kernel/git/stable/linux.git/arch/x86/Makefile, branch linux-3.2.y

x86/retpoline: Remove compile time warning

2018-03-19T18:58:33+00:00

commit b8b9ce4b5aec8de9e23cabb0a26b78641f9ab1d6 upstream. Remove the compile time warning when CONFIG_RETPOLINE=y and the compiler does not have retpoline support. Linus rationale for this is: It's wrong because it will just make people turn off RETPOLINE, and the asm updates - and return stack clearing - that are independent of the compiler are likely the most important parts because they are likely the ones easiest to target. And it's annoying because most people won't be able to do anything about it. The number of people building their own compiler? Very small. So if their distro hasn't got a compiler yet (and pretty much nobody does), the warning is just annoying crap. It is already properly reported as part of the sysfs interface. The compile-time warning only encourages bad things. Fixes: 76b043848fd2 ("x86/retpoline: Add initial retpoline support") Requested-by: Linus Torvalds Signed-off-by: Thomas Gleixner Cc: David Woodhouse Cc: Peter Zijlstra (Intel) Cc: gnomes@lxorguk.ukuu.org.uk Cc: Rik van Riel Cc: Andi Kleen Cc: Josh Poimboeuf Cc: thomas.lendacky@amd.com Cc: Linus Torvalds Cc: Jiri Kosina Cc: Andy Lutomirski Cc: Dave Hansen Cc: Kees Cook Cc: Tim Chen Cc: Greg Kroah-Hartman Link: https://lkml.kernel.org/r/CA+55aFzWgquv4i6Mab6bASqYXg3ErV3XDFEYf=GEcCDQg5uAtw@mail.gmail.com Signed-off-by: Ben Hutchings

x86/retpoline: Add initial retpoline support

2018-03-19T18:58:31+00:00

commit 76b043848fd22dbf7f8bf3a1452f8c70d557b860 upstream. Enable the use of -mindirect-branch=thunk-extern in newer GCC, and provide the corresponding thunks. Provide assembler macros for invoking the thunks in the same way that GCC does, from native and inline assembler. This adds X86_FEATURE_RETPOLINE and sets it by default on all CPUs. In some circumstances, IBRS microcode features may be used instead, and the retpoline can be disabled. On AMD CPUs if lfence is serialising, the retpoline can be dramatically simplified to a simple "lfence; jmp *\reg". A future patch, after it has been verified that lfence really is serialising in all circumstances, can enable this by setting the X86_FEATURE_RETPOLINE_AMD feature bit in addition to X86_FEATURE_RETPOLINE. Do not align the retpoline in the altinstr section, because there is no guarantee that it stays aligned when it's copied over the oldinstr during alternative patching. [ Andi Kleen: Rename the macros, add CONFIG_RETPOLINE option, export thunks] [ tglx: Put actual function CALL/JMP in front of the macros, convert to symbolic labels ] [ dwmw2: Convert back to numeric labels, merge objtool fixes ] Signed-off-by: David Woodhouse Signed-off-by: Thomas Gleixner Acked-by: Arjan van de Ven Acked-by: Ingo Molnar Cc: gnomes@lxorguk.ukuu.org.uk Cc: Rik van Riel Cc: Andi Kleen Cc: Josh Poimboeuf Cc: thomas.lendacky@amd.com Cc: Peter Zijlstra Cc: Linus Torvalds Cc: Jiri Kosina Cc: Andy Lutomirski Cc: Dave Hansen Cc: Kees Cook Cc: Tim Chen Cc: Greg Kroah-Hartman Cc: Paul Turner Link: https://lkml.kernel.org/r/1515707194-20531-4-git-send-email-dwmw@amazon.co.uk [bwh: Backported to 3.2: - Add C source to export the thunk symbols - Drop ANNOTATE_NOSPEC_ALTERNATIVE since we don't have objtool - Use the first available feaure numbers - Adjust filename, context] Signed-off-by: Ben Hutchings

x86, relocs: Build clean fix

2012-05-30T23:44:09+00:00

commit b2d668da9307c4c163dd603d2bb3cadb10f9fd37 upstream. relocs was not cleaned up when "make clean" is issued. This patch fixes the issue. Signed-off-by: Jarkko Sakkinen Link: http://lkml.kernel.org/r/1337622684-6834-1-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: H. Peter Anvin Signed-off-by: Ben Hutchings

x86, realmode: 16-bit real-mode code support for relocs tool

2012-05-30T23:44:08+00:00

commit 6520fe5564acf07ade7b18a1272db1184835c487 upstream. A new option is added to the relocs tool called '--realmode'. This option causes the generation of 16-bit segment relocations and 32-bit linear relocations for the real-mode code. When the real-mode code is moved to the low-memory during kernel initialization, these relocation entries can be used to relocate the code properly. In the assembly code 16-bit segment relocations must be relative to the 'real_mode_seg' absolute symbol. Linear relocations must be relative to a symbol prefixed with 'pa_'. 16-bit segment relocation is used to load cs:ip in 16-bit code. Linear relocations are used in the 32-bit code for relocatable data references. They are declared in the linker script of the real-mode code. The relocs tool is moved to arch/x86/tools/relocs.c, and added new target archscripts that can be used to build scripts needed building an architecture. be compiled before building the arch/x86 tree. [ hpa: accelerating this because it detects invalid absolute relocations, a serious bug in binutils 2.22.52.0.x which currently produces bad kernels. ] Signed-off-by: H. Peter Anvin Link: http://lkml.kernel.org/r/1336501366-28617-2-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: Jarkko Sakkinen Signed-off-by: H. Peter Anvin Cc: [bwh: Backported to 3.2: - Adjust context (no archheaders; no insn_sanity) - Expand put_unaligned_le32()] Signed-off-by: Ben Hutchings

Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2010-10-21T20:06:00+00:00

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86-64, asm: If the assembler supports fxsave64, use it i386: Make kernel_execve() suitable for stack unwinding

x86-64, asm: If the assembler supports fxsave64, use it

2010-10-13T23:00:29+00:00

Kbuild allows for us to probe for the existence of specific constructs in the assembler, use them to find out if we can use fxsave64 and permit the compiler to generate better code. Signed-off-by: H. Peter Anvin

x86, build: Disable -fPIE when compiling with CONFIG_CC_STACKPROTECTOR=y

2010-09-13T22:53:16+00:00

The arch/x86/Makefile uses scripts/gcc-x86_$(BITS)-has-stack-protector.sh to check if cc1 supports -fstack-protector. When -fPIE is passed to cc1, these scripts fail causing stack protection to be disabled even when it is available. This fix is similar to commit c47efe5548abbf53c2f66e06dcb46183b11d6b22 Reported-by: Kai Dietrich Signed-off-by: Magnus Granberg LKML-Reference: <20100913101319.748A1148E216@opensource.dyc.edu> Signed-off-by: Anthony G. Basile Cc: Andrew Morton Signed-off-by: H. Peter Anvin

x86: Use .cfi_sections for assembly code

2010-05-14T05:15:18+00:00

The newer assemblers support the .cfi_sections directive so we can put the CFI from .S files into the .debug_frame section that is preserved in unstripped vmlinux and in separate debuginfo, rather than the .eh_frame section that is now discarded by vmlinux.lds.S. Signed-off-by: Roland McGrath LKML-Reference: <20100514044303.A6FE7400BE@magilla.sf.frob.com> Signed-off-by: H. Peter Anvin

x86-64: Allow fbdev primary video code

2010-02-17T05:22:26+00:00

For some reason the 64-bit tree was doing this differently and I can't see why it would need to. This correct behaviour when you have two GPUs plugged in and 32-bit put the console in one place and 64-bit in another. Signed-off-by: Dave Airlie LKML-Reference: <1262847894-27498-1-git-send-email-airlied@gmail.com> Signed-off-by: H. Peter Anvin

Merge branch 'perf/core' into perf/probes

2009-11-17T09:17:47+00:00

Resolved merge conflict in tools/perf/Makefile Merge reason: we want to queue up a dependent patch. Signed-off-by: Ingo Molnar