involving a stack) can never be done in a way that is architecturally
safe.

Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel")
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Tested-by: Riku Voipio &lt;riku.voipio@linaro.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Cc: mark.rutland@arm.com
Cc: linux-efi@vger.kernel.org
Cc: matt@codeblueprint.co.uk
Cc: leif.lindholm@linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>Diffstat</a> (limited to 'kernel/cpu.c')</div><table summary='diffstat' class='diffstat'>