linux-hardened/arch/x86/entry
Nadav Amit 5bdcd510c2 x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs
As described in:

  77b0bf55bc: ("kbuild/Makefile: Prepare for using macros in inline assembly code to work around asm() related GCC inlining bugs")

GCC's inlining heuristics are broken with common asm() patterns used in
kernel code, resulting in the effective disabling of inlining.

The workaround is to set an assembly macro and call it from the inline
assembly block - which is also a minor cleanup for the jump-label code.

As a result the code size is slightly increased, but inlining decisions
are better:

      text     data     bss      dec     hex  filename
  18163528 10226300 2957312 31347140 1de51c4  ./vmlinux before
  18163608 10227348 2957312 31348268 1de562c  ./vmlinux after (+1128)

And functions such as intel_pstate_adjust_policy_max(),
kvm_cpu_accept_dm_intr(), kvm_register_readl() are inlined.

Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20181005202718.229565-4-namit@vmware.com
Link: https://lore.kernel.org/lkml/20181003213100.189959-11-namit@vmware.com/T/#u
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-06 15:52:17 +02:00
..
syscalls x86: Wire up restartable sequence system call 2018-06-06 11:58:32 +02:00
vdso x86/vdso: Fix vDSO build if a retpoline is emitted 2018-08-20 18:04:41 +02:00
vsyscall docs: Fix some broken references 2018-06-15 18:10:01 -03:00
calling.h x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs 2018-10-06 15:52:17 +02:00
common.c rseq: Avoid infinite recursion when delivering SIGSEGV 2018-06-22 19:04:22 +02:00
entry_32.S x86/entry/32: Check for VM86 mode in slow-path check 2018-07-20 22:33:41 +02:00
entry_64.S Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-08-13 13:35:26 -07:00
entry_64_compat.S x86/entry/64/compat: Fix "x86/entry/64/compat: Preserve r8-r11 in int $0x80" 2018-06-27 09:35:40 +02:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
syscall_32.c syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64 2018-04-05 16:59:38 +02:00
syscall_64.c syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64 2018-04-05 16:59:38 +02:00
thunk_32.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00
thunk_64.S x86: move exports to actual definitions 2016-08-07 23:47:15 -04:00