One of the nice ideas behind paravirt is that CONFIG_XEN=y can be included
in a standard configuration and be no worse for native booting than as a
Xen guest. The glibc feature that supports the vDSO "nosegneg" note is
designed specifically to make this easy. You just have to flip one bit at
boot time. This patch makes Xen flip the bit, so a CONFIG_XEN=y kernel on
bare hardware does not make glibc use the less-optimized library builds.
Signed-off-by: Roland McGrath <roland@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With the new setup code, we generate a couple more files
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
[ .. and do the same for x86-64 - Alexey ]
Acked-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Keep the arch/i386/boot directory from being rebuilt every time.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
There exists at least one card, Trident TVGA8900CL (BIOS dated 1992/9/8)
which clobbers DS when "scrolling in an SVGA text mode of more than
800x600 pixels." Although we are extremely unlikely to run into that
situation, it is cheap insurance to save and restore DS, and it only adds
a grand total of 50 bytes to the total output.
Pointed out by Etienne Lorrain.
Cc: Etienne Lorrain <etienne_lorrain@yahoo.fr>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
If the user has asked for the vertical height registers to be recomputed
by setting bit 15 in the video mode number, we do so without clearing the
Protect bit in the Vertical Retrace Register before setting the Overflow
register. As a result, if the VGA BIOS had set the Protect bit, the
write to the Overflow register will be dropped, and bits [9:8] of the
vertical height will be left unchanged.
This is a bug imported from the assembly version of this code. It was
pointed out by Etienne Lorrain.
Cc: Etienne Lorrain <etienne_lorrain@yahoo.fr>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Fix incorrect assembly constraints. In particular, fix memory
constraints used inside push..pop, which can cause invalid operation
since gcc may generate %esp-relative references.
Additionally:
outl() should have "dN" not "dn".
query_mca() shouldn't listen 16/32-bit registers in an 8-bit only
context.
has_eflag(): the "mask" is only used well after both the stack pointer
and the output registers have been touched; this requires the output
registers to be earlyclobbers (=&) and the input to exclude memory (so
"ri", not "g").
Thanks to Etienne Lorrain and Chuck Ebbert for prompting this review.
Cc: Etienne Lorrain <etienne_lorrain@yahoo.fr>
Cc: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Correct a comment in arch/i386/boot/build/tools.c; we now build the
kernel from only two components instead of three, since the boot
sector has been integrated in the setup code.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
arch/i386/xen/xen-asm.S defines some small pieces of code which are
used to implement a few paravirt_ops. They're designed so they can be
used either in-place, or be inline patched into their callsites if
there's enough space.
Some of those operations need to make calls out (specifically, if you
re-enable events [interrupts], and there's a pending event at that
time). These calls need the call instruction to be relocated if the
code is patched inline. In this case xen_foo_reloc is a
section-relative symbol which points to xen_foo's required relocation.
Other operations have no need of a relocation, and so their
corresponding xen_bar_reloc is absolute 0. These are the cases which
are triggering the warning.
This patch adds those symbols to the list of safe abs symbols.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Adrian Bunk <bunk@stusta.de>
This removes the old i386 setup code. This is done as a separate patch
to avoid breaking git bisect as some of the i386 code was also used by
the old x86-64 code.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch hooks the new x86 setup code into the Makefile machinery. It
also adapts boot/tools/build.c to a two-file (as opposed to three-file)
universe, and simplifies it substantially.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linker script to define the layout of the new x86 setup code.
Includes assert for size overflow and a misaligned setup header.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The assembly header and initialization code, and the main() routine.
main.c also contains some miscellaneous very short routines.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the code which actually does the switch to protected mode,
including all preparation. It is also responsible for invoking the
boot loader hooks, if present.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Video mode probing for the new x86 setup code. This code breaks down
different drivers into modules. This code deliberately drops support
for a lot of the vendor-specific mode probing present in the assembly
version, since a lot of those probes have been found to be stale in
current versions of those chips -- frequently, support for those modes
have been dropped from recent video BIOSes due to space constraints,
but the video BIOS signatures are still the same.
However, additional drivers should be extremely straightforward to plug
in, if desirable.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Voyager support for the new x86 setup code. This implements the same
functionality as the assembly version.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
MCA probing support for the new x86 setup code. This implements the
same functionality as the assembly version.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Probe EDD and MBR signatures, in order to make it easier to map
physical hard drives to BIOS drives.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Verify that the CPU has enough features to run the kernel. This may
entail enabling features on some CPUs.
By doing this in the setup code we can be guaranteed to still be able to
write to the console through the BIOS.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Module which only includes the kernel version string.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This implements writing text to the console, including printf().
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Simple command-line parser which allows us to access the kernel command
line from the setup code.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
APM probing code for the new x86 setup code. This implements the
same functionality as the assembly version.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A20 handling code for the new x86 setup code. This implements the same
algorithms as the assembly version.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
strcmp(), memcpy(), memset(), as well as routines to copy to and from
other segments (as pointed to by fs and gs).
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A simple collection of bitops for the new x86 setup code.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Top header file for the new x86 setup code.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc for i386 can be used with the assembly prefix ".code16gcc" to generate
16-bit (real-mode) code. This header file provides the assembly prefix.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The relocatable kernel code needs a scratch field for the decompressor
to determine its own location. It was using a location inside
struct screen_info; reserve a free location and document it as scratch
instead.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- boot/setup.S did not print "PANIC: CPU too old for this kernel"
( not visible, also the message did not match )
- I add "# missed before: set ds"
=> somebody should check if I am right with the way to set.
=> seems to be a generic error in setup.S not to set "ds" for error messages.
AK: extracted patch out of other changes
AK: also couldn't find any other case where ds is wrong
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 464bdd33e9.
Peter Anvin correctly points out that VESA modes have nothing to do with
frame buffers per se - they are often just regular extended text modes.
Disabling them just because we don't have frame buffer support is very
wrong.
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Antonino A. Daplas <adaplas@gmail.com>,
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the option vga=<VESA graphics mode> is added to the boot parameter, it will
activate graphics mode, but without any framebuffer support, the user is left
with an unusable display.
Change the behavior such that the user is instead prompted for another mode
(ala vga=ask).
NOTE: People can always use vbetool to set a graphics mode if this is really
desired, but the number of people doing this approaches zero.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Check some CPUID bits that are needed for compiler generated early in boot.
When the system is still in real mode before changing the VESA BIOS mode
it is possible to still display an visible error message on the screen.
Similar to x86-64.
Includes cleanups from Eric Biederman
Signed-off-by: Andi Kleen <ak@suse.de>
inflate_fixed and huft_build together use around 2.7k of stack. When
using 4k stacks, I saw stack overflows from interrupts arriving while
unpacking the root initrd:
do_IRQ: stack overflow: 384
[<c0106b64>] show_trace_log_lvl+0x1a/0x30
[<c01075e6>] show_trace+0x12/0x14
[<c010763f>] dump_stack+0x16/0x18
[<c0107ca4>] do_IRQ+0x6d/0xd9
[<c010202b>] xen_evtchn_do_upcall+0x6e/0xa2
[<c0106781>] xen_hypervisor_callback+0x25/0x2c
[<c010116c>] xen_restore_fl+0x27/0x29
[<c0330f63>] _spin_unlock_irqrestore+0x4a/0x50
[<c0117aab>] change_page_attr+0x577/0x584
[<c0117b45>] kernel_map_pages+0x8d/0xb4
[<c016a314>] cache_alloc_refill+0x53f/0x632
[<c016a6c2>] __kmalloc+0xc1/0x10d
[<c0463d34>] malloc+0x10/0x12
[<c04641c1>] huft_build+0x2a7/0x5fa
[<c04645a5>] inflate_fixed+0x91/0x136
[<c04657e2>] unpack_to_rootfs+0x5f2/0x8c1
[<c0465acf>] populate_rootfs+0x1e/0xe4
(This was under Xen, but there's no reason it couldn't happen on bare
hardware.)
This patch mallocs the local variables, thereby reducing the stack
usage to sane levels.
Also, up the heap size for the kernel decompressor to deal with the
extra allocation.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Tim Yamin <plasmaroo@gentoo.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Because the command line is increased to 2048 characters after 2.6.21, it's
not possible for boot loaders and userspace tools to determine the length
of the command line the kernel can understand. The benefit of knowing the
length is that users can be warned if the command line size is too long
which prevents surprise if things don't work after bootup.
This patch updates the boot protocol to contain a field called
"cmdline_size" that contain the length of the command line (excluding the
terminating zero).
The patch also adds missing fields (of protocol version 2.05) to the x86_64
setup code.
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Alon Bar-Lev <alon.barlev@gmail.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
VBE1.2 doesn't support function 15h (DDC) resulting in a 'hang' whilst
uncompressing kernel with some video cards. Make sure we check VBE version
before fiddling around with DDC.
http://bugzilla.kernel.org/show_bug.cgi?id=1458
Opened: 2003-10-30 09:12 Last update: 2007-02-13 22:03
Much thanks to Tobias Hain for help in testing and investigating the bug.
Tested on;
i386, Chips & Technologies 65548 VESA VBE 1.2
CONFIG_VIDEO_SELECT=Y
CONFIG_FIRMWARE_EDID=Y
Untested on x86_64.
Signed-off-by: Zwane Mwaikambo <zwane@infradead.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Change the explicit code in the relocs.c file to use ARRAY_SIZE()
and add a definition of ARRAY_SIZE() since this is a userspace program
and wouldn't include kernel.h.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
i386 boot/compressed/relocs checks for absolute symbols and warns about
unexpected ones. If you build with modversions, you get ~2500 warnings
about __crc_<symbol>. These suckers are really absolute symbols - we
do _not_ want to modify them on relocation.
They are generated by genksyms - EXPORT_... generates a weak alias, then
genksyms produces an ld script with __crc_<symbol> = <checksum> and it's
fed to ld to produce the final object file. Their only use is to match
kernel and module at modprobe time; they _must_ be absolute.
boot/compressed/relocs has a whitelist of known absolute symbols, but
it doesn't know about __crc_... stuff. As the result, we get shitloads
of false positives on any ld(1) version.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 968de4f026 ("i386: Relocatable
kernel support") caused problems for people with old binutils versions
that didn't mark ".text.*" sections automatically allocated.
So we should use .section command to specifically mark .text.head
section as AX (allocatable and executable) to solve the problem.
This should be unnecessary with binutils 2.15 and later, which is
already three years old, but it doesn't hurt supporting older toolchains
where possible.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Due to the changes to make the kernel relocateable a new file is created
during the build process.
[jirislaby@gmail.com: The .gitigonre was intended to be in arch/ subtree]
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Create a paravirt.h header for all the critical operations which need to be
replaced with hypervisor calls, and include that instead of defining native
operations, when CONFIG_PARAVIRT.
This patch does the dumbest possible replacement of paravirtualized
instructions: calls through a "paravirt_ops" structure. Currently these are
function implementations of native hardware: hypervisors will override the ops
structure with their own variants.
All the pv-ops functions are declared "fastcall" so that a specific
register-based ABI is used, to make inlining assember easier.
And:
+From: Andy Whitcroft <apw@shadowen.org>
The paravirt ops introduce a 'weak' attribute onto memory_setup().
Code ordering leads to the following warnings on x86:
arch/i386/kernel/setup.c:651: warning: weak declaration of
`memory_setup' after first use results in unspecified behavior
Move memory_setup() to avoid this.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Zachary Amsden <zach@vmware.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Extend bzImage protocol to enable bootloaders to load a completely relocatable
bzImage. Now protected mode component of kernel is also relocatable and a
boot-loader can load the protected mode component at a differnt physical
address than 1MB. (If kernel was built with CONFIG_RELOCATABLE)
Kexec can make use of it to load this kernel at a different physical address
to capture kernel crash dumps.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
o Now CONFIG_PHYSICAL_START is being replaced with CONFIG_PHYSICAL_ALIGN.
Hardcoding the kernel physical start value creates a problem in relocatable
kernel context due to boot loader limitations. For ex, if somebody
compiles a relocatable kernel to be run from address 4MB, but this kernel
will run from location 1MB as grub loads the kernel at physical address
1MB. Kernel thinks that I am a relocatable kernel and I should run from
the address I have been loaded at. So somebody wanting to run kernel
from 4MB alignment location (for improved performance regions) can't do
that.
o Hence, Eric proposed that probably CONFIG_PHYSICAL_ALIGN will make
more sense in relocatable kernel context. At run time kernel will move
itself to a physical addr location which meets user specified alignment
restrictions.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
o Relocations generated w.r.t absolute symbols are not processed as by
definition, absolute symbols are not to be relocated. Explicitly warn
user about absolutions relocations present at compile time.
o These relocations get introduced either due to linker optimizations or
some programming oversights.
o Also create a list of symbols which have been audited to be safe and
don't emit warnings for these.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
This patch modifies the i386 kernel so that if CONFIG_RELOCATABLE is
selected it will be able to be loaded at any 4K aligned address below
1G. The technique used is to compile the decompressor with -fPIC and
modify it so the decompressor is fully relocatable. For the main
kernel relocations are generated. Resulting in a kernel that is relocatable
with no runtime overhead and no need to modify the source code.
A reserved 32bit word in the parameters has been assigned
to serve as a stack so we figure out where are running.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Defining __PHYSICAL_START and __KERNEL_START in asm-i386/page.h works but
it triggers a full kernel rebuild for the silliest of reasons. This
modifies the users to directly use CONFIG_PHYSICAL_START and linux/config.h
which prevents the full rebuild problem, which makes the code much
more maintainer and hopefully user friendly.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
During tracking down a PAE compile failure, I found that config.h was being
included in a bunch of places in i386 code. It is no longer necessary, so
drop it.
Signed-off-by: Zachary Amsden <zach@vmware.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The EDD code would scan the command line as a fixed array, without
taking account of either whitespace, null-termination, the old
command-line protocol, late overrides early, or the fact that the
command line may not be reachable from INITSEG.
This should fix those problems, and enable us to use a longer command
line.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Andi Kleen <ak@suse.de>
