kernel.git/arch/x86/Makefile, branch linux-4.18.y

x86: Allow generating user-space headers without a compiler

2018-09-05T07:29:51Z

commit 829fe4aa9ac16417a904ad1de1307de906854bcf upstream. When bootstrapping an architecture, it's usual to generate the kernel's user-space headers (make headers_install) before building a compiler. Move the compiler check (for asm goto support) to the archprepare target so that it is only done when building code for the target. Fixes: e501ce957a78 ("x86: Force asm-goto") Reported-by: Helmut Grohne Signed-off-by: Ben Hutchings Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180829194317.GA4765@decadent.org.uk Signed-off-by: Greg Kroah-Hartman

Merge branch 'linus' into x86/urgent

2018-06-22T19:20:35Z

Required to queue a dependent fix.

x86/build: Remove unnecessary preparation for purgatory

2018-06-21T10:55:05Z

kexec-purgatory.c is properly generated when Kbuild descend into the arch/x86/purgatory/. Thus the 'archprepare' target is redundant. Signed-off-by: Masahiro Yamada Cc: Linus Torvalds Cc: Michal Marek Cc: Peter Zijlstra Cc: Sam Ravnborg Cc: Thomas Gleixner Link: https://lore.kernel.org/lkml/1529401422-28838-3-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Ingo Molnar

Revert "kexec/purgatory: Add clean-up for purgatory directory"

2018-06-21T10:55:05Z

Reverts the following commit: b0108f9e93d0 ("kexec: purgatory: add clean-up for purgatory directory") ... which incorrectly stated that the kexec-purgatory.c and purgatory.ro files were not removed after 'make mrproper'. In fact, they are. You can confirm it after reverting it. $ make mrproper $ touch arch/x86/purgatory/kexec-purgatory.c $ touch arch/x86/purgatory/purgatory.ro $ make mrproper CLEAN arch/x86/purgatory $ ls arch/x86/purgatory/ entry64.S Makefile purgatory.c setup-x86_64.S stack.S string.c This is obvious from the build system point of view. arch/x86/Makefile adds 'arch/x86' to core-y. Hence 'make clean' descends like this: arch/x86/Kbuild -> arch/x86/purgatory/Makefile Signed-off-by: Masahiro Yamada Cc: Linus Torvalds Cc: Michal Marek Cc: Peter Zijlstra Cc: Sam Ravnborg Cc: Thomas Gleixner Link: https://lore.kernel.org/lkml/1529401422-28838-2-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Ingo Molnar

kbuild: add machine size to CHECKFLAGS

2018-06-01T02:36:58Z

By default, sparse assumes a 64bit machine when compiled on x86-64 and 32bit when compiled on anything else. This can of course create all sort of problems for the other archs, like issuing false warnings ('shift too big (32) for type unsigned long'), or worse, failing to emit legitimate warnings. Fix this by adding the -m32/-m64 flag, depending on CONFIG_64BIT, to CHECKFLAGS in the main Makefile (and so for all archs). Also, remove the now unneeded -m32/-m64 in arch specific Makefiles. Signed-off-by: Luc Van Oostenryck Signed-off-by: Masahiro Yamada

Merge branch 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-04-02T21:37:03Z

Pull x86 build updates from Ingo Molnar: "The biggest change is the forcing of asm-goto support on x86, which effectively increases the GCC minimum supported version to gcc-4.5 (on x86)" * 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/build: Don't pass in -D__KERNEL__ multiple times x86: Remove FAST_FEATURE_TESTS x86: Force asm-goto x86/build: Drop superfluous ALIGN from the linker script

x86/build: Don't pass in -DKERNEL multiple times

2018-03-31T06:02:07Z

Some ..cmd files under arch/x86 are showing two instances of -D__KERNEL__, like arch/x86/boot/ and arch/x86/realmode/rm/. __KERNEL__ is already defined in KBUILD_CPPFLAGS in the top Makefile, so it can be dropped safely. Signed-off-by: Cao jin Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Masahiro Yamada Cc: Michal Marek Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kbuild@vger.kernel.org Link: http://lkml.kernel.org/r/20180316084944.3997-1-caoj.fnst@cn.fujitsu.com Signed-off-by: Ingo Molnar

x86: Force asm-goto

2018-03-20T09:58:02Z

We want to start using asm-goto to guarantee the absence of dynamic branches (and thus speculation). A primary prerequisite for this is of course that the compiler supports asm-goto. This effecively lifts the minimum GCC version to build an x86 kernel to gcc-4.5. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Cc: torvalds@linux-foundation.org Link: https://lkml.kernel.org/r/20180319201327.GJ4043@hirez.programming.kicks-ass.net

x86/build/64: Force the linker to use 2MB page size

2018-03-20T07:03:03Z

Binutils 2.31 will enable -z separate-code by default for x86 to avoid mixing code pages with data to improve cache performance as well as security. To reduce x86-64 executable and shared object sizes, the maximum page size is reduced from 2MB to 4KB. But x86-64 kernel must be aligned to 2MB. Pass -z max-page-size=0x200000 to linker to force 2MB page size regardless of the default page size used by linker. Tested with Linux kernel 4.15.6 on x86-64. Signed-off-by: H.J. Lu Cc: Andy Shevchenko Cc: Eric Biederman Cc: H. Peter Anvin Cc: Juergen Gross Cc: Kees Cook Cc: Kirill A. Shutemov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/CAMe9rOp4_%3D_8twdpTyAP2DhONOCeaTOsniJLoppzhoNptL8xzA@mail.gmail.com Signed-off-by: Ingo Molnar

objtool, retpolines: Integrate objtool with retpoline support more closely

2018-02-21T15:54:32Z

Disable retpoline validation in objtool if your compiler sucks, and otherwise select the validation stuff for CONFIG_RETPOLINE=y (most builds would already have it set due to ORC). Signed-off-by: Peter Zijlstra (Intel) Acked-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Arjan van de Ven Cc: Borislav Petkov Cc: Dan Williams Cc: Dave Hansen Cc: David Woodhouse Cc: Greg Kroah-Hartman Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Signed-off-by: Ingo Molnar