Messages in this thread | | | Date | Wed, 29 Jan 2014 08:57:40 -0800 | Subject | Re: [PATCH] x86, boot: fix word-size assumptions in has_eflag() inline asm | From | Kees Cook <> |
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On Wed, Jan 29, 2014 at 4:01 AM, David Woodhouse <dwmw2@infradead.org> wrote: > Commit dd78b97367bd575918204cc89107c1479d3fc1a7 ("x86, boot: Move CPU > flags out of cpucheck") introduced ambiguous inline asm in the > has_eflag() function. We 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. > > Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Yes, excellent point. Thanks!
Acked-by: Kees Cook <keescook@chromium.org>
-Kees
-- Kees Cook Chrome OS Security
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