Both on 32 and 64 bits, we copy all the way up to the end of bss,
except that on 64 bits there is a hack to avoid copying on top of the
page tables. There is no point in copying bss at all, especially
since we are just about to zero it all anyway.
To clean up and unify the handling, we now do:
- copy from startup_32 to _bss.
- zero from _bss to _ebss.
- the _ebss symbol is aligned to an 8-byte boundary.
- the page tables are moved to a separate section.
Use _bss as the copy endpoint since _edata may be misaligned.
[ Impact: cleanup, trivial performance improvement ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Clean up style issues in arch/x86/boot/compressed/head_64.S. This
file had a lot fewer style issues than its 32-bit cousin, but the ones
it has are worth fixing, especially since it makes the two files more
similar.
[ Impact: cleanup, no object code change ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Reformat arch/x86/boot/compressed/head_32.S to be closer to currently
preferred kernel assembly style, that is:
- opcode and operand separated by tab
- operands separated by ", "
- C-style comments
This also makes it more similar to head_64.S.
[ Impact: cleanup, no object code change ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
When generating the compression suffix in
arch/x86/boot/compressed/Makefile, follow standard Kbuild
conventions, that is:
- Use a dash not underscore before y/m/n endings
- Use := whenever possible.
Requested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Simplify the arch/x86/boot/compressed/Makefile, by using the new
capability of specifying multiple inputs to a compressor, and the
CONFIG_X86_NEED_RELOCS Kconfig symbol.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Aligning the .bss section makes it trivial to use large operation
sizes for moving the initialized sections and clearing the .bss.
The alignment chosen (L1 cache) is somewhat arbitrary, but should be
large enough to avoid all known performance traps and small enough to
not cause troubles.
[ Impact: trivial performance enhancement, future patch prep ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Look at the:
diff -u arch/x86/boot/compressed/vmlinux_*.lds
output and realize that they're basially exactly the same except for
trivial naming differences, and the fact that the 64-bit version has a
"pgtable" thing.
So unify them.
There's some trivial cleanup there (make the output format a Kconfig thing
rather than doing #ifdef's for it, and unify both 32-bit and 64-bit BSS
end to "_ebss", where 32-bit used to use the traditional "_end"), but
other than that it's really very mindless and straigt conversion.
For example, I think we should aim to remove "startup_32" vs "startup_64",
and just call it "startup", and get rid of one more difference. I didn't
do that.
Also, notice the comment in the unified vmlinux.lds.S talks about
"head_64" and "startup_32" which is an odd and incorrect mix, but that was
actually what the old 64-bit only lds file had, so the confusion isn't
new, and now that mixing is arguably more accurate thanks to the
vmlinux.lds.S file being shared between the two cases ;)
[ Impact: cleanup, unification ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: Fixes these modes on at least one system
The rewrite of the setup code into C resequenced the font setting and
register reprogramming phases of configuring nonstandard VGA modes
which use 480 scan lines in text mode. However, there exists at least
one board (Micro-Star MS-7383 version 2.0) on which this resequencing
causes an unusable display.
Revert to the original sequencing: set up 480-line mode, install the
font, and then adjust the vertical end register appropriately.
This failure was masked by the fact that the 480-line setup was broken
until checkin 5f64135612 (therefore this
is not a -stable candidate bug fix.)
Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: code size reduction (possibly critical)
The x86 boot and decompression code has no use of the branch profiling
constructs, so disable them. This would bloat the setup code by as
much as 14K, eating up a fairly large chunk of the 32K area we are
guaranteed to have.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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
Impact: fix rarely-used feature
The VGA Miscellaneous Output Register is read from address 0x3CC but
written to address 0x3C2. This was missed when this code was
converted from assembly to C. While we're at it, clean up the code by
making the overflow bits and the math used to set the bits explicit.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup
The setup code is mostly 16-bit code, but there is a small stub of
32-bit code at the end. Move the 32-bit code to a separate segment,
.text32, to avoid scrambling the disassembly.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup
Instead of using CLEAN_FILES in arch/x86/Makefile, add generated files
to targets in arch/x86/boot/Makefile, so they will get naturally
cleaned up by "make clean".
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: cleanup
Remove targets that were used for zImage only, and Makefile
infrastructure that was there to support the zImage/bzImage split.
Reported-by: Paul Bolle <pebolle@tiscali.nl>
LKML-Reference: <1236879901.24144.26.camel@test.thuisdomein>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: obsolete feature removal
The zImage kernel format has been functionally unused for a very long
time. It is just barely possible to build a modern kernel that still
fits within the zImage size limit, but it is highly unlikely that
anyone ever uses it. Furthermore, although it is still supported by
most bootloaders, it has been at best poorly tested (or not tested at
all); some bootloaders are even known to not support zImage at all and
not having even noticed.
Also remove some really obsolete constants that no longer have any
meaning.
LKML-Reference: <49B703D4.1000008@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: remove unused/broken code
The Voyager subarch last built successfully on the v2.6.26 kernel
and has been stale since then and does not build on the v2.6.27,
v2.6.28 and v2.6.29-rc5 kernels.
No actual users beyond the maintainer reported this breakage.
Patches were sent and most of the fixes were accepted but the
discussion around how to do a few remaining issues cleanly
fizzled out with no resolution and the code remained broken.
In the v2.6.30 x86 tree development cycle 32-bit subarch support
has been reworked and removed - and the Voyager code, beyond the
build problems already known, needs serious and significant
changes and probably a rewrite to support it.
CONFIG_X86_VOYAGER has been marked BROKEN then. The maintainer has
been notified but no patches have been sent so far to fix it.
While all other subarchs have been converted to the new scheme,
voyager is still broken. We'd prefer to receive patches which
clean up the current situation in a constructive way, but even in
case of removal there is no obstacle to add that support back
after the issues have been sorted out in a mutually acceptable
fashion.
So remove this inactive code for now.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: clenaup
Linker script will put startup_32 at predefined
address so using startup_32 will not bloat the
code size.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: clenaup
Linker script will put startup_32 at predefined
address so using ENTRY will not bloat the code
size.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
We are in setup stage so we use GLOBAL
instead of ENTRY and do not increase code
size.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In general, the only definitions that assembly files can use
are in _types.S headers (where available), so convert them.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
When probing the keyboard controller to enable A20, if we get FF back
(which is *possible* as a valid status word, but is extremely
unlikely) then bail after much fewer iterations than we otherwise
would, and abort the attempt to access the KBC.
This hopefully should make it work a lot better for embedded platforms
which don't have a KBC and where the BIOS doesn't implement
INT 15h AX=2401h (and doesn't boot with A20 already enabled.)
If this works, it will be the one remaining use of CONFIG_X86_ELAN as
anything other than a processor type optimization option.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: fix potential miscompile (currently believed non-manifest)
As the comment explains, the VBE DDC call can clobber any register.
Tell the compiler about that fact.
Signed-off-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix potential miscompile (currently believed non-manifest)
As the comment explains, the VBE DDC call can clobber any register.
Tell the compiler about that fact.
Signed-off-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: Replaces x86 kernel decompressor with new code
This is the third part of the bzip2/lzma patch
The bzip patch is based on an idea by Christian Ludwig, includes support for
compressing the kernel with bzip2 or lzma rather than gzip. Both
compressors give smaller sizes than gzip. Lzma's decompresses faster
than bzip2.
It also supports ramdisks and initramfs' compressed using these two
compressors.
The functionality has been successfully used for a couple of years by
the udpcast project
This version applies to "tip" kernel 2.6.28
This part contains:
- support for new bzip2 and lzma kernel compression for x86
Signed-off-by: Alain Knaff <alain@knaff.lu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: build fix with certain compilers
GCC can decide to use %dil when "r" is used, which is not valid for
setnz.
This bug was brought out by Stephen Rothwell's merging of the
branch tracer into linux-next.
[ Thanks to Uros Bizjak for recommending 'q' over 'Q' ]
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: make global variables static
Fix these sparse warnings:
arch/x86/boot/video.c:233:3: warning: symbol 'saved' was not declared. Should it be static?
arch/x86/boot/video-vga.c:37:13: warning: symbol 'video_vga' was not declared. Should it be static?
Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: fix section mismatch warning - apic_x2apic_phys
x86: fix section mismatch warning - apic_x2apic_cluster
x86: fix section mismatch warning - apic_x2apic_uv_x
x86: fix section mismatch warning - apic_physflat
x86: fix section mismatch warning - apic_flat
x86: memtest fix use of reserve_early()
x86 syscall.h: fix argument order
x86/tlb_uv: remove strange mc146818rtc include
x86: remove redundant KERN_DEBUG on pr_debug
x86: do_boot_cpu - check if we have ESR register
x86: MAINTAINERS change for AMD microcode patch loader
x86/proc: fix /proc/cpuinfo cpu offline bug
x86: call dmi-quirks for HP Laptops after early-quirks are executed
x86, kexec: fix hang on i386 when panic occurs while console_sem is held
MCE: Don't run 32bit machine checks with interrupts on
x86: SB600: skip IRQ0 override if it is not routed to INT2 of IOAPIC
x86: make variables static
Change header guards named "ASM_X86__*" to "_ASM_X86_*" since:
a. the double underscore is ugly and pointless.
b. no leading underscore violates namespace constraints.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
These variables are only used in their source files, so make them static.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Currently, it is possible to set a graphics VESA mode at boot time via the
vga= parameter even when no framebuffer driver supporting this is
configured. This could lead to the system booting with a black screen,
without a usable console.
Fix this problem by only allowing to set graphics modes at boot time if a
supporting framebuffer driver is configured.
Signed-off-by: Michal Januszewski <spock@gentoo.org>
Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace a magic number with a named constant in the VESA boot code.
Signed-off-by: Michal Januszewski <spock@gentoo.org>
Cc: linux-fbdev-devel@lists.sourceforge.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
After commit 968de4f ("i386: Relocatable kernel support") IMAGE_OFFSET wasn't
actually used anymore in the (current) X86 build system. Now remove its last
traces.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Impact: segfault on build of a 32-bit relocatable kernel
When converting arch/x86/boot/compressed/relocs.c to support unlimited
sections, the computation of sym_strtab in walk_relocs() was done
incorrectly. This causes a segfault for some people when building the
relocatable 32-bit kernel.
Pointed out by Anonymous <pageexec@freemail.hu>.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
