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2022-11-02x86/boot: Repair kernel-doc for boot_kstrtoul()Lukas Bulwahn1-1/+1
Adjust the kernel-doc comment to have the proper function name: boot_kstrtoul(). [ bp: Massage commit message. ] Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20221031094835.15923-1-lukas.bulwahn@gmail.com
2020-05-04x86/boot: Add kstrtoul() from lib/Vamshi K Sthambamkadi1-1/+42
Add kstrtoul() to ../boot/ to be used by facilities there too. [ bp: Massage, make _kstrtoul() static. Prepend function names with "boot_". This is a temporary workaround for build errors like: ld: arch/x86/boot/compressed/acpi.o: in function `count_immovable_mem_regions': acpi.c:(.text+0x463): undefined reference to `_kstrtoul' make[2]: *** [arch/x86/boot/compressed/Makefile:117: arch/x86/boot/compressed/vmlinux] Error 1 due to the namespace clash between x86/boot/ and kernel proper. Future reorg will get rid of the linux/linux/ namespace as much as possible so that x86/boot/ can be independent from kernel proper. ] Signed-off-by: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/1587645588-7130-2-git-send-email-vamshi.k.sthambamkadi@gmail.com
2019-08-08x86/purgatory: Do not use __builtin_memcpy and __builtin_memsetNick Desaulniers1-0/+8
Implementing memcpy and memset in terms of __builtin_memcpy and __builtin_memset is problematic. GCC at -O2 will replace calls to the builtins with calls to memcpy and memset (but will generate an inline implementation at -Os). Clang will replace the builtins with these calls regardless of optimization level. $ llvm-objdump -dr arch/x86/purgatory/string.o | tail 0000000000000339 memcpy: 339: 48 b8 00 00 00 00 00 00 00 00 movabsq $0, %rax 000000000000033b: R_X86_64_64 memcpy 343: ff e0 jmpq *%rax 0000000000000345 memset: 345: 48 b8 00 00 00 00 00 00 00 00 movabsq $0, %rax 0000000000000347: R_X86_64_64 memset 34f: ff e0 Such code results in infinite recursion at runtime. This is observed when doing kexec. Instead, reuse an implementation from arch/x86/boot/compressed/string.c. This requires to implement a stub function for warn(). Also, Clang may lower memcmp's that compare against 0 to bcmp's, so add a small definition, too. See also: commit 5f074f3e192f ("lib/string.c: implement a basic bcmp") Fixes: 8fc5b4d4121c ("purgatory: core purgatory functionality") Reported-by: Vaibhav Rustagi <vaibhavrustagi@google.com> Debugged-by: Vaibhav Rustagi <vaibhavrustagi@google.com> Debugged-by: Manoj Gupta <manojgupta@google.com> Suggested-by: Alistair Delva <adelva@google.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Vaibhav Rustagi <vaibhavrustagi@google.com> Cc: stable@vger.kernel.org Link: https://bugs.chromium.org/p/chromium/issues/detail?id=984056 Link: https://lkml.kernel.org/r/20190807221539.94583-1-ndesaulniers@google.com
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497Thomas Gleixner1-3/+1
Based on 1 normalized pattern(s): this file is part of the linux kernel and is made available under the terms of the gnu general public license version 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 28 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.534229504@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-21x86/boot: Restrict header scope to make Clang happyNick Desaulniers1-1/+2
The inclusion of <linux/kernel.h> was causing issue as the definition of __arch_hweight64 from arch/x86/include/asm/arch_hweight.h eventually gets included. The definition is problematic when compiled with -m16 (all code in arch/x86/boot/ is) as the "D" inline assembly constraint is rejected by both compilers when passed an argument of type long long (regardless of signedness, anything smaller is fine). Because GCC performs inlining before semantic analysis, and __arch_hweight64 is dead in this translation unit, GCC does not report any issues at compile time. Clang does the semantic analysis in the front end, before inlining (run in the middle) can determine the code is dead. I consider this another case of PR33587, which I think we can do more work to solve. It turns out that arch/x86/boot/string.c doesn't actually need linux/kernel.h, simply linux/limits.h and linux/compiler.h. Suggested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Cc: bp@alien8.de Cc: niravd@google.com Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Chao Fan <fanc.fnst@cn.fujitsu.com> Cc: Uros Bizjak <ubizjak@gmail.com> Link: https://bugs.llvm.org/show_bug.cgi?id=33587 Link: https://github.com/ClangBuiltLinux/linux/issues/347 Link: https://lkml.kernel.org/r/20190314221458.83047-1-ndesaulniers@google.com
2019-02-01x86/boot: Copy kstrtoull() to boot/string.cChao Fan1-0/+141
Copy kstrtoull() and the other necessary functions from lib/kstrtox.c to boot/string.c so that code in boot/ can use kstrtoull() and the old simple_strtoull() can gradually be phased out. Using div_u64() from math64.h directly will cause the dividend to be handled as a 64-bit value and cause the infamous __divdi3 linker error due to gcc trying to use its library function for the 64-bit division. Therefore, separate the dividend into an upper and lower part. [ bp: Rewrite commit message. ] Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: bhe@redhat.com Cc: caoj.fnst@cn.fujitsu.com Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: indou.takao@jp.fujitsu.com Cc: Ingo Molnar <mingo@redhat.com> Cc: kasong@redhat.com Cc: Kees Cook <keescook@chromium.org> Cc: msys.mizuma@gmail.com Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190123110850.12433-2-fanc.fnst@cn.fujitsu.com
2018-08-02x86/boot: Use CC_SET()/CC_OUT() instead of open coding itUros Bizjak1-2/+3
Remove open-coded uses of set instructions with CC_SET()/CC_OUT(). Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180629142844.15200-1-ubizjak@gmail.com
2017-07-25x86/boot: #undef memcpy() et al in string.cMichael Davidson1-0/+9
undef memcpy() and friends in boot/string.c so that the functions defined here will have the correct names, otherwise we end up up trying to redefine __builtin_memcpy() etc. Surprisingly, GCC allows this (and, helpfully, discards the __builtin_ prefix from the function name when compiling it), but clang does not. Adding these #undef's appears to preserve what I assume was the original intent of the code. Signed-off-by: Michael Davidson <md@google.com> Signed-off-by: Matthias Kaehlcke <mka@chromium.org> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bernhard.Rosenkranzer@linaro.org Cc: Greg Hackmann <ghackmann@google.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170724235155.79255-1-mka@chromium.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-24x86/KASLR: Parse all 'memmap=' boot option entriesBaoquan He1-0/+8
In commit: f28442497b5c ("x86/boot: Fix KASLR and memmap= collision") ... the memmap= option is parsed so that KASLR can avoid those reserved regions. It uses cmdline_find_option() to get the value if memmap= is specified, however the problem is that cmdline_find_option() can only find the last entry if multiple memmap entries are provided. This is not correct. Address this by checking each command line token for a "memmap=" match and parse each instance instead of using cmdline_find_option(). Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Cc: douly.fnst@cn.fujitsu.com Cc: dyoung@redhat.com Cc: m.mizuma@jp.fujitsu.com Link: http://lkml.kernel.org/r/1494654390-23861-2-git-send-email-bhe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28Merge branch 'linus' into x86/boot, to pick up fixesIngo Molnar1-0/+1
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-25x86/boot: Fix KASLR and memmap= collisionDave Jiang1-0/+13
CONFIG_RANDOMIZE_BASE=y relocates the kernel to a random base address. However it does not take into account the memmap= parameter passed in from the kernel command line. This results in the kernel sometimes being put in the middle of memmap. Teach KASLR to not insert the kernel in memmap defined regions. We support up to 4 memmap regions: any additional regions will cause KASLR to disable. The mem_avoid set has been augmented to add up to 4 unusable regions of memmaps provided by the user to exclude those regions from the set of valid address range to insert the uncompressed kernel image. The nn@ss ranges will be skipped by the mem_avoid set since it indicates that memory is useable. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Baoquan He <bhe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: dan.j.williams@intel.com Cc: david@fromorbit.com Cc: linux-nvdimm@lists.01.org Link: http://lkml.kernel.org/r/148417664156.131935.2248592164852799738.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-09x86/boot: Add missing declaration of string functionsNicholas Mc Guire1-0/+1
Add the missing declarations of basic string functions to string.h to allow a clean build. Fixes: 5be865661516 ("String-handling functions for the new x86 setup code.") Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Link: http://lkml.kernel.org/r/1483781911-21399-1-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-06-08x86, asm: use bool for bitops and other assembly outputsH. Peter Anvin1-1/+1
The gcc people have confirmed that using "bool" when combined with inline assembly always is treated as a byte-sized operand that can be assumed to be 0 or 1, which is exactly what the SET instruction emits. Change the output types and intermediate variables of as many operations as practical to "bool". Signed-off-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1465414726-197858-3-git-send-email-hpa@linux.intel.com Reviewed-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2015-03-23x86/boot: Standardize strcmp()Arjun Sreedharan1-1/+1
strcmp() is always expected to return 0 when arguments are equal, negative when its first argument @str1 is less than its second argument @str2 and a positive value otherwise. Previously strcmp("a", "b") returned 1. Now it gives -1, as it is supposed to. Until now this bug never triggered, because all uses for strcmp() in the boot code tested for nonzero: triton:~/tip> git grep strcmp arch/x86/boot/ arch/x86/boot/boot.h:int strcmp(const char *str1, const char *str2); arch/x86/boot/edd.c: if (!strcmp(eddarg, "skipmbr") || !strcmp(eddarg, "skip")) { arch/x86/boot/edd.c: else if (!strcmp(eddarg, "off")) arch/x86/boot/edd.c: else if (!strcmp(eddarg, "on")) should in the future strcmp() be used in a comparative way in the boot code, it might have led to (not so subtle) bugs. Signed-off-by: Arjun Sreedharan <arjun024@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1426520267-1803-1-git-send-email-arjun024@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-08x86, boot: Remove misc.h inclusion from compressed/string.cVivek Goyal1-6/+0
Given the fact that we removed inclusion of boot.h from boot/string.c does not look like we need misc.h inclusion in compressed/string.c. So remove it. misc.h was also pulling in string_32.h which in turn had macros for memcmp and memcpy. So we don't need to #undef memcmp and memcpy anymore. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Link: http://lkml.kernel.org/r/1398447972-27896-3-git-send-email-vgoyal@redhat.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-05-08x86, boot: Do not include boot.h in string.cVivek Goyal1-1/+2
string.c does not require whole of boot.h. Just inclusion of linux/types.h and ctypes.h seems to be sufficient. Keep list of stuff being included in string.c to bare minimal so that string.c can be included in other places easily. For example, Currently boot/compressed/string.c includes boot/string.c but looks like it does not want boot/boot.h. Hence there is a define in boot/compressed/misc.h "define BOOT_BOOT_H" which prevents inclusion of boot.h in compressed/string.c. And compressed/string.c is forced to include misc.h just for that reason. So by removing inclusion of boot.h, we can also get rid of inclusion of misch.h in compressed/misc.c. This also enables including of boot/string.c in purgatory/ code relatively easily. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Link: http://lkml.kernel.org/r/1398447972-27896-2-git-send-email-vgoyal@redhat.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-03-19x86, boot: Move memcmp() into string.h and string.cVivek Goyal1-0/+14
Try to treat memcmp() in same way as memcpy() and memset(). Provide a declaration in boot/string.h and by default user gets a memcmp() which maps to builtin function. Move optimized definition of memcmp() in boot/string.c. Now a user can do #undef memcmp and link against string.c to use optimzied memcmp(). It also simplifies boot/compressed/string.c where we had to redefine memcmp(). That extra definition is gone now. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Link: http://lkml.kernel.org/r/1395170800-11059-5-git-send-email-vgoyal@redhat.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-12-12x86, efi: EFI boot stub supportMatt Fleming1-0/+35
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>
2010-07-13x86, setup: Make the setup code also accept console=uart8250Yinghai Lu1-0/+22
Make the boot code also accept the console=uart8250,io,0x2f8,115200n form of early console. Also add back simple_guess_base(), otherwise those simple_strtoull(,,0) are not going to work. Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <4C3CCE05.4090505@kernel.org> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-07-12x86, setup: Early-boot serial I/O supportPekka Enberg1-0/+41
This patch adds serial I/O support to the real-mode setup (very early boot) printf(). It's useful for debugging boot code when running Linux under KVM, for example. The actual code was lifted from early printk. Cc: Cyrill Gorcunov <gorcunov@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> LKML-Reference: <1278835617-11368-1-git-send-email-penberg@cs.helsinki.fi> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2008-04-19x86: remove pointless commentsWANG Cong1-2/+0
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>
2007-10-11i386: move bootThomas Gleixner1-0/+52
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> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>