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| author | David Woodhouse <dwmw2@infradead.org> | 2014-01-30 12:00:28 +0100 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2014-01-30 17:04:32 +0100 |
| commit | 5fbbc25a99d680feca99a3095f0440f65d4307cc (patch) | |
| tree | bfdb7c982c8d742d3a1c153558df8416073758fa /arch/x86/Makefile | |
| parent | Merge commit 'f4bcd8ccddb02833340652e9f46f5127828eb79d' into x86/build (diff) | |
| download | linux-5fbbc25a99d680feca99a3095f0440f65d4307cc.tar.xz linux-5fbbc25a99d680feca99a3095f0440f65d4307cc.zip | |
x86, boot: Fix word-size assumptions in has_eflag() inline asm
Commit dd78b97367bd575918204cc89107c1479d3fc1a7 ("x86, boot: Move CPU
flags out of cpucheck") introduced ambiguous inline asm in the
has_eflag() function. In 16-bit mode want the instruction to be
'pushfl', but we just say 'pushf' and hope the compiler does what we
wanted.
When building with 'clang -m16', it won't, because clang doesn't use
the horrid '.code16gcc' hack that even 'gcc -m16' uses internally.
Say what we mean and don't make the compiler make assumptions.
[ hpa: ideally we would be able to use the gcc %zN construct here, but
that is broken for 64-bit integers in gcc < 4.5.
The code with plain "pushf/popf" is fine for 32- or 64-bit mode, but
not for 16-bit mode; in 16-bit mode those are 16-bit instructions in
.code16 mode, and 32-bit instructions in .code16gcc mode. ]
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Link: http://lkml.kernel.org/r/1391079628.26079.82.camel@shinybook.infradead.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/Makefile')
0 files changed, 0 insertions, 0 deletions