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2015-02-19x86/asm/boot: Use already defined KEEP_SEGMENTS macro in head_{32,64}.SAlexander Kuleshov
There is already defined macro KEEP_SEGMENTS in <asm/bootparam.h>, let's use it instead of hardcoded constants. Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1424331298-7456-1-git-send-email-kuleshovmail@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-11-01x86, kaslr: Prevent .bss from overlaping initrdJunjie Mao
When choosing a random address, the current implementation does not take into account the reversed space for .bss and .brk sections. Thus the relocated kernel may overlap other components in memory. Here is an example of the overlap from a x86_64 kernel in qemu (the ranges of physical addresses are presented): Physical Address 0x0fe00000 --+--------------------+ <-- randomized base / | relocated kernel | vmlinux.bin | (from vmlinux.bin) | 0x1336d000 (an ELF file) +--------------------+-- \ | | \ 0x1376d870 --+--------------------+ | | relocs table | | 0x13c1c2a8 +--------------------+ .bss and .brk | | | 0x13ce6000 +--------------------+ | | | / 0x13f77000 | initrd |-- | | 0x13fef374 +--------------------+ The initrd image will then be overwritten by the memset during early initialization: [ 1.655204] Unpacking initramfs... [ 1.662831] Initramfs unpacking failed: junk in compressed archive This patch prevents the above situation by requiring a larger space when looking for a random kernel base, so that existing logic can effectively avoids the overlap. [kees: switched to perl to avoid hex translation pain in mawk vs gawk] [kees: calculated overlap without relocs table] Fixes: 82fa9637a2 ("x86, kaslr: Select random position from e820 maps") Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Junjie Mao <eternal.n08@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Matt Fleming <matt.fleming@intel.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1414762838-13067-1-git-send-email-eternal.n08@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-09-22Revert "x86/efi: Fixup GOT in all boot code paths"Linus Torvalds
This reverts commit 9cb0e394234d244fe5a97e743ec9dd7ddff7e64b. It causes my Sony Vaio Pro 11 to immediately reboot at startup. Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Anvin <hpa@zytor.com> Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-09-08x86/efi: Fixup GOT in all boot code pathsMatt Fleming
Maarten reported that his Macbook pro 8.2 stopped booting after commit f23cf8bd5c1f49 ("efi/x86: efistub: Move shared dependencies to <asm/efi.h>"), the main feature of which is changing the visibility of symbol 'efi_early' from local to global. By making 'efi_early' global we end up requiring an entry in the Global Offset Table. Unfortunately, while we do include code to fixup GOT entries in the early boot code, it's only called after we've executed the EFI boot stub. What this amounts to is that references to 'efi_early' in the EFI boot stub don't point to the correct place. Since we've got multiple boot entry points we need to be prepared to fixup the GOT in multiple places, while ensuring that we never do it more than once, otherwise the GOT entries will still point to the wrong place. Reported-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Tested-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-10x86/efi: Correct EFI boot stub use of code32_startMatt Fleming
code32_start should point at the start of the protected mode code, and *not* at the beginning of the bzImage. This is much easier to do in assembly so document that callers of make_boot_params() need to fill out code32_start. The fallout from this bug is that we would end up relocating the image but copying the image at some offset, resulting in what appeared to be memory corruption. Reported-by: Thomas Bächler <thomas@archlinux.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-05x86/boot: Fix non-EFI buildMatt Fleming
The kbuild test robot reported the following errors, introduced with commit 54b52d872680 ("x86/efi: Build our own EFI services pointer table"), arch/x86/boot/compressed/head_32.o: In function `efi32_config': >> (.data+0x58): undefined reference to `efi_call_phys' arch/x86/boot/compressed/head_64.o: In function `efi64_config': >> (.data+0x90): undefined reference to `efi_call6' Wrap the efi*_config structures in #ifdef CONFIG_EFI_STUB so that we don't make references to EFI functions if they're not compiled in. Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04x86/efi: Firmware agnostic handover entry pointsMatt Fleming
The EFI handover code only works if the "bitness" of the firmware and the kernel match, i.e. 64-bit firmware and 64-bit kernel - it is not possible to mix the two. This goes against the tradition that a 32-bit kernel can be loaded on a 64-bit BIOS platform without having to do anything special in the boot loader. Linux distributions, for one thing, regularly run only 32-bit kernels on their live media. Despite having only one 'handover_offset' field in the kernel header, EFI boot loaders use two separate entry points to enter the kernel based on the architecture the boot loader was compiled for, (1) 32-bit loader: handover_offset (2) 64-bit loader: handover_offset + 512 Since we already have two entry points, we can leverage them to infer the bitness of the firmware we're running on, without requiring any boot loader modifications, by making (1) and (2) valid entry points for both CONFIG_X86_32 and CONFIG_X86_64 kernels. To be clear, a 32-bit boot loader will always use (1) and a 64-bit boot loader will always use (2). It's just that, if a single kernel image supports (1) and (2) that image can be used with both 32-bit and 64-bit boot loaders, and hence both 32-bit and 64-bit EFI. (1) and (2) must be 512 bytes apart at all times, but that is already part of the boot ABI and we could never change that delta without breaking existing boot loaders anyhow. Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04x86/efi: Build our own EFI services pointer tableMatt Fleming
It's not possible to dereference the EFI System table directly when booting a 64-bit kernel on a 32-bit EFI firmware because the size of pointers don't match. In preparation for supporting the above use case, build a list of function pointers on boot so that callers don't have to worry about converting pointer sizes through multiple levels of indirection. Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-10-13x86, kaslr: Return location from decompress_kernelKees Cook
This allows decompress_kernel to return a new location for the kernel to be relocated to. Additionally, enforces CONFIG_PHYSICAL_START as the minimum relocation position when building with CONFIG_RELOCATABLE. With CONFIG_RANDOMIZE_BASE set, the choose_kernel_location routine will select a new location to decompress the kernel, though here it is presently a no-op. The kernel command line option "nokaslr" is introduced to bypass these routines. Signed-off-by: Kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/1381450698-28710-3-git-send-email-keescook@chromium.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-08-07x86, relocs: Move ELF relocation handling to CKees Cook
Moves the relocation handling into C, after decompression. This requires that the decompressed size is passed to the decompression routine as well so that relocations can be found. Only kernels that need relocation support will use the code (currently just x86_32), but this is laying the ground work for 64-bit using it in support of KASLR. Based on work by Neill Clift and Michael Davidson. Signed-off-by: Kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/20130708161517.GA4832@www.outflux.net Acked-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-01-27x86, build: Dynamically find entry points in compressed startup codeDavid Woodhouse
We have historically hard-coded entry points in head.S just so it's easy to build the executable/bzImage headers with references to them. Unfortunately, this leads to boot loaders abusing these "known" addresses even when they are *explicitly* told that they "should look at the ELF header to find this address, as it may change in the future". And even when the address in question *has* actually been changed in the past, without fanfare or thought to compatibility. Thus we have bootloaders doing stunningly broken things like jumping to offset 0x200 in the kernel startup code in 64-bit mode, *hoping* that startup_64 is still there (it has moved at least once before). And hoping that it's actually a 64-bit kernel despite the fact that we don't give them any indication of that fact. This patch should hopefully remove the temptation to abuse internal addresses in future, where sternly worded comments have not sufficed. Instead of having hard-coded addresses and saying "please don't abuse these", we actually pull the addresses out of the ELF payload into zoffset.h, and make build.c shove them back into the right places in the bzImage header. Rather than including zoffset.h into build.c and thus having to rebuild the tool for every kernel build, we parse it instead. The parsing code is small and simple. This patch doesn't actually move any of the interesting entry points, so any offending bootloader will still continue to "work" after this patch is applied. For some version of "work" which includes jumping into the compressed payload and crashing, if the bzImage it's given is a 32-bit kernel. No change there then. [ hpa: some of the issues in the description are addressed or retconned by the 2.12 boot protocol. This patch has been edited to only remove fixed addresses that were *not* thus retconned. ] Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Link: http://lkml.kernel.org/r/1358513837.2397.247.camel@shinybook.infradead.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Matt Fleming <matt.fleming@intel.com>
2013-01-27x86, efi: Fix 32-bit EFI handover protocol entry pointDavid Woodhouse
If the bootloader calls the EFI handover entry point as a standard function call, then it'll have a return address on the stack. We need to pop that before calling efi_main(), or the arguments will all be out of position on the stack. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Cc: <stable@kernel.org> Link: http://lkml.kernel.org/r/1358513837.2397.247.camel@shinybook.infradead.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Matt Fleming <matt.fleming@intel.com>
2012-07-20x86, efi: Handover ProtocolMatt Fleming
As things currently stand, traditional EFI boot loaders and the EFI boot stub are carrying essentially the same initialisation code required to setup an EFI machine for booting a kernel. There's really no need to have this code in two places and the hope is that, with this new protocol, initialisation and booting of the kernel can be left solely to the kernel's EFI boot stub. The responsibilities of the boot loader then become, o Loading the kernel image from boot media File system code still needs to be carried by boot loaders for the scenario where the kernel and initrd files reside on a file system that the EFI firmware doesn't natively understand, such as ext4, etc. o Providing a user interface Boot loaders still need to display any menus/interfaces, for example to allow the user to select from a list of kernels. Bump the boot protocol number because we added the 'handover_offset' field to indicate the location of the handover protocol entry point. Cc: H. Peter Anvin <hpa@zytor.com> Cc: Peter Jones <pjones@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Acked-and-Tested-by: Matthew Garrett <mjg@redhat.com> Link: http://lkml.kernel.org/r/1342689828-16815-1-git-send-email-matt@console-pimps.org Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-04-16x86, efi: Add dedicated EFI stub entry pointMatt Fleming
The method used to work out whether we were booted by EFI firmware or via a boot loader is broken. Because efi_main() is always executed when booting from a boot loader we will dereference invalid pointers either on the stack (CONFIG_X86_32) or contained in %rdx (CONFIG_X86_64) when searching for an EFI System Table signature. Instead of dereferencing these invalid system table pointers, add a new entry point that is only used when booting from EFI firmware, when we know the pointer arguments will be valid. With this change legacy boot loaders will no longer execute efi_main(), but will instead skip EFI stub initialisation completely. [ hpa: Marking this for urgent/stable since it is a regression when the option is enabled; without the option the patch has no effect ] Signed-off-by: Matt Fleming <matt.hfleming@intel.com> Link: http://lkml.kernel.org/r/1334584744.26997.14.camel@mfleming-mobl1.ger.corp.intel.com Reported-by: Jordan Justen <jordan.l.justen@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org> v3.3
2011-12-12x86, efi: EFI boot stub supportMatt Fleming
There is currently a large divide between kernel development and the development of EFI boot loaders. The idea behind this patch is to give the kernel developers full control over the EFI boot process. As H. Peter Anvin put it, "The 'kernel carries its own stub' approach been very successful in dealing with BIOS, and would make a lot of sense to me for EFI as well." This patch introduces an EFI boot stub that allows an x86 bzImage to be loaded and executed by EFI firmware. The bzImage appears to the firmware as an EFI application. Luckily there are enough free bits within the bzImage header so that it can masquerade as an EFI application, thereby coercing the EFI firmware into loading it and jumping to its entry point. The beauty of this masquerading approach is that both BIOS and EFI boot loaders can still load and run the same bzImage, thereby allowing a single kernel image to work in any boot environment. The EFI boot stub supports multiple initrds, but they must exist on the same partition as the bzImage. Command-line arguments for the kernel can be appended after the bzImage name when run from the EFI shell, e.g. Shell> bzImage console=ttyS0 root=/dev/sdb initrd=initrd.img v7: - Fix checkpatch warnings. v6: - Try to allocate initrd memory just below hdr->inird_addr_max. v5: - load_options_size is UTF-16, which needs dividing by 2 to convert to the corresponding ASCII size. v4: - Don't read more than image->load_options_size v3: - Fix following warnings when compiling CONFIG_EFI_STUB=n arch/x86/boot/tools/build.c: In function ‘main’: arch/x86/boot/tools/build.c:138:24: warning: unused variable ‘pe_header’ arch/x86/boot/tools/build.c:138:15: warning: unused variable ‘file_sz’ - As reported by Matthew Garrett, some Apple machines have GOPs that don't have hardware attached. We need to weed these out by searching for ones that handle the PCIIO protocol. - Don't allocate memory if no initrds are on cmdline - Don't trust image->load_options_size Maarten Lankhorst noted: - Don't strip first argument when booted from efibootmgr - Don't allocate too much memory for cmdline - Don't update cmdline_size, the kernel considers it read-only - Don't accept '\n' for initrd names v2: - File alignment was too large, was 8192 should be 512. Reported by Maarten Lankhorst on LKML. - Added UGA support for graphics - Use VIDEO_TYPE_EFI instead of hard-coded number. - Move linelength assignment until after we've assigned depth - Dynamically fill out AddressOfEntryPoint in tools/build.c - Don't use magic number for GDT/TSS stuff. Requested by Andi Kleen - The bzImage may need to be relocated as it may have been loaded at a high address address by the firmware. This was required to get my macbook booting because the firmware loaded it at 0x7cxxxxxx, which triggers this error in decompress_kernel(), if (heap > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff)) error("Destination address too large"); Cc: Mike Waychison <mikew@google.com> Cc: Matthew Garrett <mjg@redhat.com> Tested-by: Henrik Rydberg <rydberg@euromail.se> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Link: http://lkml.kernel.org/r/1321383097.2657.9.camel@mfleming-mobl1.ger.corp.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-08-02x86, setup: Allow global variables and functions in the decompressorH. Peter Anvin
In order for global variables and functions to work in the decompressor, we need to fix up the GOT in assembly code. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> LKML-Reference: <4C57382E.8050501@zytor.com>
2009-09-18x86: convert compressed loader to use __HEAD and HEAD_TEXT macros.Tim Abbott
This has the consequence of changing the section name use for head code from ".text.head" to ".head.text". Linus suggested that we merge the ".text.head" section with ".text" (presumably while preserving the fact that the head code starts at 0). When I tried this it caused the kernel to not boot. Signed-off-by: Tim Abbott <tabbott@ksplice.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-11x86, boot: make kernel_alignment adjustable; new bzImage fieldsH. Peter Anvin
Make the kernel_alignment field adjustable; this allows us to set it to a large value (intended to be 16 MB to avoid ZONE_DMA contention, memory holes and other weirdness) while a smart bootloader can still force a loading at a lesser alignment if absolutely necessary. Also export pref_address (preferred loading address, corresponding to the link-time address) and init_size, the total amount of linear memory the kernel will require during initialization. [ Impact: allows better kernel placement, gives bootloader more info ] Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-11x86, boot: remove dead code from boot/compressed/head_*.SH. Peter Anvin
Remove a couple of lines of dead code from arch/x86/boot/compressed/head_*.S; all of these update registers that are dead in the current code. [ Impact: cleanup ] Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-08x86, boot: determine compressed code offset at compile timeH. Peter Anvin
Determine the compressed code offset (from the kernel runtime address) at compile time. This allows some minor optimizations in arch/x86/boot/compressed/head_*.S, but more importantly it makes this value available to the build process, which will enable a future patch to export the necessary linear memory footprint into the bzImage header. [ Impact: cleanup, future patch enabling ] Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-08x86, boot: use appropriate rep string for move and clearH. Peter Anvin
In the pre-decompression code, use the appropriate largest possible rep movs and rep stos to move code and clear bss, respectively. For reverse copy, do note that the initial values are supposed to be the address of the first (highest) copy datum, not one byte beyond the end of the buffer. rep strings are not necessarily the fastest way to perform these operations on all current processors, but are likely to be in the future, and perhaps more importantly, we want to encourage the architecturally right thing to do here. This also fixes a couple of trivial inefficiencies on 64 bits. [ Impact: trivial performance enhancement, increase code similarity ] Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-08x86, boot: zero EFLAGS on 32 bitsH. Peter Anvin
The 64-bit code already clears EFLAGS as soon as it has a stack. This seems like a reasonable precaution, so do it on 32 bits as well. [ Impact: extra paranoia ] Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-08x86, boot: set up the decompression stack as early as possibleH. Peter Anvin
Set up the decompression stack as soon as we know where it needs to go. That way we have a full-service stack as soon as possible, rather than relying on the BP_scratch field. Note that the stack does need to be empty during bss zeroing (or else the stack needs to be moved out of the bss segment, which is also an option.) [ Impact: cleanup, minor paranoia ] Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-08x86, boot: straighten out ranges to copy/zero in compressed/head*.SH. Peter Anvin
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>
2009-05-08x86, boot: stylistic cleanups for boot/compressed/head_32.SH. Peter Anvin
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>
2009-05-08x86, boot: use BP_scratch in arch/x86/boot/compressed/head_*.SH. Peter Anvin
Use the BP_scratch symbol from asm-offsets.h instead of hard-coding the location. [ Impact: cleanup ] Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-04-27x86: unify arch/x86/boot/compressed/vmlinux_*.ldsLinus Torvalds
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>
2009-02-20Merge branches 'x86/asm', 'x86/cleanups' and 'x86/headers' into x86/coreIngo Molnar
2009-02-19x86: compressed head_32 - use ENTRY,ENDPROC macrosCyrill Gorcunov
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>
2009-02-13x86: use _types.h headers in asm where availableJeremy Fitzhardinge
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>
2008-08-11x86: fix comment in protected mode headerPhilipp Kohlbecher
Comments in arch/x86/boot/compressed/head_32.S erroneously refer to the real mode pointer as the second and the heap area as the third argument to decompress_kernel(). In fact, these have been the first and second argument, respectively, since v2.6.20. This patch corrects the comments. It introduces no code changes. Signed-off-by: Philipp Kohlbecher <xt28@gmx.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-19x86: cleanup boot-heap usageAlexander van Heukelum
The kernel decompressor wrapper uses memory located beyond the end of the image. This might lead to hard to debug problems, but even if it can be proven to be safe, it is at the very least unclean. I don't see any advantages either, unless you count it not being zeroed out as an advantage. This patch moves the boot-heap area to the bss segment. Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-27x86: Fix boot protocol KEEP_SEGMENTS check.Eric W. Biederman
The kernel only ever supports 1 version of the boot protocol so there is no need to check the boot protocol revision to see if a feature is supported. Both x86 and x86_64 support the same boot protocol so we need to implement the KEEP_SEGMENTS on x86_64 as well. It isn't just paravirt bootloaders that could use this functionality. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Vivek Goyal <vgoyal@in.ibm.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Zachary Amsden <zach@vmware.com> Cc: Andi Kleen <ak@suse.de> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-22i386: paravirt boot sequenceRusty Russell
This patch uses the updated boot protocol to do paravirtualized boot. If the boot version is >= 2.07, then it will do two things: 1. Check the bootparams loadflags to see if we should reload the segment registers and clear interrupts. This is appropriate for normal native boot and some paravirtualized environments, but inapproprate for others. 2. Check the hardware architecture, and dispatch to the appropriate kernel entrypoint. If the bootloader doesn't set this, then we simply do the normal boot sequence. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@in.ibm.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Zachary Amsden <zach@vmware.com> Cc: Andi Kleen <ak@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-11i386: move bootThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>