Linus pointed out that relying on the compiler to pack structures with
enums is fragile not just for the kernel, but for external tooling as
well which might rely on our UAPI headers.
So separate the two from each other: introduce 'struct boot_e820_entry',
which is the boot protocol entry format.
This actually simplifies the code, as e820__update_table() is now never
called directly with boot protocol table entries - we can rely on
append_e820_table() and do a e820__update_table() call afterwards.
( This will allow further simplifications of __e820__update_table(),
but that will be done in a separate patch. )
This change also has the side effect of not modifying the bootparams structure
anymore - which might be useful for debugging. In theory we could even constify
the boot_params structure - at least from the E820 code's point of view.
Remove the uapi/asm/e820/types.h file, as it's not used anymore - all
kernel side E820 types are defined in asm/e820/types.h.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
No change in functionality.
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In line with the rename to 'struct e820_array', harmonize the naming of common e820
table variable names as well:
e820 => e820_array
e820_saved => e820_array_saved
e820_map => e820_array
initial_e820 => e820_array_init
This makes the variable names more consistent and easier to grep for.
No change in functionality.
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The 'e820entry' and 'e820map' names have various annoyances:
- the missing underscore departs from the usual kernel style
and makes the code look weird,
- in the past I kept confusing the 'map' with the 'entry', because
a 'map' is ambiguous in that regard,
- it's not really clear from the 'e820map' that this is a regular
C array.
Rename them to 'struct e820_entry' and 'struct e820_array' accordingly.
( Leave the legacy UAPI header alone but do the rename in the bootparam.h
and e820/types.h file - outside tools relying on these defines should
either adjust their code, or should use the legacy header, or should
create their private copies for the definitions. )
No change in functionality.
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When we use BIOS function e801 to probe memory, we should use ax/bx
(or cx/dx) as a pair, not mix and match. This was a typo during the
translation from assembly code, and breaks at least one set of
machines in the field (which return cx = dx = 0).
Reported-and-tested-by: Chris Samuel <chris@csamuel.org>
Fix-proposed-by: Thomas Meyer <thomas@m3y3r.de>
Link: http://lkml.kernel.org/r/1303566747.12067.10.camel@localhost.localdomain
Remove ACPI 3 E820 extended memory attributes support. At least one
vendor actively set all the flags to zero, but left ECX on return at
24. This bug may be present in other BIOSes.
The breakage functionally means the ACPI 3 flags are probably
completely useless, and that no OS any time soon is going to rely on
their existence. Therefore, drop support completely. We may want to
revisit this question in the future, if we find ourselves actually
needing the flags.
This reverts all or part of the following checkins:
cd670599b7c549e71d07
However, retain the part from the latter commit that copies e820 into
a temporary buffer; that is an unrelated BIOS workaround. Put in a
comment to explain that part.
See https://bugzilla.redhat.com/show_bug.cgi?id=499396 for some
additional information.
[ Impact: detect all memory on affected machines ]
Reported-by: Thomas J. Baker <tjb@unh.edu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Len Brown <len.brown@intel.com>
Cc: Chuck Ebbert <cebbert@redhat.com>
Cc: Kyle McMartin <kmcmartin@redhat.com>
Cc: Matt Domsch <matt_domsch@dell.com>
Impact: BIOS proofing
"Glove box" off BIOS interrupts in the core boot code.
LKML-Reference: <49DE7F79.4030106@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: BIOS bug safety
For pre-ACPI 3 BIOSes, pre-initialize the end of the e820 buffer just
in case the BIOS returns an unchanged %ecx but without actually
touching the ACPI 3 extended flags field.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: ACPI 3 spec compliance, BIOS bug workaround
The ACPI 3 spec added another field to the E820 buffer -- which is
backwards incompatible, since it contains a validity bit.
Furthermore, there has been at least one report of a BIOS which
assumes that the buffer it is pointed at is the same buffer as for the
previous E820 call. Therefore, read the data into a temporary buffer
and copy the standard part of it if and only if the valid bit is set.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: BIOS bugproofing
Since there are BIOSes known to clobber %ebx and %esi for INT 15 E820,
assume there is something out there clobbering %edi and/or %ebp too,
and don't wait for it to fail.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Jordan Hargrave diagnosed a BIOS clobbering %esi in the E820 call.
That particular BIOS has been fixed, but there is a possibility that
this is responsible for other occasional reports of early boot
failure, and it does not hurt to add %esi to the clobbers.
-stable candidate patch.
Cc: Justin Forbes <jmforbes@linuxtx.org>
Signed-off-by: Michael K Johnson <johnsonm@rpath.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: stable@kernel.org
This recent patch
commit c3965bd151
Author: Paul Jackson <pj@sgi.com>
Date: Wed May 14 08:15:34 2008 -0700
x86 boot: proper use of ARRAY_SIZE instead of repeated E820MAX constant
caused these new warnings during a normal build:
In file included from linux-2.6/arch/x86/boot/memory.c:17:
linux-2.6/include/linux/log2.h: In function '__ilog2_u32':
linux-2.6/include/linux/log2.h:34: warning: implicit declaration of function 'fls'
linux-2.6/include/linux/log2.h: In function '__ilog2_u64':
linux-2.6/include/linux/log2.h:42: warning: implicit declaration of function 'fls64'
linux-2.6/include/linux/log2.h: In function '__roundup_pow_of_two ':
linux-2.6/include/linux/log2.h:63: warning: implicit declaration of function 'fls_long'
I tried to fix them in log2.h, but it's difficult because the real mode
environment is completely different from a normal kernel environment. Instead
define an own ARRAY_SIZE macro in boot.h, similar to the other private
macros there.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch is motivated by a subsequent patch which will allow for more
memory map entries on EFI supported systems than can be passed via the x86
legacy BIOS E820 interface. The legacy interface is limited to E820MAX ==
128 memory entries, and that "E820MAX" manifest constant was used as the
size for several arrays and loops over those arrays.
The primary change in this patch is to change code loop sizes over those
arrays from using the constant E820MAX, to using the ARRAY_SIZE() macro
evaluated for the array being looped. That way, a subsequent patch can
change the size of some of these arrays, without breaking this code.
This patch also adds a parameter to the sanitize_e820_map() routine,
which had an implicit size for the array passed it of E820MAX entries.
This new parameter explicitly passes the size of said array. Once again,
this will allow a subsequent patch to change that array size for some
calls to sanitize_e820_map() without breaking the code.
As part of enhancing the sanitize_e820_map() interface this way, I further
combined the unnecessarily distinct x86_32 and x86_64 declarations for
this routine into a single, commonly used, declaration.
This patch in itself should make no difference to the resulting kernel
binary.
[ mingo@elte.hu: merged to -tip ]
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove old comments that include the old arch/i386 directory.
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The proper way to terminate the e820 chain is with %ebx == 0 on the
last legitimate memory block. However, several BIOSes don't do that
and instead return error (CF = 1) when trying to read off the end of
the list. For this error return, %eax doesn't necessarily return the
SMAP signature -- correctly so, since %ah should contain an error code
in this case.
To deal with some particularly broken BIOSes, we clear the entire e820
chain if the SMAP signature is missing in the middle, indicating a
plain insane e820 implementation. However, we need to make the test
for CF = 1 before the SMAP check.
This fixes at least one HP laptop (nc6400) for which none of the
memory-probing methods (e820, e801, 88) functioned fully according to
spec.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Ingo Molnar